Prophylactic Lidocaine in Acute MI

To the Editor.—  MacMahon et al¹ recently reported the effect of prophylactic lidocaine in the therapy of acute myocardial infarction, noting that, even today, we do not have enough evidence to support such use of prophylactic lidocaine. In their extensive reference list, the authors' earliest relevant reference is from 1967, in which Gianelly et al² suggest the possible use of lidocaine to prevent ventricular arrhythmias in the coronary care unit setting.In the same year, our detailed report in another journal³ dealt with the prophylactic use of procainamide and certain other intramuscular drugs in patients before admission to the hospital with coronary diagnoses. The primary point of our lengthy report and subsequent commentary⁴ was to indicate that it was not possible to recommend any single-drug therapy in the prophylactic treatment of acutely ill coronary patients. Rather, we pointed out that one probably must use a combination