Assessment of the left thoracic artery graft late postoperative patency by ultrasound contrast with angiography

Abstract

Objective To access the left internal thoracic artery (LITA) graft late postoperative patency after coronary artery bypass grafting (CABG) by peripheral blood vessel ultrasound combined with color Doppler coronary flow imaging (CDCFI).In contrast with angiography,try to find available flow parameter to access graft patency.Methods Forty-six patients with CABG more than 1 year postoperatively followed-by angiography were detected by ultrasound.The LITA graft and left anterior descending artery were examined.Systolic and diastolic peak velocity(Smax,Dmax),velocity time integral(VTIs,VTId)of each segment were measured separately.The ratio of diastolic and systolic peak velocity (D/S),and diastolic velocity time integral fraction(DVTIF) were calculated.All patients were divided into groups according to angiography results.Results Thirty -one LITA grafts were patent,11 were dysfunctional,4 were occlusive.According to the angiography results,the flow parameters of the proximal segment of LITA graft were significant.The D/S and DVTIF of patent group was higher than that of dysfunctional group.The diastolic peak velocity of distal segment of LAD of patent group was higher than that of dysfunctional group.Conclusions Peripheral blood vessel ultrasound combined with CDCFI could provide the evidence to access the patency of the graft.It was an effective method for the clinical follow-up. Key words: Echocardiography; Internal mammary coronary artery anastomosis; Internal thoracic artery; Color Doppler coronary flow imaging; Coronary angiography