Spatial relationship between left atrial roof or superior pulmonary veins and bronchi or pulmonary arteries by dual-source computed tomography: implication for preventing injury of bronchi and pulmonary arteries during atrial fibrillation ablation

Aims Bronchi or pulmonary arteries (PAs) could be injured during atrial fibrillation (AF) ablation. Therefore, the aim of the present study was to evaluate the spatial relationship between left atrial roof or superior pulmonary veins (PVs) and neighbouring structures of AF patients and provide anatomic guidance for AF ablation to avoid injuring bronchi or PAs. Methods and results A dual-source computed tomography (DSCT) scan was used to depict the left atrium (LA), PVs, and nearby structures including bronchi and PAs in 58 patients with drug-refractory AF (mean age, 64 +/- 9 years). The distance between LA roof or superior PVs (SPVs) and bronchi or PAs was measured. The average minimal distances from the left, middle, and right points of the LA roof to the principal bronchi were 17.0 +/- 6.4, 23.7 +/- 5.1, and 23.2 +/- 7.7 mm, respectively. The LA roof was closer to the right PA (RPA) than the left PA (LPA) for more than 90% of patients. The average minimal distances from the left, middle, and right points of the LA roof to the PAs were 8.3 +/- 5.0, 5.9 +/- 3.1, and 6.0 +/- 2.8 mm, respectively. The average minimal distances between the left superior pulmonary vein and bronchi or LPA were 0.32 +/- 0.79 or 0.4 +/- 1.0 mm, respectively. The average minimal distances between the right superior pulmonary vein and bronchi or RPA were 0.27 +/- 0.94 and 0.0 +/- 0.1 mm, respectively. Both of the root parts of SPVs of most patients were in direct contact with branches of trachea and PAs. Conclusion Dual-source computed tomography provides important imaging information for determining the relationship between LA, PVs, and neighbouring structures. Use of pre-procedural cardiac CT scans may help avoid ablation-induced injury of bronchi and PAs.