Role of LA strain assessed by speckle tracking echocardiography in predicting patients who develop POAF after a coronary artery bypass surgery

Abstract

\n \n \n To evaluate the correlation between left atrial dysfunction assessed by speckle tracking echocardiography and development of postoperative atrial fibrillation (POAF) in patients undergoing coronary artery bypass grafting. To determine the role of coronary risk factors in development of POAF.\n \n \n \n Patients undergoing CABG from January 2019 till June 2020 in Apollo institute, fulfilling the inclusion and exclusion criteria were included.Total of 200 patients were followed.They were subjected to LA strain and strain rate analysis by speckle tracking.\n \n \n \n The incidence of POAF in our study was 24% (n=48). The mean age of this study population was 59.13 years. The patients who developed POAF were older (68.5±9.048 vs 58.39±9.74 years, p value=0.05) than those with no POAF. POAF occurred in 2 phases. the highest proportion of POAF occurrence noticed on postoperative day 2. Among the total POAF cases 79.% occurred within the first 48 hours and 20.8% occurred later (p=0.001). Among the 48 patients who developed POAF, 5 of them developed recurrence during their hospital stay. They had reverted to sinus rhythm following anti-arrhythmic medication for a duration of >24 hours, but went on to develop recurrence of AF at a later. 4 among them reverted to sinus rhythm at discharge while 1 continued to remain in AF at discharge.The duration of hospital stay for patients with POAF group was 10.4 days compared with 10.04 days for those without POAF. Similarly the post-operative stay in the hospital was 7.4 days for the POAF group and 7.04 days for the NO POAF.There was no added economic impact secondary to AF.Comparing the values of left atrial volume index of both the groups it was derived that the mean LAVI value of the POAF group was 26.84+3.654 ml/m2 and that for the NO POAF group was 26.6+3.037ml/m2. Though the patients with POAF had larger LA volume, the chi square test analysis did not yield any clinically significant relationship between LAVI and POAF in our study (p=0.3). The mean LA global strain for the patients with POAF was 29.73+3.695%. And for the patients with no POAF was 36.3+4.854%. LA global strain was reduced in patients who developed POAF (P<0.001) which indicated a strong correlation between LA strain and POAF.\n \n \n \n There is significant correlation between Global Left Atrial Strain and POAF in patients undergoing CABG (P<0.001).There is no significant correlation between patient factors like age, BMI, and the conventional coronary risk factors with POAFThere is no significant correlation between the conventional echocardiographic parameters like LA diameter, LAVI, LVDD, LVSD, LVEF and transmitral flow velocities with POAF.\n To conclude, preoperative speckle tracking assessment of LA has a strong predictive role in determining the occurrence of POAF in patients undergoing Coronary artery bypass grafting surgery.\n \n \n \n Type of funding sources: None.\n