Value of preoperative echocardiography in the prediction of postoperative atrial fibrillation following isolated coronary artery bypass grafting

The value of echocardiography, especially tissue Doppler imaging (TDI), in the assessment of risk of postoperative atrial fibrillation (AF) after coronary artery bypass grafting (CABG) is not clear. One hundred two consecutive patients (80 men; mean age 61 +/- 10 years) who underwent elective isolated CABG were included in the study. All patients underwent conventional transthoracic echocardiography and TDI of the left and right heart before surgery. Also, 24-hour Holter recordings were obtained for all patients. The study end point was the development of postoperative AF. The surgical mortality rate was 2%. Postoperative AF occurred in 18 patients (18%). Patients with postoperative AF have been significantly older than patients without postoperative AF (73 +/- 7 vs 58 +/- 9 years, respectively; p <0.001). Compared with patients without postoperative AF, a significantly higher proportion of patients with postoperative AF experienced paroxysmal AF before surgery (6% vs 33%, respectively; p = 0.001). Patients with postoperative AF had a significantly larger mean left atrial diameter compared with patients without postoperative AF (37 +/- 3 vs 35 +/- 3 mm, respectively; p = 0.012). Multivariate logistic regression analysis identified age as the most significant predictor of postoperative AF (odds ratio 1.254, 95% confidence interval 1.127 to 1.396; p <0.001). Of the echocardiographic variables, only left atrial diameter was identified as a significant predictor of postoperative AF (odds ratio 1.250, 95% confidence interval 1.055 to 1.562; p = 0.047). In conclusion, in the prediction of postoperative AF after isolated CABG, preoperative transthoracic echocardiography, including both conventional echocardiography and TDI, is of little value.