THE LONG-TERM OUTCOME OF VISUALLY DIRECTED SUBENDOCARDIAL RESECTION IN PATIENTS WITHOUT INDUCIBLE OR MAPPABLE VENTRICULAR-TACHYCARDIA AT THE TIME OF SURGERY

Introduction: In prior studies, 20% to 40% of patients undergoing sube ndocardial resection (SER) for ventricular tachycardia (VT) could not be mapped intraoperatively because the VT was either noninducible or n onmappable following the ventriculotomy. The optimal surgical approach to such patients is not known. Methods and Results: In this study, we retrospectively compared the long-term survival and functional outcom e of 29 patients with VT and prior myocardial infarction who were eith er noninducible or nonmappable intraoperatively and underwent a visual ly directed extended SER. These results were then compared to 85 patie nts who had inducible VT intraoperatively and underwent a map-guided s equential SER. The two patient groups had different clinical character istics. The visually directed cohort was more likely to be male, exper ienced fewer VT episodes before surgery, and underwent fewer antiarrhy thmic drug trials prior to resection. In addition, the visually direct ed group had slower VT induced ata preoperative electrophysiologic stu dy and was less likely to present to the operating room in shock or in cessant VT than the map,guided group. The postoperative VT clinical re currence or inducibility rate was 14% in both the;visually directed an d map-guided groups. The long-term actuarial survival at 1, 3, and 5 y ears was 93%, 86%, and 75%, respectively, in the visually directed gro up, compared to 77%, 58%, and 58%, respectively, in the map-guided gro up (P=0.06). There were no documented nonfatal recurrences of VT in ei ther group. At 24 months following surgery; 77% of patients who had a visually directed SER were in New York Heart Association Functional Cl ass I or II, compared to 46% of patients who underwent a map-guided SE R (P<0.05). Conclusion: In patients with VT and prior myocardial infar ction, the inability to induce or map the VT in the operating room doe s not preclude a favorable long-term outcome if a visually directed ex tended SER technique is used.