Time Course of Recovery of Left Ventricular Systolic Dysfunction in Patients with Premature Ventricular Contraction-Induced Cardiomyopathy

Background Idiopathic ventricular arrhythmias in the form of frequent, monomorphic premature ventricular contractions (PVC) can cause PVC-induced cardiomyopathy (PICMP). The aim of this study was to determine the baseline echocardiographic characteristics and the time course and degree of recovery of left ventricular (LV) systolic dysfunction in patients with PICMP. Methods Study population consisted of 348 consecutive patients (205F/143M, 44 +/- 19 y/o) with frequent PVCs and/or ventricular tachycardia. PICMP was defined as LV ejection fraction (LVEF) of <55% in the absence of any detectable underlying heart disease and improvement of LVEF 15% following treatment of ventricular arrhythmia. Patients with PCIMP underwent transthoracic echocardiography for LV size and function at 1 week and at 13 to 612 months of follow-up. Results Twenty-four patients (8F/16M, 47 +/- 18 y/o) with PICMP with complete echocardiographic data were included in the study. Average baseline LV end-diastolic diameter, LV end-systolic volume, LV mass index, and LVEF were 55.4 +/- 6.8 mm, 69.6 +/- 23.3 mL, 110.2 +/- 28.3 g/m2, and 41 +/- 8.4%, respectively. Mild-to-moderate mitral regurgitation (MR) was present in 13 (54%) patients. Early improvement (25% increase in LVEF at 1-week follow-up compared to baseline) was observed in 13 (54%) patients. Patients with early improvement had higher LVEF at 12 months of follow-up compared to patients without early improvement (58.8 +/- 5.0% vs 52.5 +/- 6.7%, P = 0.019). Conclusions PCIMP is characterized by mild-to-moderate global LV systolic dysfunction with slightly increased LV mass and mild-to-moderate MR. Greatest improvement in LV systolic dysfunction was observed at 1-week follow-up in our study population. Early improvement in LVEF may potentially predict the complete reversibility of LV systolic dysfunction.