Effects On Hemodynamics When Pacing In Right Ventricular Septum Assisted With Program And Optimization

【Objective】To compare the effects on hemodynamics when pacing in right ventricular septum and in right ventricular apex. Patients in the two groups were programmed and modified after operation to explore the feasibility study of the most optimization pacing.【method】: Forty-eight patients with sick sinous syndrome ( SSS ) and twenty patients with completely atrioventricularblock, amount to sixty-eight patients performed with DDD pacing were grouped randomly into two terms according to the site where the ventricular pacing lead fixed, one group received right ventricular septum(RVS) pacing while the other group received right ventricular apex(RVA) pacing. The QRS waves of the ECG,the left ventricular ejection fraction(LVEF), the cardiac index(CI),the stroke volume(SV)and plasma levels of brain natriuretic peptide (BNP) were compared among preoperation and postoperation. Patients with SSS in the two groups were programmed and modified three months after operation. Hemodynamics parameters and plasma levels of BNP were recorded and analyzed in the next three months. 【Consequence】:1. The QRS duration of leadⅡof RVS group was shorter than RVA group dramatically( P<0.05 ).2. There were no defference on LVEF,CI,SV and plasma levels of BNP of the two groups before operation. Compared with the hemodynamics and plasma levels of BNP of the RVS groups, the LVEF, CI, SV of the RVA groups of three months after operation decreased significantly (P<0.05 ), but the plasma levels of BNP increased notably(P<0.01).3. Comared with the same parameters of patients with SSS of RVA groups, the LVEF, CI, SV of three months after program and optimization increased remarkably(P<0.05), while the plasma levels of BNP decreased obviously(P<0.01), but still higher than those of preoperation evidently (P<0.05).4. To those patients with SSS of RVS groups,there were no defference on LVEF,CI,SV of three months after program and optimization(p>0.05),however the plasma levels of BNP decreased remarkably(P<0.05),but there were no difference when compared with those of preoperation(p>0.05).【Conclusion】:1. The RVA pacing disturbs the biventricular electrical synchrony and results in the deterioration of the hemodynamics. The RVS pacing farthest keeps the normal sequence of electrical activity and the synchronous contraction and has no negative effect on the hemodynamics. The RVS pacing is more physiological than the RVA pacing.2. Right ventricular pacing reduced substantially when patients with SSS of RVS groups were programmed and modified, and then the pacing way will be more reasonable and expectant to the most optimization pacing.