Electrocardiographic characteristics in patients with sarcoidosis

Background: Several studies have emphasized on the importance of early identification of cardiac sarcoidosis. Aim of our study is the evaluation of electrocardiographic (ECG) characteristics in a cohort of sarcoidosis patients indicating myocardial involvement. Methods: Consecutive patients with biopsy proven sarcoidosis (n=315) were examined from October 2002 through October 2011. Exclusion criteria were presence of pacemaker and/or implantable cardioverter defribrillator. Heart rate (HR), PQ, QRS, QT and QT corrected intervals, P,QRS and T wave axis were collected. Also, complete and incomplete right (RBBB) and left (LBBB) bundle branch block, right (RVH) and left (LVH) ventricular hypertrophy, repolarization and intraventricular abnormalities were noted. Results: Only 59 out of 315 patients had a normal ECG. Mean HR was 75±13.5 beats/min, QT=390±33ms, QTc=417.58±21.2ms while axis of P, QRS and T wave was: 42.65±19.86°, 20.79±34.06° and 34.74±25.92°, respectively. Six patients were found at atrial fibrillation while the rest were at sinus rhythm. PQ interval was 156.89±24.91 ms and the QRS interval was 97.34±17.56 msec. RBBB was detected in 55 (11 complete and 44 incomplete) and LBBB in 9 patients (8 complete and 1 incomplete). Sixty patients were found with ventricular hypertrophy (56 LVH/4 RVH). At least at one lead repolarisation abnormality was found in 177 patients including inferior lead abnormalities at 28, anterior leads abnormalities at 23 and lateral leads abnormalities at 23 patients. Conclusion: Although ECG is a widely available tool used in the diagnosis of cardiac sarcoidosis various abnormalities were described implying necessity of extensive investigation in order to detect cardiac involvement.