Clinical and Imaging Abnormalities Associated With Inducible Ventricular Arrhythmias During Electrophysiologic Study in Patients With Cardiac Sarcoidosis and Mildly Impaired Left Ventricular Function.

BACKGROUND

Patients with cardiac sarcoidosis (CS) and mildly impaired left ventricular ejection fraction remain at high risk for sudden cardiac death. However, risk stratification for implantable cardioverter-defibrillator implantation in this group is needed. We aimed to determine if electrophysiologic study (EPS) may be used as a noninvasive alternative for sudden cardiac death risk stratification.

METHODS

In this retrospective cohort study, we analyzed patients with CS (aged >18 years) with highly probable or probable sarcoidosis according to the World Association of Sarcoidosis and Other Granulomatous Disorders Sarcoidosis Organ Assessment Instrument, with evidence of late gadolinium enhancement on cardiac magnetic resonance imaging in a pattern consistent with CS and left ventricular ejection fraction ≥40%, who underwent EPS.

RESULTS

We identified 101 patients with CS, 15 EPS positive and 86 EPS negative. A higher proportion of patients with an EPS-positive study was associated with antiarrhythmic therapy (P=0.005) and ventricular tachycardia on ECG or Holter monitoring (P<0.001). In multivariable analysis, transmural myocardial scarring (odds ratio, 3.78 [95% CI, 1.05-14]; P=0.041) and edema on T2-weighted cardiac magnetic resonance imaging (odds ratio, 4.75 [95% CI, 1.09-21.2]; P=0.036) were associated with higher odds of an EPS-positive study. There was no association between anatomic distribution of scar within left ventricular and right ventricular segments and inducibility on EPS.

CONCLUSIONS

In patients with CS and mildly impaired left ventricular ejection fraction, we demonstrated that transmural myocardial scarring and edema on T2-weighted cardiac magnetic resonance imaging are associated with sustained ventricular arrhythmia during EPS, suggesting that noninvasive imaging features may be used as prognostic indicators in patients with CS. Larger, prospective studies are needed to inform implantable cardioverter-defibrillator implantation guidelines.