Institute of Vascular Medicine and Division of Cardiology, Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China.
JACC Cardiovasc Imaging. 2009 Dec;2(12):1341-9. doi: 10.1016/j.jcmg.2009.07.011.
This study aimed to evaluate the impact of cardiac contractility modulation (CCM) on left ventricular (LV) size and myocardial function.
CCM is a device-based therapy for patients with advanced heart failure. Previous studies showed that CCM improved symptoms and exercise capacity; however, comprehensive assessment of LV structure, function, and reverse remodeling is not available.
Thirty patients (60 + or - 11 years, 80% male) with New York Heart Association (NYHA) functional class III heart failure, ejection fraction <35%, and QRS <120 ms were assessed at baseline and 3 months. LV reverse remodeling was measured by real-time 3-dimensional echocardiography. Using tissue Doppler imaging, the peak systolic velocity (Sm) and peak early diastolic velocity (Em) were calculated for LV function, while the standard deviation of the time to peak systolic velocity (Ts-SD) and the time to peak early diastolic velocity (Te-SD) were calculated for mechanical dyssynchrony.
LV reverse remodeling was evident, with a reduction in LV end-systolic volume by -11.5 + or - 10.5% and a gain in ejection fraction by 4.8 + or - 3.6% (both p < 0.001). Myocardial contraction was improved in all LV walls, including sites remote from CCM delivery (all p < 0.05); hence, the mean Sm of 12 (2.2 + or - 0.6 cm/s vs. 2.5 + or - 0.7 cm/s) or 6 basal LV segments (2.5 + or - 0.6 cm/s vs. 3.0 + or - 0.7 cm/s) were increased significantly (both p < 0.001). In contrast, CCM had no impact on regional or global Em (2.9 + or - 1.3 cm/s vs. 2.9 + or - 1.1 cm/s), whereas Ts-SD (28.2 + or - 11.2 ms vs. 27.9 + or - 12.7 ms) and Te-SD (30.0 + or - 18.3 ms vs. 30.1 + or - 20.7 ms) remained unchanged (all p = NS). Mitral regurgitation was reduced (22 + or - 14% vs. 17 + or - 15%, p = 0.02). Clinically, there was improvement of NYHA functional class (p < 0.001) and 6-min hall walk distance (p = 0.015). A 24-h Holter monitor showed that premature ventricular contractions were not increased during CCM.
CCM improves both global and regional LV contractility, including regions remote from the impulse delivery, and may contribute to LV reverse remodeling and gain in systolic function. Such improvement is unrelated to diastolic function or mechanical dyssynchrony.
本研究旨在评估心脏收缩力调节(CCM)对左心室(LV)大小和心肌功能的影响。
CCM 是一种用于治疗晚期心力衰竭患者的基于设备的疗法。先前的研究表明 CCM 改善了症状和运动能力;然而,LV 结构、功能和逆重构的综合评估尚不可用。
30 名(60 +或-11 岁,80%男性)纽约心脏协会(NYHA)心功能 III 级心力衰竭、射血分数<35%和 QRS<120 ms 的患者在基线和 3 个月时进行评估。使用实时 3 维超声心动图测量 LV 逆重构。使用组织多普勒成像,计算 LV 功能的收缩期峰值速度(Sm)和舒张早期速度(Em),而计算机械不同步的收缩期峰值速度的标准差(Ts-SD)和舒张早期峰值速度的标准差(Te-SD)。
LV 逆重构明显,LV 收缩末期容积减少-11.5 +或-10.5%,射血分数增加 4.8 +或-3.6%(均 p < 0.001)。所有 LV 壁心肌收缩均得到改善,包括远离 CCM 输送部位的部位(均 p < 0.05);因此,12 个(2.2 +或-0.6 cm/s 与 2.5 +或-0.7 cm/s)或 6 个 LV 基底节段(2.5 +或-0.6 cm/s 与 3.0 +或-0.7 cm/s)的平均 Sm 显著增加(均 p < 0.001)。相比之下,CCM 对局部或整体 Em(2.9 +或-1.3 cm/s 与 2.9 +或-1.1 cm/s)没有影响,而 Ts-SD(28.2 +或-11.2 ms 与 27.9 +或-12.7 ms)和 Te-SD(30.0 +或-18.3 ms 与 30.1 +或-20.7 ms)保持不变(均 p = NS)。二尖瓣反流减少(22 +或-14%与 17 +或-15%,p = 0.02)。临床方面,NYHA 心功能分级(p < 0.001)和 6 分钟步行距离(p = 0.015)有所改善。24 小时动态心电图监测显示 CCM 期间室性早搏没有增加。
CCM 可改善整体和局部 LV 收缩力,包括远离脉冲输送部位的区域,并可能有助于 LV 逆重构和收缩功能的提高。这种改善与舒张功能或机械不同步无关。