**7. Summary and conclusions**

Since the initial description of the Fontan operation in the early 1970s by Fontan, Kruetzer, and their associates, several modifications have been introduced. These include avoiding classic Glenn anastomosis; not using a prosthetic valve in the IVC; RA-PA anastomosis, direct or through a non-valved conduit; RA-PA anastomosis through a valved conduit; RA-RV anastomosis, direct or non-valved anastomosis; RA-RV anastomosis through a valved conduit; bidirectional Glenn procedure (cavopulmonary anastomosis); lateral tunnel; total cavopulmonary connection; extra-cardiac conduit, staged Fontan; fenestrated Fontan; and closure of Fontan fenestration. Currently staged, total cavopulmonary connection with extra-cardiac conduit and fenestration has become the most commonly used multistage surgery in accomplishing the Fontan.

The indications for Fontan are patients who have one functioning ventricle, and these include tricuspid atresia, double-inlet left ventricle, HLHS, mitral atresia with normal aortic root, unbalanced AVSDs, pulmonary atresia with intact ventricular

**147**

**Author details**

Stage IIIA.

**Conflict of interest**

P. Syamasundar Rao

Hermann Hospital, Houston, TX, USA

provided the original work is properly cited.

University of Texas at Houston, McGovern Medical School and Children's Memorial

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

septum with markedly hypoplastic right ventricle, and other complex heart defects with one functioning ventricle. Recently there has been a trend for biventricular

Both the immediate and follow-up results have remarkably improved, both in terms of mortality and morbidity, following the introduction of staged total cavopulmonary connection with extra-cardiac conduit and fenestration with subsequent catheter closure of Fontan fenestration. Complications do occur during follow-up,

Stage I consists of performing palliative procedures on the basis of pathophysiology of the defect complex at presentation, usually in the neonatal period. Stage II involves performing a bidirectional Glenn procedure (diversion of the superior vena caval blood flow into both lungs) usually at about the age of 6 months. During stage IIIA diversion of the IVC blood flow into the lungs, usually by an extra-cardiac conduit plus a fenestration, usually at about the age of 2 years. Stage IIIB consists of transcatheter closure of the fenestration 6–12 months after

\*Address all correspondence to: p.syamasundar.rao@uth.tmc.edu

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

repair, particularly for patients with unbalanced AVSDs.

and they should be addressed as and when they are detected.

The author declares no conflict of interest.

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

*Advances in Complex Valvular Disease*

the wide use of staged TCPC.

**Figure 16.**

in accomplishing the Fontan.

**7. Summary and conclusions**

Following a short trial of any of the above treatment modes, largely on the basis of the cardiologist's preference, a more definitive treatment methods such as lessening the conduit pressure by creating a fenestration between the conduit and the atrium [99–101], converting atriopulmonary type of Fontan to TCPC [87, 102, 103], instituting sequential atrioventricular pacing [104, 105], and performing cardiac transplantation [106–108] should all be considered. Again, it is essential to emphasize that timely treatment should be instituted as soon as PLE is identified [85]. Fortunately, the need for use of these methods has progressively diminished since

*(A) Selected cine frame from a right subclavian artery (RSA) cineangiogram showing branches (white arrows) of the thyrocervical (TC) trunk which supplied a number of small vessels, giving a good degree of levophase. (B) Complete occlusion occurred following the implantation of a Gianturco coil (C) (Reproduced from [95]).*

Since the initial description of the Fontan operation in the early 1970s by Fontan, Kruetzer, and their associates, several modifications have been introduced. These include avoiding classic Glenn anastomosis; not using a prosthetic valve in the IVC; RA-PA anastomosis, direct or through a non-valved conduit; RA-PA anastomosis through a valved conduit; RA-RV anastomosis, direct or non-valved anastomosis; RA-RV anastomosis through a valved conduit; bidirectional Glenn procedure (cavopulmonary anastomosis); lateral tunnel; total cavopulmonary connection; extra-cardiac conduit, staged Fontan; fenestrated Fontan; and closure of Fontan fenestration. Currently staged, total cavopulmonary connection with extra-cardiac conduit and fenestration has become the most commonly used multistage surgery

The indications for Fontan are patients who have one functioning ventricle, and these include tricuspid atresia, double-inlet left ventricle, HLHS, mitral atresia with normal aortic root, unbalanced AVSDs, pulmonary atresia with intact ventricular

**146**

septum with markedly hypoplastic right ventricle, and other complex heart defects with one functioning ventricle. Recently there has been a trend for biventricular repair, particularly for patients with unbalanced AVSDs.

Stage I consists of performing palliative procedures on the basis of pathophysiology of the defect complex at presentation, usually in the neonatal period. Stage II involves performing a bidirectional Glenn procedure (diversion of the superior vena caval blood flow into both lungs) usually at about the age of 6 months. During stage IIIA diversion of the IVC blood flow into the lungs, usually by an extra-cardiac conduit plus a fenestration, usually at about the age of 2 years. Stage IIIB consists of transcatheter closure of the fenestration 6–12 months after Stage IIIA.

Both the immediate and follow-up results have remarkably improved, both in terms of mortality and morbidity, following the introduction of staged total cavopulmonary connection with extra-cardiac conduit and fenestration with subsequent catheter closure of Fontan fenestration. Complications do occur during follow-up, and they should be addressed as and when they are detected.
