Their findings are based on figures from hospital treatment and outcomes for 44,372 patients admitted to 113 hospitals in 14 countries with heart attacks or unstable angina (threatened heart attacks).
In patients with a severe heart attack, death rates reduced from 8.4 to 4.5 per cent. Their risk of heart failure almost halved as well. This equates to 39 fewer deaths and 90 less patients with new heart failure for every 1,000 patients entering hospital.
Professor Keith Fox of Edinburgh University said that until now there has been a "substantial gap" in knowing how new drugs and procedures are able to affect hospital outcomes.
Advances which have contributed to the decline in heart attack deaths include the use of beta blockers; statins; and anti-clotting agents, he claims.
"However, these long-term prevention methods do not account for improved outcomes while patients are in hospital, which must be down to the acute treatments given after admission. We have taken into account risk factors and the improved outcomes are not because patients are less unwell when they arrive at hospital," Professor Fox added.
"Our study supports the fact that hospitals are using new treatments effectively. Patients now have a much reduced risk of dying or having another stroke while being treated in hospital and are also less likely to suffer a stroke or further heart attack once they have been discharged."
Commenting on the study's findings, Professor Peter Weissberg, medical director at the British Heart Foundation (BHF), said: "This is a great example of why long-term investment in heart research is vital.
"The study shows that fewer people are dying, and fewer are developing debilitating heart failure thanks to research evidence prompting these hospitals to improve the way they treat people with heart disease."
The research is published in the Journal of American Medical Association.
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