T Yasuda1, H Kamiya, Y Tanaka, G Watanabe. 1. Department of Surgery (I), Kanazawa University School of Medicine, Takaramachi 13-1, 920-8641, Kanazawa, Japan. yasuda@nyc.odn.ne.jp
Abstract
OBJECTIVES: We sought to test the effectiveness of ultra-short-acting cardioselective beta-blockade, landiolol hydrochloride, for warm heart surgery. METHODS: The isolated perfused rat heart preparation was used. After preischemic measurement of cardiac function, 3 min of coronary infusion of crystalloid cardioplegic solution (37 degrees C) with landiolol hydrochloride of various concentrations (1, 2.5, 5, and 10 mmol/l) or without it (control group) was performed, followed by 30 min of warm ischemic arrest. Finally, postischemic function was measured. RESULTS: The percentage recoveries of heart rate in hearts receiving 0, 1, 2.5, 5, and 10 mmol/l landiolol hydrochloride were 89.4+/-3.4%, 90.9+/-1.7%, 89.6+/-1.8%, 83.4+/-3.3%, and 74.3+/-1.9% (P<0.05 vs. 0, 1, and 2.5 mmol/l groups), respectively. The percentage recoveries of aortic flow were 55.6+/-3.1%, 62.8+/-3.3%, 75.0+/-4.2% (P<0.05 vs. 0 and 10 mmol/l groups), 65.3+/-5.3%, and 51.6+/-4.0%, respectively. Similar recovery profiles were observed with the first derivative of the rise in aortic pressure, stroke volume and stroke work. The total amount of coronary effluent in the hearts receiving 5 or 10 mmol/l was lower than in the other groups. CONCLUSIONS: Landiolol hydrochloride has the potential to enhance postischemic cardiac function after the warm cardioplegic arrest. The optimal concentration for maximum postischemic functional recovery was 2.5 mmol/l, and recoveries of aortic flow and heart rate decreased in hearts receiving 5 mmol/l or more.
OBJECTIVES: We sought to test the effectiveness of ultra-short-acting cardioselective beta-blockade, landiolol hydrochloride, for warm heart surgery. METHODS: The isolated perfused rat heart preparation was used. After preischemic measurement of cardiac function, 3 min of coronary infusion of crystalloid cardioplegic solution (37 degrees C) with landiolol hydrochloride of various concentrations (1, 2.5, 5, and 10 mmol/l) or without it (control group) was performed, followed by 30 min of warm ischemic arrest. Finally, postischemic function was measured. RESULTS: The percentage recoveries of heart rate in hearts receiving 0, 1, 2.5, 5, and 10 mmol/l landiolol hydrochloride were 89.4+/-3.4%, 90.9+/-1.7%, 89.6+/-1.8%, 83.4+/-3.3%, and 74.3+/-1.9% (P<0.05 vs. 0, 1, and 2.5 mmol/l groups), respectively. The percentage recoveries of aortic flow were 55.6+/-3.1%, 62.8+/-3.3%, 75.0+/-4.2% (P<0.05 vs. 0 and 10 mmol/l groups), 65.3+/-5.3%, and 51.6+/-4.0%, respectively. Similar recovery profiles were observed with the first derivative of the rise in aortic pressure, stroke volume and stroke work. The total amount of coronary effluent in the hearts receiving 5 or 10 mmol/l was lower than in the other groups. CONCLUSIONS:Landiolol hydrochloride has the potential to enhance postischemic cardiac function after the warm cardioplegic arrest. The optimal concentration for maximum postischemic functional recovery was 2.5 mmol/l, and recoveries of aortic flow and heart rate decreased in hearts receiving 5 mmol/l or more.