More patients are getting life-saving treatment quickly after a heart attack, according to a national survey.
An audit by the Royal College of Physicians showed 64% of patients in England and 41% in Wales were given "clot-busting" drugs within an hour.
This is a rise of six percent and 11% respectively over 12 months.
Overall, heart attack death rates have fallen, with 12 fewer deaths per 1,000 heart attacks, but the report stressed there was still room for improvement.
Nonetheless, the government-appointed director for heart disease, Professor Roger Boyle, said the NHS now offers a "high level of excellence" in heart attack services.
"Clot-busting", or anti-thrombolytic drugs, are proven to improve the chances of heart attack patients making a full recovery - with the most benefit if they are given within the first hour after a heart attack.
The government set targets for hospitals and ambulance services in the NHS when it became clear that many patients were not getting the drugs at all, or waiting several hours for them.
The differences between Wales and England revealed in the Myocardial Infarction National Audit Project (MINAP) are put down to the more rural nature of many areas of Wales, which mean slower response times for ambulance crews.
Nearly all ambulance services have now trained their paramedics to be able to give the treatment before the patient reaches hospital.
Straight to theatre
The other big change highlighted by the report is the increasing use of emergency procedures to help heart attack patients.
In England, there are 35 hospitals now offering "primary angioplasty" for patients, a procedure where the obstructed heart artery is widened so blood can flow, and the number of patients dealt with this way has nearly doubled in one year.
These changes have contributed to a fall in the percentage of people killed by heart attacks in England and Wales.
In 2005-2006, just over 12% of heart attack patients died within 30 days. This year, it is 11.2%, representing 12 more heart attack survivors for every 1,000 heart attacks.
Professor Boyle said: "Patients with heart attack are being treated in the NHS to a high level of excellence.
"The remarkable improvements seen each year since the inception of MINAP are a tribute to the many staff across the country who look after heart attack patients, including the ambulance services, A&E departments, cardiac care units as well as the MINAP team itself.
A spokesman for the British Heart Foundation said that it was "thrilled" that the emergency services were having such a positive impact.
"Every second really does count in the fight to save lives.
"However, while the MINAP data shows that the emergency services are making great progress, sadly it's often the person having the heart attack who continues to put their own life at risk.
"Far too many people doubt their symptoms, worrying that it may be a false alarm or they mistake the pain for a bad bout of indigestion."