Predictors of Electrical Storm in Patients With Idiopathic Dilated Cardiomyopathy - How to Stratify the Risk of Electrical Storm

Background: Electrical storm (ES) is a serious problem in patients with an implantable cardioverter defibrillator (ICD). However, insufficient reports have indicated the predictors of ES in ICD patients with idiopathic dilated cardiomyopathy (DCM) The purpose of this study was to clarify the predictors of ES for risk stratification in DCM patients with an ICD Methods and Results: Of 446 ICD patients, 53 DCM patients were included in this study During a mean follow-up of 55 +/- 36 months. ES (>= 3 times appropriate ICD therapy within 24h) occurred in 18/53 (34%) patients According to multivariate Cox proportional hazard regression analysis, a duratidn of the terminal low amplitude signals of <40 mu V (LAS40) (HR 1 4/10 ms increase, 95% confidence interval (CI) 1 1-2 1, P=0 0049) or root mean square voltage of the last 40 ms of the QRS complex (RMS40) (HR 088/1 mu V, 95%CI 0 77-0 96, P=0 001) on the signal averaged electrocardiogram, and a history of atrial fibrillation (AF) before ICD implantation (HR 2 3, 95%CI 1 2-5.0, P=0 013) were independently associated with an increased risk of ES Conclusions: Our data indicated that a longer LAS40, lower RMS40 and history of AF before ICD implantation could strongly predict ES. and the combination of those parameters could effectively stratify the risk of ES in DCM patients (Circ J 2010, 74: 1822-1829)