Abstract
The cause of atrial fibrillation (AF) after coronary artery bypass grafting (CABG) is not clear yet. Speculating that the extension of pulmonary vein (PV) would induce AF after CABG, we analyzed 39 cases in which a Swan-Ganz catheter was inserted at the onset of AF. The cardiac index (CI), systolic pulmonary artery pressure (sPA), diastolic pulmonary artery pressure (dPA) were measured continuously after operation. The “occupation index” was defined as “(value just before the AF onset-minimum value)/(maximum value-minimum value) × 100%.” The mean values of the occupation index for CI, sPA and dPA were 16±30%, 77±36%, 76±38% (mean±SD) respectively. Furthermore, cases in which CI just before the AF onset showed a minimum value in all the collected data consisted of 27 of the 39 cases (69%), and sPA/dPA just before the AF onset showed a maximum value in all the collected data in 26/25 of the 39 cases (67%, 64%). About two-thirds of AF cases occurred in the descending phase of CI, and in the ascending phase of sPA/dPA. We considered these conditions to be equivalent to the extension condition of PV and surmised that PV extension might be one of the causes of AF after CABG.
