RECOMMENDATIONS FOR THE MANAGEMENT OF ADULTS WITH CONGENITAL HEART DISEASE - 2001 (PART 1)
1 | 2 | 3 Click here to view other parts.
- Introduction
- General Recommendations
- Atrial Septal Defect (Section 1)
- Ventricular Septal Defect (Section 2)
- Atrioventricular Septal Defect (Section 3)
- Patent Ductus Arteriosus (Section 4)
- Appendix I
- Appendix II
- Appendix III
- Appendix IV
- Appendix V
- Appendix VI
- Bibliography
INTRODUCTION
We, the authors of this second Consensus Conference Report on Adult Congenital Heart Disease (ACHD), are grateful to the Canadian Cardiovascular Society (CCS) and its Council for the opportunity to update and assemble the document which follows.
Important advances have been made in the field of adult congenital cardiology since the 1996 (1) Consensus Conference Report was published, which led to the decision to provide an update to the recommendations. As well, over 160 new references have been added. Sections on Marfan syndrome, Single Ventricle, and Cyanotic Patients have been added. Prevalence, genetics, pregnancy, and arrhythmias for each specific cardiac lesion have been incorporated. The recommendations which follow are the best available given present knowledge.
These recommendations have been written for cardiologists, cardiac surgeons, and other health care professionals who are not experts in this field. This is important to state, since an audience more or less knowledgeable about the subject would require a different amount of background information and depth of treatment of the material.
We panellists are convinced that the interests of any but the most simple patients are best served by involving what we call "national or regional ACHD centres". The knowledge and experience in the care of these patients should be focused, so that competence and skills become available as quickly as possible. This recommendation is not intended to stand in the way of involving local physicians in the care of these patients as collaborating members of a team with the best interests of the patients at heart. Almost all these patients require primary care. Many would benefit from periodic contact with a cardiologist in their community, along with their specialist at the national or regional ACHD centre.
One of the problems and challenges of ACHD is the large number of different lesions and situations one may encounter. Those of us specializing in the area have worked hard to attain the competence and confidence we have, yet regularly continue to be unclear about managing individual patients. We have great respect for the seemingly endless scenarios we encounter.
Patients with congenital heart disease (CHD) are interesting to have in one's practice, but this should be done either collaboratively with a national or regional ACHD centre, or after one has concluded that the patient does not need such a referral. The natural interest in "collecting a few congenitals" should be resisted until this test has been run. This principle applies as much in a surgical as a medical practice.
Canada is fortunate to have a nation-wide group of national and regional ACHD centres called the CACH Network (see Appendix IV). We encourage Canadian readers to make use of these facilities and the skills and experience they represent. More information can be obtained on the Internet at www.cachnet.org.
Another aspect of this consensus conference update is that it will remain available on the Internet at www.cachnet.org and at www.achd-library.com.
In keeping with the origins of the panellists, this document has been endorsed by the most important societies with an interest in this field (see opening page).
We have written this material in as user-friendly a fashion as possible. We envisaged a clinician looking up a lesion, and wishing to see the recommendations "at a glance", rather than having to refer to other sections of the report. This has led to some repetition for the reader who begins at the beginning, and ends at the end. The repetitive portions are printed in italics to reduce frustrations resulting from this style.
We also committed to NOT writing a textbook, even though a good and current one is needed for an audience such as ours. We have focused on the principles of management of these patients, leaving latitude where possible for the clinician to exercise judgement. We wish to guide, but not to constrain unduly.
We have given weight to our management recommendations. The scales which we used are shown in Appendix III. We have used standards similar to those used in past CCS Consensus Conferences.
We hope these recommendations will be found helpful to the patients in whose interests we have written them, and to those who care for them. Canadians have made important contributions to the management of patients with CHD. We join with our international colleagues in hoping this report will follow in this tradition.
Choice of Panellists
The CCS invited Dr. Gary Webb (president of the Canadian Adult Congenital Heart Network) and Dr. Judith Therrien to lead the process, and endorsed the membership of the primary and secondary panels. As is apparent from the panel memberships, the Grown-Up Congenital Heart Working Group of the European Society of Cardiology and the International Society for Adult Congenital Cardiac Disease contributed many members to this process. While published in Canada, this is truly an international document. Further, the panels were selected so as receive input from various interested groups (adult/pediatric cardiology, cardiac surgery, obstetrics, genetics, nurse practitioner), the various regions of Canada, the United States, Europe and Japan.
Most of the panellists worked very hard reviewing many drafts, and offering suggestions for improvement. The panel had almost no difficulty in reaching agreement on the statements made. Debate occurred only where there was insufficient data to decide a point.
A glossary defining the many unusual terms used in this field has been prepared as a companion document. Space will not permit our publishing this in this journal. We refer you to Adult Congenital Heart Disease Glossary.
GENERAL RECOMMENDATIONS
Part I - Levels of Care for Adult Patients with Congenital Heart Disease
Care should be available at several different levels.
A national ACHD centre is one that can provide all needed services to ACHD patients. The CACH Network has recommended the maintenance or establishment of five 'national' centres in Canada (population 31 million), one in each of the five regions of the country.
A regional ACHD centre is one that has the essential resources required for an ACHD centre (two ACHD cardiologists and excellent echo facilities), plus any other resources they may have beyond this. Such centres would provide most patient care, but would refer to a national centre when their resources are required (e.g. congenital heart surgery; special electrophysiology services).
A national "full service" ACHD centre
- Should have all (or almost all) of the components described below in the ideal national centre.
- May provide care to any patient with congenital or heritable cardiovascular disease.
- Would usually serve a population base of 3-10 million.
- Beyond this, other components of the national ACHD centre described below may be available, depending on local resources and needs.
- May provide care to any patient with congenital or heritable cardiovascular disease within the constraints of available resources.
- Would usually serve a population base of up to 2 million.
- Provides specialist care to the types of patients listed in Appendix I without there being a need to involve an ACHD centre. When such patients require special interventions [e.g. cardiac surgery, electrophysiology study (EPS)], referral to an national or regional ACHD centre is still recommended, unless these matters have nothing to do with the CHD.
- Participates in the care of the types of patients listed in Appendix II in collaboration with the staff of a regional or national ACHD centre.
- May reasonably provide cardiovascular follow up for some of these patients (see categories with asterisks in Appendix I) without specialist referral unless circumstances warrant.
- Should only manage other patients with congenital and heritable cardiovascular disease in collaboration with the staff in a regional or national ACHD centre.
Purpose:
- To optimize care for all adult patients with CHD and to reduce errors in care occurring in such patients.
- To consolidate specialized resources required for the care of adult congenital cardiac patients.
- To provide sufficient patient numbers to facilitate the training of personnel wishing to develop expertise in ACHD, and to maintain staff and faculty competence and special skills in the treatment of patients with ACHD.
- To facilitate research in this unique population in order to approach the ideal of evidence-based care, and to promote a more complete understanding of the processes affecting these patients.
- To offer educational opportunities to primary caregivers, cardiologists and surgeons so that they may contribute optimally to patient management.
- To provide a readily available source of information and expert opinion for patients and doctors.
- To help organize support groups for patients.
- To provide information for government and act as the representative of the specialty.
Human Resources
These should include the following personnel, who have additional experience/training in the management of adults with CHD, as well as adult cardiology in general, and knowledge of the terminology and issues of concern in pediatric CHD patients:
- Two or more cardiologists trained in adult cardiology and/or pediatric cardiology and with special training/experience in the care of ACHD patients.
- At least two surgeons with experience in all aspects of CHD surgery (usually based in a pediatric unit).
- Two or more electrophysiologists with training/experience in congenital cardiac electrophysiology and with relevant pacemaker expertise.
- Two or more interventional cardiologists with training/experience in non-coronary interventional procedures.
- Two or more medical imaging specialists (e.g. MRI, CT, nuclear cardiology).
- Two or more cardiac anesthetists with special ACHD knowledge and skills.
- A well-functioning intensive care team.
- A well-functioning transplant team or a formal association with a transplant centre.
- A social work and vocational counselling service.
- Specialized nursing staff (e.g. nurse clinicians or specialists) with experience in dealing with CHD and adult cardiology.
- A cardiac pathologist with substantial experience in congenital heart malformations.
- Consultants in the fields of obstetrics and gynecology, genetics, nephrology, pulmonary medicine, hematology, neurology, rheumatology, cardiac rehabilitation, infectious diseases and psychiatry/psychology.
The following resources should be available:
- Echocardiography (including transesophageal, intra-operative, and fetal echocardiography).
- A cardiac catheterization laboratory with biplane angiography for both diagnostic and interventional procedures.
- An electrophysiology laboratory capable of sophisticated mapping and radiofrequency ablation.
- An operating room and team capable of providing both pump and non-pump facilities, both electively and as emergencies.
- Other appropriate inpatient facilities [intensive care unit (ICU), step-down and inpatient unit].
- Diagnostic imaging with full capabilities (including cardiovascular radiology, computerized tomography, magnetic resonance imaging, nuclear cardiology).
- Pacemaker clinic with expertise in advanced pacing and defibrillation technology.
- Holter monitoring.
- Cardiopulmonary function testing, exercise testing, and oxygen saturation capability.
- Cardiac pathology.
- Data collection system.
- To provide optimal care to adults with CHD.
- To work with colleagues at the usually adjacent pediatric centres to optimize the transition and transfer of patient care from a pediatric to an adult facility.
- To hold regular conferences in which management of patients is discussed and decisions are made through consensus.
- To ensure appropriate and timely communication with referring physicians and their staff.
- To ensure appropriate links between the national ACHD centre and support services within the academic medical centre.
- To implement and ensure processes for evaluating feedback and continuous quality improvement in patient care and teaching within the national ACHD centre.
- To ensure co-operation and collaboration with other ACHD centres.
- To participate in clinical trials with other centres both nationally and internationally, and to help develop new knowledge through, when appropriate, the sharing of linked databases established in accordance with legal and ethical requirements.
- To establish and evaluate ongoing training programs both for cardiologists and surgeons interested in developing expertise in the treatment of patients with ACHD, and for all associated staff, including technologists, nurses, psychologists, physiotherapists, occupational therapists and others.
- To maintain a database on all patients managed through that centre.
Part III - Indications for Referral to an National or Regional ACHD Centre
An adult or older adolescent patient would be referred to an ACHD centre for:
- Assessment of suspected or known CHD.
- Follow up and continuing care of patients with lesions listed in Appendix II.
- Some types of surgical/non-surgical intervention.
- Assessment regarding non-cardiac surgery or pregnancy.
Part IV - Specialists Involved in the Management of ACHD Patients
Cardiac surgeons operating on adults and adolescents with CHD should have completed training in cardiothoracic or cardiac surgery to prevailing national standards, undergone formal training in surgery for congenital heart malformations, and obtained extensive experience in surgical management of adult patients with CHD.
Cardiac anesthetists involved in surgery on adults with CHD must have had specialized training and/or extensive experience in the treatment of patients with CHD, adult patients undergoing other types of cardiac surgery and the anesthetic management of problems such as cyanosis, elevated pulmonary vascular resistance, or severe outflow obstruction.
Adult ACHD cardiologists (especially those still to-be-trained) should have completed full adult cardiology training, and have taken at least one year of supplemental training in CHD as it applies to adolescents and adults. Guidelines have been published. Their ability to serve the interests of these patients will be in proportion to the amount of time they have spent in training, continuing education, and clinical experience in the management of these patients.
Pediatric ACHD cardiologists (especially those still to-be-trained) should have completed pediatric cardiology training, and have taken at least one year of supplemental training in adult cardiology and ACHD so as to be able to recognize and deal with non-congenital issues that will arise in these patients. Their ability to serve the interests of these patients will be in proportion to the amount of time they have spent in training, continuing education, and clinical experience in the management of these patients.
Echocardiographers responsible for recording and interpreting echocardiograms in adults with CHD should be appropriately trained (level 3 echocardiography training) and have a thorough understanding of the technical principles of echocardiography and a thorough knowledge of the anatomy, hemodynamics and pathology of both acquired and CHD in order to obtain, correlate, and record efficiently the echocardiographic findings. The Canadian Society of Echocardiography on Physician Training recommends 1 year of echocardiography fellowship to attain level 3 training (2). Training in transesophageal echocardiography is also vital.
Part V - Specific Issues in the Care of Patients with ACHD
Non-cardiac Surgery
Performance of any surgical procedures in most adult patients with CHD carries a greater risk than in the general population. Evaluation in an ACHD centre prior to surgery is recommended, and in the case of unoperated or complex ACHD, it is recommended (where feasible) that the surgery be carried out in the ACHD centre, utilizing experienced cardiac anesthetists. This is strongly recommended for cyanotic patients, patients with pulmonary hypertension, or with some rhythm abnormalities. Pregnant women with CHD should be managed by the patient's obstetrician and ACHD cardiologist together with a cardiac anesthetist if necessary. In most cases, an obstetrician knowledgeable in the management of ACHD is optimal. Postoperatively, the patients with CHD may need ICU/monitoring facilities even for relatively minor procedures.
Dental Care
Regular dental care, often in a hospital setting, is needed by most adult patients with CHD to decrease the likelihood of caries, abscesses or periodontal disease, all of which contribute to the increased incidence of infective endocarditis. There is justification for government subsidization of dental care in those patients unable to afford it. Endocarditis prophylaxis, both antibiotics and daily teeth/gum care, are recommended.
Informed Consent
Despite its lifelong presence, most adolescents and young adults with CHD have inadequate knowledge about their cardiac conditions. Health care providers must assess each patient's knowledge of his or her condition and give appropriate information to enable independent decision-making about choices in care. Adults with CHD should be encouraged to understand not only their disease, but the medications they use. They should be involved in major management decisions or decisions involving invasive procedures. Patients should be encouraged to inform their specialists of any new events which may occur. Further involvement of patients in the evaluation of processes, programs, and in the planning of research trials within the constraints of their motivation and capacity to understand them is ideal.
Advance Directives and Palliative Care
Patients should be made aware of the availability of advance directives which are legally binding. Their use may reduce uncertainty when caring for critically ill individuals. Likewise the role of non-intervention, or of palliative care, as a treatment modality should be presented in a realistic, unbiased, and acceptable manner as one of the options to patients making decisions about interventions or procedures. The probable result of this clinical pathway should be objectively explained with comparison of outcomes with other interventions when this information is known.
Auto-Donation of Blood
Patients should be made aware of the possibility of autologous donation or directed donation (from family members) of blood prior to cardiac surgery if such facilities exist.
SECTION I - ATRIAL SEPTAL DEFECT
Part I - Background Information
Atrial septal defect (ASD) includes the following types: ostium secundum, sinus venosus and coronary sinus. Ostium primum [partial atrioventricular septal defect (AVSD)] is discussed in Section III.
A "clinically significant" ASD:
- Causes right heart volume and sometimes pressure overload.
- May cause exercise limitation.
- May be associated with atrial arrhythmias (atrial fibrillation, atrial flutter, usually over age 30).
- May cause late right heart failure (usually over age 40).
- May permit paradoxical embolism resulting in TIA/stroke.
- May lead to pulmonary hypertension, although pulmonary hypertension may also develop from other causes.
Although usually sporadic, some ASDs are inherited as an autosomal dominant and/or are associated with other congenital lesions e.g. Holt-Oram syndrome.
Part III - History and Management of Unoperated Patients
Most patients with "significant" ASDs (see above) will eventually develop symptoms, although the timing of symptom development is unpredictable and may be after the 5th decade.
The most common symptoms are exercise intolerance (dyspnea and fatigue) and symptomatic supraventricular arrhythmias (atrial fibrillation, atrial flutter, or sick sinus syndrome).
Any condition causing reduced left ventricular compliance (e.g. left ventricular hypertrophy due to hypertension, cardiomyopathy or myocardial infarction) will tend to increase the left-to-right shunt through an ASD and worsen symptoms. Their prevention and/or early treatment should be addressed.
In Lutembacher syndrome (congenital ASD with acquired mitral stenosis), the mitral valve obstruction increases the left-to-right shunt. The combination of lesions is usually poorly tolerated.
Part IV - Diagnostic Recommendations
An adequate diagnostic workup:
- Documents the presence and type of ASD(s).
- Determines the size (diameter) of the defect(s).
- Determines the functional importance of the defect either by:
- shunt size (Qp/Qs).
- right ventricular size, function and volume overload and right atrial size
- pulmonary artery pressures and if elevated, pulmonary vascular resistance.
- Identifies other associated conditions that may influence management (e.g. anomalous pulmonary venous connection, significant valve disease; or coronary artery disease).
- A thorough clinical assessment.
- ECG.
- Chest x-ray.
- Transthoracic echo-Doppler evaluation by an appropriately trained individual.
- Transesophageal (TEE) echo/Doppler examination to prove the existence of an ASD, better define its/their location(s) and size(s) and shape(s), assess pulmonary venous connections, and to evaluate the cardiac valves, if this information is not provided by transthoracic echocardiography (TTE). A transesophageal examination is essential to determine if the ASD is suitable for device closure and must be performed prior to the procedure.
- Resting oxygen saturation.
- Heart catheterization (if determination of pulmonary artery pressures and resistances is of concern; to assess pulmonary vascular reactivity; or delineate anomalous pulmonary venous connections).
- Coronary angiography in patients at high risk of coronary artery disease or in patients over the age of 40 years if surgical repair is planned.
- Magnetic resonance imaging (MRI) to prove the existence of an ASD or to assess pulmonary venous connections if doubts remain after other imaging modalities. MRI can also be used to estimate Qp/Qs.
- Oxygen saturation with exercise if there is any suggestion of pulmonary hypertension. If there is severe pulmonary hypertension or resting desaturation of < 85%, the patient should not be exercised.
- Open lung biopsy should only be considered when the reversibility of the pulmonary hypertension is uncertain from the hemodynamic data. It is potentially hazardous and should be done only at centres with substantial relevant experience in CHD.
Indications for closure are debated. There is little proof of firm guidelines. We offer a consensus view.
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The mere presence of a "significant" ASD may warrant intervention especially if there is a significant shunt (> 2:1).
If pulmonary hypertension is present [pulmonary artery pressure (PAP) > 2/3 systemic arterial blood pressure (SABP), or pulmonary arteriolar resistance > 2/3 systemic arteriolar resistance], there must be a net left-to-right shunt of at least 1.5:1; or evidence of pulmonary artery reactivity when challenged with a pulmonary vasodilator (e.g. oxygen, nitric oxide and/or prostaglandins); or lung biopsy evidence that pulmonary arterial changes are potentially reversible (Heath Edwards grade II-III or less). A cryptogenic cerebrovascular event in the presence of a small ASD or PFO and right-to-left shunting demonstrated on contrast echo. This indication is "softer" than the others. |
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If closure of atrial septal defects is being planned, it is recommended that closure be performed without undue delay (< 25 years for mortality benefit, and probably before 40 years for arrhythmia benefit). As a rule, younger patients have a better outlook after repair (3,9,10).
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Transvenous pacing should be avoided in patients with unrepaired ASDs, since paradoxical emboli may occur. For the same reason venous thromboemboli from any source are a potential hazard.
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Part VI - Surgical/Interventional Technical Options
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Device closure may now be offered as an alternative to surgical closure to patients with secundum ASD of up to 36-38 mm in diameter. The intervention should be performed under general anesthesia with transesophageal guidance in centres and by individuals with a commitment to the technique and to its clinical evaluation.
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Surgical closure may also be offered, and may be especially attractive should the patient prefer the time-honoured surgical approach, or especially if atrial arrhythmia surgery (atrial maze procedure for atrial fibrillation and radiofrequency or cryoablation for atrial flutter) may be offered concurrently.
The availability of an inframammary or right mini thoracotomy or mini sternotomy approach to a typical secundum ASD should be made known to potentially interested patients considering surgery.
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Patients with a sinus venosus ASD or ostium primum ASD cannot be closed by percutaneous devices and should be surgically repaired by congenital heart surgeons.
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Part VII - Surgical/Interventional Outcomes
Device closure.
Early and intermediate follow-up is excellent after device closure. The intermediate results are comparable to surgery with a high rate of shunt closure and few major complications. Long-term outcome is unknown. Longer follow-up is needed to determine the incidence of arrhythmias and thromboembolic complications late after device closure.
Functional capacity improves and supraventricular arrhythmias are better tolerated and more responsive to pharmacologic management.
Surgical closure.
For secundum ASD without pulmonary hypertension surgical closure should result in a very low (< 1%) operative mortality. Early and long-term follow-up is excellent.
Following surgical repair, pre-operative symptoms, if any, should decrease or abate. Pre-existing atrial flutter and fibrillation may persist unless cryo- or radiofrequency ablation (for the former) or a right atrial maze including pulmonary vein encirclement (for the latter) has been performed. Likewise, atrial flutter and/or fibrillation may arise de novo after repair, but are better tolerated and often more responsive to antiarrhythmic therapy.
Left ventricular failure may occur in patients with associated cardiovascular disease (e.g. coronary artery disease, hypertension, mitral valve incompetence).
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Post-operative ASD patients are especially prone to cardiac tamponade for the first several weeks after surgery.
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Part VIII - Arrhythmias
Late atrial fibrillation may occur in up to 1/3 of patients, especially in adults older than 40 years and/or if atrial arrhythmias were present pre-operatively. Physicians may elect to anticoagulate these high risk patients with warfarin for the first 6 post-operative months, as they are at risk of atrial fibrillation and stroke. Anticoagulation can probably be discontinued thereafter, if they remain arrhythmia-free and there are no other risk factors.
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The presence of preoperative atrial flutter/fibrillation may warrant surgical closure of the defect with concomitant cryosurgical/ablative therapy or an atrial maze procedure.
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If atrial fibrillation occurs, both anticoagulants and antiarrhythmic therapy are usually indicated.
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Part IX - Pregnancy
Pregnancy is well tolerated in patients after ASD closure. Pregnancy is also well tolerated in women with unrepaired ASDs, but the risk of paradoxical embolism is increased during pregnancy as well as the post partum period.
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Pregnancy is contraindicated in Eisenmenger syndrome because of the high maternal (up to 50%) and fetal (up to 60%) mortality.
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Part X - Follow Up
The following ASD patients require periodic follow up by an ACHD cardiologist.
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SECTION II - VENTRICULAR SEPTAL DEFECT
Part I - Background Information
Only isolated VSDs will be considered.
Hemodynamic Severity Grading of Isolated Ventricular Septal Defects (VSDs) in Adults
| Small: |
Pulmonary/aortic systolic pressure ratio < 0.3, and pulmonary/systemic flow ratio (Qp/Qs) < 1.4 |
| Moderate: | Systolic pressure ratio > 0.3, and Qp/Qs 1.4 to 2.2 |
| Large: | Systolic pressure ratio > 0.3, and Qp/Qs > 2.2 |
| Eisenmenger: | Systolic pressure ratio > 0.9, and Qp/Qs < 1.5 |
Physiological Classification of Isolated VSD in Adults
| Restrictive: | RV pressure < LV pressure in the absence of right ventricular outflow tract obstruction. |
| Non-restrictive: | Equal right and left ventricular pressures in the absence of right ventricular outflow tract obstruction. |
Clinical Severity Grading of Isolated VSDs in Adults
| Small: | Causes negligible hemodynamic changes. LV size is usually normal without any pulmonary hypertension. |
| Moderate: | Causes enlargement of left ventricle and left atrium and usually some pulmonary hypertension (reversible). |
| Large: | Results in pulmonary vascular obstructive disease and Eisenmenger physiology unless there is coexistent right Ventricular outflow tract obstruction. |
Pathologic/ Surgical Classification
| Perimembranous | Bordered by fibrous continuity of an atrioventricular valve and an arterial valve, usually with inlet or outlet extension |
| Muscular | Bordered by muscle rim, usually trabecular |
| Doubly committed | Bordered by fibrous continuity of both the aortic and the pulmonary valve |
| VSDs may co-exist with other cardiac lesions (especially valvar or subvalvar pulmonary stenosis) or result in secondary infundibular hypertrophy, right ventricular outflow obstruction and aortic regurgitation from aortic cusp prolapse. | |
Part II - Prevalence and Genetics
Doubly-committed VSDs are more common in Asian patients.
Part III - History and Management of Unoperated Patients
Small VSDs are associated with a relatively high risk of endocarditis but otherwise patients enjoy a normal life expectancy. Atrial arrhythmias may occur.
Spontaneous closure of VSDs can still occur occasionally in adult life.
Moderate VSDs are unusual in the adult but may occur when a prolapsing aortic valve cusp partially obstructs the defect. They are associated with the development of left heart dilation and shunt-related pulmonary hypertension (which often reverses with correction of the defect), and resultant congestive heart failure and atrial fibrillation, as well as the risk of endocarditis.
Large VSDs without pulmonary hypertension exist in adults only when associated with obstruction to right ventricular outflow and are rare. All such patients are at risk for endocarditis. Some are cyanotic because of more severe right ventricular outflow tract obstruction at the infundibular or valvular level.
VSD patients with Eisenmenger syndrome (see section XV) are at continuous risk of mortality and morbidity. Poor prognostic features are felt to be atrial flutter/fibrillation, syncope, heart failure, hemoptysis and aneurysmal dilation of proximal hypertensive pulmonary arteries which may rupture even with laminated thrombus in such dilated arteries.
Five percent of VSDs develop aortic valve regurgitation. Patients with doubly-committed sub-arterial VSDs are more likely to develop aortic regurgitation from progressive prolapse of the aortic valve cusps than those with a perimembranous VSD (23).
Part IV- Diagnostic Recommendations
An adequate diagnostic workup:
- Documents the number and type(s) of VSD.
- Determines the size (restrictive/non-restrictive) and functional importance (left-to-right shunt estimate; left and right ventricular size/function; ventricular volume and pressure overload; pulmonary artery pressure and resistance) of the defect.
- Identifies other associated conditions that may influence management (aortic regurgitation; subaortic stenosis; right ventricular outflow obstruction; significant valve disease; coronary artery disease; coarctation of the aorta).
- A thorough clinical assessment.
- ECG.
- Chest x-ray.
- Transthoracic echo-Doppler evaluation by an appropriately trained individual.
- Oximetry.
- Heart catheterization (to determine pulmonary artery pressures and resistances [ reversibility using oxygen, nitric oxide and/or prostaglandins]; to assess intracardiac shunting; to evaluate associated lesions, particularly if aortic regurgitation is present; to exclude multiple VSDs).
- Coronary angiography in patients at risk of coronary artery disease or in patients over the age of 40 years if a surgical repair is planned.
- Open lung biopsy should only be considered when the reversibility of the pulmonary hypertension is uncertain from the hemodynamic data. It is potentially hazardous and should be done only at centres with substantial relevant experience in CHD.
- MRI occasionally to confirm the presence or absence of other associated lesions or to help define the anatomy of the aortic cusps to eliminate aortic valve prolapse. MRI can also be used to estimate Qp/Qs.
The following situations warrant operative closure:
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Endocarditis (especially recurrent) may be an indication for operative closure (30).
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Transvenous pacing should be avoided where possible in all patients with VSDs since paradoxical emboli may occur. For the same reason, venous thromboemboli from any source are a potential hazard.
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Part VI - Surgical/Interventional Technical Options
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Patients with an isolated VSD with or without associated lesions (right ventricular outflow tract obstruction, aortic valve prolapse, subaortic stenosis or infective endocarditis) should be repaired by congenital heart surgeons.
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Device closure of VSDs may be performed in the setting of isolated trabecular muscular VSDs but are still considered an experimental procedure for perimembranous VSDs (31,32).
Part VII - Surgical/Interventional Outcomes
Successful closure is associated with excellent survival if ventricular function is normal.
Elevated pulmonary artery pressures preoperatively may progress, regress or remain unchanged post-operatively.
Part VIII - Arrhythmias
Atrial fibrillation may occur, especially if there has been longstanding volume overload of the left heart, or if other reasons for left atrial dilation are present.
Late ventricular arrhythmias and sudden death are a potential risk especially in patients repaired late in life. (33,34).
Complete heart block may also occur after surgical repair.
Part IX - Pregnancy
Pregnancy is well tolerated in women with small or moderate VSD and in women with repaired VSDs.
| Pregnancy is contraindicated in Eisenmenger syndrome because of high maternal (up to 50%) and fetal (up to 60%) mortality. | ||
Part X - Follow Up
Patients with the following problems benefit from periodic evaluation by an ACHD cardiologist:
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SECTION III - ATRIOVENTRICULAR SEPTAL DEFECT
Part I - Background Information
Definition
The terms atrioventricular (septal) defects, atrioventricular canal defects and endocardial cushion defects can be used interchangeably to describe this group of defects. Atrioventricular septal defects (AVSD) cover a spectrum of anomalies caused by abnormal development of the endocardial cushions. The defect may be only at the atrial level (ostium primum ASD) or may include an inlet-type ventricular septal defect (intermediate AVSD when the VSD is restrictive or complete form of AVSD when the VSD is non-restrictive). The atrioventricular valves are fundamentally abnormal being derived from five leaflets (a right antero-superior leaflet, a right inferior leaflet, a superior bridging leaflet, an inferior bridging leaflet and a left mural leaflet). This may result in separate right and left AV valves (with the left AV valve having a "cleft" at the junction of the superior and inferior bridging leaflets) or a common valve. (See classification below)
Classification:
| Partial AVSD: |
The ventricular septum is intact. There is almost always a primum ASD. 'Cleft' in the left AV (mitral) valve. There are two separate AV valve annuli. |
| Intermediate AVSD: |
This is the rarest form and a part of a spectrum between complete and partial AVSD. It is characterized by a restrictive VSD, a primum ASD and a cleft mitral valve. The anterior and posterior bridging leaflets are fused giving 2 distinct AV valve components. |
| Complete AVSD: |
There is a non-restrictive inlet-type VSD. There is usually a primum ASD but rarely the atrial septum may be intact. There is a common AV orifice. |
Part II - Prevalence and Genetics
AVSD may coexist with other lesions, both cardiac and non-cardiac. Down syndrome occurs in 35% of patients with AVSD. Most complete AVSDs occur in Down syndrome patients (> 75%). Patients with Down syndrome have a premature tendency for pulmonary vascular disease irrespective of the type of AVSD. Most partial AVSDs occur in non-Down syndrome patients (> 90%). AVSD may occur in association with tetralogy of Fallot and other forms of complex CHD.
Part III - History and Management of Unoperated Patients
Clinical presentation of these patients will depend on the presence and size of the ASD and VSD and competence of the left AV ("mitral") valve.
Clinical presentation may take several forms:
- Symptoms of heart failure or pulmonary vascular disease.
- Atrial arrhythmias, nodal rhythm, or complete heart block.
- Subaortic stenosis may or may not be present initially but may develop or progress.
- No symptoms.
Presentation of an unrepaired partial (ostium primum ASD) or intermediate AVSD as an adult is not uncommon. Symptoms include decreased exercise tolerance, fatigue, dyspnea, arrhythmias, and recurrent chest infections. Symptoms increase with age and most adults are symptomatic by 40 years of age.
Complete AVSD :
Most patients with complete defects will have been repaired in infancy although some may have been palliated in the past with pulmonary artery bands and have variable degrees of pulmonary vascular obstructive disease. The history of unoperated complete AVSD is that of Eisenmenger syndrome to be discussed in Section XV. AVSD with Eisenmenger syndrome seems to have a worse prognosis than ASD, VSD or PDA with Eisenmenger. Poor prognostic features are felt to be atrial flutter/fibrillation, syncope, heart failure and hemoptysis.
Part IV - Diagnostic Recommendations
An adequate diagnostic workup:
- Documents the presence of each component of the AVSD and whether or not the ventricular chamber sizes are "balanced" (although this is usually a pediatric issue).
- Assesses the magnitude and direction of intracardiac shunting.
- Documents the pulmonary artery pressure.
- Documents abnormalities of the atrioventricular valves and their connections (straddling of the AV vales/overriding of the AV annulus) and assesses the severity of AV valve regurgitation, if any.
- Documents the presence/absence of subaortic stenosis. This may occasionally require provocative testing with isoproterenol although it may be impossible to document a gradient in the presence of a non-restrictive VSD.
- Identifies the presence of associated abnormalities (cardiac and non-cardiac) which may impact upon management (e.g. pulmonary hypertension, tetralogy of Fallot, PDA, muscular VSDs, aortic coarctation or Down syndrome).
- A thorough clinical assessment paying particular attention to AV valve regurgitation.
- ECG.
- Chest x-ray.
- Transthoracic echo-Doppler evaluation by an appropriately trained individual.
- TEE to determine the exact anatomy (if unclear after TTE); the presence of intracardiac shunts; chordal attachments; the presence and severity of left AV ("mitral") valve regurgitation (or stenosis if previous valve repair has been undertaken); the presence and severity of right AV valve regurgitation and subaortic stenosis.
- Heart catheterization to determine: the presence and magnitude of intracardiac shunts; pulmonary artery pressures and resistances; the severity of pulmonary vascular disease (± reversibility using oxygen, nitric oxide and/or prostaglandins); the presence and severity of left AV ("mitral") valve regurgitation (or stenosis, if previous valve repair has been undertaken); the presence and severity of subaortic stenosis (provocative testing may be necessary).
- Coronary angiography in patients at risk of coronary artery disease or in patients over the age of 40 years if a surgical repair is planned.
- Open lung biopsy should only be considered when the reversibility of the pulmonary hypertension is uncertain from the hemodynamic data. It is potentially hazardous and should be done only at centres with substantial relevant experience in CHD.
- Holter monitoring to assess AV block or other arrhythmia.
- MRI to help define the anatomy. MRI can also be used to estimate Qp/Qs.
Part V - Indications for Intervention/Reintervention
The following situations warrant intervention/reintervention:
|
||
| Transvenous pacing should be avoided if there are residual inter-atrial or inter-ventricular communications since paradoxical emboli may occur. For the same reason, venous thromboemboli from any source are a potential hazard. | ||
Part VI - Surgical Technical Options
| AVSD patients, including those with ostium primum ASD, left AV ("mitral") valve repair, subaortic stenosis or residual defects should be operated on by congenital heart surgeons. | ||
When "mitral" valve repair is not possible, "mitral" valve replacement may be necessary. It should have a similar operative risk as routine mitral valve replacement although the risk of complete AV block may be higher.
Part VII - Surgical Outcomes
In the short term, the results of repair of partial AVSD are similar to those following closure of secundum ASD, but sequelae of left AV ("mitral") valve regurgitation, subaortic stenosis and AV block may develop or progress. (38-42)
In general, late results after "mitral" valvuloplasty for these patients have been excellent with the need for surgical revision in about 5-10% of patients. (39-41) Occasionally, repair of the abnormal left AV ("mitral") valve may result in a stenotic valve, which will usually necessitate reoperation.
The likelihood of a residual left-to-right shunt from left atrium or left ventricle to right atrium is small.
Subaortic stenosis will develop or progress in up to 5% of patients after repair, particularly in patients with primum ASD and some complete defects, especially if the left AV (mitral) valve has been replaced.
The long-term results of repair of complete AVSD are not well known but similar problems as with partial AVSD are likely.
Part VIII - Arrhythmias
First degree AV block is common and complete AV block may occur spontaneously or after repair. Sinus node dysfunction may also occur especially after repair and lead to brady- or tachyarrhythmias. Atrial flutter or fibrillation in the adult are not uncommon.
Part IX - Pregnancy
Pregnancy is well tolerated in patients with complete repair and no significant residual lesions.
Women in NYHA class I and II with unoperated partial AVSD usually tolerate pregnancy very well, but have an increased risk of paradoxical embolization.
| Consideration should be given to closure of any significant AVSD prior to pregnancy in order to minimize the risk of paradoxical emboli. | ||
| Pregnancy is contraindicated in Eisenmenger syndrome because of the high maternal (up to 50%) and fetal (up to 60%) mortality. | ||
Part X - Follow Up
|
All patients with AVSD require periodic follow up by an ACHD cardiologist because of the possibility of progressive AV valve regurgitation (or stenosis); the development of subaortic stenosis; the development of significant atrial arrhythmias, or progression of the commonly present 1st degree AV block.
Particular attention should be paid to those with pulmonary vascular disease present pre-operatively. Endocarditis prophylaxis is recommended for 6 months following AVSD closure or for life if any residual defect persists. |
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SECTION IV - PATENT DUCTUS ARTERIOSUS
Part I - Background Information
The ductus arteriosus, in utero, connects the proximal left pulmonary artery to the descending aorta, just distal to the left subclavian artery. Failure of closure at birth represents a congenital malformation. A PDA in adult is usually an isolated lesion.
Clinical Severity Grading of Patent Ductus Arteriosus (PDA) in Adults
| Silent: | Tiny PDA detected only by non-clinical means (usually echo). |
| Small: | Audible continuous murmur. Causes negligible hemodynamic change. Normal LV size without any pulmonary hypertension. |
| Moderate: | Audible continuous murmur. Wide pulse pressure (as in aortic regurgitation). Causes enlargement of the left ventricle and some pulmonary hypertension (usually reversible). |
| Large: | Usually does not exist in adults without Eisenmenger physiology. |
| Eisenmenger: | Continuous murmur is absent. Causes substantial pulmonary hypertension, differential hypoxemia, and often differential cyanosis. |
Part II - History and Management of Unoperated Patients
The risk of endarteritis with small silent PDA is unknown but is likely very low (only sporadic case reports exist).
| No intervention is indicated if a small silent PDA is detected. | ||
All other PDAs are associated with a risk of endarteritis (which may increase with increasing age).
Small PDAs have a normal life expectancy.
A moderate PDA is unusual in the adult. It is associated with the development of left heart dilation and shunt-related pulmonary hypertension (which often reverses with correction of the defect). The majority of patients are symptomatic from dyspnea or palpitations (atrial arrhythmias), although frank heart failure is unusual.
A large PDA is rare in the adult, most having been corrected in infancy and childhood. Pulmonary hypertension is usual and may not reverse entirely with closure of the defect. Most patients are symptomatic from dyspnea or palpitations. Aneurysm formation of the duct is an uncommon but important complication.
Eisenmenger PDA has a similar prognosis to Eisenmenger VSD although symptoms may be less marked and exercise tolerance better. Eisenmenger PDA is further discussed in section XV.
Part III - Diagnostic Recommendations
An initial diagnostic workup:
- Documents the presence of PDA.
- Determines the size (systemic-to-pulmonary shunt estimate) and functional importance (pulmonary artery pressures) of the defect. Shunt estimates are often inaccurate because of the difficulty in obtaining a representative pulmonary blood sample for saturation assessment.
- Identifies whether a ductal aneurysm is present.
- Identifies whether the duct is calcified if surgical repair is planned.
- A thorough clinical assessment.
- ECG.
- Chest x-ray.
- Transthoracic echo-Doppler evaluation by an appropriately trained individual.
- Oximetry (obtained on both fingers and toes).
- Heart catheterization (to determine pulmonary artery pressures and resistances with testing of pulmonary vascular reactivity using prostacyclin, inhaled oxygen and nitric oxide if pulmonary arterial pressures are greater than 2/3 systemic).
- Coronary angiography in patients at risk for coronary artery disease or in patients over 40 years if a surgical repair is planned.
- Open lung biopsy should only be considered when the reversibility of the pulmonary hypertension is uncertain from the hemodynamic data. It is potentially hazardous and should be done only at centres with substantial relevant experience in CHD.
- MRI or CT scan to define the anatomy and detect ductal aneurysm or calcification. MRI can also be used to estimate Qp/Qs.
Part IV - Indications for Intervention
The following situations warrant intervention:
|
||
Part V - Surgical/Interventional Technical Options
|
Device closure is the preferred method for the small ductus and when possible, should be planned at the same time as the diagnostic catheterization.
The presence of ductal calcification increases surgical risk and favours device closure. |
||
| Surgical closure should be reserved for those in whom the PDA is too large for device closure. Examples in which the ductal anatomy may be so distorted as to not be acceptable for device closure might include aneurysm or post-endarteritis. Operative repair should probably be undertaken by congenital heart surgeons. | ||
Part VI - Surgical/Interventional Outcomes
Device closure.
Successful closure is achieved in the large majority of attempts using a variety of devices. (45,49,50) More than 85% of ducts are closed by one year following device placement. In a small proportion of patients, a second or even a third device may need to be placed. This is usually deferred for at least 6 months. Recanalization is rare but can occur.
Surgical closure.
More than 95% of ducts can be closed by surgery. Recanalization is unusual but recognized.
Postoperative complications may include recurrent laryngeal or phrenic nerve damage and thoracic duct damage.
Part VII - Pregnancy
Pregnancy is well tolerated in women with silent and small PDA or in patients with functional class 1 or 2 prior to pregnancy.
| Pregnancy is contraindicated in Eisenmenger syndrome because of the high maternal (up to 50%) and fetal (up to 60%) mortality. | ||
Part VIII - Follow Up
|
Patients who have been repaired should have periodic evaluation by an ACHD cardiologist because recanalization can occur or residual problems (pulmonary hypertension, left ventricular dysfunction, atrial fibrillation) may persist or develop. Patients with devices in situ should be followed periodically because the natural history of these devices is unknown.
Endocarditis prophylaxis is recommended for 6 months following PDA device closure or for life if any residual defect persists. Patients with a silent PDA do not require follow up or endocarditis prophylaxis. |
||
APPENDIX I
Types of Patients who may be cared for Exclusively in the Community
Valves:
- Isolated aortic valve disease
- Isolated mitral valve disease (except parachute mitral valve and similar anomalies)
- Mild pulmonic valve stenosis
- Isolated tricuspid valve disease (except Ebstein anomaly)
- Secundum atrial septal defect (closed, no residual shunt, no arrhythmia, no pulmonary hypertension))
- Ductus arteriosus after complete closure with no residua
- Ventricular septal defect (small and isolated, or repaired with no residual lesions)
- Repaired partial anomalous pulmonary venous connection
APPENDIX II
Types of Patients who Should be Seen at National or Regional ACHD Centres (Alphabetical)
- Aorto-left ventricular fistula
- Atrioventricular septal defects
- Coarctation of the aorta
- Complete transposition of the great arteries
- Congenitally corrected transposition of the great arteries
- Coronary artery anomalies (except incidental findings)
- Criss-cross heart
- Cyanotic congenital heart patients (All)
- Double outlet ventricle
- Ebstein anomaly
- Eisenmenger syndrome
- Fontan procedure
- Heterotaxy syndromes
- Infundibular right ventricular outflow obstruction of significance
- Mitral atresia
- One ventricle (also called double inlet, double outlet, common, single, primitive)
- Partial anomalous pulmonary venous connection
- Patent ductus arteriosus (not closed)
- Pulmonary atresia (all forms)
- Pulmonary hypertension complicating CHD
- Pulmonic valve regurgitation (moderate or greater)
- Pulmonic valve stenosis (moderate to severe)
- Pulmonary vascular obstructive disease
- Sinus of Valsalva fistula/aneurysm
- Subvalvar or supravalvar aortic stenosis
- Tetralogy of Fallot
- Total anomalous pulmonary venous connection
- Tricuspid atresia
- Truncus arteriosus or Hemi-truncus
- Valved conduits
- Ventricular septal defect with:
- Absent valves
- Aortic regurgitation
- Aortic coarctation
- Mitral disease
- Right ventricular outflow tract obstruction
- Straddling tricuspid and/or mitral valve
- Subaortic stenosis
APPENDIX III
| Level of Evidence | Grade of Recommendation |
| Level I: Large randomized trials with clear-cut results, and low risk of error | A |
| Level II: Randomized trials with uncertain results and/or moderate to high risk of error | B |
| Level III: Nonrandomized studies with contemporaneous controls | C |
| Level IV: Nonrandomized studies with historical controls | C |
| Level V: Case series without controls | C |
APPENDIX IV
| UNIVERSITY/CENTRE | LOCATION | CONTACT PERSON |
| Memorial University | St. John's, NF | Dr. Anne Williams |
| Dalhousie University | Halifax, NS | Dr. Catherine Kells |
| Laval University | Ste-Foy, PQ | Dr. Marie-Helene Leblanc |
| McGill University | Montreal, PQ | Dr. Francois Marcotte |
| University of Montreal | Montreal, PQ | Dr. Annie Dore |
| Queen's University | Kingston, ON | Dr. Gary Burggraf |
| University of Ottawa | Ottawa, ON | Dr. Kwan Chan |
| University of Toronto | Toronto, ON | Dr. Gary Webb |
| McMaster University | Hamilton, ON | Dr. Elaine Gordon |
| University of Western Ontario | London, ON | Dr. Lynn Bergin |
| University of Manitoba | Winnipeg, MB | Dr. James Tam |
| University of Saskatchewan | Saskatoon, SK | Dr. James McMeekin |
| University of Calgary | Calgary, AB | Dr. Nanette Alvarez |
| University of Alberta | Edmonton, AB | Dr. Dylan Taylor |
| University of British Columbia | Vancouver, BC | Dr. Marla Kiess |
APPENDIX V
ABBREVIATIONS USED IN THE TEXT
| ACHD | adult congenital heart disease |
| ASD | atrial septal defect |
| AV | atrioventricular |
| AVSD | atrioventricular septal defect |
| CACH | Canadian Adult Congenital Heart [Network] |
| CBC | complete blood count |
| Cath | Catheterization |
| CCS | Canadian Cardiovascular Society |
| CHD | congenital heart disease |
| CT | computed tomography |
| ECG | Electrocardiogram |
| EPS | electrophysiologic study |
| ICU | intensive care unit |
| LV | left ventricle |
| LVOTO | left ventricular outflow tract obstruction |
| MRI | magnetic resonance imaging |
| NYHA | New York Heart Association |
| PA | pulmonary artery |
| PAP | pulmonary artery pressure |
| PDA | patent ductus arteriosus |
| PFO | patent foramen ovale |
| PHT | Pulmonary hypertension |
| PLE | protein-losing enteropathy |
| PS | pulmonary stenosis |
| Qp | pulmonary blood flow |
| Qs | systemic blood flow |
| RV | right ventricle |
| RVOT | right ventricular outflow tract |
| RVOTO | right ventricular outflow tract obstruction |
| SABP | systemic arterial blood pressure |
| SVC | superior vena cava |
| TEE | transesophageal echocardiogram |
| TIA | transient ischemic attack |
| TTE | transthoracic echocardiogram |
| TV | tricuspid valve |
| VSD | ventricular septal defect |
APPENDIX VI
SHUNTS (Palliative surgical interventions to increase pulmonary blood flow)
Systemic Venous-to-Pulmonary Artery Shunts
| Classic Glenn | SVC to right PA |
| Bi-directional Glenn | SVC to right and left PA |
| Bilateral Glenn | Right and left SVC to right and left PA respectively |
Systemic Arterial-to-Pulmonary Artery Shunts
| Classic Blalock-Taussig | Subclavian artery to ipsilateral PA (end-to-side) |
| Modified Blalock-Taussig | Subclavian artery to ipsilateral PA (prosthetic graft) |
| Potts' Anastomosis | Descending aorta to left PA |
| Waterston Shunt | Ascending aorta to right PA |
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