Newark Hospital in Nottinghamshire is no longer being sent patients who call an ambulance for a suspected stroke or heart attack.
The patients will go to King's Mill Hospital or Nottingham City Hospital for specialist treatment.
The move is part of a programme to offer patients a better chance of recovery, Sherwood Forest Hospitals NHS Trust said.
Patients will get clot-busting drugs or angioplasty at the specialist units.
Health officials said many patients would be transferred to the Newark Hospital for further care and rehabilitation after a stroke.
The government review said stroke care and heart facilities available at King's Mill Hospital and at Nottingham City Hospital were better equipped to increase survival rates and improve recovery times.
Dr M Zahid Noor, Newark Hospital's medical service director, said: "Newark Hospital has previously offered a good quality service to these patients, but cannot offer the new improved service models, teams and facilities now available at King's Mill and City Hospitals."
The change is not linked to a separate decision to downgrade the hospital's accident and emergency department to a minor injury unit, a hospital official said.