Pediatric/Adult Congenital Heart Disease -> Adult Congenital Heart Disease D-PO02 - Poster Session II (ID 47) Poster

D-PO02-073 - Risk Of Ventricular Arrhythmias Following Transcatheter Pulmonary Valve Replacement In Adults With Repaired Tetralogy Of Fallot: How Do We Risk Stratify? (ID 1002)


Background: Ventricular arrhythmias (VA) are a major cause of morbidity and mortality in adults with repaired Tetralogy of Fallot (TOF) and to date, all studies evaluating prevalence and risk for VA have focused on those undergoing surgical pulmonary valve replacement. Transcatheter pulmonary valve replacement (TPVR) has become a significant option for many patients (pts) with repaired TOF.
Objective: We sought to determine prevalence and risk factors for VA in those undergoing TPVR with repaired TOF.
Methods: A retrospective 10 yr single center study was performed on pts with repaired TOF >18 years, who underwent TPVR. Medical records were reviewed to assess VA events, defined as sudden cardiac arrest, wide complex tachycardia, and appropriate implantable cardioverter-defibrillator (ICD) therapies. Demographic, hemodynamic and surgical factors were assessed and compared using Fisher’s exact tests and Mann-Whitney U tests.
Results: A total of 81 pts were included, mean age at TPVR 27.3 + 13 yrs and mean follow up 6.4 + 3.1 years. Pts were categorized by published risk factors for VA in TOF: 33 (41%) low risk, 42 (52%) moderate risk, and 6 (7%) high risk. Importantly, 19 pts (23%) were reclassified from low to moderate risk based on left ventricular end diastolic pressure (LVEDP) >12mmHg at TPVR, including the only death from VA. Overall, 4 pts had significant VA events, all moderate risk category: 1 death due to ventricular fibrillation, 2 with appropriate ICD discharges and 1 with ventricular anti-tachycardia pacing. There was no significant difference in QRS duration, LVEDP, ventricular function, or ventricular end diastolic dimensions between the VA group and the non-VA group.
Conclusion: In the first study to report VA in adults with TOF undergoing TPVR, the prevalence of VA events is similar to that previously reported for those undergoing surgical PVR. All VA post -TPVR occurred in moderate risk pts and nearly a quarter of the pts were reclassified from low to moderate risk based upon hemodynamics at TPVR. There is currently no standard approach for this patient population regarding electrophysiology testing. The results from our study warrant further investigation as to whether pts following TPVR and moderate risk should undergo further testing and risk assessment.