Transit Time Flowmetry in Coronary Artery Bypass Grafting-experience at Queen Alia Heart Institute, Jordan.

OBJECTIVES To assess the results of transit time flowmetry (TTF) on a consecutive group of coronary artery bypass grafting (CABG) patients at Queen Alia Heart Institute. METHODS Intraoperative flow measurements of a consecutive group of 436 CABG patients. The flow pattern for each coronary artery system was assessed including mean flows, pulsatility index (PI) and the need for revision. RESULTS A total of 1394 grafts in 436 patients were assessed (3.2 grafts per patient), wherein 100 grafts showed inadequate flowmetry results (7.2%); most of which were in the circumflex and right coronary artery systems with a percentage of 9.4% and the least in the LAD system with a percentage of 4.4%. The mean flow of grafts to the LAD system was 33.4±5.3 mL/min with a PI of 2.4±0.4; while the mean for grafts to the circumflex artery system was 35.1±7.2 mL/min with a PI of 3.5±0.7. The mean for the right coronary artery was 38.4±5.9 mL/min with a PI of 2.6±0.6. Revisions occurred in five patients (1.1%). Suboptimal grafts to the LAD system exhibited a flow of 14.1±7.4 mL/min with a PI of 6.9±1.7. While for the circumflex system a flow of 5.5±3.6 mL/min was reported with a PI of 10.4±7.8; and for the right coronary system a flow of 7.2±5.3 mL/min with a PI of 9.1±5.7 was reported. CONCLUSION Grafts to the LAD system showed the best flowmetry results compared to grafts to the circumflex and right coronary systems. A proportion of poor grafts were revised.