• Interventional Techniques & Devices
• Myocardial Infarction Clinical Trials

According to a new analysis of data from the Massachusetts Data Analysis Center (MASS-DAC) registry, patients who are undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) face similar risks of death and MI but higher rates of repeat revascularization when treated at hospitals without on-site cardiac surgery (non-SOS) capabilities compared with hospitals with cardiac surgery capabilities (SOS).

If it can be performed quickly (within 90 minutes of initial medical contact), primary PCI is the preferred method of reperfusion in patients with STEMI, according to current American Heart Association/American College of Cardiology guidelines. However, most patients with STEMI present to hospitals without SOS, where primary PCI is generally discouraged (eg, in Massachusetts). With limited access to immediate PCI, many patients with STEMI either are treated with fibrinolytic therapy or face potential delays in treatment in transfer to PCI centers.

Allowing primary PCI in hospitals without SOS could greatly expand access to timely PCI for STEMI patients. In 1997, the Massachusetts Department of Health initiated a pilot program for primary PCI at non-SOS hospitals. Ather Anis, MD, Boston University Medical Center, Boston, MA, presented findings from the MASS-DAC analysis, comparing outcomes of primary PCI in hospitals depending on the availability of SOS.

Of a total of 6139 patients in the MASS-DAC registry with STEMI who underwent PCI between 2005 and 2007, there were 3018 patients with complete data who were not transferred and were treated at centers with (n=2041) and without (n=977) cardiac surgery capabilities. Demographic, clinical, and angiographic variables were included in multivariate analyses, with propensity score-matching to minimize confounding. The primary outcomes were 30-day and 1-year all-cause mortality, MI, repeat revascularization, and target vessel revascularization.

Patients who were treated at non-SOS hospitals were more frequently white, covered by HMO insurance, and had multivessel disease. All-cause mortality was similar in centers with and without cardiac surgery capabilities at 30 days (4.5% vs 5.7%; p=0.22) and at 1 year (9.4% vs 8.6%; p=0.51). Although there was a trend toward increased risk of MI at 30 days at non-SOS hospitals (4.35% vs 2.82%; p=0.05), the risk of MI was similar at 1 year (6.7% vs 5.1%; p=0.11).

Target vessel revascularization rates were also similar at 30 days (6.3% vs 5.0%; p=0.21) and at 1 year (10.9% vs 9.7%; p=0.39). However, repeat revascularization rates were significantly higher in non-SOS centers through 30 days (14.9% vs 7.6%; p<0.0001) and 1 year (21.0% vs 14.7%; p<0.0001).

This observational analysis suggests that primary PCI may be safely performed in patients who present with STEMI to non-SOS hospitals, with no differences observed in 30-day or 1-year mortality. Dr. Anis noted, however, that “STEMI patients undergoing primary PCI at hospitals without on-site cardiac surgery had a slightly higher incidence of recurrence [MI] at 30 days for reasons that are unclear and will require further study.” Further analyses that account for differences in the timing of procedures and selection of patients who underwent PCI and other differences in patients between hospital types are pending.

• © 2009 MD Conference Express