Abstract 16387: Surgery for LV Summit VT
Introduction: The LV summit is the most superior region of the LV, surrounded by the LAD, LCX, and anterior interventricular vein. Endocardial and epicardial catheter ablation of LV summit VT frequently fails or is not indicated, because of thick LV mass that hampers transmural ablation and a high possibility of injury to the major coronary vessels. We reviewed our experience to examine the effectiveness of surgery for LV summit VT.
Methods: Of 32 patients who underwent surgery for non-ischemic VT, 8 patients had a VT focus or substrate at the LV summit. All patients were male and the age was 51±21 years old. Indication for surgery was incessant VT in all patients, including 5 with VT storm. All patients had been placed on oral amiodarone and 4 patients had implanted with an ICD preoperatively. All patients had undergone one or two sessions of unsuccessful catheter ablation, including epicardial ablation in 4 patients.
Surgical cryoablation was performed at the earliest activation site determined by intraoperative epicardial mapping using CARTO system. The coronary vessels were carefully dissected and snared, epicardial fat was removed by using harmonic scalpel, and then cryoablation was applied directly on the myocardium. Cryoablation of the LV endocardium immediately beneath the epicardial earliest activation site was performed by introducing a cryoprobe into the LV cavity through an aortotomy, except in one patient in whom the cryoprobe was directly introduced through an LV incision. The thickness at the VT focus determined by echocardiography was 15±2 mm.
Results: There were no operative death and no morbidities related to the intraoperative mapping, cryoablation, or coronary artery manipulation. Clinical and non-clinical VT occurred in two patients on the first and fifth postoperative day, respectively. Both the patients underwent additional endocardial catheter ablation. All the patients have been free from VT and ICD shocks during a follow up period of 51±42 months.
Conclusions: Surgical cryoablation guided by intraoperative mapping was effective for LV summit VT. The substrate of the VT might be intramural origin in some patients.
Author Disclosures: T. Nitta: None. S. Sakamoto: None. Y. Miyagi: None. Y. Kawase: None. M. Morishima: None. J. Aoyama: None. M. Shibata: None. Y. Ishii: None. K. Takahashi: None. H. Hayashi: None. H. Murata: None. W. Shimizu: None.
- © 2016 by American Heart Association, Inc.