Heart and Vascular Institute, University of Pittsburgh, Pittsburgh, Pennsylvania.
Heart and Vascular Institute, University of Pittsburgh, Pittsburgh, Pennsylvania.
Heart Rhythm. 2018 Nov;15(11):1664-1672. doi: 10.1016/j.hrthm.2018.05.027. Epub 2018 May 28.
Patients with nonspecific intraventricular conduction delay (IVCD) benefit less from cardiac resynchronization therapy (CRT) than patients with left bundle branch block (LBBB).
The purpose of this study was to determine whether post-CRT outcome differences in patients with ischemic cardiomyopathy (ICM) relate to intrinsic QRS pattern and/or scar burden.
We analyzed 393 consecutive ICM patients with left ventricular ejection fraction (LVEF) ≤35%, QRS duration >120 ms, and LBBB or nonspecific IVCD who underwent single-photon emission computed tomography myocardial perfusion imaging and CRT-defibrillator implant. We compared scar burden; QRS duration; LVEF change; risk of death, transplant, or ventricular assist device; and risk of appropriate device shocks between LBBB and IVCD patients, using multivariable analyses to determine relative associations between QRS pattern vs scar burden and outcomes.
Nonspecific IVCD is associated with greater scar burden and narrower baseline QRS duration than LBBB. IVCD patients demonstrated less QRS narrowing with CRT than LBBB patients, even when excluding IVCD patients with QRS duration <150 ms. LVEF improved less in patients with IVCD vs LBBB, but only scar burden not QRS morphology or duration was associated with LVEF increase ≥5%. During 39-month follow-up, IVCD was associated with shorter survival free from transplant/ventricular assist device and shorter time to first appropriate device shock. Scar burden but not QRS morphology was independently associated with these outcomes on multivariate analysis.
IVCD is associated with greater scar burden than LBBB in ICM CRT-defibrillator recipients. Scar burden, not QRS pattern, is independently associated with adverse clinical outcomes.
与左束支传导阻滞（LBBB）患者相比，非特异性室内传导延迟（IVCD）患者从心脏再同步治疗（CRT）中获益较少。
本研究旨在确定缺血性心肌病（ICM）患者 CRT 后预后差异是否与固有 QRS 形态和/或瘢痕负荷有关。
我们分析了 393 例连续的左心室射血分数（LVEF）≤35%、QRS 时限>120ms 且存在 LBBB 或非特异性 IVCD 的 ICM 患者，这些患者接受了单光子发射计算机断层心肌灌注成像和 CRT-除颤器植入。我们比较了 LBBB 和 IVCD 患者之间的瘢痕负荷、QRS 时限、LVEF 变化、死亡、移植或心室辅助装置风险以及合适的设备电击风险，使用多变量分析来确定 QRS 形态与瘢痕负荷与结局之间的相对关联。
非特异性 IVCD 与更大的瘢痕负荷和更窄的基线 QRS 时限相关，与 LBBB 相比。即使排除 QRS 时限<150ms 的 IVCD 患者，IVCD 患者的 CRT 后 QRS 变窄也小于 LBBB 患者。与 LBBB 患者相比，IVCD 患者的 LVEF 改善较小，但只有瘢痕负荷而不是 QRS 形态或持续时间与 LVEF 增加≥5%相关。在 39 个月的随访期间，与 LBBB 相比，IVCD 与免于移植/心室辅助装置的生存时间较短和首次适当设备电击的时间较短相关。在多变量分析中，瘢痕负荷而不是 QRS 形态与这些结局独立相关。
在 ICM CRT-除颤器接受者中，IVCD 与 LBBB 相比，瘢痕负荷更大。瘢痕负荷，而不是 QRS 形态，与不良临床结局独立相关。
