Comparison of cardiac function between right ventricular septal pacing and right ventricular apex pacing

AIM: To compare the cardiac function between right ventricular septal pacing and right ventricular apex pacing. METHODS: A total of 180 cases were randomly divided into ventricular septal pacing group (n=98 cases) and apex pacing group (n=82). Changes in the echocardiogram of the two groups were compared before surgery and 1.5 years after surgery. RESULTS: Left ventricular ejection fraction (LVEF) in septal group increased ［(66±8)% vs.(69±9)%, P<0.01］, stroke volume (SV) increased ［(83±1)ml vs.(87±12)ml, P<0.01］, left ventricular end-diastolic diameter (LVEDD) decreased ［(52±5)mm vs.(51±5)mm］, and no significant change was found in left ventricular end-systolic diameter (LVESD) ［(31±5)mm vs.(31±5)mm］. In apex group, LVEF significantly decreased ［(68±7)% vs.(63±8)%, P<0.01］, SV significantly decreased ［(87±16) ml vs.(80±10) ml, P<0.01］, and a significant increase was found in LVEDD ［(50±6)mm vs.(53±7)mm, P<0.01］ and in LVESD ［(30±5)mm vs.(32±6)mm, P<0.05］. Eighteen months after operation, LVEF (P<0.01) and SV (P<0.05) were significantly different between groups. Pre- and postoperative difference between groups was statistically significant (P<0.05). CONCLUSION: Ventricular septal pacing is superior to right ventricular apex pacing in improving cardiac function in patients with pacemaker implant.