Primary Prevention of Sudden Cardiac Death in Silent Cardiac Sarcoidosis

Abstract

Background— Cardiac involvement in sarcoidosis is often silent and may lead to sudden death. This study was designed to assess the value of programmed electric stimulation of the ventricle (PES) for risk stratification in patients with sarcoidosis and evidence of preclinical cardiac involvement on imaging studies. Methods and Results— Patients with biopsy-proven systemic sarcoidosis but without cardiac symptoms who had evidence of cardiac sarcoidosis on positron emission tomography (PET) or cardiac MRI (CMR) were included. All patients underwent baseline evaluation, echocardiographic assessment of left ventricular function, and programmed electric stimulation of the ventricle. Patients were followed for survival and arrhythmic events. Seventy-six patients underwent PES of the ventricle. Eight (11%) were inducible for sustained ventricular arrhythmias and received an implantable defibrillator. None of the noninducible patients received a defibrillator. Left ventricular ejection fraction was lower in patients with inducible ventricular arrhythmia (36.4±4.2% versus 55.8±1.5%, P <0.05). Over a median follow-up of 5 years, 6 of 8 patients in the group with inducible ventricular arrhythmias had ventricular arrhythmia or died, compared with 1 death in the negative group ( P <0.0001). Conclusions— In patients with biopsy-proven sarcoidosis and evidence of cardiac involvement on PET or CMR alone, positive PES may help to identify patients at risk for ventricular arrhythmia. More importantly, patients in this cohort with a negative PES appear to have a benign course within the first several years following diagnosis. PES may help to guide the use of implantable cardioverter defibrillators in this population.

Cardiac Sarcoid: A Clinician's Review on How to Approach the Patient With Cardiac Sarcoid

“…Only 1 patient died from the 68 whose PES was negative and none had symptomatic VT or required an ICD after 5 years of follow-up. 42 Similarly, in 27 systemic sarcoidosis patients with suspected cardiac involvement, Aizer et al found a hazard ratio, for SCD or ICD shock, of 6.3 (95% confidence interval: 1.81-21.95) in subjects with spontaneous VT. 41 They also found a hazard ratio of 6.97 (95% confidence interval: 1.27-38.27) in patients with inducible VT by PES but no history of spontaneous VT. These studies demonstrate that PES can detect electrically labile myocardium in subclinical CS.…”

“…41,42 Programmed electrical stimulation (PES) has the potential to identify CS patients with electrical instability and may help to determine if patients should get an ICD. 6 Mehta et al studied 76 patients with extracardiac sarcoidosis and found 8 with a positive study, and all had ICDs placed.…”

“…6 Mehta et al studied 76 patients with extracardiac sarcoidosis and found 8 with a positive study, and all had ICDs placed. 42 Of these 8, 4 received appropriate shocks and 2 died of SCD. Only 1 patient died from the 68 whose PES was negative and none had symptomatic VT or required an ICD after 5 years of follow-up.…”

Magnetic Resonance Imaging for Identifying Patients With Cardiac Sarcoidosis and Preserved or Mildly Reduced Left Ventricular Function at Risk of Ventricular Arrhythmias

“…A recent study by Mehta et al 16 evaluated electrophysiological testing for risk stratification in patients with asymptomatic CS. In that study, the majority of patients with inducible VT had a reduced LVEF, and therefore, the patient population at risk was different than in the present study.…”

Is There an Association Between Clinical Presentation and the Location and Extent of Myocardial Involvement of Cardiac Sarcoidosis as Assessed by 18 F- Fluorodoexyglucose Positron Emission Tomography?

“…22 The decision regarding ICD insertion is hampered by limited tools for patient risk stratification and a lack of knowledge regarding the true prevalence of ventricular arrhythmia in this population. Programmed ventricular stimulation has been shown to have some use in this regard, [23][24][25] but there are limited studies in this area and the long-term prognostic significance of a normal study remains unclear.…”