The effect of two different diltiazem treatments on infarct size in ischemic, reperfused porcine hearts.

Abstract

IT IS well accepted that the speed at which ischemic myocytes die depends on the extent of the imbalance between oxygen supply and demand. 2Accordingly, a number of agents have been found that delay the development of infarcts by reducing myocardial oxygen consumption during ischemia.3 Among them are calcium antagonists, a heterogeneous group of compounds that can improve the myocardial oxygen supply-demand balance by depressing myocardial contractility, decreasing heart rate, and inducing coronary vasodilation. A beneficial effect of calcium antagonists on ischemic cellular injury has been demonstrated in a variety of different preparations,5-1 although in some studies this favorable influence has not been observed.'2'13 Since the basic action of calcium antagonists is not only an inhibition of the slow channel in myocytes and pacemaker cells but also in all types of smooth muscle cells (which results in a systemic and coronary vasodilation'4), it is difficult to distinguish in intact animals the beneficial effect that is due to an obviously improved oxygen supply-demand ratio (e.g.,

Transient Occlusion of the Left Anterior Descending Coronary Artery in Pigs

“…Coronary artery circulation in pigs presents regional distribution similar to hu mans and a negligible native collateral net work, in contrast with other laboratory ani mals [5][6][7]9], Therefore, the pig is an inter esting model for the study of myocardial effects after transient coronary occlusion (CO) [4,12,14] in many clinical circumstanccs in which coronary collateral network is poorly developed.…”

Prolonged protective effect of the calcium antagonist anipamil on the ischemic reperfused rabbit myocardium: Comparison with verapamil

“…anipamil, verapamil, calcium antagonist, ischemia, reperfusion, cardioprotection Roberto Ferrari, Riccardo Raddino, Claudio Ceconi, Salvatore Curello, Salvatore Ghielmi, Odoardo Visioli Cattedra di Cardiologia e Cattedra di Chimica, Universita degli Studi di Brescia, Brescia, Italy utilization and decreasing ATP production [2]. These considerations have stimulated, during the last few years, a growing interest in the possibility of reducing ischemic injury with agents commonly referred to as calcium antagonists [3][4][5]. …”

Cardioprotective Effect of Metipranolol on Ischemic Heart Muscle

“…Klein et al [9] observed a similar cardio protective effect on the metabolic situation of the ischemic myocardium in pigs after administration of diltiazem (Ca2+ antago nist). Besides improvement of metabolic pa rameters (increased concentration of ADP and NAD in the myocardium) the authors described diminution of the infarct size of the heart.…”