Prognostic value of strain and strain rate in the prediction of postoperative atrial fibrillation in patients undergoing coronary artery bypass grafting: a systematic literature review

Introduction: Atrial fibrillation (AF) is a common dysrhythmia postoperatively after coronary artery bypass grafting (CABG). Myocardial strain and strain-rate imaging is used for the assessment of postoperative atrial fibrillation (POAF) as a new echocardiographic method. Methods: PubMed and Scopus were searched thoroughly using the following search terms: (strain and strain rate) AND (atrial fibrillation OR AF) on March 2015 to find English articles in which the strain and strain-rate echocardiographic imaging had been used for the evaluation of AF in patients undergone CABG. Full text of the relevant papers was fully reviewed for data extraction.Result: Of overall 6 articles found in PubMed, 10 records found in Scopus and 4 articles found through reference list search, only 6 papers fully met the inclusion criteria for further assessment and data extraction. The results of strain and strain-rate assessment showed that in total of 542 patients undergoing CABG, POAF occurred in 106 patients. Studies showed that the reduction of left atrial (LA) strain rate is correlated with AF. Consistently, the results of present review showed that LA strain and strain-rate in patients who developed AF postoperatively after CABG are significantly reduced, suggesting that strain and strain-rate could be a predictor of POAF.Conclusion: Based on the obtained results, strain and strain-rate is a suitable and accurate echocardiographic technique in the assessment of left atrial function , and it might be helpful to detect the patients who are at high risk of POAF.