Cardiomyopathy With Frequent Ventricular Premature Depolarization　– Predicting Irreversible Ventricular Dysfunction –

BACKGROUND: High ventricular premature depolarization (VPD) burden is associated with left ventricular (LV) dysfunction that typically resolves after successful ablation. Some patients, however, have persistent LV dysfunction, even after successful radiofrequency (RF) ablation. Identifying factors associated with irreversibility of LV cardiomyopathy (CMP) may help predict clinical outcome. METHODS AND RESULTS: Patients with frequent VPD (>10%/day) who underwent successful VPD suppression were divided into 2 groups according to transthoracic echocardiography (TTE) before and after suppression: group A (n=38) had depressed LV function that normalized after VPD suppression; group B (n=19) had depressed LV function before and after suppression. Of 57 patients (43 men; mean age, 54±15 years), RF ablation was performed in 39. Clinical, electrocardiographic, and TTE parameters were compared between groups. LV end-diastolic dimension (LVEDD; group A vs. B: 54±5 mm vs. 60±10 mm, P=0.01), end-systolic dimension (group A vs. B: 42±6 mm vs. 48±11 mm, P=0.01) before VPD suppression differed significantly between groups. Pre-suppression LVEDD was ≤66 mm in all reversible-CMP patients. LVEDD >66 mm predicted irreversible CMP with 50% sensitivity, 100% specificity, 100% positive predictive value, and 81% negative predictive value. CONCLUSIONS: LVEDD was a good predictor of irreversible LV CMP with frequent VPD, with 50% sensitivity and 100% specificity.