Background.In a highly competitive health care environment, even microgeographic differences in availability of tertiary services might affect access to care.Objectives.To study the impact of (1) geographic distance from patient's residence to cardiac revascularization services and (2) the availability of cardiac revascularization services at the hospital nearest the patient's residence on utilization of these services in a geographically small, densely populated area.Methods.Historical cohort study of 55,659 New Jersey residents hospitalized between 1992 and 1996 with primary diagnosis of acute myocardial infarction (AMI).Main Study Outcomes.Use of percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass graft surgery (CABG) within 90 days of initial hospitalization for AMI and in-hospital mortality. Distance from patient's residence to nearest hospital with cardiac revascularization services (PTCA and CABG) was a straight-line distance in miles, categorized as 0 to <2, 2 to <5, 5 to <10, 10 to <15, 15 to <20, 20 to <25, ≥25 miles. Adjusted odds of PTCA or CABG use at each distance category were compared with odds at ≥25 miles.Results.A strong linear decline in adjusted odds ratios for PTCA use was found with increasing distance of this service from the patient's residence (p<0.05). Adjusted odds of PTCA use were 2.4, 2.1, 1.8, 1.5, 1.3, and 1.0 times higher for each increasing distance category in comparison with ≥25 for patients aged <65 and 3.1, 2.7, 2.2, 1.9, 1.7, and 1.1 for patients aged ≥65. Use of CABG was also higher for patients residing closer to cardiac revascularization services. The availability of these services at the hospital nearest to the patient's residence also increased utilization. In-hospital mortality was not associated with distance from services.Conclusion.Even across a relatively small geographic area, shorter distance to services and availability of services at the nearest hospital were strongly related to increased utilization of cardiac revascularization services.