The Effects On Biventricular Electric Synchrony And Hemodynamics Of Pacing In Right Ventricular Septum And Right Ventricular Apex

Objective:To compare the effects on biventricular electric synchrony hemodynamics in right ventricular septum and right ventricular apex;Method: 20 patients performed with DDD pacing were grouped randomly into two terms, one group including 10 patients received RVS pacing while another group received RVA pacing. The QRS waves of the ECG of the preoperation and the postoperation were recorded and analyzed. The instant pacing parameter and that of follow-up of 6 months after the implanting of leads were compared. The exposuring time of X ray of two group in the implantation of leads were compared. The hemodynamic parameters were compared among preoperation and 6 months after operation.Results: The QRS duration of leadⅡof RVA group was longer than that of RVS group dramatically(0.19±0.02s : 0.12±0.02s, P <0.01);The pacing threshold, impedence and the amplitude of R wave of each group were similar statistically. The exposuring time of X ray of RVA group and RVS group in the implantation of leads were 203.0±127.3S and 581.0±124.7S (P <0.05) respectively. The Left Ventricular Ejection Fraction(LVEF), Cardiac Index(CI),Stroke Volume(SV) and E/A of the two groups when preoperation were similar ( P >0.05 ) . Compared with the hemodynamics of the preoperation, The LVEF, CI,SV and E/A of the RVA groups of 6 months after operation decreased significantly(60.7%±5.9% : 54.8%±6.4% , 2.78±0.31 : 2.49±0.26,81.5±10.0 : 68.6±12.5,1.70±0.48 : 1.20±0.39,P <0.05), while RVA groups didn't change statistically (62.7%±6.4% : 61.1%±5.8%,2.74±0.33 : 2.76±0.25,82.2±9.2 : 78.7±11.5,1.62±0.49 : 1.61±0.40,P >0.05). The LVEF, CI,SV and E/A of RVS groups were higher than RVA groups significantly at the follow-up of 6 months (P <0.05).Conclusion: RVS pacing is as safe and efficient as RVA pacing but is more complicated to be implanted than that of RVA pacing. 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 contraction and has little negative effect on the hemodynamics.