Assistant Professor of Medicine, Clinical and Translational Science Institute, Tufts University School of Medicine
Dissertation Title: "Cost and Outcomes Analysis of Emergency Transport, Inter-Hospital Transfer and Hospital Expansion Policies in Cardiac Care"
Primary percutaneous coronary intervention (PCI) yields better clinical outcomes than thrombolytic therapy (TT) in the treatment of ST-segment elevation myocardial infarction (STEMI). TT is still widely used because most U.S. hospitals are not equipped to perform PCI. The first of three studies in this dissertation examines the impact on patient mortality and hospital volumes of Emergency Medical Services (EMS) strategies to increase delivery of patients with STEMI to PCI-capable hospitals. A second study investigates the clinical benefits and costs of hospital-based strategies to increase PCI capacity. A third study explores the association between the race, ethnicity and neighborhood of patients with STEMI and delay in EMS care. All three studies were based on a detailed geospatial model of Dallas County Texas EMS and hospital systems. Studies one and two drew patients from the Atlantic Cardiovascular Patient Outcomes Research Team (C-PORT) trial into a series of Monte-Carlo micro-simulations that tested EMS and hospital strategies for increasing the availability of PCI. Both studies employed a recently developed and validated predictive model to estimate the probability of 30-day mortality with PCI and with TT after STEMI. In the third study, we used 2004 administrative data from ten Dallas area municipal EMS systems to examine the relationship of patient race and neighborhood to time in EMS care. In the first two studies, we found that nearly all of the potential mortality benefit of PCI can be realized with policies that target the procedure to high-risk and high benefit patients. Policies that seek to make the procedure universally available confer little additional benefit at substantially higher costs and potentially adverse effects on EMS and hospital systems. In the third study, we found a statistically significant but not clinically meaningful difference in time to treatment among Asian Pacific Islanders in EMS care, compared to whites. This study did, however, demonstrate an unexpected and potentially harmful delay in EMS care among women compared to men. Efforts to expand the availability of PCI should be targeted to patients who can benefit most from the procedure. Calls for universal availability of PCI have become common in the cardiac care literature, and the case for this position is generally based on average patient outcomes as reported in clinical trials. This approach to PCI expansion masks important heterogeneity in the outcomes and experiences of patients with STEMI. Policy development that takes this heterogeneity in account can capture most of the benefits of universal PCI while minimizing adverse effects on costs and systems of care.