Tetralogy of Fallot is the most prevalent severe congenital heart disease. Although surgery has led to improved life expectancy, residual pulmonary regurgitation is common. Patients with pulmonary regurgitation go on to develop exercise intolerance, heart failure, arrhythmias and sudden cardiac death. Pulmonary valve replacement is increasingly used to prevent right ventricular failure. Our limited understanding of remodeling of the right heart hampers our ability to detect subtle right ventricular dysfunction in the early stages and prevent irreversible heart failure. Echocardiographic metrics have poor sensitivity in assessing the very early stages of right ventricular failure. Currently we select patients for pulmonary valve intervention based on a right ventricular volume threshold measured on MRI. This paradigm places too much emphasis on volume and too little on ventricular function. The lack of precise imaging markers of early right heart failure in Tetralogy of Fallot is one of the largest gaps in knowledge facing congenital cardiologists. Being able to detect early right heart failure before progression to irreversible heart failure would allow cardiologists to follow these at-risk patients more closely and offer pulmonary valve replacements sooner rather than later. In addition, being able to use imaging to identify subtle stages of early right heart failure can help pharmaceutical companies and other physician-scientists test therapeutic response. I hypothesize that innovative imaging markers derived from computational assessments of cardiac MRI and echocardiographic imaging during peak exercise will outperform traditional markers in predicting early right ventricular failure in Tetralogy of Fallot patients. The goal of this study is to compare the relationship between cardiac flow and right ventricular function in Tetralogy of Fallot patients, and then predict heart failure using changes in ventricular shape, strain, and contraction at peak exercise. By completing this project, I will uncover key insights into the relationship among cardiac flow, morphologic changes of the right ventricle and right ventricular function which will bridge a major knowledge gap regarding imaging markers for the detection of early and subtle right heart failure in the Tetralogy of Fallot population. Being able to identify early right heart failure will change how cardiologists treat Tetralogy of Fallot patients clinically. My long-term goal as a physician-scientist is to become an academic cardiologist, future junior faculty member and expert in right heart failure in adults with congenital heart disease.
Current imaging assessments of right ventricular function in Tetralogy of Fallot patients remain challenging and imprecise. Being able to detect early and subtle right heart failure before progression to irreversible heart failure would allow cardiologists to follow at-risk Tetralogy of Fallot patients more closely and offer pulmonary valve replacements sooner rather than later. This project aims to compare the relationship between cardiac flow and right ventricular function in Tetralogy of Fallot patients, and then predict heart failure using changes in ventricular shape, strain, and contraction at peak exercise, thus bridging a major knowledge gap regarding imaging markers for the detection of early and subtle right heart failure in the Tetralogy of Fallot population.
