Purpose:to study the frequency and causes of appropriate ICD/CRT-D shocks in patients with dilated cardiomyopathy (DCM) depending on its etiology.
Methods: in 32 patients (11 females, 47.3±12.3 years) with non-ischemic DCM syndrome (the average left ventricle diastolic diameter was 6.8±0.8 cm, EF 24.7±9.5%) were ICD (n = 19) or CRT-D (n = 13) implanted. In 29 patients device was implanted for primary prevention.
Results: uring a mean follow-up of 18.5 [6.0, 31.5] months, an appropriate shocks developed in 8/32 (25.0 %) patients, including 7/29 (24.1%) patients who had defibrillators implanted for primary prevention. Fife of these patients had association of myocarditis with left ventricular noncompaction, two patients had primary (idiopathic) DCM and own patient had Emery-Dreifuss muscular dystrophy. Patients with isolated myocarditis (inflammatory cardiomyopathy) had no appropriate shocks. Causes of shocks were amiodarone discontinuance (n = 2, in own case with replacement for digoxin), development of acute myocarditis in patients with noncompact myocardium (n = 2), amiodarone induced thyrotoxicosis (n = 1), emergency abdominal surgery (n = 1). In two cases ventricular tachycardia and fibrillation developed due to terminal cardiac failure. Patients without shocks had significantly lower EF than patients with shocks (22.6±7.9% vs 32.4±11.4%, p<0.05). Mortality during follow-up was 25.0% (n = 8), including 5 patients without appropriate shocks.
Conclusions: In patients with different forms of DCM syndrome ICD implantation is reasonable and effective for primary prevention of sudden. The etiology of DCM syndrome is a more important predictor of shocks than the left ventricular EF.