Clinical and angiographic characteristics, procedural details and outcome were analyzed in 2,677 consecutive patients who underwent elective single-artery, single-lesion percutaneous transluminal coronary angioplasty (PTCA) between December 1980 and May 1987. Primary success was achieved in 2,479 (93%) patients. The primary success rate was significantly lower during the first period, when nonsteerable systems were used (73%), than in later periods (94%) (p less than 0.0001), when steerable and low-profile systems became available. Univariate analysis revealed the following variables as predictors of lower primary success: totally obstructed arteries (p less than 0.0001), presence of calcium in the narrowing (p = 0.002), prior myocardial infarction (p = 0.005), stenoses located in the right coronary artery (p = 0.02), narrowings between 90 and 99% in diameter (p = 0.02) and patients older than 60 years of age (p = 0.07). Multivariate analysis revealed the following 4 independent predictors of lower primary success: 100% obstruction (p less than 0.0001), calcium (p = 0.005), previous myocardial infarction (p = 0.029) and patients older than 60 years of age (p = 0.036). With present technology, single-narrowing elective PTCA can be performed with a high success rate in most patients. Although total occlusion, presence of calcium, older age and history of myocardial infarction influence the outcome unfavorably, PTCA can still be performed with acceptable primary success rates.