Pulsed-spray thrombolysis is accomplished through forceful injection of a spray of highly concentrated urokinase into clot by using catheters with multiple side holes. We previously reported the immediate technical efficacy of the method in eight arterial and 10 bypass graft occlusions. We now describe the clinical efficacy of the method in a second, larger series of 23 native artery occlusions and 25 bypass graft occlusions. Transluminal angioplasty was performed after thrombolysis in 21 of the arteries and 24 of the bypass grafts. Initial thrombolysis was observed in all artery occlusions and all but one bypass graft occlusion with an average time for pulsed-spray lysis of 65 +/- 28 min in native arteries and 93 +/- 38 min in bypass grafts. Recanalization with improvement in symptoms or distal pulses after thrombolysis and angioplasty was achieved in 74% of treated arterial occlusions and 92% of treated graft occlusions. Of the 15 arteries that were recanalized and did not require adjunctive surgery, seven remained patent at 3-28 months follow-up. Nine of 23 recanalized bypass grafts required early adjunctive surgery. Of the nine synthetic and five saphenous vein grafts successfully recanalized and not requiring surgical revision, the mean patency was 4.3 +/- 3.1 months and 3.0 +/- 2.2 months, respectively. Minor complications were seen in 23% of cases. The two major complications (4%) involved one groin hematoma requiring surgery and one episode of gastrointestinal hemorrhage. We conclude that combined pulsed-spray thrombolysis and angioplasty achieve rapid and consistent arterial and graft recanalization with minimal risk. The method offers a favorable alternative to standard thrombolytic therapy of arterial occlusions. In occluded synthetic and vein bypass grafts, the technique is sometimes beneficial, either alone or combined with surgical revision.