Da Costa Antoine, Thévenin Jérome, Roche Frédéric, Faure Emmanuel, Roméyer-Bouchard Cécile, Messier Marc, Convert Gilles, Barthélemy Jean Claude, Isaaz Karl
Division of Cardiology, University Jean Monnet of Saint-Etienne, Saint-Etienne, France.
Heart Rhythm. 2006 Apr;3(4):406-13. doi: 10.1016/j.hrthm.2005.12.017.
Cardiac resynchronization therapy (CRT) provides benefit for congestive heart failure (CHF), but predictors of the clinical response are debated.
The aim of this prospective study was to assess the predictive role of dobutamine stress echocardiography (DSE) in identifying a suitable candidate for CRT.
From March 2001 to December 2003, 71 CHF patients were prospectively enrolled on the basis of four criteria: New York Heart Association (NYHA) class III and IV; QRS > or =150 ms with a left bundle branch block pattern, and left ventricular ejection fraction (LVEF) < or =35% under optimal medical treatment. The combined endpoints were hospital readmission for class IV CHF, heart transplant (HT), and CHF-related death.
The 67 patients completing the study presented with the following characteristics: age (70 +/- 10 years; 11 women); etiology (idiopathic in 44, ischemic in 23); NYHA class (40 in class III and 27 in class IV); LVEF 26% (+/-5%); QRS duration (190 +/- 28 ms); 6-minute walk test 330 m (+/-108); peak oxygen uptake 10.7 (+/-3.3 mL/kg/min); mitral insufficiency in 42 (> or =III grade); interventricular (IV) delay (62 +/- 21 ms); and intraventricular dyssynchrony in 30 patients. Over the follow-up period of 12.1 +/- 8.7 months, 20 (29.9%) of 67 patients presented with at least one hemodynamic event: hospitalization for CHF in 19 (28%) of 67, HT in 2 (3%) of 67, and CHF death in 7 (10%) 67. Univariate analysis identified NYHA class (P = .03), LVEF (P = .015), IV dyssynchrony before (P = .038) and after CRT (P = .0035), IV delay after CRT (P = .002), 6-minute walk distance (P = .01), and DSE Res+ (P = .008) as significant predictors of clinical events. A receiver operating curve established a cut-off value of 1.25 for the DSE responders (Res+: 34 patients at 10 microg/kg/min infusion rates), and the improvement at the 10 microg/kg/min level was 41% +/- 7% in Res+ and 29% +/- 8% in nonresponders (P<.0001). With a cut-off value of 1.25-fold the LVEF increase, the DSE test exhibits 70% sensitivity, 61.7% specificity, 43.8% positive predictive value, and 82.9% negative predictive value. Cox analysis identified IV dyssynchrony before CRT (P = .01) and DSE Res+ (P = .003) as independent predictive factors.
Independent predictive factors of severe hemodynamic clinical outcome in patients with CRT are IV dyssynchrony and DSE.
心脏再同步治疗（CRT）对充血性心力衰竭（CHF）有益，但临床反应的预测因素仍存在争议。
本前瞻性研究旨在评估多巴酚丁胺负荷超声心动图（DSE）在识别适合CRT治疗患者中的预测作用。
从2001年3月至2003年12月，根据以下四项标准前瞻性纳入71例CHF患者：纽约心脏协会（NYHA）III级和IV级；QRS≥150 ms且呈左束支传导阻滞图形，在最佳药物治疗下左心室射血分数（LVEF）≤35%。联合终点为IV级CHF再次住院、心脏移植（HT）和CHF相关死亡。
完成研究的67例患者具有以下特征：年龄（70±10岁；11例女性）；病因（特发性44例，缺血性23例）；NYHA分级（III级40例，IV级27例）；LVEF 26%（±5%）；QRS时限（190±28 ms）；6分钟步行试验330 m（±108）；峰值摄氧量10.7（±3.3 mL/kg/min）；42例（≥III级）二尖瓣关闭不全；室间（IV）延迟（62±21 ms）；30例患者存在室内不同步。在12.1±8.7个月的随访期内，67例患者中有20例（29.9%）出现至少一次血流动力学事件：67例中有19例（28%）因CHF住院，67例中有2例（3%）接受HT，67例中有7例（10%）CHF死亡。单因素分析确定NYHA分级（P = 0.03）、LVEF（P = 0.015）、CRT前IV不同步（P = 0.038）和CRT后（P = 0.0035）、CRT后IV延迟（P = 0.002）、6分钟步行距离（P = 0.01）和DSE Res+（P = 0.008）是临床事件的重要预测因素。受试者工作特征曲线确定DSE反应者（Res+：10 μg/kg/min输注率时34例患者）的截断值为1.25，Res+在10 μg/kg/min水平的改善为41%±7%，无反应者为29%±8%（P<0.0001）。以LVEF增加1.25倍为截断值，DSE试验的敏感性为70%，特异性为61.7%，阳性预测值为43.8%，阴性预测值为82.9%。Cox分析确定CRT前IV不同步（P = 0.01）和DSE Res+（P = 0.003）为独立预测因素。
CRT患者严重血流动力学临床结局的独立预测因素为IV不同步和DSE。
