Preferential coronary arterial drug delivery

A transcatheter technique for administering drugs preferentially to the canine left coronary circulation is described. The method involves pulsed, diastolic, small-volume (0.2 ml) injections through a specially designed aortic cusp catheter. In order to evaluate preferential delivery to the coronary circulation, papaverine was administered using this technique and compared to intravenous delivery. Left circumflex and carotid arterial blood flow, as well as systemic arterial pressure, were simultaneously measured. In eight of ten animals studied, diastolic aortic cusp administration of the drug for periods of up to 30 minutes increased circumflex flow an average of 136%, increased carotid arterial flow 22%, and decreased systemic arterial pressure 18%. Intravenous delivery increased circumflex flow an average of 34%, increased carotid flow 41%, and decreased systemic arterial pressure 13%. The technique has immediate research and potential clinical application as a means of preferentially delivering diagnostic or therapeutic agents, such as thrombolytics, to the coronary circulation.