瞬时流量测定技术在冠状动脉旁路移植术中的应用及其相关因素分析

The Application of the Intraoperative Transit Time Flow Meter in Coronary Artery Bypass Grafting and Correlative Analysis

目的评估瞬时流量测定(transit time flow meter,TTFM)技术在冠状动脉旁路移植术(CABG)中探查移植血管血流通畅状态的应用价值,并分析其测定结果的相关因素。方法对我科2002年3月至2004年1月连续行CABG 301例患者的791支血管移植物进行TTFM测定,按照入选标准从中筛选出左乳内动脉(LIMA)旁路移植到左前降支(LAD)的165例患者的TTFM结果,进行血流量和搏动指数(pulsatility index,PI)的多因素分析。结果TTFM技术提示,791支移植物中有严重质量问题的移植血管5支,均手术证实并加以改正。可能影响移植物血流量的主要因素为LAD远端直径、LIMA直径、心肌梗死位置、LAD近端狭窄程度、反流量百分比(percentage of insufficiency)、左心室舒张期末内径、手术方式(体外循环和非体外循环);影响PI值的主要因素为LAD远端直径、反流量百分比和手术方式。结论TTFM在判断CABG移植物状态时具有一定的诊断价值。多种因素均可影响移植物的血流量和PI值,应考虑主要影响因素以及临床表现来提高TTFM诊断技术错误的敏感性。

Objective To evaluate the applicating value of transit time flow meter（TTFM） in determing the status of coronary grafting and analyze the correlation factors of the measuring results. Methods Three hundred and one patients underwent CAB（3 in this hospital from March 2002 to January 2004. Seven hundred and ninety-one grafts were measured with TTFM. One hundred and sixty-five patients whose left internal mammary artery （LIMA） were grafted to left anterior descending branch （LAD） were included in this retrospective study according to inclusion criteria, the graft flow and pulsatility index（P1） as dependent and the other 17 factors as independent factors which were analyzed by muhilinear regression analysis. Results According to TTFM technique, technical errors of 5 grafts had been detected and corrected intraoperatively among 791 grafts. The graft flow of LIMA-LAD related strictly to LAD distal diameter, LIMA diameter, anterior myocardial infraction, stenosis degree of proximal LAD, percentage of insufficiency （% insufficiency）, left ventricle end-diastole diameter and different surgical technique （on- pump, off-pump）. PI was influenced by LAD distal diameter, different surgical technique （on-pump, off-pump） and %insufficiency. Conclusions Evaluation of TTFM is valuable in determining the status of a coronary graft after CAB（3. Multiple factors could influence the grafts flow and the PI. The intraoperative technical control of anastomoses should be considered together with major influential factors and cardiac performances.