速度向量成像技术在心力衰竭患者同步化治疗中的应用

目的研究速度向量成像技术(VVI)在指导心脏再同步化治疗(CRT)患者的筛选、左室电极的植入及评价CRT疗效的临床应用价值。方法药物难治性心力衰竭患者17例,年龄60±13岁,NYHA心功能分级Ⅲ或Ⅳ级,术前均经VVI评价左室内十二节段任2个节段收缩达峰时间的最大差值及标准差,并分析左室内收缩最延迟部位。行CRT治疗,将左室电极植入左心收缩最延迟部位相关的冠状静脉窦分支血管内。分别在术后第1,3个月进行随访。观察CRT治疗后患者心功能分级、超声心动图测定心功能指标,以及VVI评价同步性参数的变化。结果随访3个月,患者心功能分级提高I～II级,6min步行距离由309.77±76.05m增至402.06±87.09m(P<0.05),左室射血分数由0.32±0.04增加至0.42±0.07(P<0.01),二尖瓣返流减少。VVI结果显示室内不同步较术前有明显改善。结论VVI技术可用于评价心脏的同步化状态、指导CRT的治疗及评价疗效。

The application of velocity vector imaging in resynchronization therapy for patients with chronic heart failure

Objective To evaluate the effect of the velocity vector imaging （VVI） to quantify mechanical left ventricular asynchrony and to select patients for cardiac resynchronization therapy （CRT）. Methods The investigation included 17 patients, 15 male and 2 female, with refractory chronic heart failure and left ventricular asynchrony proven by VVI. All of them received biventricular synchronous pacing and the coronary sinus lead was inserted into the branch of coronary sinus which was adjacent to the delayed ventricular wall. All the patients were followed up at 1 month and 3 months. The maximal difference in delay （Ts max-rain） and the SD （Ts-SD） which were calculated from time to peak systolic velocity of 12 left ventricle （ LV ） segments by VVI were examined to evaluate the asynchrony in all the patients and follow up the effects after CRT. Results After biventricular synchronous pacing, the heart function was significantly improved. The LV ejection fraction was increased from 0.32 ±0.04 to 0.42 ±0.07 （ P 〈 0.01 ） and the 6-minute walk distance was increased from 309.77 ±76.05 m to 402.06 ±87.09 m （P 〈 0.01 ）. After 3 months follow up, the index of LV asynchrony were improved greatly. Conclusion VVI is a newer technique which can assess the LV asynehrony by Ts max-rain and Ts-SD, find the position of systolic delay and guide the electrode implantation.