门控心肌显像对心脏起搏器植入早期左心室功能和结构的研究

目的 应用门控心肌显像观察心脏起搏器植入后早期患者左心室收缩功能与结构的变化.方法 患者27例,男9例,女18例,年龄(65.1±9.5)岁.其中起搏心室感知心室R波抑制型(VVI)起搏器组15例,起搏双腔感知双腔P波或R波抑制型(DDD)起搏器组12例.采用门控心肌显像方法测定患者起搏器植入前及植入后早期随访(4.6±1.5)个月]自身心律或起搏器工作状态下左心室功能参数值:左心室射血分数(LVEF),左心室舒张末容积(EDV),左心室收缩末容积(ESV)及左心室收缩时间.按左心室室壁活动靶心图将室壁活动度分为缺损、稀疏及正常3级.植入前后相比,有下列一项即为左心室功能重构:LVEF增加或降低10%及以上,室壁活动度改变1级及以上,左心室收缩时间延长或缩短1个时间段及以上;结构重构:EDV增加或降低10%以上.结果 (1)左心室功能重构:27例患者中,26例(96.3%;VVI组15例,DDD组11例)出现功能重构.26例中6例(23.1%;VVI组4例,DDD组2例)LVEF升高,8例(30.8%;VVI组4例,DDD组4例)LVEF降低,12例(46.2%;VVI组7例,DDD组5例)LVEF无变化.(2)结构重构:27例中13例(48.1%;VVI组10例,DDD组3例)出现结构重构.13例中4例(VVI组3例,DDD组1例)LVEF升高,3例(均为VVI组患者)LVEF降低,6例(VVI组4例,DDD组2例)LVEF无变化.结论 心脏起搏器植入后早期即可发生左心室功能重构,约半数患者出现左心室结构重构.心脏永久起搏器植入在患者心脏获得电生理学益处时,可能对左心室的功能和结构带来不利影响.

Gated cardiac SPECT in the assessment of the early functional and structural changes of left ventricle after pacemaker implantation

Objective The aim of this study was to assess the early functional and structural changes of left ventricle (LV) after pacemaker implantation by gated SPECT (GSPECT). Methods There were 27 patients male: 9, female: 18, age: (65.1±9.5) years] recruited into this study, 15 with VVI and 12 with DDD pacemaker. Functional parameters of LV, including ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV) and systolic time, under autologous rhythm or pacemake's rhythm were evaluated by the standard GSPECT procedure before and after (4.6±1.5) months pacemaker implantation. The Bull's-eye plot of left ventricular segmental motion was divided into 5 regions: apical, septal, lateral, inferior and anterior. A 3-point scoring system was used for severity measurement: 0=normal, 1=moderate decrease, 2=sever decrease. The functional remodeling was defined by one or more of the following criteria: more than 10% change in LVEF, more than 1 point change in wall motion score, systolic time delay or shortening. The structural remodeling was defined as more than 10% change in EDV after pacemaker implantation. Results Among 27 patients, there were 26 patients (15 with VVI pacemaker and 11 with DDD pacemaker) who showed LV functional remodeling and 13 (10 with VVI pacemaker and 3 with DDD pacemaker) showed LV structural remodeling. In autologous rhythm the LVEF did not change in 50% of patients after pacemaker implantation. Conclusion During the early period after the pacemaker implantation, functional remodeling of LV occurs in most patients and structural remodeling occurs in 50% of patients. About 50% of patients do not show any LVEF change. The results may suggest that besides the physiological benefits from the pacemaker implantation, other unfavorable functional and structural side-effects on LV must also be considered.