Outcome Prediction After Tetralogy of Fallot Repair: A Prospective Clinical and Cardiovascular Magnetic Resonance Study

Abstract

BACKGROUND: Identification of individuals at risk for major adverse cardiovascular events is essential for contemporary management of patients with repaired tetralogy of Fallot. We sought to identify clinical and cardiovascular magnetic resonance imaging (CMR) predictors of adverse clinical outcomes in repaired tetralogy of Fallot. METHODS: Children and adults prospectively enrolled in the CORRELATE (Comprehensive Outcomes Registry Late After Tetralogy of Fallot Repair) registry followed in North American, European, and Asian centers were studied. All patients had at least moderate pulmonary regurgitation and CMR at enrollment. Time-to-event analyses were performed from CMR completion to primary outcome, defined as mortality, resuscitated sudden death, sustained ventricular arrhythmia, or heart failure admission. Principal component analysis was used to create distinct CMR scores that collectively captured 80% of the variance among 10 CMR measures (systolic function, biventricular volumes/mass, and biatrial areas). RESULTS: In 720 patients (55% male, median age 30.3±14 years, 78% adult) with mean follow-up 5.7±1.8 years, the primary outcome occurred in 38 patients (5.2%) at a rate of 0.9/100 patient-years. A well-calibrated risk scoring system was created for prediction of the primary outcome at 5 years based on 5 predictors: age, diabetes, right ventricular systolic pressure, and 2 CMR principal component scores (predominantly reflecting atrial areas in the first principal component score and ventricular volumes in the second principal component score) (c-statistic for the composite risk score 0.79 [95% Cl, 0.71-0.88]). CONCLUSIONS: Clinical and imaging characteristics can contribute to risk prediction in repaired tetralogy of Fallot. Further study will be required to evaluate the utility of a risk scoring system for identification of individuals who may benefit from enhanced surveillance, intensified medical therapy, and/or optimally timed intervention.