Ultra-short-acting cardioselective beta-blockade attenuates postischemic cardiac dysfunction in the isolated rat heart

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 degreesC) 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 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. (C) 2001 Elsevier Science B.V. All rights reserved.