Ineffectiveness of anticoagulants in myocardial infarction

Evaluating the effectiveness of anticoagulants in the management of myocardial infarction showed no significant difference between the mortality rates of the control group and those of the treated groups when patients in the same PIR category were compared, and the finding that higher Pathologic Index Ratings are associated with higher mortality rates was confirmed.

Abstract

T he use of anticoagulants in the management of acute myocardial infarction is a widespread practice accepted by most clinicians as of considerable value. Published data on which this acceptance is based are numerous but only rarely include well-documented controls. Schnurl pointed out in 1953 that the prognosis of myocardial infarction is a function of many factors other than the simple presence of infarction, and that in order to serve as controls a group of patients with this diagnosis must be comparable in all ways to those in the treated group. He devised a system for evaluating the degree of illness of patients, the Pathologic Index Rating (PIR), by assigning numbers to various findings, such as cardiac decompensation, arrhythmia, shock, etc. (Table I). Use of this system allows patients with similar severity of illness to be paired for evaluation of treatment. His experience indicated that prognosis was predictable from the PIR, and that the use of anticoagulants did not alter the predicted mortality. Smart and Bruce2 applied the same criteria in a study of their patients with myocardial infarction and confirmed the finding that higher Pathologic Index Ratings are associated with higher mortality rates. Their” evaluation of the effectiveness of anticoagulants in the management of myocardial infarction showed no significant difference between the mortality rates of the control group and those of the treated groups when patients in the same PIR category were compared. The purpose of this paper is to report on another series in