If a sequential saphenous vein graft occludes proximally but its distal part remains open, it may act as a large intercoronary collateral. In such situations percutaneous transluminal coronary angioplasty (PTCA) of a stenosis in one of the recipient native vessels may restore the function of the graft. In 250 of our patients who underwent PTCA after previous coronary artery bypass surgery, this technique could be used 20 times in 18 patients. PTCA was performed 3-101 months (mean 24.7 months) after bypass surgery. Complete revascularization could be achieved in all but three patients. Two patients had a small myocardial infarction during PTCA. The primary success rate was 95%. Two patients had a clinical and angiographic recurrence and underwent successful redilatation. Fourteen patients have remained symptom free during follow-up, which ranged from 4 to 44 months (mean 19.5 months). We conclude that this 'back-door technique' provides a new approach to symptomatic relief in patients with recurrent symptoms after previous sequential venous bypass grafting.