2397Lesion-specific risk for sudden cardiac death or life-threatening ventricular arrhythmias in adult congenital heart disease

Abstract

Abstract Background Risk models for primary prevention strategies in adult congenital heart disease (ACHD) must incorporate the heterogeneous risk for sudden cardiac death (SCD) and life-threatening ventricular arrhythmias (LTVA) as stratified by underlying lesion. Objectives To determine lesion-specific risk for SCD and LTVA in ACHD. Methods We analyzed 3311 ACHD patients (50% males) prospectively followed-up for 37510 person/years. SCD cases were confirmed by means of the Spanish National Death Registry. In addition, we identified all cases of resuscitated cardiac arrest or ventricular tachycardia requiring cardioversion. According to the incidence rate of the composite end-point of SCD and LTVA, lesions were stratified into four groups of risk. Cumulative freedom from SCD or LTVA in patients at high, moderate, low and very low risk were compared by using Cox regression model with left truncation. The c-index of this lesion-specific risk stratification was calculated by using the β-coefficients. The discriminative ability of this lesion-specific risk stratification was also tested in an external cohort of 203 SCD-LTVA cases and 2287 controls from 20 different centers. Results 71 patients experienced an event (53 SCD, 18 LTVA). Patients at highest risk (incidence rate >1%) were those with Rastelli procedure, severe coronary abnormalities, complex Fallot and cyanotic patients, either Eisenmenger or non-Eisenmenger; at moderate risk (incidence rate 0.25–1.0%) non-complex Fallot, Mustard/Senning repair, Fontan procedures and congenitally corrected transposition; at low risk (incidence rate 0.1–0.25%) Ebstein anomaly and left heart lesions; and at very low risk (incidence rate <0.1%) left-to-right shunts and right ventricular outflow lesions. The discriminative ability in a multicenter external cohort was excellent (c-index ranged from 0.748 to 0.819 by center). Lesion-specific risk and C-index Conclusions A lesion-specific risk stratification based on the incidence rate of SCD and LTVA was performed and validated. This approach could result in a more individualized risk assessment. Acknowledgement/Funding Instituto de Salud Carlos III, Ministerio de Economía y Competividad, Spain (Exp PI14/02099 and PI17/01327) and co-financed by FEDER