Heart attack patients in the U.S. are more likely to be readmitted to the hospital within 30 days of surgery than patients in Canada, Australia and several other European countries, a new study revealed.

The research, published in the Journal of the American Medical Association, analyzed data from more than 5700 patients in more than 15 countries. Duke researchers found that 14 percent of American patients who experienced a ST segment elevation myocardial infarction (a severe type of heart attack that occurs when a coronary artery becomes at least partially blocked by a blood clot) were readmitted to the hospital, as opposed to an average of 9 percent in other countries.

There were two strong predictors of these results, said Dr. Manesh Patel, senior author of the study at Duke University Medical Center.  Patients with multi-vessel disease were more likely to be readmitted because they were higher risk patients. The second strong predictor for any reason was if the patient person was being treated in the United States.

"This isn't telling us to stay in the hospital longer, but it does open up a conversation about how other countries perform differently," said Patel. "This will be important as we move forward with health care reform and figure out ways to provide sufficient care."

"We do a great job of opening up a patient's artery, but we need a more coordinated system in place that helps patients follow lifestyle changes, instead of the episodic nature of U.S. health care," continued Patel.

American doctors are more aggressive in treating patients, said Dr. Christopher Cannon, professor of medicine at Harvard Medical School. If patients experience any ischemia (reduced blood supply to the heart) post-surgery, doctors tend to want to readmit the patient to the hospital.

"I think also that U.S. patients demand top level care, so if there is a question of chest pain following a [heart attack], they get readmitted for evaluation just to be safe," said Cannon.

While the initial length of stay in the hospital tended to be shorter for patients in the U.S., doctors were hesitant to say that this is the reason for readmission.

"We think we stabilize patients sufficiently here, but there may be some patients who benefit from longer observation post [heart attack]," said Cannon. "I think, though, in general, we keep people in hospital an appropriate length of stay. But the issue of not as uniform follow-up after discharge is a system issue for the U.S.  Our care is a bit more fragmented, so [it is] not as well-coordinated, and then some patients can fall between the cracks and need readmission to get things re-stabilized."

Dr. William Abraham, professor of medicine, physiology and cell biology at the Ohio State University, said the findings highlight the trade-off between length of stay for the index hospitalization and 30-day readmission rate, but he noted that most health insurances in the U.S. do not support longer length of stays in hospitals.

"When the readmission rate is adjusted for LOS by country, the US no longer demonstrates a higher than average readmission rate," said Abraham.  "Thus, the desire to reduce length of stay and to reduce 30-day readmission rate may represent competing goals. Patients in the US should probably stay a bit longer in the hospital on average."

Beyond the delivery of important medical therapies and interventions, the hospitalization also serves as an important "teachable moment" for patients and their families, said Dr. Ty Gluckman, director of clinical excellence at the Providence Heart and Vascular Institute in Portland, Or.

Greater lengths of stay provide unique opportunities for patient education, not only about their disease process, but also identification of warning symptoms and signs, said Gluckman. They also allow patients to become familiar with new medications and identify potential side effects. And finally, longer length of stays engage patients and their families when they are most vulnerable and likely to be focused on future cardiovascular risk.

"These opportunities likely help in reducing the rate of early readmission," said Gluckman. "Given the uncertainty about what is the optimal length of stay after a myocardial infarction, it is nonetheless important for patients and their families to engage providers to be better educated about warning symptoms and signs, to better understand the medications they are prescribed and to understand what measures can be taken both short-term and long-term to reduce their cardiovascular risk."