Volume-outcome relation for physicians and hospitals performing angioplasty for acute myocardial infarction in New York state.

An inverse relation exists between the number of coronary angioplasty procedures performed by physicians or hospitals and short-term mortality. It is not known, however, whether a similar relation holds for physicians and hospitals that perform primary angioplasty for acute myocardial infarction. We analyzed data from the 1995 New York State Coronary Angioplasty Reporting System Registry to determine the relation between the number of primary angioplasty procedures performed by physicians and hospitals and in-hospital mortality. Patients who underwent angioplasty procedures within 23 hours of onset of acute myocardial infarction without preceding thrombolytic therapy were included (n=1342). In-hospital mortality was reduced 57% among patients who underwent primary angioplasty by high-volume as opposed to low-volume physicians (adjusted relative risk 0.43; 95% CI 0.21 to 0.83). When patients with acute myocardial infarction were treated with primary angioplasty in high-volume hospitals rather than low-volume institutions, the relative risk reduction for in-hospital mortality was 44% (adjusted relative risk 0.56; 95% CI 0.29 to 1.1). Compared with patients treated at low-volume hospitals by low-volume physicians, patients treated at high-volume hospitals by high-volume physicians had a 49% reduction in the risk of in-hospital mortality (adjusted relative risk 0.51; 95% CI 0.26 to 0.99). Among hospitals in New York State, a higher volume of primary angioplasty procedures performed by physicians and/or hospitals was associated with a lower mortality rate.