Sudden Death and Defibrillators in Transposition of the Great Arteries With Intra-atrial Baffles

Abstract

Background-Transposition of the great arteries with intra-atrial baffle repair is among the congenital heart defects at highest risk of sudden death. Little is known about mechanisms of sudden death and the role of implantable cardioverter defibrillators. Methods and Results-We conducted a multicenter cohort study in patients with transposition of the great arteries to determine actuarial rates of implantable cardioverter defibrillator shocks, identify risk factors, assess underlying arrhythmias, and characterize complications. Overall, 37 patients (age, 28.0Ϯ7.6 years; 89.2% male) were enrolled from 7 sites. Implantable cardioverter defibrillators were implanted for primary prevention in 23 (62.1%) patients and secondary prevention in 14 patients (37.8%). Annual rates of appropriate shocks were 0.5% and 6.0% in primary and secondary prevention, respectively (Pϭ0.0366). Independent predictors were a secondary prevention indication (hazard ratio, 18.0; Pϭ0.0341) and lack of ␤-blockers (hazard ratio, 16.7; Pϭ0.0301). In patients with appropriate shocks, intracardiac electrograms documented supraventricular tachycardia preceding or coexisting with ventricular tachycardia in 50%. No patient with inducible ventricular tachycardia received an appropriate shock in comparison with 37.5% of noninducible patients (Pϭ0.0429). Inappropriate shocks occurred in 6.6% per year, more so in patients of lesser weight (hazard ratio, 0.91 per kg; Pϭ0.0168). Additionally, 14 patients (37.8%) experienced complications: 5 (13.5%) acute, 1 (2.7%) late generator related, and 12 (32.4%) late lead related. Conclusion-In

Inappropriate ICD Shocks in Pediatric and Congenital Heart Disease Patients

“…Khairy et al reported data from tetralogy of Fallot and transposition of the great arteries patient populations, demonstrating detection rates in patients receiving an appropriate shock of 213 bpm and 222 bpm, respectively. 34,81 Additionally, in a population of ICD patients with Brugada syndrome, the mean detected tachycardia rate in appropriate shocks was 335 bpm, with the suggestion that a single VF zone at 222 bpm would reduce IS by 70%, although it could potentially lead to the missing of appropriate shocks in 1.7% of patients. 82 The frequency of use of ATP and its effectiveness in this population is not well known, although some authors have found the success rate to be low, and have advocated against its routine use.…”

The Use of Implantable Cardioverter-defibrillators in the Prevention of Sudden Cardiac Death: A Focus on Congenital Heart Disease and Inherited Arrhythmia Syndromes

“…16,25 Inducible VAs at EPS and high ventricularectopy burden on ambulatory cardiac monitoring have not been associated with SCD in patients with TGA in studies to date. 25,28 Additionally, risk factors for malignant arrhythmias in the L-TGA population have been poorly studied to date, although systemic right ventricular dysfunction is accepted as a predictor of adverse outcomes and SCD.…”

Microvolt T-wave alternans in adults with complex congenital heart diseases

“…We observed these 2 clinical features more often in patients with abnormal MTWA, though only pulmonary hypertension was confirmed to increase the probability of this phenomenon. Sub-pulmonary ventricle pressure overload along with cyanosis-related tissue hypoxia, as well as segmental dilation and tortuosity of the coronary arteries typical for increased blood viscosity lead to the myocardial fibrosis creating a substrate for ventricular arrhythmia [28,29].…”