Background-Improving patients’quality of life is a primary indication for percutaneous coronary intervention(PCI), yet little is known about patient characteristics associated with greater quality-of-life improvement from the procedure. This study was conducted to identify patient characteristics associated with quality-of-life benefit after PCI. Methods and Results-A consecutive series of 1518 patients undergoing PCI in nonacute myocardial infarction settings were prospectively enrolled into an observational study documenting their postprocedural health status. We examined univariate and multivariable associations between baseline patient characteristics and quality of life 1 year after the procedure using the disease-specific Seattle Angina Questionnaire(SAQ)to quantify the impact of patients’coronary disease on their quality of life. Baseline angina frequency and physical function were the strongest predictors of quality-of-life improvement 1 year after PCI. In comparing patients without angina to those experiencing monthly, weekly, and daily angina, the quality-of-life improvements(mean±SEM)were 21.4±2.1, 30.7±2.2, and 34.6±2.6 points greater(P< 0.001). Patients with mild, moderate, and severe physical limitation improved 13.8±1.9, 20.0±2.1, and 13.5±3.5 points more than those with minimal baseline physical limitation(P< 0.001). These findings were maintained in multivariable models correcting for baseline differences in demographic, clinical, disease-severity, and health-status variables. Conclusions-Preprocedural angina frequency is the most important prognostic indicator of quality-of-life improvement after PCI. Although substantial quality-of-life benefits are attained in most patients with preprocedural angina, more careful consideration of the potential benefits and risks of the procedure are needed in asymptomatic patients. Background-Improving patients’ quality of life is a primary indication for percutaneous coronary intervention (PCI), yet little known known about patient characteristics associated with greater quality-of-life improvement from the procedure. This study was conducted to identify patient characteristics associated with quality-of-life benefit after PCI. Methods and Results-A consecutive series of 1518 patients undergoing PCI in nonacute myocardial infarction settings were prospectively enrolled into an observational study documenting their postprocedural health status. We examined univariate and multivariable associations between baseline patient characteristics and quality of life 1 year after the procedure using the disease-specific Seattle Angina Questionnaire (SAQ) to quantify the impact of patients’coronary disease on their quality of life. Baseline angina frequency and physical function were the strongest predictors of quality-of-life improvement 1 year after PCI. In comparing patients wi thout angina to those experiencing monthly, weekly, and daily angina, the quality-of-life improvements (mean ± SEM) were 21.4 ± 2.1, 30.7 ± 2.2, and 34.6 ± 2.6 points greater (P <0.001) moderate, and severe physical limitation improved 13.8 ± 1.9, 20.0 ± 2.1, and 13.5 ± 3.5 points more with those with minimal baseline physical limitation (P <0.001). These findings were maintained in multivariable models correcting for baseline differences in demographic, clinical, disease-severity, and health-status variables. Conclusions-Preprocedural angina frequency is the most important prognostic indicator of quality-of-life improvement after PCI. Although substantial-of-life benefits are attained in most patients with preprocedural angina, more careful consideration of the potential benefits and risks of the procedure are needed in asymptomatic patients.