The regulatory body, the Irish Medicines Board, has confirmed that up to 56 potentially defective pacemakers have been implanted in patients in Ireland.
The devices made by US firm Guidant have not been sold or implanted in this country in the last four years.
A sealing component used in the devices affected may experience gradual deterioration, resulting in a higher than normal moisture content within the pacemaker case.
The board says that all patients with affected devices have been identified and will be contacted by physicians in Ireland.
Patients implanted with the affected devices who experience symptoms such as prolonged rapid heart rate, light-headedness, blackouts, palpitations, increased shortness of breath, dizziness, ankle-swelling or increased cardiac symptoms, are asked to seek medical attention.
The devices were made between 25 November 1997 and 26 October 2000.
The Guidant Corporation has a base in Clonmel, Co Tipperary.
