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.
ObjectiveTo investigate predictive value of intraoperative graft flow measurements during off-pump coronary artery bypass grafting (OPCAB) for early clinical prognosis. MethodsWe retrospectively analyzed the clinical data of 133 patients with three-vessel disease who underwent OPCAB in the Department of Cardiac Surgery of People's Hospital of Peking University in 2013 year. There were 103 males and 30 females with mean age of 62.84±7.13 years. Pulsatility index (PI) and mean flow were measured using a flow metre before the end of surgery. Then the total graft flow and the average graft flow were calculated. Univariate, bivariate correlation and logistic regression analysis were performed for statistical analysis. ResultsThe blood flow and PI of LIMA-to-LAD graft was respectively 28.69±16.90 ml/min and 2.70±1.39, and the total graft flow and the average graft flow was respectively 79.94±37.20 ml/min and 35.55±16.75 ml/min. The PI of LIMA-to-LAD graft was significantly correlated with serum cardiac troponin I(cTnI)level in 12 hours, with the highest serum cTnI level within 48 hours, with ICU stay and with ventilator time (P<0.01), but the correlation was not strong(coefficient correlation <0.4). Compared with the patients without perioperative myocardial infarction (PMI), the blood flow of LIMA-to-LAD graft, the total graft flow and the average graft flow were lower in the patients with PMI (P<0.01). Logistic regression analysis revealed that the total graft flow was an independent predictor of PMI (P=0.004, RR=0.950, 95%CI 0.918-0.984). ConclusionIntraoperative graft flow measurements during OPCAB can predict shortterm prognosis. The lower total graft flow is a risk factor for PMI.