Intracoronary shunt prevents left ventricular function impairment during beating heart coronary revascularization

Objective: Beating heart coronary revascularization is becoming increasingl y popular world-wide. Temporary occlusion of the coronary artery is often r equired in order to perform the anastomosis. An alternative method to maint ain perfusion is to use an intracoronary shunt. In this study, we monitored global left ventricular function and regional wall motion in the presence or absence of a shunt using transesophageal echocardiography (TEE). Method: Left ventricular wall motion score index (WMSI), wall motion score (WMS) i n the left anterior descending (LAD) coronary artery territory, and ejectio n fraction (EF%) were measured by multiplane TEE during construction of the left internal mammary artery (LIMA)-LAD coronary artery anastomosis in 40 patients undergoing revascularization with or without the use of a shunt. W MSI was assessed preoperatively, 1, 3 and 6 min during the construction of the anastomosis and after 5 min of reperfusion. WMS was assessed at 6 min d uring anastomosis and after 5 min of reperfusion. EF% was calculated preope ratively, 5 min into the construction of the anastomosis, and 5 min after r eperfusion. Results: During construction of the anastomosis, when the shunt was used, there were no changes in WMSI, WMS in the LAD territory or EF%. A significant decline in these parameters was seen in the group in which th e shunt was not used, although on reperfusion all the values returned to ba seline control. Conclusion: (i) occlusion of the LAD to perform the anastom osis results in temporary impairment in left ventricular function with comp lete recovery on reperfusion; (ii) the use of an intracoronary shunt presum ably by maintaining myocardial perfusion prevents deterioration in ventricu lar function; (iii) from this data it seems therefore advisable to use an i ntracoronary shunt in patients with unstable angina, poor left ventricular function, or in cases in which a longer time to perform the anastomosis is anticipated. (C) 1999 Elsevier Science B.V. All rights reserved.