Death rates from heart disease have plummeted in Britain, according to a new study by Oxford University researchers who suggest healthier lifestyles and better treatment and drugs have actually made hearts stronger.

Researchers studied 840,000 patients who suffered heart attacks between 2002 and 2010. Over that period, death rates dropped by 50 per cent for men and 53 per cent for women.

Fewer people died from the actual heart attacks, while post-attack survival rates rose, said Dr. Mike Rayner in a news release. Rayner was one of the Oxford researchers involved in the study.

Doctors aren't exactly sure what caused heart disease rates to plummet, but they suggest that better nutrition and reduced smoking rates played a part, as did efforts to cut cholesterol and lower high blood pressure.

Over the years, these lifestyle changes may have actually made hearts stronger, so that if a person does suffer a heart attack there is a better chance the patient will recover. The authors also noted that death rates from heart disease have been declining across the developed world since the 1970s.

"It is improvements in diets and nutrition, particularly in the type of fat we eat," Rayner said. "We've been switching from saturated to unsaturated fat. There has been a slight increase in fruit consumption . . . and a slight recent decline in salt consumption."

Medical advances also played a part. Doctors are able to diagnose heart problems more quickly and treat them more effectively. Procedures, such as an angioplasty -- in which a surgeon inserts a tiny tube to the heart to free blockages -- also save lives.

"It's a treatment that we're able to give patients with heart attacks when they come into hospitals," said London-based cardiology professor Adam Timmis. "The treatment has been revolutionized in the past five to 10 years or so."

Rayner said medical advances help but he thought lifestyle changes played a bigger role.

"The improvements in survival after an attack are not just down to improvements in treatment, in my view, but also to a decline in the severity of the disease -- again possibly due to lifestyle change.'

The Oxford researchers said the study is good news, but stressed that more can be done to further reduce heart disease fatalities.

The greatest decline in heart attacks was among middle-aged men and women, while smaller declines were found in younger and older age groups, the study showed.

"There is evidence from this paper and elsewhere that the decline in deaths is slowing -- particularly in younger age groups," Rayner said.