Evaluation of electrical reconnection after pulmonary vein isolation using 320-slice computed tomography

Abstract

Background: Pulmonary vein isolation (PVI) has been used effectively to treat atrial fibrillation (AF). However, one of the most important limitations of catheter ablation for AF is the rate of recurrence of atrial tachyarrhythmias, due predominantly to electrical reconnection of the pulmonary veins (PVs). Therefore, it would be useful if we could detect electrical reconnection of the PVs noninvasively, using multi-slice computed tomography (MSCT). We hypothesized that the absence of PV contraction could represent persistent electrical PV isolation after catheter ablation. Materials and methods: Twenty-eight patients (59.5±11.2 years, 23 males) who underwent the second session for the recurrent AF were enrolled. MSCT was performed twice, before the first session and before the second session. Images were reconstructed at 10 phases of one cardiac cycle (from 5% to 95% of the R-R interval). Using multi-planar reconstruction, the location of the PV ostium was defined, and the ejection fraction (EF) of each PV was calculated as the volume change of the first 10mm from the ostium using Simpson's disc methods. Each pulmonary vein was divided into the two groups according to the presence of electrical reconnection. The EFs of each PV (right superior PV: RSPV, right inferior PV: RIPV, left superior PV: LSPV, left inferior PV: LIPV) were calculated in the first and the second MSCT scan. Results: The number of reconnected PVs were 15 in RSPV, 14 in RIPV, 12 in LSPV and 12 in LIPV, respectively. In PVs without electrical reconnection, the EFs of PVs significantly decreased in RSPV, RIPV and LSPV. However, in PVs with electrical reconnection, the EFs of PVs did not change significantly in all PVs (see table). View this table: Conclusion: MSCT may be useful for the non-invasive evaluation of electrical PV reconnection.