Interhospital Transfer Improves Outcomes for Acute MI Patients

Patients hospitalized for acute MI have higher rates of coronary revascularization and lower long-term mortality if transferred to another, more specialized, institution, according to a study published online March 3, 2015, ahead of print in Heart. Take Home: Interhospital Transfer Improves Outcomes for Acute MI Patients

Researchers led by Isuru Ranasinghe, MBChB, MMed, PhD, of the Queen Elizabeth Hospital (Adelaide, Australia), looked at 40,482 patients hospitalized for acute MI at 161 centers in New South Wales, Australia, between July 1, 2004, and June 30, 2008. Interhospital transfer was recorded for 25% (n = 10,107).

Overall, transferred patients were younger and more likely to be male, have private health insurance, and have a diagnosis of STEMI. Compared with those who received care solely at the presenting hospital, transferred patients also had fewer cardiovascular risk factors, comorbidities, and acute complications at presentation. In addition, transferred patients were most likely to present at regional and remote hospitals and were moved primarily to centers in major cities (92.0%) with revascularization capabilities (94.3%).

Invasive cardiac procedures were performed in 57% of patients, with 34% (n = 13,805) of the total study population receiving PCI or CABG. In a propensity-score analysis of 8,427 matched pairs, transferred patients were 3 times more likely to receive a cardiac procedure and 4 times more likely to undergo in-hospital revascularization than those not transferred. Overall mortality was 26.6%, and transferred patients had lower mortality in hospital and at 30 days, 1 year, and over a median follow-up of 3.5 years (table 1).

Table 1. Propensity-Matched Revascularization and Mortality: Transfer vs Nontransfer 

Results were maintained in all subgroup analyses, including age above or below 65 years, STEMI vs NSTEMI diagnoses, and transfers originating from major city vs regional hospitals. The only exception was in patients transferred from revascularization-capable hospitals, who reaped no mortality benefit at 30 days or 1 year.

Sensitivity analyses showed the results are “robust and unlikely to be due to survival bias or to confounding by unmeasured variables,” the authors write.

Evidence-Based Treatments May Help Reduce Mortality

“Although transferred patients do have a lower baseline risk profile compared with nontransferred patients consistent with prior studies, our results show that most transferred patients have an absolute risk profile considered as intermediate-to-high risk when compared with clinical risk models,” Dr. Ranasinghe and colleagues observe. “This provides reassurance that patients who are transferred are likely to derive benefit from invasive therapy and other specialized care, given that intermediate-to-high risk patients are known to derive the greatest benefits from contemporary [acute] MI therapies.”

The lower mortality observed among transferred patients is “explained only partially by greater access to revascularization,” they note.

Other facets of care, including greater use of evidence-based treatments, are “likely to also contribute to the lower mortality among transferred patients,” the authors add. “These observations are important because improving medical care at acute hospitals without specialized cardiac services may improve outcomes for patients with an [acute] MI.”


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  • Ranasinghe I, Barzi F, Brieger D, Gallagher M. Long-term mortality following interhospital transfer for acute myocardial infarction. Heart. 2015;Epub ahead of print.

  • Dr. Ranasinghe reports receiving support from the National Health and Medical Research Council and the National Heart Foundation of Australia.