Effect of rate of administration of recombinant tissue plasminogen activator on efficacy of coronary thrombolysis.

The authors employed a canine model of coronary thrombosis, induced by injection of radioactive blood clot, via a catheter placed in the left anterior descending (LAD) coronary artery, to compare effects of different rates of administration of recombinant tissue plasminogen activator (rtPA) on efficacy of coronary thrombolysis. In one group of dogs 0.75 mg/kg of rtPA was administered via the catheter placed in the LAD coronary artery over fifteen minutes. In a second group of dogs the same dose of rtPA was administered over forty-five minutes. Compared with the group in which the drug was administered over forty-five minutes, by thirty and forty-five minutes after onset of treatment, the extent of coronary thrombolysis was significantly greater (P < 0.05) in the group who received the drug over fifteen minutes. These results demonstrate that the rate of intracoronary administration of rtPA may significantly affect thrombolytic efficacy.