Patients ≥ 80 years old with coronary artery disease constitute a particular risk group in relation to percutaneous coronary intervention (PCI). From 2002 through 2008 we examined the annual proportion of patients ≥ 80 years old undergoing PCI in western Denmark, their indications for PCI, and prognosis. From 2002 through 2009 all elderly patients treated with PCI were identified in a population of 3.0 million based on the Western Denmark Heart Registry. Cox regression analysis was used to compare mortality rates according to clinical indications controlling for potential confounding. In total 3,792 elderly patients (≥ 80 years old) were treated with PCI and the annual proportion increased from 224 (5.4%) in 2002 to 588 (10.2%) in 2009. The clinical indication was stable angina pectoris (SAP) in 30.2%, ST-segment elevation myocardial infarction (STEMI) in 35.0%, UAP/non-STEMI in 29.7%, and "ventricular arrhythmia or congestive heart failure" in 5.1%. Overall 30-day and 1-year mortality rates were 9.2% and 18.1%, respectively. Compared to patients with SAP the adjusted 1-year mortality risk was significantly higher for patients presenting with STEMI (hazard ratio 3.86, 95% confidence interval 3.08 to 4.85), UAP/non-STEMI (hazard ratio 1.95, 95% confidence interval 1.53 to 2.50), and ventricular arrhythmia or congestive heart failure (hazard ratio 2.75, 95% confidence interval 1.92 to 3.92). In patients with SAP target vessel revascularization decreased from 7.1% in 2002 to 2.5% in 2008. In conclusion, the proportion of patients ≥ 80 years old treated with PCI increased significantly over an 8-year period. Patients with SAP had the lowest mortality rates and rates of clinically driven target vessel revascularization decreased over time.