BACKGROUND: Abrupt or threatened closure is the major acute complication following conventional coronary angioplasty with a persistent incidence of 2% to 10%. OBJECTIVES: In order to evaluate the safety and efficacy of endoluminal stenting and autoperfusion balloon angioplasty in the setting of abrupt or threatened closure following coronary angioplasty, the short- and long-term clinical and angiographic follow-up of respectively 45 and 51 patients treated by either method were compared. METHODS: From August 1986 through August 1992, consecutive patients treated by either endoluminal stenting or autoperfusion balloon angioplasty for abrupt closure following coronary angioplasty, were entered into an observational trial that requested clinical follow-up and repeat angiography at 6 months. RESULTS: Except for vessel localization, baseline clinical, angiographic and procedural characteristics were comparable. The in-hospital clinical and angiographic outcome was similar (p = 0.85) with 69% event-free patients in both treatment groups. The postprocedural minimal luminal diameter was larger following stenting: 2.67 +/- 0.76mm versus 2.07 +/- 0.70mm (autoperfusion balloon) (p = 0.0002). At follow-up, there were less events in the stent group: 11% versus 34% for the autoperfusion balloon angioplasty group, (p = 0.03). Restenosis rates were 5% (2/37 patients, stent) versus 27% (11/41 patients, autoperfusion balloon) (p = 0.02). CONCLUSIONS: Autoperfusion balloon angioplasty and endoluminal stenting are effective and safe therapeutic options for abrupt or threatened closure following coronary angioplasty with a comparable short-term clinical and angiographic outcome. However, during follow-up, more complications occur following autoperfusion balloon angioplasty. This is explained by a higher restenosis rate in this treatment group.