ANTIARRHYTHMIC DRUG PRESCRIPTION IN PATIENTS AFTER MYOCARDIAL-INFARCTION IN THE LAST DECADE - EXPERIENCE OF THE -STUDIO-DELLA-SOPRAVVIVENZA-NELLINFARTO-MIOCARDICO (GISSI)

Background: Recent clinical trials have shown increased, rather than d ecreased, mortality in patients treated with antiarrhythmic drugs afte r acute myocardial infarction. Objective: To determine whether these f indings had an impact on prescription of antiarrhythmic drugs after ac ute myocardial infarction. Methods: We retrospectively analyzed the cl ass I and III antiarrhythmic prescription data of 38 072 patients with acute myocardial infarction enrolled in three large randomized clinic al trials endorsed by a highly representative sample (about 75%) of It alian coronary care units during the last 10 years. The first study wa s conducted in 1984 to 1985; the second, in 1988 to 1989; the pilot fo r the third, in 1991; and the third, in 1991 to 1994. Results: Total c lass I and III antiarrhythmic prescriptions after acute myocardial inf arction was halved during the last decade, from 11.9% at discharge and 14.4% at follow-up in 1984 to 1985 to 5.8% and 5.8%, respectively, in 1991 to 1994. The trend was independent of the different distribution s in the three studies of the patients' characteristics associated wit h antiarrhythmic use tie, age greater than or equal to 70 years, anter ior acute myocardial infarction, ventricular fibrillation during hospi talization, and Killip class greater than or equal to 2 at randomizati on). The same decreasing trend was observed for each antiarrhythmic dr ug. The drug most widely used was amiodarone, accounting for about hal f of the antiarrhythmic prescriptions, followed by mexiletine hydrochl oride and propafenone hpdrochloride; flecainide acetate was dropped fr om the prescription list after the publication of the Cardiac Arrhythm ia Suppression Trial results. Conclusion: The negative results of the recent clinical trials on class I antiarrhythmic drug use alter acute myocardial infarction have been rapidly transferred into routine clini cal practice in Italy, since the proportion of patients who received c lass I and III antiarrhythmic drugs after acute myocardial infarction was halved from the early 1980s to the early 1990s.