Factors associated with mortality or transplantation versus Fontan completion after cavopulmonary shunt for patients with tricuspid atresia

Factors associated with mortality or transplantation versus Fontan completion after cavopulmonary shunt for patients with tricuspid atresia

Connor P. Callahan, MD,a Anusha Jegatheeswaran, MD, PhD,a David J. Barron, MD,a S. Adil Husain, MD,b Pirooz Eghtesady, MD, PhD,c Karl F. Welke, MD, MS,d Christopher A. Caldarone, MD,e David M. Overman, MD,f James K. Kirklin, MD,g Marshall L. Jacobs, MD,h Linda M. Lambert, MSN-cFNP,b William M. DeCampli, MD, PhD,i and Brian W. McCrindle, MD, MPH,j the Congenital Heart Surgeons’ Society Tricuspid Atresia Working Group. J Thorac Cardiovasc Surg. 2021 Apr 30;S0022-5223(21)00745-5. PMID: 34045062.

Take Home Points:

  • Failure to achieve Fontan completion in patients with tricuspid atresia is higher than expected (5%).
  • Even cavo-pulmonary shunt (CPS) reduces the ventricular volume, mitral valve repair should be considered at the time of CPS, if moderate or greater.

Commentary from Dr. Yasuhiro Kotani (Okayama, Japan), section editor of Congenital Heart Surgery Journal Watch: 

Summary: A total of 417 patients younger than 3 months of age with tricuspid atresia were retrieved from 40 centers in the Congenital Heart Surgeon’s Society. Cavo-pulmonary shunt (CPS) was performed in 382 patients and 5% died or underwent heart transplantation (no Fontan operation). Prenatal diagnosis and pulmonary artery banding (PAB) at the time of CPS were negatively associated with Fontan completion. Preoperative moderate or greater mitral valve regurgitation (MR), concomitant mitral valve repair, PAB at CPS, postoperative superior vena cava interventions, and CPS takedown were associated with death/transplantation.

Significance: This study identified a relatively higher rate of failed Fontan achievement in tricuspid atresia with normal great arteries which appeared to be favorable anatomy for Fontan completion. Risk factors for death/transplant included PAB at CPS, MR, and CPS takedown. This study makes us reconsider the patient selection and surgical indication for CPS.

Comment: As we all know, TA without transposition of the great arteries is the most favorable condition of single ventricle and usually promises a “good” Fontan pathway. This study indeed showed 17 patients died and 1 patient needed transplantation (among a cohort of 417 patients) which was considered to be higher than expected. They showed PAB at the time of CPS was associated with worse outcome. Although there was no significant difference in mean PA pressure or trans-pulmonary gradient between patients with PAB and those without, patients with PAB had a high rate of branch pulmonary stenosis (38%) and this may affect the pulmonary condition. The impact of antegrade pulmonary flow by PAB at CPS is still in debate. Previous CHSS studies showed pros and cons with regard to leave the antegrade flow at CPS and no answer was made. There may be a patient selection bias and we do not know how this affected on worse clinical outcome. Mitral regurgitation (MR) is also identified as a risk for death/heart transplantation. This is consistent finding from previous literatures even CPS can decrease systemic ventricular volume and contributes to maintain ventricular function. This study recommended to intervene moderate or more MR to recruit the borderline Fontan candidates. This study demonstrated that 54 patients were alive without Fontan completion and this number is not negligible. Of these 10 patients were 3 years or more from CPS. Their echocardiogram showed good LV function except 1 patient and no data were available why these 10 patients did not undergo Fontan completion. Because of the nature of the multi-center retrospective study, the study did not find the reason why these patients did not go for Fontan completion. Further study to profile these patients is necessary to improve the achievement of Fontan completion.