Objectives: To evaluate the response to cardiac resynchronization therapy (CRT) and the correlation between CRT and pulmonary artery hemodynamic parameters.
Methods: The patients with chronic heart failure indicator for CRT were enrolled. The left ventricular end-systolic volume (LVESV) was measured by echocardiography and New York Heart Association (NYHA) classification was evaluated between one week before and six months after CRT. Mean pulmonary artery pressure (mPAP), pulmonary artery systolic pressure (PASP) and pulmonary vascular resistance (PVR) were measured by right heart catheterization. Left ventricular reverse remodeling (LVRR) is defined as a decrease of 15% or more in LVESV at the 6th month after CRT; Clinical response is defined as a decrease of NYHA classification at or above grade 1 at the 6th month after CRT. Pulmonary hypertension (PH) was defined as mPAP≥25 mmHg. According to the response, patients were divided into 3 groups: group A (LVRR+clinical response), group B (no LVRR+clinical response) and group C (no LVRR+no clinical response). The changes of NYHA classification, echocardiographic and pulmonary hemodynamic parameters were observed in the 3 groups. The Kaplan-Meier survival curve was used to analyze the differences in all-cause mortality, combined end-point events of death or re-hospitalization due to heart failure among different groups.
Results: A total of 45 patients with CRT implantation [aged (63.27±9.55) years, 36 males] were included. The average follow-up period was (33.76±11.50) months. Thirty-one patients (68.89%) were in group A, 9 of whom with PH. Eight patients (17.78%) were in group B, 7 of whom with PH. Six patients were in group C, all with PH. Cardiac function including NYHA classification, echocardiographic and pulmonary hemodynamic parameters had been significantly improved in group A after CRT implantation (P<0.05). In group B, NYHA classification and pulmonary hemodynamic parameters were decreased significantly (P<0.05), but echocardiographic parameters did not change obviously (P>0.05). There were no significant changes in NYHA classification, echocardiographic and pulmonary hemodynamic parameters in group C (P>0.05). Compared with group C, group A and group B had lower all-cause mortality (P=0.005) and lower incidence of composite endpoint events (P=0.001).
Conclusions: Patients with LVRR and clinical response after CRT have a good prognosis. Patients with clinical response but without LVRR have a better prognosis than those without clinical response and LVRR, which may be related to the decrease of pulmonary hemodynamic parameters such as mPAP and TPG.
目的: 评价心脏再同步化治疗(cardiac resynchronization therapy，CRT)的反应性及其与肺动脉血流动力学参数之间的关系。方法: 纳入符合CRT植入适应证的慢性心力衰竭患者，CRT术前1周和术后6个月采用纽约心脏协会(New York Heart Association，NYHA)心功能分级和超声心动图测定左心室收缩末容积(left ventricular end-systolic vulume，LVESV)评价心功能状态，采用右心导管检查测定平均肺动脉压力(mean pulmonary artery pressure，mPAP)、肺动脉收缩压(pulmonary artery systolic pressure，PASP)、肺动脉血管阻力(pulmonary vascular resistance，PVR)等血流动力学参数。左心室逆转重构(left ventricular reverse remodeling，LVRR)定义为CRT术后6个月LVESV较术前下降15%或以上；临床反应性定义为CRT术后6个月NYHA心功能分级降低≥1级以上；肺动脉高压(pulmonary hypertension，PH)定义为mPAP≥25 mmHg。根据反应性不同分为3组：A组(LVRR+临床反应性)；B组(无LVRR+临床反应性)；C组(无LVRR+无临床反应性)。观察各组术前和术后LVESV，NYHA心功能分级和肺动脉血流动力学参数的变化。采用Kaplan-Meier生存曲线分析各组全因死亡率、死亡或心力衰竭再住院的复合终点事件率之间的差异。结果: 纳入45例CRT患者，男36例，女9例，年龄(63.27±9.55)岁；随访(33.76±11.50)个月。A组31例(68.89%)，其中PH 9例(9/31)；B组8例(17.78%)，其中PH 7例(7/8)；C组6例，均为PH(6/6，100%)。与术前比较，A组NYHA心功能分级降低，左心室射血分数(left ventricular ejection fraction，LVEF)升高，左心室收缩末期容积(left ventricular end systolic volume，LVESV)降低，同时伴有PASP，mPAP和PVR降低，其变化差异均有统计学意义(P<0.05)；B组NYHA心功能分级明显降低(P<0.05)，但LVEF和LVESV变化不明显(P>0.05)，PASP，mPAP和PVR明显降低(P<0.05)；C组NYHA心功能分级、LVEF和LVESV变化不明显(P>0.05)，同时PASP，mPAP，PVR变化也不明显(P>0.05)。与C组比较，A组和B组全因死亡率低(P=0.005)，复合终点事件发生率低(P=0.001)。结论: CRT术后表现LVRR且有临床心功能改善的患者预后佳。术后无LVRR伴临床心功能改善患者可能与肺动脉血流动力学参数mPAP和TPG等降低有关，其临床预后优于术后无LVRR且临床心功能无改善患者。.
Keywords: cardiac resynchronization therapy; heart failure; pulmonary hypertension; response.