Intracoronary Heparin Delivery in Humans

Abstract

Background Inefficacy of systemic drug administration for restenosis prevention may partially relate to insufficient local drug concentration. This study aimed to evaluate the acute feasibility and long-term outcome of using an infusion-perfusion coil balloon, Dispatch. Methods and Results In 22 patients after balloon angioplasty, the coil balloon was studied for (1) feasibility of local heparin delivery, (2) symptoms and signs of ischemia during prolonged deployment compared with angioplasty balloon occlusion, (3) coronary pressure and flow distal to the inflated device, and (4) long-term clinical and angiographic results. During prolonged intracoronary deployment of the coil balloon (29±8 minutes), 5 of 22 patients developed mild chest pain versus 20 of 22 during angioplasty (275±283 seconds). Neither hemodynamic nor vectorcardiographic signs of ischemia were detected, in contrast to angioplasty balloon occlusion. Baseline flow across the coil balloon was 44±31 mL/min, increasing by a factor of 1.8±0.7 during pharmacologically induced hyperemia. A mean volume of 14.2±6.1 mL containing 1416±608 IU of heparin was infused locally at a pressure of 122±54 mm Hg. At 7±1-month follow-up, 1 asymptomatic patient had died, and of the remaining 21, 17 (81%) were asymptomatic. Angiographic follow-up was obtained in 15 of 21 patients (71%), including all 4 symptomatic patients. Mean minimal luminal diameter after the procedure was 2.16±0.49 mm and at follow-up, 1.89±0.45 mm, which corresponds to a restenosis rate (diameter stenosis ≥50%) of 7% (1/15). Conclusions Intracoronary use of the coil balloon after balloon angioplasty proved to be feasible and subjectively as well as objectively well tolerated during prolonged deployment by virtue of its perfusion properties. High volumes of heparin solution can be infused locally at very low pressure. No unfavorable clinical or angiographic long-term effects were observed.