[Surgical management of ventricular arrhythmia after myocardial infarction]

From December 1986 to December 1994, 36 patients underwent surgical treatments for intractable ventricular tachyarrhythmias after myocardial infarction. Preoperative electrophysiological studies confirmed inducibility of sustained monomorphic ventricular tachycardia and its resistance to antiarrhythmic drugs in all patients, 2 different concepts were assessed: 1) 22 non-guided surgical procedures were performed. 17 patients underwent Encircling thermic exclusion by Nd-Yag laser beam (Group A) and 5 patients underwent extended cryoablations (n = 5) with endocardial resections. Mean preoperative value of left ventricular function in Groups A and B were 35.23% and 30.20% respectively. 10 coronary bypasses (Group A: n = 8; Group B: n = 2) and 1 mitral valve replacement (Group A) were also performed. Perioperative mortality was 5.5% in Group A. No perioperative deaths occurred in Group B. Ventricular tachycardias recurred spontaneously in 2 patients (Group A) and 7 remained inducible after evaluation by electrophysiological studies. 2) 14 patients underwent extended cryoablations guided by intraoperative cardiac mapping, including endocardial resections in all cases. Mean preoperative value of left ventricular function was 32.80%. Mitral valve replacements were achieved in 2 cases, 1 perioperative death occurred (7.14%). Clinical recurrence of ventricular tachycardias concerned 1 patient (7.69%) and 2 remained inducible after electrophysiological studies (15.38%). We conclude that the better results obtained with cardiac mapping and cryoablations may be due to available detection and destruction of deep septal arrhythmogenic substrates. Moreover, cryoablation creates a nonarrhythmogenic scar and can be performed in papillary muscles while preserving the structure of the tissue. No postoperative alteration of left ventricular function was therefore observed.