Coronary artery stent outcomes in a Medicare population: less emergency bypass surgery and lower mortality rates in patients with stents.

Background: Randomized trials of coronary stents versus conventional balloon angioplasty have demonstrated improved short- and long-term outcomes for selected patients receiving stents. The purpose of this study was to compare outcomes in patients receiving stents with those undergoing conventional balloon angioplasty in everyday clinical practice.
Methods and Results: This study uses information from the Medicare Provider Analysis and Review files for fiscal years 1994 and 1996, the first year the coronary stent code was used. For patients 65 years of age and older, 165,657 cases in 1994 and 201,869 in 1996, including 74,836 cases with stent placement, were identified. Outcomes included hospital deaths, use of same- admission coronary artery bypass surgery, and either or both. Analyses were performed separately for those with and those without a principal diagnosis of acute myocardial infarction. Hospital mortality rates were similar in both years, but the use of same-admission coronary artery bypass surgery was lower in 1996. In that year, for both patients with and those without acute myocardial infarction, hospital death and the use of same-admission coronary artery bypass surgery were lower in the stent group. Additionally, results in the stent group were generally better at high-volume (>200 cases per year) institutions, as was the case for the prestent, 1994 results.
Conclusions: This study documents improved short-term outcomes in older patients who undergo coronary stent placement. Stenting did not eliminate the finding of improved outcomes at high-volume centers.