The Destination Therapy Evaluation for Failing Fontan Study

Purpose: The purpose of the Destination Therapy Evaluation for Failing Fontan Study (DEFINe Study) is to perform a single center physician-investigator led feasibility study to initiate examination of the safety and efficacy of implanting continuous flow circulatory support devices in 20 patients with failing Fontan physiology, not amenable to other surgical or medical therapy and who are not candidates for heart transplantation. Based upon the results of the DEFINe study, consideration would be given to a larger multicenter study. The primary endpoint is survival without a disabling stroke at two years. Safety, functional status, total days alive following hospital discharge and quality of life assessments will be evaluated as secondary endpoints. Background: Patients born with the congenital anomaly of a single ventricle often undergo Fontan procedures to improve oxygenation and circulation. As the patient matures, the benefits of the Fontan procedures become exhausted. These patients present as young adults with heart failure, and should be considered for heart transplantation. "Failed Fontan" physiology patients are now more commonly surviving into their 30s and 40s due to the advancement in surgical Fontan procedures over the last several decades. Yet, many patients are not appropriate transplant candidates due to progression of pulmonary failure that surpasses the pulmonary vascular resistance limits, end organ failure effects to the liver, and cardiac failure that does not present with left ventricular ejection fractions of less than 25%. Congenital heart disease is considered a higher risk indication for transplantation. Such patients present a complex anatomy, scar tissue from prior procedures, unique pathological states and limited ability to assess hemodynamics. Methods: Patients with failing Fontan physiology will be evaluated for surgical intervention, heart transplantation or participation in the study for long-term support, known as Destination Therapy (DT). Patients who do not meet the study criteria will be asked to participate in a sub-study to collect patient information. Consenting patients who meet the study criteria will be implanted with a HeartMate II Ventricular Assist Device (VAD) to improve cardiac output. Following VAD implantation, the patient will recover in the hospital, and then discharge to home or an approved facility. Study data will be collected as long as the patient receives VAD support. Placement of the VAD and continuing patient care should improve cardiac output and quality of life for this population of patients born with the congenital anomaly of a single ventricle. Outcomes: The primary endpoint of the study is to examine survival without a disabling stroke at two years (defined as a score of four or greater on the Modified Rankin Scale). Safety, functional status, total-days-alive following hospital discharge, and quality of life assessments will be evaluated as secondary endpoints.