RECOMMENDATIONS FOR THE MANAGEMENT OF ADULTS WITH CONGENITAL HEART DISEASE - 2001 (PART 2)
1 | 2 | 3 Click here to view other parts.
- Section V - Left Ventricular Outflow Tract Obstruction & Bicuspid Aortic Valve
- Section VI - Coarctation of the Aorta
- Section VII - Right Ventricular Outflow Tract Obstruction
- Section VIII - Tetralogy of Fallot
- Section IX - Ebstein Anomaly
- Section X - Marfan syndrome
- Bibliography
Section V - Left Ventricular Outflow Tract Obstruction
& Bicuspid Aortic Valve
Part l - Background Information
Definition: This section concerns left ventricular outflow tract obstruction (LVOTO) in the setting of concordant atrioventricular and ventriculoarterial connections. (Neither hypertrophic cardiomyopathy nor interrupted aortic arch will be considered here.)
LVOTO can occur at several levels:
- Supravalvar LVOTO may occur rarely in isolation as an hourglass deformity. It is more often diffuse however, involving the major arteries to varying degrees and begins at the superior margin of the sinuses of Valsalva.
- Valvar LVOTO in the adult patient with CHD is usually due to bicuspid aortic valve (rheumatic and trileaflet calcific aortic stenosis are excluded here). It usually occurs in isolation but is associated with other abnormalities, the most common being coarctation of the aorta (which should be sought), PDA, or ascending aortopathy.
- Subvalvar LVOTO is usually either a discrete fibromuscular ridge which partially or completely encircles the left ventricular outflow tract or is a long fibromuscular narrowing beneath the base of the aortic valve. Occasionally, there is a tunnel-like narrowing of the whole left ventricular outflow tract with a small aortic root. Rarely, abnormal insertion of the mitral valve or accessory mitral leaflet may cause significant obstruction.
Supravalvar LVOTO is usually part of Williams syndrome, which is a contiguous gene syndrome associated with neurodevelopmental and multisystem manifestations caused by a deletion at chromosome 7q11.23, but may be familial with normal facies, or associated with rubella syndrome.
Bicuspid aortic valve is the most common congenital cardiac anomaly occurring in 1-2% of the population with a male predominance (4:1).
Subvalvar LVOTO has also a male predominance (2:1). A genetic predisposition has been suggested as there are reports of a familial incidence.
Supravalvar LVOTO is usually progressive and aortic regurgitation is common. With Williams syndrome, there are often associated peripheral pulmonary artery or systemic arterial (including coronary ostial) stenoses, which may worsen, resolve or remain unchanged. Systemic hypertension is common.
Valvar LVOTO commonly progresses as the patient grows but the rate is variable. Some patients with bicuspid aortic valve will not experience any problems, although there is the lifelong risk of endocarditis. Others will develop aortic stenosis (especially after calcification of the valve in the sixth decade), aortic regurgitation, aortic dissection or aneurysmal aortic root dilation (irrespective of altered hemodynamics or age) (51,52). If there is associated coarctation, this should usually be dealt with first (unless there is critical LVOTO; if both are severe, they may be dealt with at one operation via an anterior approach with an ascending to descending aortic graft and concomitant aortic valve replacement).
Subvalvar LVOTO often progresses, but the rate is variable, and low gradients may remain for many years. It is often associated with aortic regurgitation (up to 60% of cases) through an otherwise normal valve which has been damaged by the subvalvar jet of blood. It may also progress, but seldom becomes more than moderate. There may be associated small VSDs. These patients are particularly prone to endocarditis. Tunnel-like subvalvar LVOTO is progressive and requires surgery for relief of obstruction although this may be technically difficult because the aortic root is small. Subvalvar LVOTO may occur with a variety of associated lesions.
An adequate initial workup:
- Documents the level(s) of obstruction.
- Quantitates the severity and anatomy of the obstruction(s).
- Identifies associated abnormalities including aortic regurgitation, proximal aortic dilation, aortic coarctation and the associated anomalies of Williams and Shone syndromes.
- A thorough clinical assessment.
- ECG.
- Chest x-ray.
- Transthoracic echo-Doppler examination by an appropriately trained individual to determine the level(s) of obstruction, septal thickness, size of both the aortic root and ascending aorta.
- TEE to define the anatomy precisely if unclear from TTE.
- Exercise testing.
- A heart catheterization ± provocative testing to assess the hemodynamics and severity of obstruction.
- Coronary angiography and aortography if surgery is being planned.
- MRI to assess associated lesions such as pulmonary artery stenoses or aortic coarctation and to measure left ventricular mass and function.
- Abdominal aortography to identify significant renal or other arterial stenoses.
| Supravalvar LVOTO may require intervention for a cath gradient or mean echo gradient of > 50 mmHg if the obstruction is discrete. Criteria for intervention for diffuse obstruction are not well defined but are probably similar since the end effect on the coronary arteries and the myocardium are the same. | ||
| Valvar LVOTO requires intervention for symptoms (dyspnea, angina, presyncope or syncope) or, arguably, "critical" aortic stenosis (valve area < 0.6cm2). Intervention may be indicated occasionally for other reasons (e.g. a person with a lesser degree of obstruction who wishes to play vigorous sports or wishes to become pregnant). Bicuspid aortic valves may also require intervention for moderate or severe regurgitation associated with exertional symptoms, or left ventricular end systolic dimensions > 55mm or LVEF < 55%.; aortic root replacement is required for ascending aortic dissection and should be considered prophylactically for proximal aortic dilation (> 55 mm). | ||
| Subvalvar LVOTO should be considered for intervention when a resting cath gradient or mean echo gradient is > 50 mmHg, symptoms develop, or if combined with progressive aortic regurgitation which is more than mild. If there is an associated VSD, the gradient may be underestimated and important subvalvar LVOTO may become manifest only after VSD closure. | ||
Re-operation is indicated after valvotomy or after surgery for:
|
||
| Patients who require operation for supravalvar LVOTO should be operated on by congenital heart surgeons with experience with the technique. | ||
Supravalvar LVOTO requires patch aortoplasty or, rarely, replacement of the proximal ascending aorta.
Valvar LVOTO may be treated with balloon valvuloplasty (if the valve is non-calcified); open aortic valvotomy; or valve replacement using a mechanical valve, biological valve or pulmonary autograft (Ross procedure which consists of replacing the aortic valve with the patient's pulmonary valve and implanting a homograft in the pulmonary position). Aortic valve disease, isolated or in combination with supravalvar or subvalvar stenosis, has been increasingly treated by pulmonary autografts, especially in young adults. The choice depends on the availability and skills of the team available and the preference of the patient.
| Pulmonary autograft (Ross procedure) and balloon valvuloplasty for valvar LVOTO should be performed in centres and by people with substantial experience in these procedures. | ||
Discrete subvalvar LVOTO requires surgical resection almost invariably associated with myomectomy or myotomy. In older patients, the aortic valve may also need to be replaced or repaired because of significant aortic regurgitation.
Tunnel-like subvalvar LVOTO may require augmentation of the LVOTO using the Konno procedure (aortoventriculoplasty with aortic valve replacement) or other modifications for enlargement of the outflow tract. In the past, a left ventricular apex-to-aorta valved conduit was implanted if it was impossible to relieve the LVOTO adequately by any other means, but the long-term durability was unacceptable and the procedure has been abandoned. Some of these patients are still alive.
Subvalvar LVOTO associated with repair of AVSD often recurs if the fibromuscular tissue alone is excised. Patch enlargement of the infundibular septum and patch enlargement of the superior bridging leaflet of the left AV (mitral) valve or left AV (mitral) valve replacement may be required.
| Patients who require operation for subvalvar LVOTO should be operated on by congenital heart surgeons with experience with the technique. | ||
Supravalvar LVOTO should have a low operative mortality.. Recurrence of obstruction is uncommon. The long-term durability of the patches or conduits used to relieve the obstruction may be a problem and surveillance should include assessment for aneurysm and endocarditis.
Valvar LVOTO treated by valvotomy or valvuloplasty is associated with progressive recurrent stenosis and calcification, and/or progressive regurgitation, and may eventually require valve replacement.
Patients with subaortic stenosis who require valve replacement will have a course similar to those who have valve replacement for acquired valvar LVOTO.
| Patients with pulmonary autografts have excellent hemodynamic characteristics, require no anticoagulation, and have much reduced risk of thromboembolism. However the pulmonary autograft may deteriorate with time, as may the pulmonary homograft leading to stenosis and/or regurgitation. These patients need long-term follow up | ||
Recurrence of fibromuscular subvalvar LVOTO is not uncommon (up to 20% over a decade, particularly if the aortic root is small).
Tunnel-like subvalvar LVOTO with extensive repair with or without aortic valve replacement has a high recurrence risk (72) although newer techniques may improve this.
Clinically important aortic regurgitation following subvalvar LVOTO repair is not uncommon (up to 25% of patients).
LVOTO lesions associated with increased maternal and fetal risk during pregnancy include severe LVOTO with or without symptoms, aortic regurgitation with functional class III to IV, LVOTO with severe LV dysfunction, and mechanical prosthetic valves requiring anticoagulation. The latter underscores the importance, when feasible, of valve reconstruction or consideration of a bioprosthesis or pulmonary autograft procedure rather than replacement with a mechanical prosthesis in women having preconception cardiac surgery (73).
Patients with mild to moderate LVOTO and normal LV function can usually be managed conservatively through the entire pregnancy. Patients with more severe obstruction (cath gradient or mean echo gradient > 50 mmHg prior to pregnancy) or symptoms should be advised to delay conception until relief of LVOTO is performed. Balloon dilation of a severely stenotic bicuspid valve during pregnancy can reduce the hazards of gestation, labor and delivery (74,75).
Aortic regurgitation with LVOTO can usually be managed medically with a combination of diuretics and/or vasodilators. Surgery during pregnancy should be contemplated only for the control of refractory functional class III or IV symptoms.
The presence of bicuspid aortic valve and ascending aortic medial abnormality may predispose to spontaneous aortic dissection in the third trimester.
|
All patients should have regular cardiology follow up. Patients with Williams or Shone syndrome and those with complex LVOTO with or without repair should be followed by an ACHD cardiologist.
Particular attention should be paid to:
|
||
Section VI - Coarctation of the Aorta
Part I - Background Information
Coarctation of the aorta is a stenosis, usually but not always, in the region of the ligamentum arteriosum. Rarely, it can occur in the ascending or abdominal aorta. It is usually discrete but may be associated with diffuse hypoplasia of the aortic arch and isthmus. The specific anatomy, severity and degree of hypoplasia proximal to the aortic coarctation is highly variable.
Simple aortic coarctation refers to discrete coarctation in the absence of other intracardiac lesions. It is the most common form detected de novo in adults. "'Complex' aortic coarctation is used to describe coarctation in the presence of other important intracardiac anomalies and is usually detected in infancy. The most common associated abnormalities are VSD, aortic stenosis, subaortic stenosis or a combination, accounting for 2/3 of cases of 'complex' aortic coarctation. The ratio of 'simple' to 'complex' aortic coarctation is approximately 1:1.
A significant aortic coarctation is usually one with right arm hypertension and a peak pull back gradient of more than 20 mmHg across the coarctation site at angiography. If there is extensive collateral circulation, a significant aortic coarctation may have minimal or no pressure gradient and even acquired aortic atresia.
Associated cardiovascular abnormalities include:
- Bicuspid aortic valve (up to 85%).
- Berry (intracranial) aneurysms of the circle of Willis (3-5%).
- Anomalies of the brachiocephalic circulation such as anomalous origin of the right subclavian artery (5%) or involvement of the left subclavian artery in the coarctation.
- Collateral circulation both anteriorly (involving the internal mammary arteries) and posteriorly (involving the intercostal arteries).
- Aortic medial disease in the para-coarctation aorta, and in the ascending aorta if a bicuspid aortic valve is present.
- VSD.
Non-cardiovascular abnormalities, involving the respiratory, gastrointestinal, genitourinary tracts or musculoskeletal system have been reported in up to 25% of cases. There is good evidence that coarctation is usually associated with a diffuse arteriopathy that persists even after repair of the coarctation itself.
Coarctation of the aorta is more common in males, with a male to female ratio of 1.3-1.7:1. It is usually sporadic, but genetic influences can play a role (up to 35% of Turner syndrome (45,X) females have aortic coarctation). Very rarely, it may be autosomal dominant.
Presentation in adolescence/adulthood is usually with upper limb hypertension, differential arm-leg pulses, headaches, exertional leg fatigue or an incidental murmur. Symptoms are often absent. Rarely, presentation may be with an intracerebral hemorrhage. An occasional patient may be diagnosed from the typical x-ray appearance.
The mean survival (prior to widespread surgical repair and modern diagnostic methods) of patients with untreated aortic coarctation was 35 years, with 75% mortality by 46 years of age. Most developed systemic hypertension, typically during childhood, and ultimately, by the 5th decade, left ventricular failure.
Death in untreated aortic coarctation is usually due to:
- Heart failure, usually beyond 30 years of age (28%).
- Aortic rupture/dissection (21%).
- Infective endarteritis/endocarditis (18%).
- Cerebral hemorrhage (12%).
- Premature coronary artery disease.
- Concomitant aortic valve disease (usually involving a bicuspid aortic valve).
An initial diagnostic workup should document:
- The location and type of aortic coarctation together with its severity.
- The presence (or absence) and severity of other intracardiac lesions (bicuspid aortic valve, mitral valve abnormalities, subaortic stenosis, VSD).
- Left ventricular function and the presence (or absence) of left ventricular hypertrophy.
- The presence (or absence) of other extracardiac cardiovascular anomalies such as collateral circulation, involvement of other vessels (subclavian/carotid stenoses) and associated aneurysms.
The diagnostic workup should include at a minimum:
- a thorough clinical assessment, including upper and lower limb blood pressure measurement, determination of radiofemoral pulse delay, palpation of femoral and distal pulses and auscultation for collaterals around the scapula.
- ECG which may show signs of left ventricular hypertrophy 'strain'.
- Chest x-ray which may show the '3 sign' (caused by indentation of the aorta at the site of the aortic coarctation, combined with dilation before and after the coarctation) or 'rib notching' (caused by erosion of the inferior border of the posterior ribs by enlarged intercostal arteries).
- Echo Doppler evaluation by an appropriately trained individual. The echo window, in particular the suprasternal arch view, may be difficult in adults.
- MRI to delineate the coarctation anatomy, possible aneurysm formation and with velocity mapping, assess the degree of restenosis. Contrast MR angiography may allow visualization of arch geometry and collaterals (76).
The diagnostic workup may require:
- Invasive angiography with hemodynamic measurements to assess the aortic coarctation gradient and nature of the obstruction and to determine the presence/absence of collaterals or aneurysm formation if appropriate information cannot be obtained by MRI, if MRI is not available, or if percutaneous intervention is not planned. If percutaneous intervention is planned, angiography can be performed at the time of procedure.
- Digital subtraction angiography (DSA) which provides good anatomical detail and may obviate the need for invasive arteriography.
- Complete heart catheterization with aortography if associated cardiovascular lesions are present.
- Coronary angiography because of the increased risk of premature coronary artery in these patients, if a clinical indication exists, if the patient is over 40 years (or younger if major coronary risk factors), or if there is any evidence of left ventricular failure.
| All patients with significant aortic coarctation or recoarctation, including those with proximal systemic hypertension (regardless of age) whether symptomatic or asymptomatic, warrant intervention. | ||
Patients with significant aortic valve stenosis may also require valve surgery, which may or may not be done at the same time as aortic coarctation repair. If operated upon separately, the sequence depends upon the severity of each of the lesions, the more severe one being dealt with first.
For aortic coarctation or recoarctation, intervention may be either surgical or percutaneous (78). Surgical repair remains the gold standard against which newer therapies must be compared.
| Surgical repair of aortic coarctation in adults is more hazardous than in children. It should be performed by congenital heart surgeons. | ||
Surgical repair may involve:
- Interposition graft.
- End-to-end anastomosis (usually the preferred method for initial repair).
- Patch aortoplasty.
- Arch augmentation.
- Jump graft by-passing the aortic coarctation segment.
- Subclavian flap aortoplasty (may be used in children, but not recommended in adults because of concern about the arterial supply to the arm).
| Balloon dilation and/or stent insertion is being used increasingly as an alternative to surgery and, in some centres, has replaced surgery as the primary management strategy, unless additional problems coexist. It is not an appropriate therapy if there is an interposition graft or important concomitant arch hypoplasia involving the origin of the left common carotid or in the proximal arch. It should only be performed in centres and by individuals with a commitment to the technique and to its clinical evaluation. | ||
If there is aortic stenosis, and the aortic coarctation is relieved first, re-evaluation of the aortic gradient is needed after the procedure. This is usually accomplished with echo Doppler.
Following surgical repair of simple aortic coarctation, the obstruction is usually relieved with minimal mortality (< 1%). Mortality is higher for re-operation (5 - 15%). Recurrent coarctation is more common when initially repaired in infancy.
Complications of surgical repair include:
- Paraplegia due to spinal cord ischemia. It is uncommon but recognized, particularly in patients who do not have well developed collateral circulation.
- Rebound paradoxical hypertension in the early post-operative phase. It may be due to rebound sympathetic activation and activation of the renin-angiotensin system. It usually responds to beta blockade.
- Recurrent laryngeal nerve palsy.
- Phrenic nerve injury with diaphragmatic paralysis.
- Aneurysm formation following patch aortoplasty (particularly Dacron). It occurs opposite the patch.
- Late dissection at the repair site is a rare complication but false aneurysms may occur.
- Arm claudication (rare) if subclavian flap aortoplasty has been used.
Balloon dilation and/or intravascular stenting for native aortic coarctation or recoarctation can be as effective as surgical repair in relieving stenoses, with similar mortality (81-83). Long-term outcomes are unknown.
Complications of balloon dilation and/or intravascular stenting include:
- Recoarctation. The rate is higher for balloon dilation without stenting compared to surgery, particularly for younger patients.
- Aneurysm formation (6-12% with native aortic coarctation) although this is substantially less with stent utilization.
- Femoral artery injury/thrombosis.
- Stroke (rare).
- Aortic rupture (rare).
Hemoptysis from a leaking/ruptured aneurysm is a life-threatening complication and requires immediate investigation and treatment. MRI or DSA are optimal because of the risk of rupture with aortography and also, at times, failure to visualize the aneurysm.
Long-term follow up after surgical repair has shown an increased incidence of premature cardiovascular disease and death (84).
Prior hypertension resolves in many patients but this may depend on the length of follow up and age at repair. If it fails to resolve, it is generally responsive to standard therapy. Systolic hypertension is common with exercise, the significance of which is unknown. It may be related to residual arch hypoplasia. Persistent exercise-induced upper limb hypertension may occur, even in the absence of any significant residual gradient.
Heart failure usually resolves.
Late strokes may occur, notably in those repaired as adults and in those with residual hypertension. Cerebral hemorrhage due to a ruptured berry aneurysm can occur late after repair, even in the absence of systemic hypertension.
Endocarditis/endarteritis can occur at the aortic coarctation site or involving associated lesions. If at the coarctation site, embolic manifestations are usually restricted to the abdominal viscera and legs.
| Females with aortic coarctation contemplating pregnancy should have repair prior to pregnancy. Management of hypertension in the unoperated pregnant patient may be problematic because too low a pressure below the coarctation site may result in abortion or death of the fetus. The risk of aortic dissection or aneurysm rupture during pregnancy is low, but death is likely if one of these occurs. | ||
All patients require periodic follow up by an ACHD cardiologist.
All patients should have a periodic MRI or angiogram following repair of the aortic coarctation to document the post-repair anatomy and mechanical complications (restenosis or aneurysm formation).
Particular attention should be directed towards:
- Residual hypertension, heart failure, coronary artery disease or other cardiac disease.
- Associated bicuspid aortic valve, which may develop stenosis or regurgitation later in life.
- Recurrent aortic coarctation or significant arm-leg blood pressure gradient at rest.
- Ascending aortopathy especially in the presence of bicuspid aortic valve.
- New or unusual headaches because of the possibility of berry aneurysms.
- Late dissection proximal or distal to the repair site.
- Aneurysm formation at the site of aortic coarctation repair, especially if either a Dacron patch or if balloon angioplasty has been used.
| Endocarditis prophylaxis is recommended for 6 months following coarctation repair or for life if any residual gradient or associated indications persist. | ||
Section VII - Right Ventricular Outflow Tract Obstruction
Part I - Background Information
Supravalvar RVOTO seldom occurs in isolation. It may occur in tetralogy of Fallot, Williams syndrome, Noonan syndrome, VSD, arteriohepatic dysplasia or congenital Rubella syndrome.
Valvar RVOTO, the most common form of RVOTO, is almost always congenital in origin. Typically, the stenotic pulmonic valve is a thin, pliable, dome-shaped structure, with a narrow opening at its apex. In 10-15% of cases, the valve is dysplastic with thickened and immobile cusps. In adults, the valve may calcify late in life.
Subvalvar (infundibular) RVOTO usually occurs in combination with other lesions, particularly ventricular septal defect, and as part of tetralogy of Fallot.
A separate but somewhat similar entity is "double-chambered right ventricle" with mid-cavity obstruction, often from a prominent moderator band. This may be associated with a VSD.
RVOTO (either valvar or subvalvar) may rarely occur in association with subaortic stenosis.
Branch pulmonary artery stenosis is not considered here.
Hemodynamic Severity Grading
The following is based on peak systolic pressure gradients at heart catheterization). It is time-honoured and useful for decisions regarding therapy.
Trivial: < 25 mmHg
Mild: 25-49 mmHg
Moderate: 50-79 mmHg
Severe or Critical: > 80 mmHg
Patients with Noonan syndrome (autosomal dominant inheritance) may present with pulmonary stenosis, ASD and restrictive cardiomyopathy. Mental retardation, abnormal facies, short stature, thoracic/penile and/or testicular abnormalities may also be present. Williams syndrome is a contiguous gene syndrome associated with cardiac (pulmonary stenosis, pulmonary artery stenosis, supravalvar aortic stenosis), neurodevelopmental (mental retardation, "cocktail personality") and multisystem manifestations (abnormal facies, short stature, hypercalcemia) caused by a deletion at chromosome 7q11.23. Patients with Alagille syndrome (autosomal dominant inheritance - also called arteriohepatic dysplasia) may have pulmonary stenosis, pulmonary arterial stenosis and abnormal facies (prominent overhanging forehead, deep-set eyes, small pointed chin).
Supravalvar RVOTO may progress in severity and should be monitored.
| Patients with trivial valvar RVOTO who are asymptomatic do not become worse with time as adults and will not require treatment, unless endocarditis occurs. | ||
Female patients often present to physicians during pregnancy because of an increase in the loudness of the murmur. Others may present because of enlarged pulmonary arteries detected on chest x-ray.
| Mild valvar RVOTO may progress in 20% of unoperated patients. Moderate stenosis may progress in up to 70% of unoperated patients. Some of these patients will also become symptomatic later in life because of atrial arrhythmias. When the gradient is moderate to severe or the patient is symptomatic, balloon valvotomy (or rarely surgical valvotomy) is recommended. | ||
Subvalvar RVOTO usually progresses in severity and often leads to the development of worsening right ventricular hypertrophy, symptoms, and critical gradients requiring surgical repair.
An adequate diagnostic workup:
- Documents the level(s) of obstruction.
- Quantitates the severity of the obstruction(s).
- Identifies associated abnormalities such as ASD, PDA, VSD and tetralogy of Fallot.
The diagnostic workup should include at a minimum:
- A thorough clinical assessment, paying particular attention to the 'a' wave on the venous pulse, the length of the murmur, the pulmonary component of the second sound and right ventricular hypertrophy.
- ECG.
- Chest x-ray, paying particular attention to valvar calcification on the lateral film.
- Echo Doppler examination by an appropriately trained individual.
The diagnostic workup may require:
- Oximetry (rest and exercise) to determine if there is cyanosis because of associated abnormalities (ASD or VSD).
- Heart catheterization (including angiocardiography) to assess hemodynamics and severity of obstruction and pulmonary artery abnormalities.
- Coronary angiography in patients at risk of coronary artery disease, or in patients over the age of 40 years in whom intervention is being planned.
- MRI to assess associated lesions such as pulmonary artery stenoses, co-existing pulmonary regurgitation and RV function if unable to properly assess these by echo or angiogram.
Intervention is indicated if:
|
||
Intervention is also indicated if:
|
||
|
Intervention may be indicated following an episode of endocarditis.
Re-intervention is indicated for:
|
||
| Balloon valvuloplasty is the treatment of choice for valvar RVOTO. Occasionally valve replacement may be necessary. | ||
| Balloon valvuloplasty for valvar RVOTO is an established technique but should still be performed only in centres and by teams with experience in this technique. | ||
|
Relief of obstruction in a double-chambered right ventricle is accomplished by surgical resection of right ventricular muscle bands.
Patients who require operation for supravalvar or subvalvar RVOTO should be operated on by congenital heart surgeons. |
||
The long-term results of surgical pulmonary valvotomy are established. Clinical outcomes are excellent. Relief of valvar RVOTO is usually maintained, but residual obstruction may progress. Occasionally pulmonary regurgitation may progress and become severe enough to warrant re-intervention. Long-term survival in surgical patients when valvar RVOTO occurs as an isolated lesion is close to normal. Long-term mortality may be increased, however, with greater age (> 21 years) at time of surgery.
Patients treated with balloon valvuloplasty, in the absence of a dysplastic valve, have the same prognosis as those who have had surgical valvotomy, at least in the medium term (95,96).
Subvalvar and supravalvar RVOTO seldom recur after adequate repair.
The increased hemodynamic load of pregnancy may precipitate right heart failure, atrial arrhythmias, or tricuspid regurgitation in patients with significant RVOTO, irrespective of the presence or absence of symptoms prior to pregnancy. Patients with moderate-to-severe RVOTO should, therefore, be considered for RVOTO relief prior to conception.
Balloon valvuloplasty for valvar pulmonary stenosis may be employed during pregnancy if the stenosis is severe or symptoms due to pulmonary stenosis develop. When possible, intervention should be delayed until after organogenesis.
Mild RVOTO or RVOTO which has been alleviated by valvuloplasty or surgery (with or without pulmonary regurgitation) is well tolerated.
|
Patients with trivial RVOTO (gradient < 25mmHg) do not require ACHD cardiology follow-up. Follow-up by a general physician and/or internist/cardiologist is sufficient unless new findings or symptoms occur.
Patients with mild or greater RVOTO or moderate to severe pulmonary regurgitation require monitoring by an ACHD cardiologist as intervention may be required. Particular attention should be paid to:
|
||
Section VIII - Tetralogy of Fallot
Part I - Background Information
Definition
The defect is due to antero-cephalad deviation of the outlet septum resulting in: (1) an unrestricted large anterior malalignment subaortic VSD; (2) right ventricular outflow tract obstruction which may be infundibular, valvar, supravalvar or a combination of all; (3) consequent right ventricular hypertrophy; and (4) an overriding aorta (< 50%). Accompanying features can include additional muscular VSDs, anomalous coronary arteries, a right-sided aortic arch, PDA, aortic root dilation, and aortopulmonary collaterals (mainly seen in patients with pulmonary atresia/VSD, which is not discussed here).
The so-called pentalogy of Fallot also has an ASD or PFO.
Approximately 15% of patients with tetralogy of Fallot have a deletion of chromosome 22q11 (97).The incidence is especially high in patients with right aortic arch, pulmonary atresia and aortic-to-pulmonary collaterals. The clinical spectrum is summarized in the 22q11 deletion syndrome (Cardiac defect, Abnormal facies, Thymic hypoplasia, Cleft palate, Hypocalcemia and 22q11 deletion). These patients may have an elevated risk of late psychiatric disorders. Deletion of 22q11 is usually sporadic. Affected subjects, however, have a 50% risk (autosomal dominant) of transmitting the deletion to their offspring.
The pathophysiology varies depending on the degree of right ventricular outflow obstruction.
With relatively mild obstruction, the presentation is of increased pulmonary blood flow and minimal cyanosis, so-called "pink tetralogy" or "acyanotic Fallot". This occasionally presents in adulthood.
Most children, however, have significant RVOT obstruction with consequent right-to-left shunt and cyanosis. Most of them will have had reparative surgery.
Rarely, adults present who are unoperated. For them, surgical repair is still recommended since the results are gratifying and the operative risk is comparable to pediatric series (provided there is good left ventricular function and no serious co-existing morbidity) (98,99).
Some patients reach adulthood with previous palliation only. The types of palliative procedures include:
- Blalock-Taussig shunt or modification (subclavian artery-to-pulmonary artery shunt).
- Waterston shunt (ascending aorta-to-right pulmonary artery).
- Potts shunt (descending aorta-to-left pulmonary artery).
- Central interposition tube graft.
- Infundibular resection (Brock procedure) or pulmonary valvotomy.
- RV-to-PA conduit without VSD closure or with fenestrated closure.
Reparative surgery involves closing the ventricular septal defect and relieving the RVOT obstruction. The latter may involve:
- Resection of infundibular muscle.
- Right ventricular subannular outflow tract patch.
- Transannular patch (a patch across the pulmonary valve annulus which disrupts the integrity of the pulmonary valve and causes substantial pulmonary regurgitation).
- An extracardiac conduit placed between the right ventricle and pulmonary artery (in cases of anomalous coronary artery crossing the RVOT).
- Replacement of the pulmonary valve.
- Pulmonary valvotomy
- Pulmonary arterioplasty.
A patent foramen ovale or secundum ASD should be closed and an AVSD repaired if present.
Additional lesions such as aortic regurgitation or muscular VSDs may also need to be addressed.
Investigations are directed toward the postoperative sequelae and will vary according to the type of operation performed.
All patients should have, at a minimum:
- A thorough clinical assessment.
- ECG.
- Chest x-ray.
- Echo Doppler examination by an appropriately trained individual to detect and quantify residual pulmonary stenosis and regurgitation, residual VSD, right and left ventricular size and function, aortic regurgitation, and aortic root size.
and may require:
- Exercise testing to assess functional capacity and to evaluate possible exertional arrhythmias.
- Holter monitoring.
- Quantitative lung perfusion scan in patients with suspected pulmonary artery branch stenosis.
- Heart catheterization if adequate assessment of the hemodynamics is not obtainable by non-invasive means, including pulmonary angiography in patients with suspected pulmonary artery branch stenosis and coronary angiography if surgical re-intervention is planned.
- EPS for those being evaluated because of sustained atrial flutter or fibrillation, or for sustained monomorphic ventricular tachycardia or fibrillation.
- MRI for the assessment of pulmonary artery or aortic anomalies, pulmonary regurgitant fraction as well as right ventricular size and function.
For those patients who have had previous palliation, assessment of pulmonary artery pressure and anatomy is mandatory at some point, since these shunts have inherent complications (distortion of the pulmonary arteries, stenosis or aneurysm in the shunt or at the site of anastomosis, development of pulmonary hypertension, and volume overloading of the left heart).
The following issues may need to be addressed following a palliative shunt:
- Determine whether complete repair is possible.
- Explain increasing cyanosis with erythrocytosis.
- Determine if pulmonary hypertension is present (unilateral or bilateral).
- Explain the reduction or absence of the continuous shunt murmur (suspected shunt stenosis or occlusion).
- Determine if there is aneurysm formation in the shunt.
Following palliative surgery, complete intracardiac repair should be considered in all patients, in the absence of severe irreversible pulmonary hypertension or unfavourable anatomy (inadequate pulmonary arteries). The following situations particularly warrant complete repair:
|
||
Reoperation is only necessary in approximately 10-15% of patients following reparative surgery over a 20-year follow up.
The following situations may warrant intervention following repair:
|
||
| Patients who require intervention should be operated on by congenital heart surgeons. | ||
The following are possible intervention strategies:
- Surgery may be necessary for residual pulmonary stenosis; this may involve resection of residual infundibular stenosis or placement of an RV outflow or transannular patch. Occasionally a valved extracardiac conduit may be necessary.
- Aortic valve and/or root replacement may be necessary for those with aortic valve regurgitation and/or root dilation.
- Reoperation to insert a new pulmonary valve (either homograft or porcine) may be necessary for severe pulmonary regurgitation leading to right ventricular dilation, sustained arrhythmias and/or symptoms. Tricuspid valve annuloplasty may also be necessary when at least moderate tricuspid regurgitation is present.
- Suture or patch closure of a residual VSD if the shunt is 1.5:1 or if the patient is undergoing cardiac reoperation for other reasons.
- Branch pulmonary artery stenosis may be managed with balloon dilation stent insertion or surgery.
- Radiofrequency or surgical cryoablation for atrial flutter and sustained ventricular tachycardia. Maze procedure including pulmonary vein encirclement for atrial fibrillation.
- The role of AICD for arrhythmias in these patients is unclear.
- Closure of ASD or PFO, especially if there is persistent cyanosis or paradoxical embolus.
The overall survival of patients who have had operative repair is excellent, provided the VSD has been closed and the RVOT obstruction has been relieved. A 36-year survival of 85% has been reported (107). Death may occur from reoperation, endocarditis or congestive heart failure. The cumulative risk of sudden death following repair of tetralogy of Fallot seems to be about 1.2% at 10 years, 2.2% at 20 years, 4% at 25 year and 6% at 35 years (accounting for approximately one third of late deaths) (107,108).
Pulmonary valve replacement for chronic significant pulmonary regurgitation can be performed with a low mortality and may lead to improvement in right ventricular dimension and performance if performed before marked right ventricular dysfunction supervenes (106,109).
Whereas non-sustained ventricular arrhythmia on Holter is common, sustained monomorphic ventricular tachycardia is relatively uncommon. The latter relates to abnormal hemodynamics, usually from RV dilation secondary to pulmonary regurgitation and/or tricuspid regurgitation. QRS duration on the surface ECG correlates to RV size and when prolonged (QRS > 180 ms) is a sensitive (although less specific) predictor of sustained ventricular tachycardia and sudden death (110).
Restoration of hemodynamics through pulmonary valve implantation, tricuspid valve repair, or RVOT aneurysm resection, with concomitant intra-operative cryoablation has a positive effect on pre-existing sustained ventricular tachycardia (106,111). There is clearly a role for antiarrhythmic drugs, but addressing the underlying hemodynamics is usually the top priority. AICD implantation may also have a role for secondary prevention of sudden death; particularly so for patients with advanced ventricular dysfunction, non-responsive to re-operations or without hemodynamic abnormalities amenable to surgery.
Atrial flutter and fibrillation occur in one third of the adult patients and contribute to morbidity and even late mortality (112). As with sustained ventricular tachycardia, restoration of acceptable hemodynamics with concomitant cryoablation and antiarrhythmic medication are the main therapeutic tools (106,111).
Pregnancy in unoperated patients constitutes a considerable risk of maternal and fetal complications and death. This risk is greater when resting oxygen saturations are < 85%. The fall in peripheral resistance during pregnancy and hypotension during labour and delivery may increase the right to left shunt and aggravate pre-existing cyanosis.
The risk of pregnancy in repaired patients depends on the hemodynamic status. The risk is low, approaching that of the general population, in patients with good underlying hemodynamics. In patients with significant residual RVOT obstruction, severe pulmonary regurgitation with or without tricuspid regurgitation and RV dysfunction, the increased volume load of pregnancy may lead to right heart failure and arrhythmias.
All patients with tetralogy should have cardiology counseling pre-conception and follow up by an ACHD cardiologist during pregnancy. Pre-conception assessment of 22q11 deletion syndrome using fluorescent in situ hybridization (FISH) is recommended.
|
All tetralogy patients should have regular cardiology follow up by an ACHD cardiologist.
Endocarditis prophylaxis is recommended. |
||
Section IX - Ebstein Anomaly
Part I - Background Information
Ebstein anomaly is rare. The term encompasses a wide spectrum of anatomic and functional abnormalities of the morphological tricuspid valve (TV) which have certain features in common:
- Apical displacement of the septal and postero-lateral leaflets of the TV below the atrioventricular junction into the right ventricle.
- Resultant 'atrialization' of the inflow of the right ventricle to varying degrees and consequently a smaller 'functional' right ventricle.
- Varying degrees of tricuspid regurgitation (exceptionally, the tricuspid valve is stenotic).
- Enlargement of the right atrium.
- A shunt at atrial level, either PFO or secundum ASD, in approximately 50%.
- One or more accessory conduction pathways, increasing the risk of atrial tachycardias, in 25% of cases.
- Varying degrees of anatomical and physiological right ventricular inflow or outflow tract obstruction.
- Varying impairment of left ventricular function (113-115).
- Varying degrees of cyanosis (less than half the patients).
Associated lesions may include:
- VSD.
- PS.
- Occasionally others, such as aortic coarctation or mitral valve prolapse.
Patients with mild Ebstein anomaly may be asymptomatic with no functional limitation. Survival to the ninth decade has been reported. Patients with moderate Ebstein anomaly may become symptomatic during late adolescence or young adult life. Patients with severe Ebstein usually present at birth or even in utero.
The most common symptoms in adults are exercise intolerance (dyspnea and fatigue) and symptomatic supraventricular arrhythmias. Heart block occasionally occurs.
When an atrial defect is present, patients may be cyanotic (to a varying degree - particularly on exercise), and are at risk of a paradoxical embolus resulting in TIA/stroke. Alternatively, they may have a left-to-right shunt at rest, which can reverse on effort.
End-stage disease with severe tricuspid regurgitation and right ventricular dysfunction may manifest as right-sided cardiac failure. It is usually precipitated by an arrhythmia such as atrial flutter or fibrillation. Sudden death (presumed arrhythmic in nature) may occur at any age, and is more likely if accessory pathway(s) is/are present (116-122).
An adequate diagnostic workup:
- Documents the anatomic severity (degree of apical displacement of the tricuspid valve) with resultant degree of right-sided enlargement, RV dysfunction and degree of tricuspid regurgitation.
- Determines whether the TV has the potential for surgical repair. This depends on the degree of anterior leaflet size and degree of tethering as well as the relative size of the 'functional' RV.
- Documents the presence or absence of an atrial communication and whether there is right-to-left shunting.
- Determines the presence or absence of associated lesions.
- Measures left ventricular function and identifies any mitral valve abnormalities.
- Defines, if possible, the presence or absence of an accessory pathway.
- Determines the amount of functional limitation, if any.
The initial workup should include at a minimum:
- A thorough clinical assessment.
- ECG.
- Chest x-ray.
- Echo Doppler evaluation by an appropriately trained individual.
- Oximetry.
- Exercise test.
- TEE Doppler examination if the anatomic information is not provided by TTE.
- Holter monitor.
- An electrophysiological study if there is a history or ECG evidence of arrhythmias or accessory pathway(s).
- Coronary angiography in patients at risk of coronary artery disease or in patients over the age of 40 years if surgical repair is planned.
The following situations warrant intervention:
|
||
| Ebstein anomaly should only be repaired by congenital heart surgeons, ideally with substantial specific experience in this operation. Every effort should be made to preserve the native tricuspid valve. | ||
When the anterior TV leaflet is mobile and can serve as a monocusp valve, and the functional RV is of adequate size (>1/3 of the total RV), valve repair may be possible and is preferable to valve replacement (130).
If the TV is not repairable, valve replacement will be necessary.
An atrial communication, if present, should be closed.
Given normal PA pressures, in patients with an inadequate RV (because of size or function), severe tricuspid regurgitation and chronic supraventricular arrhythmias, a bi-directional cavopulmonary connection may be used to supplement the intracardiac repair.
Occasionally a Fontan operation may be the best option in patients with tricuspid stenosis and/or hypoplastic RV.
It is controversial whether the atrialized portion of the right ventricle should be plicated to improve hemodynamics and reduce the risk of atrial arrhythmias. Radiofrequency or operative cryoablation have been successful in preventing atrial flutter. A maze procedure including pulmonary vein encirclement may be helpful to prevent and treat atrial fibrillation.
Part VI - Interventional Outcomes
With satisfactory valve repair, with or without bi-directional cavopulmonary connection, medium term prognosis is excellent. Late arrhythmias, most commonly atrial tachyarrhythmias and seldom complete atrioventricular block, may occur (131,132).
Valve re-replacement may be necessary because of a failing bioprosthesis or thrombosed mechanical valve. There is a high incidence of complete heart block with tricuspid valve re-replacement.
In patients with chronic supraventricular arrhythmias (atrial fibrillation/flutter), concomitant cryoablation and/or right atrial maze procedure at the time of surgery may be considered (128). Radiofrequency ablation is less successful because of the commonly very large right atrium.
If an accessory pathway is present, this should be mapped and can be obliterated either at the time of surgical repair or pre-operatively in the catheter laboratory (133). However, multiple pathways are common and pre-operative ablation may prove difficult.
In the absence of maternal cyanosis, right-sided heart failure or arrhythmias, pregnancy is usually well tolerated (134,135).
All Ebstein patients should have regular follow-up with an ACHD cardiologist. Particular attention should be paid to:
Endocarditis prophylaxis is recommended for 6 months following Ebstein repair or for life if any residual gradient/lesions persist or in the presence of prosthetic valve. |
||
Section X - Marfan syndrome
Part I - Background Information
Definition
Marfan syndrome is an autosomal dominantly inherited disorder of connective tissue in which cardiovascular, skeletal, ocular, and other abnormalities may be present to a highly variable degree. Prevalence has been estimated to be 1 in 3000-5000.
New mutations account for 25-30% of cases. The clinical features are the result of a weakening of the supporting tissues, due to defects in fibrillin-1, a glycoprotein and a principal component of the extracellular matrix microfibril. The gene for fibrillin-1 (FBN1) is located on chromosome 15. More than 200 mutations in FBN1 have been described. The phenotype presents to a highly variable degree due to varying genotype expression (136-138).
Prognosis of patients with Marfan syndrome is mainly determined by aortic root abnormalities, which predispose to progressive dilation and dissection, and lead to aortic regurgitation. The mean survival of untreated patients is 40 years, but the variance is large. Not only the aortic root, but also other parts of the aorta and "elastic" arteries may be dilated and may dissect or rupture, but much less commonly. Patients with a dilated aorta are usually asymptomatic. The presence of aortic regurgitation or mitral valve prolapse with regurgitation may lead to signs or symptoms of left ventricular volume overload.
Both medical and surgical therapies have improved life expectancy substantially, from a mean survival of 40 years in 1972 (139) to approximately 60 years in 1993 (140). The risk of type A dissection clearly increases with increasing aortic root diameter. Nonetheless, patients with no or only mild aortic dilation occasionally dissect. A beneficial effect of ß-adrenergic blockade has been shown in slowing the rate of aortic dilation and reducing the risk of dissection (141,142).
| To reduce aortic and arterial stress, the following is recommended: [1] the use of beta-blockade; [2] the avoidance of maximal and isometric exertion, and contact sports. | ||
An adequate diagnostic workup:
- Documents the basis for the diagnosis of Marfan syndrome, using the "Ghent criteria" (143) (see Table 1).
- Determines the diameter and searches for dissection of the aortic root and all other parts of the aorta.
- Determines if aortic regurgitation is present.
- Determines the presence of mitral valve prolapse, mitral regurgitation, calcification of the mitral annulus, presence of tricuspid valve prolapse, tricuspid regurgitation, and the diameter of the main pulmonary artery.
Accuracy of diagnosis is critical, and requires a rigorous approach. To this point, the diagnosis of Marfan syndrome is made on clinical grounds. Because of the variability in clinical expression, a multidisciplinary evaluation in a centre for Marfan screening is recommended for a complete evaluation of a patient and for screening of the patient's relatives for Marfan syndrome.
| A definite diagnosis requires occurrence of major manifestations in two different categories and involvement (presence of criteria) of a third category (see table 1). | ||
When the diagnosis of Marfan syndrome has been established the diagnostic workup should include at a minimum:
- A thorough clinical assessment.
- ECG.
- Chest x-ray.
- Echo-Doppler evaluation especially for measurements of the ascending aorta and degree of mitral regurgitation.
- MRI for measurements of the entire aorta and its branches and for lumbosacral dural ectasia, or abdominal ultrasound for the abdominal aorta; or CT scanning for any of the above.
A diagnostic workup may require:
- Coronary arteriography in patients over the age of 40 years (or younger if there are severe risk factors for coronary artery disease) in whom surgery is being planned.
- Transesophageal echocardiography if aortic dissection is suspected.
Table 1. Diagnostic Criteria for Marfan Syndrome
| Criteria | Major | Minor |
| Family history |
|
|
| Genetics |
|
|
| Cardiovascular |
|
|
| Ocular |
|
(2 needed):
|
| Skeletal (144) | (4 needed):
|
(2-3 major, or 1 major and 2 minor signs):
|
| Skeletal (144) | (4 needed):
|
(2-3 major, or 1 major and 2 minor signs):
|
| Pulmonary |
|
|
| Skin |
|
|
| Central nervous system (144,145) | lumbosacral dural ectasia (CT or MRI) |
The following situations warrant surgical intervention:
|
||
For aortic root replacement the surgical options include: [1] a composite graft repair (modified Bentall procedure - using a mechanical, bioprosthetic, or homograft aortic valve prosthesis) (146); [2] an aortic valve-sparing procedure (150). If necessary, all other parts of the aorta can be replaced. Surgery should be performed in a centre and by surgeons with substantial experience with these types of surgery.
Five and 10 year survival after aortic root replacement is 80% and 60% respectively (148). This relatively poor outlook is mainly caused by the necessity for re-operation of the aorta because of the presence of pre-existing type 1 dissection, or development of new dilation or dissection of other parts of the aorta. A recent study reports a high survival rate at 5 years for selected Marfan patients who had aortic-valve sparing surgery (150). Longer term data is not yet available.
These are not a feature of Marfan syndrome itself. They may occur as a consequence of mitral regurgitation, myocardial ischemia/infarction due to dissection, or ventricular dysfunction.
For women with Marfan syndrome, pregnancy presents a two-fold problem: [1] the genetic problem (a 50% chance that the child will be affected), and [2], an increased (but unquantified) risk of aortic dissection during pregnancy and for up to 6 months post-partum.
| Women with an aortic diameter above 44 mm should be strongly discouraged from becoming pregnant without repair. An aortic diameter below 40 mm rarely presents a problem, although a completely safe diameter does not exist. | ||
|
Whenever possible, Marfan patients should be under the care of professionals with specific training/experience in Marfan syndrome. Ideally, this should be through a multidisciplinary clinic.
All patients with Marfan syndrome should be advised to take beta-adrenergic blocking agents, and to remain on them unless intolerable side effects preclude their use. This is especially true, usually in association with other BP lowering agents, if dissection has occurred. During follow-up the aortic root and the entire aorta should be regularly evaluated with echocardiography, MRI, CT and/or abdominal ultrasound examinations. This is particularly true if a dissection remains and its stability is being monitored. Patients with mitral valve prolapse and moderate mitral regurgitation should also be followed with yearly echocardiography. Endocarditis prophylaxis is recommended for 6 months following aortic root replacement or for life if any residual gradient/lesions persist or in the presence of prosthetic valve or mitral regurgitation. |
||
Bibliography
51. de Sa M, Moshkovitz Y, Butany J, David TE. Histologic abnormalities of the ascending aorta and pulmonary trunk in patients with bicuspid aortic valve: clinical relevance to the Ross procedure. J Thor Cardiovasc Surg 1999;118:588-94.
52. Nistri S, Sorbo MD, Marin M, Palisi M, Scognamiglio R, Thiene G. Aortic root dilation in young men with normally functioning bicuspid aortic valves. Heart 1999;82:19-22.
53. Kirklin JW, Barratt-Boyes BG. Cardiac surgery. 2nd ed. New York: Churchill Livingstone; 1993; 32, Congenital aortic stenosis. p. 1231
54. Keane JF, Driscoll DJ, Gersony WM, Hayes CJ, Kidd L, O'Fallon WM, Pieroni DR, Wolfe R, Weidman WH. Second natural history study of congenital heart defects: Results of treatment of patients with aortic valvar stenosis. Circulation 1996;87(2):I-16-27.
55. Ross JJ, Braunwald E. Aortic stenosis. Circulation 1968;38(Suppl):V61-7.
56. Kelly TA, Rothbart RM, Cooper CM, Kaiser DL, Smucker ML, Gibson RS. Comparison of outcome of asymptomatic to symptomatic patients older than 20 years of age with valvular aortic stenosis. Am J Cardiol 1988;61:123-30.
57. Pellikka PA, Nishimura RA, Bailey KR, Tajik AJ. The natural history of adults with asymptotic, hemodynamically significant aortic stenosis. J Am Coll Cardiol 1990;15:1012-7.
58. Chizner MA, Pearle DL, deLeon AC. The natural history of aortic stenosis in adults. Am Heart J 1980;99(4):419-24.
59. ACC/AHA guidelines for the management of patients with valvular heart disease. A Report of the American Collage of Cardiology/American Heart Association. Task Force on practice guidelines (Committee on management of patients with valvular heart disease) J Am Coll Cardiol 1998;37:1486-588.
60. Donofrio MT, Engle MA, O'Loughlin JE, Snyder MS, Levin AR, Ehlers KH, Gold J. Congenital aortic regurgitation: natural history and management. J Am Coll Cardiol 1992;20(2):366-72.
61. Beppu S, Suzuki S, Matsuda H, Ohmori F, Nagata S, Miyatake K. Rapidity of progression of aortic stenosis in patients with congenital bicuspid aortic valves. Am J Cardiol 1993;71:322-7.
62. Choi JY, Sullivan ID. Fixed subaortic stenosis: anatomical spectrum and nature of progression. Br Heart J 1991;65:280-6.
63. de Vries AG, Hess J, Witsenberg M, Frohn-Mulder IM, Bogers JJ, Bos E. Management of fixed subaortic stenosis: a retrospective study of 57 cases. J Am Coll Cardiol 1992;19(5):1013-7.
64. Coleman DM, Smallhorn JS, McCrindle BW, Williams WG, Freedom RM. Postoperative follow up of fibromuscular subaortic stenosis. J Am Coll Cardiol 1994;24(5):1558-64.
65. Brauner R, Lacks H, Drinkwater DC, Shvarts O, Eghbali K, Galindo A. Benefits of early surgical repair in fixed subaortic stenosis. J Am Coll Cardiol 1997;30:1835-42.
66. Rohlicek CV, Pino SF, Hosking M, Miro J, Cote JM, Finley J. Natural history and surgical outcomes for isolated discrete subaortic stenosis in children. Heart 1999;82:708-13.
67. Roughneen PT, DeLeon SY, Cetta F, Vitullo DA, Bell TJ, Fisher EA, Blakeman BP, Bakhos M. Modified Konno-Rastan Procedure for subaortic stenosis: indications, operative techniques, and results. Ann Thorac Surg 1998;65:1368-76.
68. Serraf A, Zoghby J, Lacour-Gayet F, Houel R, Belli E, Galletti L, Planche C. Surgical treatment of subaortic stenosis: a seventeen-year experience. J Thorac Cardiovasc Surg 1999:117:669-78
69. Rayburn ST, Netherland DE, Heath BJ. Discrete membranous subaortic stenosis: improved results after resection and myectomy. Ann Thorac Surg 1997;64:105-9
70. David TE, Omran A, Ivanov J, Armstrong S, de Sa MP, Sonnenberg B, Webb G Dilation of the pulmonary autograft after the Ross procedure.J Thorac Cardiovasc Surg 2000;119:210-20.
71. Gatzoulis MA. Ross procedure: The treatment of choice for aortic valve disease? Inter J Cardiol 1999:71:205-6.
72. van Son JA, Schaff HV, Danielson GK, Hagler DJ, Puga FJ. Surgical treatment of discrete and tunnel subaortic stenosis. Late survival and risk of reoperation. Circulation 1993;88:II159-II169.
73. Dore A, Somerville J. Pregnancy in patients with pulmonary autograft valve replacement. Eur Heart J 1997;18:1659-62.
74. Rao TT, Adelman AG, Sermer M, Colman JM. Balloon valvuloplasty for congenital aortic stenosis in pregnancy. Br J Obstet Gynecol 1993;100;1141-2
75. Banning AP, Peason JF, Hall RJ. Role of balloon dilation of the aortic valve in pregnant patients with severe aortic stenosis. Br Heart J 1993;70:544-5.
76. Therrien J, Thorne SA, Wright A, Kilner PJ, Somerville J Repaired coarctation: a "cost-effective" approach to identify complications in adults. J Am Coll Cardiol 2000 Mar 15;35(4):997-1002
77. Campbell M. Natural history of coarctation of the aorta. Br Heart J 1970;32:633-40.
78. Gibbs JL. Treatment options for coarctation of the aorta. Heart 2000;84:11-13.
79. Rao PS, Najjar HN, Mardini MK, Solymar L, Thapar MK. Balloon angioplasty for coarctation of the aorta: immediate and long-term results. [Review]. Am Heart J 1988;115:657-65.
80. Hellenbrand WE, Allen HD, Golinko RJ, Hagler DJ, Lutin W, Kan J. Balloon angioplasty for aortic recoarctation: results of Valvuloplasty and Angioplasty of Congenital Anomalies Registry. Am J Cardiol 1990;65:793-7.
81. Ebeid MR, Prieto LR, Latson LA. Use of balloon-expandable stents for coarctation of the aorta: initial results and intermediate-term follow-up. J Am Coll Cardiol. 1997;30:1847-52
82. Magee AG, Brzezinska-Rajszys G, Qureshi SA, Rosenthal E, Zubrzycka M, Ksiazyk J, Tynan M. Stent implantation for aortic coarctation and recoarctation. Heart 1999;82:600-6.
83. Fawzy ME, Sivanandam V, Pieters F, Stenfadouros MA, Galal O, Dunn B, Kinsara A, Khan B, Al-Halees Z. Long-term effects of balloon angioplasty on systemic hypertension in adolescent and adult patients with coarctation of the aorta. Eur Heart J 1999;20:827-32.
84. Maron BJ, Humphries JO, Rowe RD, Mellits ED. Prognosis of surgically corrected coarctation of the aorta. A 20- year postoperative appraisal. Circulation 1973;47:119-126.
85. Shime J, Mocarski EJ, Hastings D, Webb GD, McLaughlin PR. Congenital heart disease in pregnancy: short- and long-term implications. Am J Obstet Gynecol 1987;156:313-22.
86. Szekely P, Julian DG. Heart disease and pregnancy. [Review]. Current Problems in Cardiology 1979;4:1-74.
87. Whittemore R, Hobbins JC, Engle MA. Pregnancy and its outcome in women with and without surgical treatment of congenital heart disease. Am J Cardiol 1982;50:641-51.
88. Barash PG, Hobbins JC, Hook R, Stansel HC, Jr., Whittemore R, Hehre FW. Management of coarctation of the aorta during pregnancy. J Thorac Cardiovasc Surg 1975;69:781-4.
89. Hayes CJ, Gersony WM, Driscoll DJ, Keane JF, Kidd L, O'Fallon WM, Pieroni DR, Wolfe RR, Weidman WH. Second natural history study of congenital heart defects. Results of treatment of patients with pulmonary valvar stenosis. Circulation 1993;87(suppl l):28-37.
90. Chen CR, Cheng TO, Huang T, Zhou YL, Chen JY, Huang YG, Li HJ. Percutaneous balloon valvuloplasty for pulmonic stenosis in adolescents and adults. N Engl J Med 1996;335:21-5
91. McElhinney DB, Chatterjee KM, Reddy VM. Double-chambered right ventricle presenting in adulthood. Ann Thorac Surg 2000;70:124-741.
92. Bove EL, Kavey RE, Byrum CJ, Sondheimer HM, Blackman MS, Thomas FD. Improved right ventricular function following late pulmonary valve replacement for residual pulmonary insufficiency or stenosis. J Thorac Cardiovasc Surg 1985;90:50-5.
93. Stanger P, Cassidy SC, Girod DA, Kan JS, Lababidi Z, Shapiro SR. Balloon pulmonary valvuloplasty: results of the Valvuloplasty and Angioplasty of Congenital Anomalies Registry. Am J Cardiol 1990;65:775-83.
94. McCrindle BW, Kan JS. Long-term results after balloon pulmonary valvuloplasty. Circulation 1991;83:1915-22.
95. Teupe CH, Burger W, Schrader R, Zeiher AM. Late (five to nine years) follow-up after balloon dilation of valvular pulmonary stenosis in adults. Am J Cardiol 1997;80:240-2
96. Sadr-Ameli MA, Sheikholeslami F, Firoozi I, Azarnik H. Late results of balloon pulmonary valvuloplasty in adults. Am J Cardiol 1998;82:398-400.
97. Goldmuntz E, Clark BJ, Mitchell LE, Jawad AF, Cuneo BF, Reed L, McDonald-McGinn D, Chien P, Feuer J, Zackai EH, Emanuel BS, Driscoll DA. Frequency of 22q11 deletions in patients with conotruncal defects. J Am Coll Cardiol 1998;32:492-8
98. Mohanty SR, Airan B, Bhan A, Sharma R, Kumar AS, Kothari SS, Saxena A, Venugopal P. Adult cyanotic congenital heart disease: surgical experience. Indian Heart J 1999;51:186-92
99. Nollert G, Fischlein T, Bouterwek S, Bohmer C, Dewald O, Kreuzer E, Welz A, Netz H, Klinner W, Reichart B. Long-term results of total repair of tetralogy of Fallot in adulthood: 35 years follow-up in 104 patients corrected at the age of 18 or older. Thoracic & Cardiovascular Surgeon 1997;45:178-181.
100. Murphy JG, Gersh BJ, Mair DD, Fuster V, McGoon MD, Ilstrup DM, McGoon DC, Kirklin JW, Danielson GK. Long-term outcome in patients undergoing surgical repair of tetralogy of Fallot. N Engl J Med 1993;329:593-9.
101. Castaneda AR, Sade RM, Lamberti J, Nicoloff DM. Reoperation for residual defects after repair of tetralogy of Fallot. Surgery 1974;76:1010-7.
102. Finck SJ, Puga FJ, Danielson GK. Pulmonary valve insertion during reoperation for tetralogy of Fallot. Ann Thorac Surg 1988;45:610-3.
103. Bonow RO, Lakatos E, Maron BJ, Epstein SE. Serial long-term assessment of the natural history of asymptomatic patients with chronic aortic regurgitation and normal left ventricular systolic function. Circulation 1991;84(4):1625-35.
104. Rosenthal A, Gross RE, Pasternac A. Aneurysms of right ventricular outflow patches. J Thorac Cardiovasc Surg 1972;63:735-40.
105. Downar E, Harris L, Kimber S, Mickleborough L, Williams W, Sevaptsidis E, Masse S, Chen TC, Chan A, Genga A, et al. Ventricular tachycardia after surgical repair of tetralogy of Fallot: results of intraoperative mapping studies. J Am Coll Cardiol 1992;20:648-55.
106. Oechslin EN, Harrison DA, Harris L, Downar E, Webb GD, Siu SS, Williams WG. Reoperation in adults with repair of tetralogy of Fallot: indications and outcomes. J Thorac Cardiovasc Surg 1999;118:245-51
107. Nollert G, Fischlein T, Bouterwek S, Bohmer C, Klinner W, Reichart B. Long-term survival in patients with repair of tetralogy of Fallot: 36-year follow-up of 490 survivors of the first year after surgical repair. J Am Coll Cardiol 1997;30:1374-83.
108. Silka MJ, Hardy BG, Menashe VD, Morris CD. A population-based prospective evaluation of risk of sudden cardiac death after operation for common congenital heart defects. J Am Coll Cardiol 1998;32:245-51
109. Therrien J, Webb GD, Siu S. Pulmonary Valve Replacement in Adults Late after Repair of Tetralogy of Fallot: Are we Operating too Late? J Am Coll Cardiol 2000;36:1670-5.
110. Gatzoulis MA, Till JA, Somerville J, Redington AN. Mechanoelectrical interaction in tetralogy of Fallot. QRS prolongation relates to right ventricular size and predicts malignant ventricular arrhythmias and sudden death. Circulation 1995;92:231-7
111. Gatzoulis MA, Balaji S, Webber SA, Siu SC, Poile C, Hokanson JS, Rosenthal M, Nakazawa M, Moller JH, Gillette PC, Webb CK, Redington AN. Risk factors for arrhythmia and sudden death in repaired Tetralogy of Fallot: A multi-centre study. Lancet 2000;356:975-81.
112. Roos-Hesselink J, Perlroth MG, McGhie J, Spitaels S. Atrial arrhythmias in adults after repair of tetralogy of Fallot. Correlations with clinical, exercise, and echocardiographic findings. Circulation 1995;91:2214-91.
113. Monibi AA, Neches WH, Lenox CC, Park SC, Mathews RA, Zuberbuhler JR. Left ventricular anomalies associated with Ebstein's malformation of the tricuspid valve. Circulation. 1978;57:303-6.
114. Daliento L, Angelini A, Ho SY, Frexure C, Turrini P, Baratella M, Thiene G, Anderson RH. Angiographic and morphologic features of the left venricle in Ebstein's malformation. Am J Cadiol 1997;80:1051-9.
115. Benson LN, Child JS, Schwaiger M, Perloff JK, Schelbert HR. Left ventricular geometry and function in adults with Ebstein's anomaly of the tricuspid valve. Circulation. 1987;75:353-9.
116. Giuliani ER, Fuster V, Brandenburg RO, Mair DD. Ebstein's anomaly: the clinical features and natural history of Ebstein's anomaly of the tricuspid valve. Mayo Clin Proc. 1979;54:163-73.
117. Celermajer DS, Bull C, Till JA, Cullen S, Vassillikos VP, Sullivan ID, Allan L, Nihoyannopoulos P, Somerville J, Deanfield JE. Ebstein's anomaly: presentation and outcome from fetus to adult. J Am Coll Cardiol. 1994;23:170-6.
118. Attie F, Rosas M, Rijlaarsdam M, Buendia A, Zabal C, Kuri J, Granados N. The adult patient with Ebstein anomaly. Outcome in 72 unoperated patients. Medicine (Baltimore). 2000;79:27-36.
119. Hong YM, Moller JH. Ebstein's anomaly: a long-term study of survival. Am Heart J. 1993;125:1419-24.
120. Radford DJ, Graff RF, Neilson GH. Diagnosis and natural history of Ebstein's anomaly. Br Heart J. 1985;54:517-22.
121. Watson H. Natural history of Ebstein's anomaly of tricuspid valve in childhood and adolescence. An international co-operative study of 505 cases. Br Heart J. 1974;36:417-27.
122. Kumar AE, Fyler DC, Miettinen OS, Nadas AS. Ebstein's anomaly. Clinical profile and natural history. Am J Cardiol. 1971;28:84-95.
123. Danielson GK, Driscoll DJ, Mair DD, Warnes CA, Oliver WC Jr. Operative treatment of Ebstein's anomaly. J Thorac Cardiovasc Surg. 1992;104:1195-202.
124. Gentles TL, Calder AL, Clarkson PM, Neutze JM. Predictors of long-term survival with Ebstein's anomaly of the tricuspid valve. Am J Cardiol. 1992;69:377-81.
125. Hetzer R, Nagdyman N, Ewert P, Weng YG, Alexi-Meskhisvili V, Berger F, Pasic M, Lange PE. A modified repair technique for tricuspid incompetence in Ebstein's anomaly. J Thorac Cardiovasc Surg. 1998;115:857-68.
126. Chauvaud S, Fuzellier JF, Berrebi A, Lajos P, Marino JP, Mihaileanu S,Carpentier A. Bi-directional cavopulmonary shunt associated with ventriculo and valvuloplasty in Ebstein's anomaly: benefits in high risk patients. Eur J Cardiothorac Surg. 1998;13:514-9.
127. Carpentier A, Chauvaud S, Mace L, Relland J, Mihaileanu S, Marino JP, Abry B, Guibourt P. A new reconstructive operation for Ebstein's anomaly of the tricuspid valve. J Thorac Cardiovasc Surg. 1988;96:92-101.
128. Theodoro DA, Danielson GK, Porter CJ, Warnes CA. Right-sided maze procedure for right atrial arrhythmias in congenital heart disease. Ann Thorac Surg. 1998;65:149-53; discussion 153-4.
129. van Son JA, Kinzel P, Mohr FW. Pericardial patch augmentation of anterior tricuspid leaflet in Ebstein's anomaly. Ann Thorac Surg. 1998;66:1831-2.
130. Shiina A, Seward JB, Tajik AJ, Hagler DJ, Danielson GK. Two-dimensional echocardiographic--surgical correlation in Ebstein's anomaly: preoperative determination of patients requiring tricuspid valve plication vs replacement. Circulation 1983;68:534-544.
131. Kiziltan HT, Theodoro DA, Warnes CA, O'Leary PW, Anderson BJ, Danielson GK.Late results of bioprosthetic tricuspid valve replacement in Ebstein's anomaly. Ann Thorac Surg. 1998;66:1539-45.
132. Augustin N, Schmidt-Habelmann P, Wottke M, Meisner H, Sebening F. Results after surgical repair of Ebstein's anomaly. Ann Thorac Surg. 1997;63:1650-6.
133. Smith WM, Gallagher JJ, Kerr CR, Sealy WC, Kasell JH, Benson DW Jr, Reiter MJ, Sterba R, Grant AO. The electrophysiologic basis and management of symptomatic recurrent tachycardia in patients with Ebstein's anomaly of the tricuspid valve. Am J Cardiol. 1982;49:1223-34.
134. Donnelly JE, Brown JM, Radford DJ. Pregnancy outcome and Ebstein's anomaly. Br Heart J. 1991;66:368-71.
135. Connolly HM, Warnes CA. Ebstein's anomaly: outcome of pregnancy. JACC 1994;23:1194-98
136. Maron BJ, Moller JH, Seidman CE, Vincent GM, Dietz HC, Moss AJ, Towbin JA, Sondheimer HM, Pyeritz RE, Epstein AE. Impact of laboratory molecular diagnosis on contemporary diagnostic criteria for genetically transmitted cardiovascular diseases: hypertrophic cardiomyopathy, long QT syndrome and Marfan syndrome. Circulation 1998;98:1460-71.
137. Robinson PN, Godfrey M. The molecular genetics of Marfan syndrome and related fibrillinopathies. J Med Genet 2000;37:9-25.
138. Burn J, Camm J, Davies MJ, et al. The phenotype/genotype relation and the current status of genetic screening in hypertrophic cardiomyopathy, Marfan syndrome, and the long QT syndrome. Heart 1997;78:110-6.
139. Murdoch JL, Walker BA, Halpern BL et al: Life expectancy and causes of death in the Marfan syndrome. N Engl J Med 1992;286:804-8.
140. Silverman DI, Burton KJ, Gray J et al. Life expectancy in the Marfan syndrome. Am J Cardiol 1995;75:157-60.
141. Pyeritz RE. Effectiveness of beta-adrenergic blockade in the Marfan syndrome: Experience over 10 years. Am J Med Genet 1989;32: 345.
142. Shores J, Berger KR, Murphy EA, Pyeritz RE. Chronic ß-adrenergic blockade protects the aorta in the Marfan syndrome: a prospective, randomized trial of propranolol. N Engl J Med 1994;330:1335-41.
143. De Paepe A, Devereux RB, Dietz HC, Hennekam RCM, Pyeritz RE. Revised diagnostic criteria for the Marfan syndrome. Am J Med Genet 1996;62:417-26.
144. Sponseller PD, Hobbs W, Riley LH III, Pyeritz RE. The thoracolumbar spine in Marfan syndrome. J Bone Joint Surg 1995; 77A:867-76.
145. Fattori R. Nienaber CA. Descovich B. Ambrosetto P. Reggiani LB. Pepe G. Kaufmann U. Negrini E. von Kodolitsch Y. Gensini GF. Importance of dural ectasia in phenotypic assessment of Marfan's syndrome. Lancet. 354(9182):910-3, 1999 Sep 11.
146. Gott VL, Pyeritz RE, Cameron DE, Greene PS, McKusick VA. Composite graft repair of Marfan aneurysms of the ascending aorta: results in 100 patients. Ann Thorac Surg 1991;52:38-45.
147. Groenink M, Lohuis TAJ, Tijssen JPG, Naeff MSJ, Hennekam RCM, van der Wall EE, Mulder BJM. Survival and complication/free survival in Marfan's syndrome: implications of current guidelines. Heart 1999;82:499-504.
148. Gott VL, Greene PS, Alejo DE, Cameron DE, Naftel DC, Miller DC, Gillinov AM, Laschinger JC, Pyeritz RE. Replacement of the Aortic root in patients with Marfan's syndrome. N Engl J Med 1999;340:1307-13.
149. Finkbohner R, Johnston D, Crawford ES, Coselli J, Milewicz DM. Marfan syndrome. Long-term survival and complication after aortic aneurysm repair. Circulation 1995;91:728-33.
150. Tambeur L, David TE, Unger M, Armstrong S, Ivanov J, Webb G. Results of surgery for aortic root aneurysm in patients with the Marfan syndrome. Eur J Cardiothoracic Surg 2000;17:415-19
151. Pyeritz RE: Maternal and fetal complications of pregnancy in the Marfan syndrome. Am J Cardiol 1981;7:784-90.
152. Rossiter JP, Morales AJ, Repke JT, Murphy EA, Pyeritz RE. A prospective longitudinal evaluation of pregnancy in the Marfan syndrome. Am J Obstet Gynecol 1995;173:1599-606.