Heart Research Follow-up Program, Division of Cardiology, Department of Medicine at the University of Rochester Medical Center, Rochester, New York; Heart Institute, Sheba Medical Center, Ramat Gan, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
Heart Research Follow-up Program, Division of Cardiology, Department of Medicine at the University of Rochester Medical Center, Rochester, New York; Heart Institute, Sheba Medical Center, Ramat Gan, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
J Am Coll Cardiol. 2016 Jan 26;67(3):303-12. doi: 10.1016/j.jacc.2015.10.076.
Relative wall thickness (RWT), defined as 2 times posterior wall thickness divided by the left ventricular (LV) diastolic diameter, is a measure of LV geometry and may be a marker for adverse events in patients with LV dysfunction.
The aim of this study was to investigate the relationship between RWT and the risk for ventricular tachyarrhythmia (VA) in patients enrolled in the MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy) study.
The study population comprised 1,260 patients with mild heart failure and left bundle branch block.
In a multivariable model, RWT was the most powerful echocardiographic measure for estimating the risk of VAs compared with commonly used echocardiographic variables. Patients with low RWT (<0.24) had 83% (p < 0.001) increased risk for VA and 68% (p < 0.001) increase in VA risk or death (VA/death) compared with patients with higher RWT values. Each 0.01-unit decrease in RWT was associated with 12% (p < 0.001) and 10% (p < 0.001) increases in the risk of VA and VA/death, respectively. Treatment with cardiac resynchronization therapy with defibrillator (CRT-D; CRT with implantable cardioverter-defibrillator) was associated with a greater increase in RWT compared with implantable cardioverter-defibrillator at 12 months (4.6 ± 6.8% vs. 1.5 ± 2.7%; p < 0.001), and every 10% increase in RWT in CRT-D patients was associated with 34% (p = 0.027) and 36% (p = 0.009) reductions in the risk of subsequent VA and VA/death, respectively.
In patients with mild heart failure and left bundle branch block, decreased RWT was associated with an increase in the risk of VA and VA/death. CRT-D therapy was associated with a favorable increase in RWT and reduction in risk of VA and VA/death. (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy [MADIT-CRT]; NCT00180271).
相对壁厚度（RWT）定义为后壁厚度的 2 倍除以左心室（LV）舒张直径，是衡量 LV 几何形状的指标，可能是 LV 功能障碍患者不良事件的标志物。
本研究旨在探讨 MADIT-CRT（多中心自动除颤器植入试验与心脏再同步治疗）研究中入选患者的 RWT 与室性心动过速（VA）风险之间的关系。
研究人群包括 1260 名患有轻度心力衰竭和左束支传导阻滞的患者。
在多变量模型中，与常用的超声心动图变量相比，RWT 是预测 VA 风险的最有力的超声心动图指标。RWT 较低（<0.24）的患者发生 VA 的风险增加 83%（p<0.001），VA 风险或死亡（VA/死亡）增加 68%（p<0.001），与 RWT 值较高的患者相比。RWT 每降低 0.01 个单位，VA 风险分别增加 12%（p<0.001）和 10%（p<0.001），VA/死亡风险分别增加 10%（p<0.001）和 10%（p<0.001）。与植入式心脏复律除颤器（ICD）相比，心脏再同步治疗除颤器（CRT-D）治疗 12 个月时 RWT 增加更大（4.6±6.8%对 1.5±2.7%；p<0.001），并且 CRT-D 患者的 RWT 每增加 10%，VA 风险分别降低 34%（p=0.027）和 36%（p=0.009），VA/死亡风险分别降低。
在轻度心力衰竭和左束支传导阻滞患者中，RWT 降低与 VA 风险和 VA/死亡风险增加相关。CRT-D 治疗与 RWT 的有利增加和 VA 和 VA/死亡风险的降低相关。（多中心自动除颤器植入试验与心脏再同步治疗[MADIT-CRT]；NCT00180271）。
