An Assessment of Long-term Anticoagulant Administration after Cardiac Inarction

Between November 1955 and May 1960 a controlled trial was carried out to compare the clinical progress of patients who had recovered from the acute stage of cardiac infarction when given high dosages of phenindione with the experience of a similar series of patients given low dosages. The patients on the high-dosage regime were given sufficient phenindione approxi- mately to double the one-stage prothrombin time, while those on the low-dosage regime were given tablets containing only 1 mg. of phenindione. New patients were admitted to this trial between November 1955 and March 1958. The design of the trial and the progress of these patients up to the end of 1958 have already been given (Report to M.R.C., 1959). The present report describes the subsequent progress of the patients up to May 1960, when the trial in its original design was dis- continued. A later phase of this trial extending up to December 1962 is also described.