*4.1.1 Decreased pulmonary blood flow*

In neonates with decreased pulmonary blood flow, the ductus arteriosus should be kept open by administration of prostaglandin E1 (PGE1) intravenously at a dose of 0.05–0.1 mcg/kg/min. Once the O2 saturation improves, the dosage of PGE1 is gradually reduced to 0.02–0.025 mcg/kg/min to minimize the side effects of the prostaglandins. Following stabilization and diagnostic studies, as necessary to confirm the diagnosis, a more permanent way of providing pulmonary blood flow should be instituted. A number of methods to augment pulmonary blood flow have been used over the years [49, 50]. These include subclavian artery to ipsilateral PA anastomosis (classic Blalock-Taussig shunt), descending aorta to the left PA anastomosis (Potts shunt), ascending aorta to the right PA anastomosis (Waterston-Cooley shunt), SVC to right PA anastomosis, end-to-end (classic Glenn shunt), enlargement of the ventricular septal defect (VSD), formalin infiltration of the wall of the ductus arteriosus, central aortopulmonary fenestration or expanded polytetrafluoroethylene (Gore-Tex; W. L. Gore and Associates, Inc., Newark, Delaware) shunt, Gore-Tex interposition graft between the subclavian artery and the ipsilateral PA (modified Blalock-Taussig shunt), balloon pulmonary valvuloplasty, and stent implantation into the ductus arteriosus. Currently modified Blalock-Taussig (BT) shunt [51] by insertion of a Gore-Tex graft between the subclavian artery to the ipsilateral PA (**Figure 1a**) is performed by most surgeons to address pulmonary oligemia. More recently connecting the RV outflow tract with the PA via non-valve Gore-Tex graft is being used at several institutions to palliate pulmonary oligemia. Placement of a stent in the ductus arteriosus [52–54] and balloon pulmonary valvuloplasty (if the predominant obstruction is at the pulmonary valve level) [55–57] are other available options to augment the pulmonary blood flow.

**133**

BT shunt.

*Fontan Operation: A Comprehensive Review DOI: http://dx.doi.org/10.5772/intechopen.92591*

*4.1.2 Increased pulmonary blood flow*

*4.1.3 Normal pulmonary blood flow*

*4.1.4 Hypoplastic left heart syndrome*

*4.1.5 Address other defects during Stage I*

control of CHF.

**Figure 1.**

*from [30]).*

In babies with increased pulmonary blood flow, optimal anti-congestive measures should be started immediately. Once the congestive heart failure (CHF) is adequately addressed, PA banding (**Figure 1b**) is performed [58] irrespective of

*Stage I Fontan. Selected frames form cineangiograms in two different babies; the first with pulmonary oligemia who received Blalock-Taussig (BT) shunt (a) and the second with pulmonary plethora who had pulmonary artery banding (PB) (b). C, catheter; LPA, left pulmonary artery; RPA, right pulmonary artery (Reproduced* 

Infants with near normal pulmonary blood flow with O2 saturations in the low

Neonates with hypoplastic left heart syndrome usually have Norwood palliation

80s do not need intervention and are clinically followed until Stage II.

(**Figure 2**) [37, 59] in the neonatal period; in this operation, the following procedures are performed: (1) the main pulmonary artery and the aorta are anastomosed together; additional prosthetic material is used as needed; (2) the pulmonary circulation receives blood supply by connecting the aorta to the PA via a modified BT shunt [51] (**Figure 2b**); (3) atrial septum is excised to allow unhindered blood flow from the left to the atrium; and (4) ductal tissue is removed, and coarctation of the aorta, if present is repaired. Some surgeons use alternative Sano shunt [60], connecting the RV outflow tract to the PA (**Figure 2c**) instead of

In patients with inter-atrial obstruction, it should be relieved either by transcatheter methodology or by surgery as deemed appropriate for a given clinical scenario. If there is associated coarctation of the aorta, it should also be relieved. Some patients with double-inlet left ventricle may have significant obstruction at the level of bulboventricular foramen [61]. Similarly some babies with tricuspid

### **Figure 1.**

*Advances in Complex Valvular Disease*

**4. Current status of Fontan operation**

**4.1 Stage I**

defect (CHD).

*4.1.1 Decreased pulmonary blood flow*

conduit and fenestration. It is performed in three stages.

donor hearts, most institutions have reverted to the Norwood/Fontan route. In addition, following successful cardiac transplantation, multiple medications for the prevention of graft rejection, frequent outpatient visits and periodic endomyocardial biopsy, to recognize rejection very early, are necessary in the management of these children. At the present time, cardiac transplantation is used

As reviewed above, since the original description in the early 1970s, the Fontan procedure has undergone numerous modifications, and, at the present time it is best described as staged total cavopulmonary connection (TCPC) with an extra-cardiac

The majority, if not all, of patients who require Fontan operation (see Section 3. Indications for Fontan Operation) present during the neonatal and early infancy period, and the Fontan cannot be performed at that time because of naturally high PA pressure and high pulmonary vascular resistance (PVR). Therefore, Fontan, by necessity, becomes a multistage procedure. These babies should receive palliative intervention to allow them to reach the age and size to undergo successful Fontan surgery. The type of palliation is largely dependent upon the hemodynamic disturbance produced by multiple defects associated with a given congenital heart

In neonates with decreased pulmonary blood flow, the ductus arteriosus should be kept open by administration of prostaglandin E1 (PGE1) intravenously at a dose of 0.05–0.1 mcg/kg/min. Once the O2 saturation improves, the dosage of PGE1 is gradually reduced to 0.02–0.025 mcg/kg/min to minimize the side effects of the prostaglandins. Following stabilization and diagnostic studies, as necessary to confirm the diagnosis, a more permanent way of providing pulmonary blood flow should be instituted. A number of methods to augment pulmonary blood flow have been used over the years [49, 50]. These include subclavian artery to ipsilateral PA anastomosis (classic Blalock-Taussig shunt), descending aorta to the left PA anastomosis (Potts shunt), ascending aorta to the right PA anastomosis (Waterston-Cooley shunt), SVC to right PA anastomosis, end-to-end (classic Glenn shunt), enlargement of the ventricular septal defect (VSD), formalin infiltration of the wall of the ductus arteriosus, central aortopulmonary fenestration or expanded polytetrafluoroethylene (Gore-Tex; W. L. Gore and Associates, Inc., Newark,

Delaware) shunt, Gore-Tex interposition graft between the subclavian artery and the ipsilateral PA (modified Blalock-Taussig shunt), balloon pulmonary valvuloplasty, and stent implantation into the ductus arteriosus. Currently modified Blalock-Taussig (BT) shunt [51] by insertion of a Gore-Tex graft between the subclavian artery to the ipsilateral PA (**Figure 1a**) is performed by most surgeons to address pulmonary oligemia. More recently connecting the RV outflow tract with the PA via non-valve Gore-Tex graft is being used at several institutions to palliate pulmonary

pulmonary valvuloplasty (if the predominant obstruction is at the pulmonary valve level) [55–57] are other available options to augment the pulmonary blood flow.

oligemia. Placement of a stent in the ductus arteriosus [52–54] and balloon

for patients failing Fontan operation at a limited number of institutions.

**132**

*Stage I Fontan. Selected frames form cineangiograms in two different babies; the first with pulmonary oligemia who received Blalock-Taussig (BT) shunt (a) and the second with pulmonary plethora who had pulmonary artery banding (PB) (b). C, catheter; LPA, left pulmonary artery; RPA, right pulmonary artery (Reproduced from [30]).*
