Early and frequent defibrillator discharge in patients with cardiac sarcoidosis compared with patients with idiopathic dilated cardiomyopathy

Background Little is known about the suitability of implantable cardioverter defibrillator (ICD) implantation in patients with cardiac sarcoidosis (CS). We evaluated the efficacy of ICD implantation in patients with CS, including suspected CS, compared with those with idiopathic dilated cardiomyopathy (DCM). Methods A total of 102 consecutive patients with definite CS, suspected CS, or DCM who underwent ICD implantation were enrolled. The endpoint was the first documentation of appropriate ICD therapy for ventricular tachyarrhythmias. The follow-up started after ICD implantation. Results Appropriate ICD therapies occurred in 15 (56%) of 27 patients with definite CS, 17 (68%) of 25 with suspected CS, and 16 (32%) of 50 with DCM. The rate of appropriate ICD therapies was higher in patients with definite CS and those with suspected CS than in those with DCM (log-rank test, p = 0.010). After ICD implantation, five or more appropriate ICD therapies occurred in 5 (19%) patients with definite CS and 10 (40%) with suspected CS, but in only 1 (2%) with DCM. Cox proportional hazard analysis showed that CS, including suspected CS, was independently associated with appropriate ICD therapies. For primary prevention, the rate of appropriate ICD therapies was higher in patients with CS than in those with DCM (log-rank test, p = 0.034). More than half of patients with CS received appropriate ICD therapies. Conclusions Patients with CS receive appropriate ICD therapies for ventricular tachyarrhythmias at a higher rate, compared with those with DCM, suggesting that ICD implantation should be performed in patients with CS.