Follow-Up of Cardiac Sarcoidosis by Magnetic Resonance Imaging
A 27-year-old patient presented with a chief complaint of 2 months of increasing dyspnea, vertigo, and performance decline on exertion. The physical examination and echocardiography results were unremarkable. Admission chest radiograph revealed bilateral hilar adenopathy Figure 1. An ECG showed borderline first-degree atrioventricular block. Heart rate at baseline was 68 bpm. During a stress test, atrioventricular conduction abnormalities progressed until complete heart block resulted, and the heart rate decreased to 35 bpm Figure 2. Magnetic resonance imaging (MRI) of the heart showed (on T1-weighted images after application of 0.1 mmol/kg body weight gadolinium diethylenetriamine pentaacetic acid [Gd-DTPA]) multiple, well-demarcated, contrast-enhanced granulomas Figure 3; corresponding wall thickening on gradient-echo images Figure 4; and severe edema associated with granulomatous inflammation on T2-weighted images Figure 5 within the posterior, lateral, and anteroseptal left ventricular walls. Sarcoidosis was confirmed by lymph node biopsy. On follow-up 6 months later after initiation of steroid therapy (prednisolone 1 mg/kg body weight initially for 6 weeks, then a consecutive reduction to 0.25 mg/kg body weight), the patient was asymptomatic. On MRI the contrast-enhanced areas were diminished Figure 6, and no edema was found on T2-weighted images, corresponding to postinflammatory scarring.
Myocardial sarcoid was first reported by Bernstein et al1 in 1929. Clinical manifestations are arrhythmias, conduction disturbances, heart block, pericardial effusion, and sudden death. Clinically recognizable involvement of the heart occurs in ≈5% of patients. The prevalence of direct involvement is estimated to be 20% to 27% in autopsy series. Cardiac MRI is a useful noninvasive method for early diagnosis and follow-up of cardiac sarcoidosis.