Abstract 13767: Cardiac MRI Predictors of Good Long-term Outcomes in Patients With Repaired TOF

Abstract

Introduction: Good outcomes in adults with repaired tetralogy of Fallot (rTOF) are not well explored. Identifying markers of a benign clinical course late after TOF repair can guide resource utilization in this growing population. Methods: Clinical and CMR data were analyzed from the International Multicenter TOF Registry (INDICATOR). The clinical outcome was a composite of death, aborted sudden death, sustained ventricular and atrial arrhythmia, non-sustained ventricular tachycardia, and New York Heart Association functional class>II. Multinomial regression explored predictors of the 3-category outcome-Good and intermediate outcomes; defined as freedom from clinical outcome at 50 and <50 years respectively; and bad outcome; defined as having an adverse event at <50 years. Results: The cohort had 1088 patients-good outcome, n=96; intermediate, n=747; bad, n=245 with median age at last CMR 44 (40, 47); 21 (15, 28); 31 (20, 39) years respectively. Median follow-up was 8 (5, 11) years after CMR in event-free patients. Right ventricular (RV) parameters associated with a good outcome were smaller RV end-systolic volume index, higher RV ejection fraction (EF), lower RV mass index, and lower RV mass/volume ratio. Left ventricular (LV) parameters associated with a good outcome were lower LV mass index and LV mass/volume ratio. Multivariable models showed RV EF (OR 1.56 per 10% increase, p=.009) and RV mass index (OR 1.51, per 10 g/m 2 decrease, p=.002) as independently associated with good outcome after adjusting for age at CMR. Important thresholds identified in older patients (age ≥37 years) were RVEF ≥42% and RV mass index <39 g/m 2 . Combined, this subgroup had a 56% likelihood of a good outcome. Conclusions: Adults with rTOF and CMR findings of adequate RV systolic function and no significant ventricular hypertrophy are likely to have a benign clinical course by age 50 years. Frequency of cardiac testing in such patients may be lower than in those not fulfilling these criteria.