Durability of EIVM-induced lesions and persistence of MI block
Each of the 24 patients were referred for redo CA of symptomatic recurrent AF or AT (Table 3). At least one PV was reconnected in 7 (29%) patients and the roof line was reconnected in 6 (25%). The MI was reconnected in 5 of the 20 (25%) patients with complete MI block at the index procedure. The site of reconnection was endocardial at the lower (mitral annulus) extremity in 2 patients and was epicardial in the CS in 3. The 4 patients with failure to obtain MI block at the index procedure showed residual conduction at the left PV ridge aspect of the MI. The EIVM-created lesion was maintained in every patient. The median area of bipolar voltage < 0.05 mV in the VOM region (13.1 cm2 [IQR 8.1–15.9]) was comparable to the area present immediately after EIVM (median 12.4 cm2 [IQR 7.6–15.7], p=0.27) (Figure 2). At the end of the redo procedure, bidirectional block of all lines including MI was achieved.