Simantirakis Emmanuel N, Vardakis Konstantinos E, Kochiadakis George E, Manios Emmanuel G, Igoumenidis Nikolaos E, Brignole Michele, Vardas Panos E
Cardiology Department, Heraklion University Hospital, PO Box 1352 Stavrakia, Heraklion, Crete, Greece.
J Am Coll Cardiol. 2004 Mar 17;43(6):1013-8. doi: 10.1016/j.jacc.2003.10.038.
The aim of the study was to evaluate whether left ventricular (LV) mechanics are better under LV-based pacing than under right ventricular (RV) apical pacing in patients with permanent atrial fibrillation (AF) after atrioventricular junction (AVJ) ablation.
"Ablate and pace" is an acceptable therapy for drug-refractory AF. However, the RV apical stimulation commonly used seems to interfere with the beneficial hemodynamic effect of regularization of heart rhythm.
The study included 12 patients (5 men, mean age 62 +/- 8.3 years), 6 with impaired and 6 with normal LV systolic function. All of them had a biventricular pacemaker system implanted and underwent atrioventricular node ablation for drug-refractory chronic AF. Using a conductance catheter, we analyzed LV pressure-volume loops during routine coronary angiography in order to evaluate short-term changes in LV mechanics during RV apical and LV-based (LV free wall or biventricular) pacing.
Compared with RV pacing, LV-based pacing significantly improved the indexes of LV systolic function (i.e., end-systolic pressure and volume, cardiac index, stroke work, preload recruitable stroke work, maximal rate of rise of LV pressure [dP/dt(max)], LV ejection fraction, and end-systolic elastance). The LV diastolic filling indexes, end-diastolic pressure and volume, were better during LV-based pacing, whereas LV diastolic function indexes, -dP/dt(max), passive diastolic chamber stiffness, and time constant of LV isovolumic relaxation showed no clear change.
In the short term, LV-based pacing is superior to RV apical pacing in terms of contractile function and LV filling after AVJ ablation for drug-refractory AF.
本研究旨在评估在永久性心房颤动（AF）患者经房室结（AVJ）消融后，基于左心室（LV）起搏时左心室力学功能是否优于右心室（RV）心尖部起搏。
“消融并起搏”是药物难治性AF的一种可接受的治疗方法。然而，常用的RV心尖部刺激似乎会干扰心律规整化的有益血流动力学效应。
本研究纳入12例患者（5例男性，平均年龄62±8.3岁），其中6例LV收缩功能受损，6例正常。所有患者均植入双心室起搏器系统，并因药物难治性慢性AF接受房室结消融。在常规冠状动脉造影期间，我们使用电导导管分析LV压力-容积环，以评估RV心尖部起搏和基于LV（LV游离壁或双心室）起搏期间LV力学功能的短期变化。
与RV起搏相比，基于LV起搏显著改善了LV收缩功能指标（即收缩末期压力和容积、心脏指数、每搏功、可招募前负荷每搏功、LV压力最大上升速率[dP/dt(max)]、LV射血分数和收缩末期弹性）。基于LV起搏时，LV舒张期充盈指标、舒张末期压力和容积更好，而LV舒张功能指标、-dP/dt(max)、被动舒张期心室僵硬度和LV等容舒张时间常数无明显变化。
短期内，对于药物难治性AF经AVJ消融后，基于LV起搏在收缩功能和LV充盈方面优于RV心尖部起搏。
