The aim of this study was to determine the preferred treatment modality for calcified lesions in large (> or = 3 mm) coronary arteries, resulting in the largest lumen dimensions and the most favorable late clinical responses. Three hundred six lesions in 306 patients (223 men, mean age 66 +/- 11 years) were treated with either rotational atherectomy plus adjunct balloon angioplasty (n = 147), Palmaz-Schatz stents (n = 103), or a combination of rotational atherectomy plus adjunct Palmaz-Schatz stents (n = 56). The procedural success rate was 98.0% to 98.6% for each treatment modality. Minimal lumen diameter (MLD) before therapy was similar for all therapies. Final MLD after combination of rotational atherectomy plus Palmaz-Schatz stents was larger than after stent therapy or rotational atherectomy plus balloon angioplasty (3.21 +/- 0.49 mm, 2.88 +/- 0.51 mm, and 2.29 +/- 0.55 mm, respectively, p <0.0001). Correspondingly, final percent diameter stenosis was lowest after the combination of rotational atherectomy plus stent therapy, and significantly higher for stents or rotational atherectomy plus balloon angioplasty (4.2 +/- 15.3%, 14.1 +/- 13.3%, and 26.7% +/- 16.9%, respectively, p <0.0001). Event-free survival at 9 months was higher for patients treated with the combination of rotational atherectomy plus stents than either stent therapy or rotational atherectomy alone (85%, 77%, and 67%, respectively, log-rank p = 0.0633). The only significant independent predictor of an event during the 9-month follow-up period was the MLD after intervention (odds ratio 0.495, 95% confidence interval 0.308 to 0.796, p = 0.0037). We conclude that preatheroablation using rotational atherectomy, followed by adjunct stent placement for calcified lesions in large arteries, is associated with infrequent complications, the largest acute angiographic results, and the most favorable late clinical event rates.