Care Transitions after Acute Myocardial Infarction for Transferred-In Versus Direct-Arrival Patients

Background-Many patients in the United States require transfer from one hospital to another for acute myocardial infarction (MI) care. How well these transferred-in patients are transitioned back to their local community is unknown. Methods and Results-We used linked Medicare claims data to examine postdischarge outcomes of 39 136 patients with acute MI aged ≥65 years discharged alive from 451 US hospitals in Acute Coronary Treatment and Intervention Outcomes Network Registry-Get With the Guidelines. Multivariable Cox modeling was used to compare the likelihood of outpatient clinic follow-up and risks of all-cause mortality and all-cause or cardiovascular readmission at 30 days post MI between transferred-in and direct-arrival patients. From 2007 to 2010, 14 060 of 39 136 patients (36%) required interhospital transfer for acute MI care, traveling a median of 43 miles (interquartile range, 27-68 miles; 77.6 km [interquartile range, 48.2-122.6 km]). Compared with those arriving directly, transferred-in patients with MI were slightly younger (median age, 73 versus 74; P<0.01) but less likely to have previous MI, heart failure, and previous revascularization than direct-arrival patients. Relative to direct-arrival patients, those transferred-in had a lower likelihood of outpatient follow-up within 30 days post discharge (risk-adjusted incidence, 69.9% versus 78.2%; hazard ratio [HR], 0.90; 95% confidence interval, 0.87-0.92) and higher adjusted 30-day all-cause and cardiovascular readmission risks (14.5% versus 14.0%; HR^all-cause, 1.08; 95% confidence interval, 1.01-1.15 and 9.5% versus 9.1%; HR^{cardiovascular}, 1.13; 95% confidence interval, 1.04-1.22). In contrast, risk-adjusted 30-day mortality was similar between transferred-in and direct arrivals (1.6% versus 1.6%; HR, 1.05; 95% confidence interval, 0.86-1.27). Conclusions-Transferred-in patients with acute MI are less likely to have outpatient clinic follow-up within 30 days and more likely to be readmitted within the first 30 days post discharge compared with direct-arrival patients. These results indicate room for improvement in the safe and seamless transition of care for transferred patients with MI traveling back to their home environments.