There has been a 40% reduction in deaths in hospitals due to heart attacks since 2007.
The findings are part of a report from the National Office of Clinical Audit - NOCA.
It looked at mortality rates across six medical conditions in 44 publicly funded hospitals.
It found there was a 36% fall in deaths due to strokes, while mortality rates for pneumonia dropped by 20%.
Dr Brian Creedon says improvements in heart attack treatment are partly down to improved training.
He said: "Some of our ambulance personnel can diagnose a heart attack at somebody's house and bring them to the right hospital where the right treatmeant is."