双腔起搏房室延迟优化对心功能及神经内分泌因子的影响

观察双腔起搏不同房室延迟(AVD)对即刻心功能的影响,并探讨以优化的AVD起搏对心功能及神经内分泌因子的影响。用SwanGanz导管和彩色多谱勒心脏超声仪分别测定20例心功能ⅡⅢ级患者不同AVD起搏时心功能参数的变化,将心排血量(CO)最大的和/或平均肺毛细血管楔嵌压(MPCWP)下降最明显的AVD定为优化AVD。其后,所有患者分别进行8周常规AVD及8周优化AVD起搏,分别在8周结束时对患者进行心脏B超测试及测定血浆内皮素(ET)、心钠素(ANP)、肾素活性(PRA)、血管紧张素Ⅱ(AngⅡ)、醛固酮(ALD)。结果:根据心导管及心脏B超测量的优化AVD分别为134±13ms及131±12ms。优化AVD组较常规AVD组对左室收缩功能指标有改善,但未达有统计学显著性差异。左室舒张功能指标在优化AVD组较常规AVD组明显改善。神经内分泌因子在优化AVD组较常规AVD组明显减低。结论:优化AVD起搏对心力衰竭患者远期心功能有改善作用,能明显降低有关神经内分泌因子。

Effects of the Optimal AV Delay of DDD Pacing on Cardiac Function and Neurohormonal Levels in Patients With Congestive Heart Failure

To investigate the acute effects of cardiac function of different AV delays(AVD) during DDD pacing and long-term clinical benefits of dual-chamber pacing with an optimized AVD and neurohormonal reactivation in patients with congestive heart failure (CHF),a Swan-Ganz catheter and a 2-dimension doppler echocardiography were performed to measure an acute hemodynamic parameters in varied AVD. An optimum AVD was identified as the AV delay associated with the greatest increase in cardiac output (CO) and/or the greatest reduction in pulmonary artery capillary wedge pressure (PCWP) compared with baseline and 250ms AVD. Then, all patients underwent a pacing of 8 weeks at the routine AVD and 8 weeks at their individualized optimal AV delay. At the end of each 8-week period,hemodynamic parameters were measured by Doppler echocardiography and endothelin(ET),atrial natriuretic peptide(ANP),plasma renin activity (PRA),angiotensin(AngⅡ),and aldosterone(ALD) were measured in each patient. Results: An optimal AVD that was measured by a Swan-Ganz catheter was 134±13ms and 131±12ms by a doppler echocardiography. Left ventricular systolic function parameters were improved in optimum AVD group,but there was no significant change between two pacing groups. Left ventricular diastolic function parameters were significantly improved in optimum AVD group compared with those in routine AVD group.Neurohormonal levels were significantly decreased in optimum AVD group compared with those in routine AVD group.Conclusion: Pacing with optimum AVD can improve long-term cardiac function and decrease neurohormonal levels in patients with CHF.