Novel scale for predicting thrombosis of the left atrium and its appendage before catheter ablation or cardioversion in patients with nonvalvular atrial fibrillation or atrial flutter

Aim . To study the potential of predicting thrombosis of the left atrium (LA) and/or LA appendage (LAA) before catheter ablation (CA) or elective cardioversion in patients with nonvalvular atrial fibrillation (NAF) or atrial flutter (AFL) using indicators available in routine practice. Material and methods . In this single-center retrospective study, the medical records of 1994 patients with nAF or AFL for the period 2014-2019 were analyzed, who underwent transesophageal echocardiography before CA or elective CV. LA/LAA thrombus was found in 33 (1,6%) patients. For the comparison group, 167 patients were randomly selected without LA/LAA thrombosis. Demographic, anamnestic, clinical, laboratory data, results of transthoracic echocardiography, as well as the CHA 2 DS 2 -VASc-RAF (CHA 2 DS 2 -VASc plus 2 points for an estimated glomerular filtration rate <56 ml/min/1,73 m 2 , 4 points for persistent AF (lasting >7 days), 10 points for persistent AF). Results . The mean age of the patients was 60,3±10,9 years (men, 55%). There were more patients with NAF (87,5%), hospitalized for CV (84,0%). Multivariate analysis revealed that the severity of symptoms associated with arrhythmia was associated with the detection of a LA/LAA thrombus (odds ratio (OR) for EHRA class 3-4 14,29 at 95% confidence interval (CI): 3,3-61,8; p<0,0001), left ventricular ejection fraction <48% (OR, 7,83; 95% CI: 1,2-53,05; p=0,035) and total CHA 2 DS 2 -VASc-RAF score (OR, 1,29 at 95% CI: 1,08-1,5; p=0,004). Sup­ple­mentation of the CHA2DS2-VASc-RAF with new independent predictors of LA/LAA thrombosis did not lead to a significant increase in the area under the characteristic curve, which was 0,83 (95% CI: 0,76-0,91) and 0,87 (95% CI: 0,80-0,94), respectively (p=0,13). The OR of LA/LAA thrombosis with a total score CHA 2 DS 2 -VASc-RAF >3 was 12,8 (95% CI: 3,8-43,9; p<0,0001), while the sensitivity, specificity, positive and negative predictive value — 90,6, 57,1, 30,2 and 96,7% respectively. The OR of thrombosis of LA/LAA with a CHA 2 DS 2 -VASc-RAF score >8 was 25,8 (95% CI: 5,9-112,3; p<0,0001), while sensitivity, specificity, positive and negative predictive value — 93,5, 64,0, 34,9 and 97,9%, respectively. Conclusion . When predicting LA/LAA thrombosis, detected during transesophageal echocardiography before CA or elective CV in patients with NAF or AFL who did not have a pronounced structural heart pathology and severe concomitant diseases, taking into account the severity of symptoms associated with arrhythmia and a reduced left ventricular ejection fraction (<48%) in addition to the risk stratification scale for LA/LAA thrombosis CHA 2 DS 2 -VASc-RAF did not lead to an increase in the area under the characteristic curve, but made it possible to increase the OR of LA/LAA thrombosis detection by 2 times and increase the sensitivity, specificity, positive and negative predictive value.