Surgical management of sustained ventricular arrhythmias presenting within eight weeks of acute myocardial infarction

Intraoperative identification of a radiofrequency lesion allowing validation of catheter mapping of ventricular tachycardia with a computerized balloon mapping system

Radiofrequency current was utilized to mark the anatomic location of earliest endocardial activation during catheter mapping of ventricular tachycardia. Intraoperative identification of the radiofrequency lesion allowed validation that the site of earliest endocardial activation determined by a catheter mapping study was the same as assessed by a computerized balloon mapping system. Radiofrequency current may be a useful method of marking areas of endocardium thought to be potential sites for ablative surgery as well as allowing correlation between different mapping techniques.

Surgical therapy for drug-refractory ventricular tachycardia: results with mapping-guided subendocardial resection

Surgical therapy with mapping-guided subendocardial resection was used in 30 patients with drug-refractory ventricular tachycardia. Results of preoperative, intraoperative and postoperative electrophysiologic evaluation and long-term clinical follow-up are reported. Left ventricular aneurysm was located in the inferior wall in 8 patients and in the anterior wall in 22. Left ventricular mapping was performed in 15 patients preoperatively and in all 30 patients intraoperatively. Subendocardial resection was supplemented with cryoablation in 26 patients and with laser photocoagulation in 4. Coronary bypass surgery was performed in 27 patients. The surgical mortality rate was 10%; the three deaths were due to cardiogenic shock, pneumonia and sepsis, respectively. At postoperative electrophysiologic study, ventricular tachycardia was inducible in 8 (30%) of 27 patients. Previously ineffective antiarrhythmic drugs were effective in preventing the induction of ventricular tachycardia in four of these eight patients. Two of the remaining four patients received an automatic implantable cardioverterdefibrillator; the other two were treated with amiodarone. At a mean follow-up period of 18 +/- 17 months (range 1 to 52), there has been one sudden death and one nonfatal recurrence of ventricular tachycardia in the 18 patients without inducible arrhythmias postoperatively. Among the eight patients with inducible ventricular tachycardia after subendocardial resection, there has been one nonfatal ventricular tachycardia recurrence. Thus, among the 27 patients surviving surgery, 17 (63%) were cured with surgery alone, and another 7 (26%) had their ventricular tachycardia controlled with drugs (n = 5) or the defibrillator (n = 2). Inability to completely map the tachycardia, a clinical history of cardiac arrest requiring resuscitation and the presence of myocardial infarction within 2 months predicted postoperative arrhythmia inducibility and recurrence.

Neodymium:YAG laser photocoagulation: a successful new map-guided technique for the intraoperative ablation of ventricular tachycardia

Neodymium:YAG laser photocoagulation was used in the intraoperative treatment of drug-resistant ventricular tachycardia (VT) in 17 consecutive patients. The cause of VT was previous myocardial infarction in 15, sarcoid in one, and idiopathic in one patient. Electrophysiologic studies were performed preoperatively, before hospital discharge, and 8 to 12 weeks and 1 year after surgery. At surgery, laser photocoagulation was performed on the normothermic heart during VT. Surgical mortality was 11.7%. There was one late nonarrhythmic death 35 days postoperatively. There were 55 VT morphologies. Laser successfully abated 52 of 55. Associated use of cryoablation was required in two of 55. One VT in the patient with sarcoidosis was not successfully ablated but was controlled by procainamide. In the long-term survivors with VT due to myocardial infarction the surgical cure rate was 100%, i.e., no spontaneous or inducible VT. Follow-up ranges from 6 to 18 months (mean 11.8 +/- 4.3). Nd:YAG laser photocoagulation is an effective addition to the operative treatment strategies for VT.