Levosimendan’s effect on coronary artery grafts blood flow in patients with left ventricular dysfunction, assessment by transit time flow meter

AbstractObjectivesLevosimendan improves the function of stunned myocardium and cardiac performance in heart failure without significantly increasing myocardial oxygen consumption. We evaluated the effects of levosimendan on hemodynamics and coronary grafts blood flow (CBF) in patients with left ventricular dysfunction undergoing pump coronary artery bypass grafts (CABG) surgery using transit time flow meter (TTFM).MethodsTwenty patients with stable angina and left ventricular ejection fraction 30–50% scheduled for elective CABG surgery were randomized to receive levosimendan (0.1mg/kg/min) or placebo, started immediately after induction of anesthesia and continued for 24h in ICU. Coronary bypass grafts flow was measured 30min after termination of cardiopulmonary bypass (CPB). Flow curve pattern, mean graft flow, and pulsatile index (PI) were measured and analyzed. Hemodynamics was collected serially at five time points.ResultsMean flow in all grafts was significantly higher in the Levosimendan group in comparison to control group (p<0.05). When we compared mean flow between different types of grafts in Levosimendan group, we found that venous sequential grafts had higher flow than non-sequential graft (p<0.001) and arterial grafts (p=0.005). Also saphenous vein grafts (SVG) had higher flow in comparison to left internal mammary artery (LIMA) grafts (p=0.004). As regard PI, it was also more significant in the Levosimendan group for all grafts (p