Implantable cardioverter defibrillator therapy in grown-up patients with transposition of the great arteries-role of anti-tachycardia pacing

Abstract

Background: Grown-up patients with surgically corrected dextro-transposition of the great arteries (dTGA) as well as patients with congenitally corrected transposition of the great arteries (ccTGA) carry a high risk of ventricular arrhythmias. Data regarding implantable cardioverter defibrillator (ICD) therapy and efficacy of anti-tachycardia pacing in these patients is limited.

Methods: Clinical data from a contemporary cohort of ICD carriers with atrial switch-corrected dTGA and burdened right ventricle or with ccTGA were obtained retrospectively from hospital records and patients were followed for additional 25 months prospectively. Clinical characteristics and ICD episode data were analyzed.

Results: Fourteen ICD carriers (8 male) with dTGA or ccTGA were included in the analysis. Four patients received the ICD for primary prevention based on severely reduced systemic ventricular function. The remaining patients had an ICD indication for secondary prevention. Cumulative follow-up added up to 113.5 patient-years. One patient died suddenly due to massive pulmonary embolism. One patient received a ventricular assist device. There were no arrhythmic deaths during the prospective follow-up period. Nine patients (64%) experienced a total of 177 ventricular tachyarrhythmias. Anti-tachycardia pacing was highly effective with 80% success rate in termination of arrhythmias. Five patients (36%) suffered from a total of 28 inappropriate ICD shocks for supraventricular tachycardia.

Conclusions: In a contemporary cohort of ICD carriers with dTGA and ccTGA we observed a high proportion of appropriate ICD therapies for ventricular tachyarrhythmias. Over a period of up to 15 years almost two thirds of the patients received appropriate therapies. ATP was highly effective in our cohort and should therefore be programmed whenever possible.

Keywords: Implantable cardioverter-defibrillator (ICD); anti-tachycardia pacing; sudden cardiac arrest; transposition of the great arteries.

Figure 1

Example of a fast VT (230 ms) in a patient with dTGA after Mustard’s correction. IEGM channels show (from top to bottom) atrial IEGM, ventricular IEGM and marker channel. The second ATP attempt (center panel) terminates the arrhythmia. A beat-to-beat cycle length plot of the complete episode is shown in the bottom panel.