Use of mechanical devices for distal hemoperfusion during balloon catheter coronary angioplasty

Abstract
Previous attempts to protect the dependent myocardium during balloon catheter coronary angioplasty in animals and humans have had generally unsatisfactory results. This paper summarizes the authors' experience in investigating commercially available mechanical pumps for distal coronary hemoperfusion during balloon angioplasty. Both roller and piston pumps can attain adequate distal perfusion without significant side effects in the majority of patients. Our goal was to suppress angina for at least 5 min to prolong balloon inflation in awake patients. Minor T-wave changes without concomitant angina pectoris can be expected when the distal coronary bed is perfused with hypothermic blood. Side branch occlusion by the inflated balloon prevents effective protection of the corresponding part of the dependent myocardium during distal hemoperfusion, which may result in persistent angina and ST-T changes uncorrected by increasing the hemoperfusion rate. Distal coronary diffuse spasm, rare and transient, was the only immediate complication of this procedure. It is suggested that intense local wall stimulation could occur with a higher flow rate (jet effect). Improved balloon catheter pressure/flow characteristics and on-line continuous mechanical pumps should soon make distal coronary hemoperfusion through balloon catheters an accepted clinical technique.