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

We sought to test the effectiveness of ultra-short-acting cardioselective beta-blockade, landiolol hydrochloride, for warm heart surgery.

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.

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.

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.