Background: Atrial fibrillation (AF) is a common complication after coronary artery bypass grafting (CABG) operations. The aim of this prospective trial was to test the hypothesis that intraoperative high-rate atrial pacing may induce AF by mimicking rapid atrial tachycardia and can identify the patients at risk for postoperative AF. METHODS; Eighty patients having on-pump CABG without additional procedures were included in the study. After cannulation but before initiation of cardiopulmonary bypass two pacing wires were placed on the lateral surface of the right atrium. The right atrium was paced with the rate of 200 beats per minute for 10 seconds. If the patient was in sinus rhythm after the high-rate pacing, the pacing test was repeated with the rate of 250 and finally 300 beats per minute.
Results: Postoperatively AF developed in 28 patients (35%). The high-rate atrial pacing test induced AF in 27 patients (33.7%). Of the 28 patients who experienced AF during the postoperative period, 17 patients were inducible in the atrial-pacing test (sensitivity 0.61). Of the 52 patients who did not develop AF postoperatively, 42 patients were not inducible in the atrial-pacing test (specificity of the test was 0.81). Positive and negative predictive values of the test were 0.63 and 0.79, respectively.
Conclusions: The intraoperative high-rate atrial pacing test turned out to be a simple, safe, and fast way to identify the patients at risk for AF after CABG. The diagnostic accuracy of this test is sufficient to identify a group of patients to whom prophylactic treatment could be directed.