Reduction in coronary microvascular resistance through cardiac resynchronization and its impact on chronic reverse remodelling of left ventricle in patients with non-ischaemic cardiomyopathy
Reduction in coronary microvascular resistance through cardiac resynchronization and its impact on chronic reverse remodelling of left ventricle in patients with non-ischaemic cardiomyopathy
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DOI：
10.1093/europace/euu361
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发表时间：
2015-09-01
期刊：
影响因子：
6.1
通讯作者：
Hirata, Ken-ichi
中科院分区：
文献类型：
--
作者：
Itoh, Mitsuaki;Shinke, Toshiro;Hirata, Ken-ichi
左束支传导阻滞(LBBB)导致机械不同步，从而影响非缺血性心肌病的冠脉循环。我们试图检测心脏再同步化治疗(CRT)对冠状动脉血流动力学和左心室(LV)功能的影响。纳入22名非缺血性心肌病患者(纽约心脏协会分级III或IV级；LV射血分数，千分之35%；QRS持续时间，千分之130毫秒)。植入CRT装置1周后，分别采用序贯心房和双室起搏(BIV)和心房起搏(LBBB)和序贯房室传导阻滞(CK)两种起搏方式，对冠脉左前降支(LAD)和左回旋支(LCx)的血流速度和压力进行无创性测量。我们评估了充血微血管阻力(HMR，平均远端压除以充血平均峰值速度)，以及HMR的变化和中期LV反向重构之间的关系。BIV组充血微血管阻力低于对照组(LAD：1.76+/-0.47vs.1.54+/-0.45，P=0.001；Lcx：1.92+/-0.42vs.1.73+/-0.31，P=0.003)。心脏再同步化治疗通过减少微血管阻力改善冠脉血流循环，其机制可能与心脏再同步治疗前和术后6个月左心室射血分数(R=-0.598，P=0.011)和左心室收缩末期容量(R=0.609，P=0.010)的变化有关。
Left bundle branch block (LBBB) induces mechanical dyssynchrony, thereby compromising the coronary circulation in non-ischaemic cardiomyopathy. We sought to examine the effects of cardiac resynchronization therapy (CRT) on coronary flow dynamics and left ventricular (LV) function.Twenty-two patients with non-ischaemic cardiomyopathy (New York Heart Association class, III or IV; LV ejection fraction, a parts per thousand currency sign35%; QRS duration, a parts per thousand yen130 ms) were enrolled. One week after implantation of the CRT device, coronary flow velocity and pressure in the left anterior descending coronary artery (LAD) and left circumflex coronary artery (LCx) were measured invasively, before and after inducing hyperemia by adenosine triphosphate administration, with two programming modes: sequential atrial and biventricular pacing (BiV) and atrial pacing in patients with LBBB or sequential atrial and right ventricular pacing in patients with complete atrioventricular block (Control). We assessed hyperemic microvascular resistance (HMR, mean distal pressure divided by hyperemic average peak velocity) and the relationship between the change in HMR and mid-term LV reverse remodelling. Hyperemic microvascular resistance was lower during BiV than during Control (LAD: 1.76 +/- 0.47 vs. 1.54 +/- 0.45, P < 0.001; LCx: 1.92 +/- 0.42 vs. 1.73 +/- 0.31, P = 0.003). The CRT-induced change in HMR of the LCx correlated with the percentage change in LV ejection fraction (R = -0.598, P = 0.011) and LV end-systolic volume (R = 0.609, P = 0.010) before and 6 months after CRT.Cardiac resynchronization therapy improves coronary flow circulation by reducing microvascular resistance, which might be associated with LV reverse remodelling.