Even slight reductions in the delay to deliver emergency angioplasty improves survival of all patients with acute myocardial infarction, regardless of the interval between onset of symptoms and hospital arrival, according to an article in the June 6 issue of the Journal of the American College of Cardiology.

“There is a belief among some clinicians that patients presenting late will not benefit from faster door-to-balloon time. We were able to show that door-to-balloon time matters for all patients regardless of time to presentation.

Furthermore, we were able to show that door-to-balloon time mattered for both low- and high-risk patients. In summary, all patients can benefit from shorter door-to-balloon times,” said Robert L. McNamara, MD, MHS, lead author, of the Yale University School of Medicine.

Previously it was not clear whether patients who had had symptoms for a few hours before reaching the hospital benefited from making every effort to minimize time from presentation to catheterization lab.

The current analysis used data from a US registry in which hospitals voluntarily enter information about patients with myocardial infarction. In particular, researchers analyzed data on 29,222 patients treated with angioplasty from 1999 to 2002 at 395 hospitals within six hours of alerting health care providers to their symptoms.

Overall, when patients underwent angioplasty within 90 minutes of hospital arrival, there was 3 percent in-hospital mortality. In-hospital mortality rate rose to 7.4 percent for patients who were in the hospital for more than 3 hours before being treated.

Analysis of subgroups who arrived at a hospital within an hour of reporting symptoms, between one and two hours, or longer than two hours, showed the same pattern: within each subgroup, faster action in the hospital meant lower death rates. The same benefits of swift hospital response were seen regardless of whether patients were high-risk or not.

The results of this study indicate that while getting to the hospital as quickly as possible is vital, rapid action by the hospital makes just as much of a difference for patients who come in late as it does for those who arrive close to onset of symptoms.

“I think the most surprising finding is that mortality decreases with shorter door-to-balloon time to a similar degree for each group, regardless of time to presentation. Many clinicians think that time matters much more for early presenters than for late ones,” McNamara said.

Jeffrey J. Cavendish, MD, from the Naval Medical Center in San Diego, California, who was not connected with this study, said the results emphasize the importance of streamlining hospital procedures: “The main message that this study re-enforces is not only the concept of "time is muscle," but that "time is life.”