Ventricular fibrillation complicating acute myocardial infarction: reasons against the routine use of lidocaine.

Because of recent recommendations that lidocaine be used prophylactically in all coronary care unit (CCU) patients with suspected myocardial infarction (MI), an approach not used in our CCU, we analysed our experience with ventricular fibrillation (VF) occurring in the setting of an acute MI. The frequency of VF in all patients was 3.2%. In MI patients 5.7%, of primary ventricular fibrillation (PVF) 2.8%, and of complicating ventricular fibrillation (CVF) 6.8%. All patients with PVF were resuscitated immediately. There was an increased in-hospital mortality for patients with VF compared to patients without VF; however, the increased mortality did not seem to result directly from VF. The long-term survival of PVF patients who survived to discharge was excellent (80% at 58 months). The routine use of prophylactic lidocaine would have been of no potential benefit in 96.8% of our patients, subjecting them to extra expense and possible toxicity. Since we have found no compelling evidence that the prophylactic administration of lidocaine can reduce mortality, we do not recommend this therapy for acute MI patients in our CCU.