Deaths from severe heart attacks after hospital admission have nearly halved in six years, a study shows.
The international team, which studied 44,372 patients in 14 countries, found that death rates fell from 8.4% to 4.5% between 1999 and 2006.
Treatments such as angioplasty to unblock arteries and anti-clotting drugs were the key, the Journal of the American Medical Association reported.
They also led to less heart failure and fewer repeat heart attacks and strokes.
It is well-established that heart disease rates have been falling for several decades due to healthier lifestyles and better preventative treatment, such as statins.
But this is the most comprehensive study looking at the success of hospital treatment once patients are admitted with heart attacks or serious angina.
As well as the fall in death rates for severe heart attacks, where the arteries were completely blocked, deaths from milder attacks were also reduced from 2.9% to 2%.
Both patients with severe and milder heart attacks were less likely to suffer from strokes and further heart attacks in the following months.
The risk of critical heart failure, a weakening of the heart which can be brought on by heart attacks, fell from 7.1% to 4.7%.
The use of drugs such as beta blockers and aspirin have been key to this progress, the researchers added.
Lead researcher Professor Keith Fox, from Edinburgh University, said it was already known these treatments were effective.
But he 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."
Professor Peter Weissberg, medical director of the British Heart Foundation, added: "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 people are developing debilitating heart failure thanks to research evidence prompting these hospitals to improve the way they treat people with heart disease."
The study involved patients being treated in over 100 hospitals in countries such as the UK, Canada, Germany, France and Spain.