Laurenzi Francesco, Achilli Augusto, Avella Andrea, Peraldo Carlo, Orazi Serafino, Perego Giovanni B, Cesario Antonio, Valsecchi Sergio, De Santo Tiziana, Puglisi Andrea, Tondo Claudio
S. Camillo Hospital, Rome, Italy.
Pacing Clin Electrophysiol. 2007 Sep;30(9):1096-104. doi: 10.1111/j.1540-8159.2007.00819.x.
There are few studies on cardiac resynchronization therapy (CRT) in heart failure (HF) patients with preexisting right ventricular (RV) pacing. The purpose of this study was to determine the efficacy of CRT upgrading in RV-paced patients and the predictivity of electromechanical dyssynchrony parameters (EDP) evaluated by standard echocardiography (ECHO) and tissue Doppler imaging (TDI).
Thirty-eight consecutive patients with HF [New York Heart Association (NYHA) class III or IV, LVEF < 35%], prior continuous RV pacing, and absence of atrial fibrillation were enrolled in the presence of a paced QRS > or = 150 ms and evaluated by ECHO and TDI. A responder was defined as a patient with a favorable change in NYHA class and neither HF hospitalization nor death, plus an absolute increase of LVEF > or = 10 units.
At six-months follow-up, the whole study population had significant improvement in symptoms, systolic function, and QRS duration (P < 0.001); 32 (84%) patients had a favorable clinical outcome, 25 (66%) were considered responders according to the previous definition. Postimplant QRS was similarly reduced in both responders and nonresponders, whereas EDP had a significant improvement only in responders (P < 0.05). Using EDP, 23 (79%) patients were responders compared with 2 (22%) patients without mechanical dyssynchrony (P = 0.002).
In HF patients with previous RV pacing, CRT is effective to improve clinical, functional outcome, and LV performance and to reduce electromechanical dyssynchrony in a large proportion of patients. Dyssynchrony evaluated by standard and TDI ECHO can be useful for CRT selection of paced patients.
关于心脏再同步治疗（CRT）在已有右心室（RV）起搏的心力衰竭（HF）患者中的研究较少。本研究的目的是确定CRT升级对RV起搏患者的疗效以及通过标准超声心动图（ECHO）和组织多普勒成像（TDI）评估的机电不同步参数（EDP）的预测价值。
连续纳入38例HF患者[纽约心脏协会（NYHA）心功能分级为III或IV级，左心室射血分数（LVEF）<35%]，既往有持续RV起搏且无房颤，起搏QRS≥150 ms，并通过ECHO和TDI进行评估。有反应者定义为NYHA心功能分级有良好变化、未发生HF住院或死亡且LVEF绝对值增加≥10个单位的患者。
在6个月的随访中，整个研究人群的症状、收缩功能和QRS时限均有显著改善（P<0.001）；32例（84%）患者有良好的临床结局，25例（66%）根据先前定义被视为有反应者。植入后QRS在有反应者和无反应者中均有类似程度的缩短，而EDP仅在有反应者中有显著改善（P<0.05）。使用EDP，23例（79%）患者为有反应者，而无机械不同步的患者中有2例（22%）为有反应者（P = 0.002）。
在既往有RV起搏的HF患者中，CRT可有效改善临床、功能结局及左心室性能，并在很大一部分患者中减少机电不同步。通过标准和TDI ECHO评估的不同步可有助于选择接受CRT治疗的起搏患者。
