Ambulance crews will now take patients with blocked arteries straight to Royal Berkshire Hospital's cardiac unit for an emergency angioplasty day or night.
It follows a successful pilot project, and patients will normally be treated within an hour of suffering symptoms of a heart attack. Launched on 1 April, the service has so far successfully treated four patients. The procedure sees a catheter with a deflated balloon at its tip inserted into any blockage in the artery.
A spokesman for the hospital trust said: "The hospital has been running the angioplasty service for a few months now during daytime hours and took the decision to make the service available 24 hours a day, seven days a week."