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

Abstract

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 CHA2DS2-VASc-RAF (CHA2DS2-VASc plus 2 points for an estimated glomerular filtration rate <56 ml/min/1,73 m2, 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 CHA2DS2-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 CHA2DS2-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 CHA2DS2-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 CHA2DS2-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.