Abstract 17356: Accumulation of Risk Factors Increases the Risk of Fatal Arrhythmic Events in Patients with Ischemic Heart Disease or Those with Dilated Cardiomyopathy -A Report from the CHART-2 Study-

Background: Although the secondary prevention of fatal arrhythmic events (FAEs) with implantable cardioverter defibrillator (ICD) is established, the primary prevention of FAEs with ICD for patients with structural heart disease has been controversial. Currently, ICD implantation has been recommended for patients with severe left ventricular (LV) dysfunction. In this study, we re-evaluated the current risk stratification in patients with heart failure (HF). Methods and Results: Among 10,219 patients with stage B/C/D HF patients registered in our CHART-2 Study, we enrolled 5,610 patients with either IHD or DCM in NYHA Class I to III who had never experienced FAEs. We prospectively examined the association between their risk factors and FAEs (sudden cardiac death, arrhythmic death, sustained ventricular tachycardia, ventricular fibrillation or appropriate ICD therapy). During the median follow-up of 3.2 years, 97 FAEs occurred. FAEs more frequently occurred in patients who met the Class I indication for primary prevention with ICD by the ACC/AHA Guidelines (NYHA II/III and LV ejection fraction (LVEF)≤35%) compared with those who did not (10.2 vs. 1.2%, P 200pg/ml, LV end-diastolic dimension (LVDD)>55mm, non-sustained ventricular tachycardia (NSVT) and eGFR 2 . When including the number of risk factors as a co-variable, a trend analysis showed a stepwise increase in the risk of FAEs as an increased number of risk markers; 0.3, 0.8, 1.4, 3.4, 9.4, and 16.0% from 0 to 4 and more than 5, respectively. When limited to the patients with NYHA II/III and LVEF≤35% (n=315), chronic atrial fibrillation (AF) was an independent risk factor of FAEs but not LVDD>55 mm, NSVT, BNP>200 pg/ml or eGFR 2 . In addition, FAEs rate was increased up to 33% when patients with chronic AF simultaneously had 3 or more of the following factors; BNP>200 pg/ml, LVDD>55 mm, NSVT and eGFR Conclusions: These results indicate that accumulation of risk factors increases the risk of FAEs in patients with either IHD or DCM, especially when chronic AF is present.