Surgery for postinfarction ventricular tachycardia: is it obsolete?

Comprehensive arrhythmic surgery for sustained ventricular tachycardia revisited

A 68-year-old woman with a history of old inferior myocardial infarction was admitted because of sustained ventricular tachycardia. Double vessel coronary disease was found with subtotal obstruction of the right coronary artery (#1) and severe stenosis of the left circumflex coronary artery (#13). Dilated left ventricle with a large ventricular aneurysm at the inferior wall and severely reduced systolic function were also present. A comprehensive surgical ablation using subendocardial resection and cryoablation was performed in combination with aneurysmectomy, left ventricular reconstruction, and coronary bypass grafting to the circumflex coronary artery. An implantable cardioverter-defibrillator was also implanted. She has remained well without recurrence of sustained ventricular tachycardia for one year. Although radiofrequency catheter ablation is nowadays considered a first-line therapy for patients with sustained ventricular tachycardia, surgical ablation remains a valuable option for selected patients, particularly for those requiring left ventricular aneurysmectomy and coronary artery bypass grafting, in order to gain a better long-term prognosis through total cure of ventricular tachycardia. <Learning objective: Although radiofrequency catheter ablation is nowadays considered a first-line therapy for patients with sustained ventricular tachycardia, surgical ablation remains a valuable option for selected patients, particularly for those requiring left ventricular aneurysmectomy and coronary artery bypass grafting, in order to gain a better long-term prognosis through total cure of ventricular tachycardia.>.

Prophylactic catheter ablation for the prevention of defibrillator therapy

BACKGROUND

For patients who have a ventricular tachyarrhythmic event, implantable cardioverter-defibrillators (ICDs) are a mainstay of therapy to prevent sudden death. However, ICD shocks are painful, can result in clinical depression, and do not offer complete protection against death from arrhythmia. We designed this randomized trial to examine whether prophylactic radiofrequency catheter ablation of arrhythmogenic ventricular tissue would reduce the incidence of ICD therapy.

METHODS

Eligible patients with a history of a myocardial infarction underwent defibrillator implantation for spontaneous ventricular tachycardia or fibrillation. The patients did not receive antiarrhythmic drugs. Patients were randomly assigned to defibrillator implantation alone or defibrillator implantation with adjunctive catheter ablation (64 patients in each group). Ablation was performed with the use of a substrate-based approach in which the myocardial scar is mapped and ablated while the heart remains predominantly in sinus rhythm. The primary end point was survival free from any appropriate ICD therapy.

RESULTS

The mortality rate 30 days after ablation was zero, and there were no significant changes in ventricular function or functional class during the mean (+/-SD) follow-up period of 22.5+/-5.5 months. Twenty-one patients assigned to defibrillator implantation alone (33%) and eight patients assigned to defibrillator implantation plus ablation (12%) received appropriate ICD therapy (antitachycardia pacing or shocks) (hazard ratio in the ablation group, 0.35; 95% confidence interval, 0.15 to 0.78, P=0.007). Among these patients, 20 in the control group (31%) and 6 in the ablation group (9%) received shocks (P=0.003). Mortality was not increased in the group assigned to ablation as compared with the control group (9% vs. 17%, P=0.29).

CONCLUSIONS

In this randomized trial, prophylactic substrate-based catheter ablation reduced the incidence of ICD therapy in patients with a history of myocardial infarction who received ICDs for the secondary prevention of sudden death. (Current Controlled Trials number, ISRCTN62488166 [controlled-trials.com].).