fenestration		An opening, or "window" (usually small) between two structures, which may be spontaneous, traumatic, or created surgically.
fibrillin		Fibrillin is a large glycoprotein, closely involved with collagen in the structure of connective tissue. Mutations in the fibrillin gene on chromosome 15 are responsible for all manifestations of Marfan syndrome. see also Marfan syndrome.
Fontan procedure (operation)		A palliative operation for patients with a univentricular circulation, involving diversion of the systemic venous return to the pulmonary artery usually without the interposition of a sub-pulmonary ventricle. There are many variations, all leading to normalization of systemic oxygen saturation and elimination of volume overload of the functioning ventricle.
classic Fontan		Originally, a valved conduit between the right atrium and the pulmonary artery (Fontan F, Baudet E. Surgical repair of tricuspid atresia. Thorax 1971;26:240-248.) Subsequently changed to a direct anastomosis between RA and PA.
extracardiac Fontan		IVC blood is directed to the pulmonary artery via an extracardiac conduit. The SVC is anastomosed to the PA as in the bi-directional Glenn shunt.
fenestrated Fontan		Surgical creation of an ASD in the atrial patch or baffle to provide an escape valve, allowing right to left shunting to reduce pressure in the systemic venous circuit, at the expense of systemic hypoxemia.
lateral tunnel		total cavo-pulmonary connection (TCPC).
RA-RV Fontan		Conduit (often valved) between RA and RV. Also known as the Björk modification. (Björk VO et al. Right atrial-ventricular anastomosis for correction of tricuspid atresia. J Thorac Cardiovasc Surg 1979;77:452-458.)
total cavo-pulmonary connection (TCPC)		IVC flow is directed by a baffle within the right atrium into the lower portion of the divided SVC or the right atrial appendage, which is connected to the pulmonary artery. The upper part of the SVC is connected to the superior aspect of the pulmonary artery as in the bi-directional Glenn procedure. The majority of the right atrium is excluded from the systemic venous circuit. syn. lateral tunnel Fontan