Follow-up of the Single Ventricle Reconstruction ( SVR ) Trial

Doctor's Name: 
Lynn A. Sleeper, ScD
Hospital/Institution: 
New England Research Institutes / Pediatric Heart Network

Hypoplastic left heart syndrome ( HLHS ) is a congenital heart defect that occurs when the left sided structures of the heart are very underdeveloped and the right ventricle is the only usable ventricle ( single ventricle ). Newborn infants with HLHS must have surgery to make sure that blood can flow to both the body and the lungs. This surgery is called the “Norwood procedure”. The Norwood procedure includes sending blood to the lungs through a small tube that connects the blood vessel going to the body to the blood vessel going to the lung ( pulmonary artery ), this is known as a modified Blalock-Taussing shunt ( BT shunt ). Recently, some surgeons have connected the right ventricle to the pulmonary artery using a small tube, known as an RV-to-PA shunt, instead of using the BT shunt. There are some theoretical advantages to RV-to-PA shunt, but there have been no studies directly comparing the results of these two shunt types in the Norwood procedure.

The Pediatric Heart Network ( PHN ) is a multi-center clinical research network funded by the National Heart Lung and Blood Institute of the National Institutes of Health whose primary goal is to promote the evaluation of novel treatments and management strategies for children and young adults with congenital acquired heart disease. In May 2005, the PHN began enrolling patients in a randomized, multi-center clinical study, the “Trial of RV-to-PA vs. modified BT shunt in infants with single ventricle defect undergoing staged reconstruction ( SVR Trial )”. This study is primarily comparing death or transplant between the BT shunt group and the RV-to-PA shunt group in the first year of life. Other comparisons will be made between the groups and include complications, the need for other surgeries, the function of the heart, and the growth and development of the children. A total of 466 patients will be enrolled by Fall of 2007 and data collection for this study will be completed the end of 2008.

The original study included plans to follow the patients only until they reached 14 months of age. The patients enrolled in this study represent a unique, multi-institutional, prospectively enrolled cohort, which is the most well-characterized group of patients to date who will have undergone the Norwood procedure. No large prospective, multi-institutional studies of the natural history of surgically treated HLHS patients of this magnitude have been performed. The PHN investigators have developed a follow-up study protocol to continue to allow ongoing evaluation and comparison of the condition of these children as they undergo their second required surgery and as they grow older. The Children’s Heart Foundation is providing bridge funding to support start-up of the SVR Follow-up Study and is playing a critical role in ensuring that the follow-up study can begin without delay.

Award Date 1: 
2007
Award Amount 1: 
$50,000