Experimental ischemic heart disease induced by thromboxane A2 in rabbits

How an acute ischemic attack is induced in a patient with coronary atherosclerosis is unknown and we carried out studies using thromboxane A2 (TXA2) to determine if acute myocardial ischemia and necrosis could be induced in rabbits. TXA2 was perfused through the coronary artery for 5 seconds by means of a Swan-Ganz catheter through the right common carotid artery. Significant serial changes of ST-T on ECG and hypotension were observed from 1 minute to more than 1 day after the perfusion in all 22 rabbits. The TXA2 that was composed of both aggregated platelets and prostaglandin H2 induced the same response, and such was dose dependent. The inactivated TXA2 was without effect. Seventeen of the experimental rabbits were autopsied. Histological studies of the hearts showed focal myocardial ischemia and necrosis in all rabbits except one autopsided 10 minutes after the perfusion. TXA2 is apparently capable of inducing acute myocardial ischemia and necrosis.