title: Value of the signal-averaged P wave analysis in predicting atrial fibrillation after cardiac surgery.
abstract: Atrial fibrillation (AF) is the most common sustained arrhythmia occurring after cardiac surgery. Beside important implications regarding patient recovery, AF has been shown to substantially lengthen hospital stay--our recent study found a 3-day prolongation after adjusting for all other significant factors. Identification of those at highest risk of AF by clinical or noninvasive characteristics may be a useful strategy for targeted prophylactic therapy. Our data have shown that prolonged atrial conduction as assessed by analysis of the P wave duration from the signal-averaged electrocardiogram (SAECG) imparts a four fold increase in risk for postoperative AF, independently of other measured variables. In addition, abnormal conduction was present on the preoperative P wave ECG (P-SAECG), implying a preexisting substrate that is triggered by surgery. The use of combination abnormal noninvasive variables (eg, abnormal P-SAECG and low left ventricular ejection fraction) can identify groups with a 50% risk of AF, which is nine times as high as when both tests are normal. Thus, the P-SAECG is a useful and accurate predictor of AF after cardiac surgery.
authors.affiliation: Division of Cardiology, St. Luke's-Roosevelt Hospital Center and Columbia University College of Physicians and Surgeons, New York, New York 10025, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Tamis
authors.forename: J S
authors.initials: JS
authors.lastname: Steinberg
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D004562:Electrocardiography; D006801:Humans; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012372:ROC Curve; D012307:Risk Factors; D012815:Signal Processing, Computer-Assisted