RESUMO
BACKGROUND: Current guidelines present varying classes of recommendations for implantable cardioverter-defibrillator (ICD) utilization in patients with cardiac sarcoidosis (CS) and left ventricular ejection fraction (LVEF) <50%. OBJECTIVE: To investigate the ventricular arrhythmia risk in CS patients with ICDs and varying degrees of LV systolic dysfunction. METHODS: We included CS patients with an ICD and LVEF <50% at index evaluation. The primary outcome was survival free of sustained ventricular tachycardia/fibrillation (VT/VF) after ICD implantation and was assessed comparatively for LVEF ≤35 vs 36-49% and for primary vs secondary prevention ICD indication. RESULTS: We included 61 patients (median age 57 years, 61% male) with LVEF 36-49% (n=23) or LVEF ≤35% (n=38). An ICD was implanted for secondary prevention in 24% and 44% of the LVEF ≤35% and 36-49% groups, respectively (p=0.11). The primary outcome did not differ between the two groups in univariable analysis (LVEF ≤35% vs 36-49% HR 0.85 [95% CI 0.39, 1.82], p=0.67). In multivariable analysis, secondary prevention ICD indication was the only significant predictor of incident sustained VT/VF (HR 2.86 [95% CI 1.23, 6.67], p=0.015). The mean sustained VT/VF event burden was higher in the secondary as compared with the primary prevention ICD patients (0.47 vs 0.11 events/patient-year, p=0.005) but did not differ significantly between LVEF ≤35% and 36-49% patients. CONCLUSIONS: CS patients with ICD indications and LVEF 36-49% carry similarly high arrhythmic risk as those with LVEF ≤35%. Patients with secondary prevention ICDs have the highest overall risk.
RESUMO
BACKGROUND: The 2014 Heart Rhythm Society consensus statement defines histological (definite) and clinical (probable) diagnostic categories of cardiac sarcoidosis (CS), but few studies have compared their arrhythmic phenotypes and outcomes. OBJECTIVE: The purpose of this study was to evaluate the electrophysiological/arrhythmic phenotype and outcomes of patients with definite and probable CS. METHODS: We analyzed the arrhythmic/electrophysiological phenotype in a single-center North American cohort of 388 patients (median age 56 years; 39% female, n = 151) diagnosed with definite (n = 58) or probable (n = 330) CS (2000-2022). The primary composite outcome was survival to first ventricular tachycardia/fibrillation (VT/VF) event or sudden cardiac death. Key secondary outcomes were also assessed. RESULTS: At index evaluation, in situ cardiac implantable electronic devices and antiarrhythmic drug use were more common in definite CS. At a median follow-up of 3.1 years, the primary outcome occurred in 22 patients with definite CS (38%) and 127 patients with probable CS (38%) (log-rank, P = .55). In multivariable analysis, only a higher ratio of the 18F-fluorodeoxyglucose maximum standardized uptake value of the myocardium to the maximum standardized uptake value of the blood pool (hazard ratio 1.09; 95% confidence interval 1.03-1.15; P = .003, per 1 unit increase) was associated with the primary outcome. During follow-up, patients with definite CS had a higher burden of device-treated VT/VF events (mean 2.86 events per patient-year vs 1.56 events per patient-year) and a higher rate of progression to heart transplant/left ventricular assist device implantation but no difference in all-cause mortality compared with patients with probable CS. CONCLUSION: Patients with definite and probable CS had similarly high risks of first sustained VT/VF/sudden cardiac death and all-cause mortality, though patients with definite CS had a higher overall arrhythmia burden. Both CS diagnostic groups as defined by the 2014 Heart Rhythm Society criteria require an aggressive approach to prevent arrhythmic complications.