We assessed the effectiveness of distal hemoperfusion support during gradual, prolonged balloon inflation during percutaneous transluminal coronary angioplasty in high-risk patients. The patients were identified as having a poor left ventricular ejection fraction ( < 35%), > 50% of viable myocardium at risk percutaneous coronary balloon angioplasty, or both. A total of 64 procedures were performed in 61 patients. Angiographic success was achieved in 83 of 86 (96.5%) lesions treated with hemoperfusion support. Hospital complications included 1 patient who had a non-Q-wave infarction, 1 who had to undergo redo percutaneous coronary balloon angioplasty, and 5 who required coronary artery bypass operations. The hospital mortality was 7.8% (5 patients). This preliminary study indicates that hemoperfusion support can enable expeditious, simple, economical, and effective percutaneous transluminal coronary balloon angioplasty in a subset of labile patients in whom procedural failure frequently leads to sudden death.