Abstract 2856: Prognostic Significance of Frequent Type of Ventricular Arrhythmias Originating From The Right Ventricular Outflow Tract (RVOT).
Background: Recently, the frequent premature ventricular contractions (PVC) originating from the right ventricular outflow tract (RVOT) has been reported to be able to concern with idiopathic VT/VF or bradycardia induced heart failure. However, long-term prognosis of the patients with RVOT-PVC without structural heart disease is unclear. In this study, a prospective long-term observation was performed in patients with frequent RVOT-PVC.
Methods: 278 consecutive patients presenting RVOT-PVC without detectable heart disease were followed up for 3–20 (5.2±3.6) years. 39/278 patients with sustained VT, history of syncope or heart failure at the baseline were treated with the catheter ablation and they were excluded. All patients underwent echo-cardiogram and 24-hour Holter monitoring at the baseline, and 128/239 patients underwent cardiac magnetic resonance image (MRI) to deny degeneration of the right ventricular tissue. Echo-cardiogram and Holter monitoring was repeated every year and the appearance of new symptom, tachycardia or heart failure episode was checked carefully.
Results: At the baseline check, no patient exhibited structural heart disease in echo-cardiogram or MRI. During the observation period of 5.2±3.6 years, no patient exhibited new onset VT/VF or heart failure. Incidence of non-sustained VT (>triplet) was 48/239 at the baseline and 59/239 at the latest Holter monitoring (NS). Total number of PVC was 12,289±11,089 at the baseline and 13,568±12,288 at the latest Holter monitoring (NS). The left ventricular ejection fraction (LVEF) was 64±7% at the baseline and 63±8% at the latest echo-cardiogram (NS). When patients were divided into 3 groups by the PVC number (<5,000, 5,000 –20,000, and >20,000/day), LVEF was unchanged in groups with less frequent PVC (<5,000 and 5,000 –20,000) but was slightly decreased in patients with PVC>20,000 (from 63±7% to 61±8%, p=0.048).
Conclusions: The prognosis of the patients with RVOT-PVC was considered relatively benign when patients with VT/VF or heart failure were excluded at the baseline evaluation. However, the progression of heart failure should be paid an attention in relatively long-term observation especially in patients with frequent PVCs.