الفهرس | Only 14 pages are availabe for public view |
Abstract Premature ventricular contractions (PVCs) are common and occur in a broad spectrum of the population. This includes patients without structural heart disease and those with any form of cardiac disease, independent of severity. Ventricular premature beats produce few or no symptoms in the vast majority of patients, although occasional patients are incapacitated by palpitations or dizziness. PVCs rarely cause true hemodynamic compromise except in patients with frequent PVCs and severely depressed left ventricular function or when they are concurrent with a bradycardia. This randomized clinical study included 50 patients with frequent symptomatic PVCs with no underlying cause, including 17 (34%) females and 33 (66%) males. The patients were selected as out-patients of national heart institute during the period between September 2007 and September 2009. Patients with curable etiology for PVCs were excluded from the study. The patients were randomized into two groups: Group (I) included 25 patients who received mexiletine in a dose of 200mg every 8 hours for one week. Group (II) included 25 patients who received atenolol in a dose of 50 mg once daily for one week. All patients were monitored for 24- hours with a Holter recorder using 3 channel Burdick visionTM 5L, with digital solid state recorder. Results: On 24 h Holter recording, number of PVCs was 6856.34±6475 (median 3410) in group I, and 4223.65±5947.04 (median 1184) in group II. There was no significant difference between the 2 groups in age, sex, symptoms, and Holter findings. After treatment, there was 69.8% reduction of symptoms in group I, and 97% in group II (p=0.0001). On 24 h Holter recording, total number of PVCs decreased by -4875.1±5911.86 (median -2627) in group I and -4142.95±5894.39 (median -1177) in group II (p=0.64). Percentage of PVCs to total recorded beats decreased by -4.31±5.39% (median -2.15%) in group I, and -3.75±5.7% (median -0.9%) in group II (p=0.8). Atenolol significantly decreased the number of PACs (p=0.009) while mexiletine did not affect the number of PACs. Both drugs were well tolerated with no reported adverse effects. Conclusion: Mexiletine is effective in the treatment of symptomatic, idiopathic PVCs, and is well tolerated in apparently healthy individuals, with results comparable to atenolol. Atenolol obtained better symptomatic improvement than mexiletine, probably due to its ability to suppress PACs. |