Mechanical concordance between left atrium and left atrial appendage in nonvalvular atrial fibrillation: can it be exploited to avoid transesophageal echocardiography prior to electrical cardioversion during Covid‑19 pandemic?

<p>Transesophageal echocardiography (TEE) is the gold standard for assessing left atrial appendage (LAA) mechanic and throm-<br> bosis (LAAT); however, TEE is a high-risk procedure for viral transmission during coronavirus disease 2019 (COVID-19)&nbsp;<br> pandemic. We investigated whether deformation indices of left atrium (LA) at transthoracic echocardiography (TTE) correlate&nbsp;<br> with those of LAA assessed by TEE in nonvalvular atrial fibrillation (NVAF) patients undergoing electrical cardioversion&nbsp;<br> (ECV). Consecutive patients with NVAF of &ge; 48&nbsp;h or unknown duration, who underwent TEE and TTE at our Institution&nbsp;<br> before ECV were retrospectively investigated. Standard echo-Doppler and LA and LAA myocardial strain and strain rate&nbsp;<br> parameters were analyzed. A total of 115 NVAF patients (71.3 &plusmn; 8.1&nbsp;yr/o, 59.1% men) were included: LAAT was diagnosed&nbsp;<br> in 25 (21.7%) patients. Compared to patients without LAAT, those with LAAT had significantly higher &nbsp;CHA2DS2-VASc&nbsp;<br> Risk score (4.5 &plusmn; 1.4 vs. 3.5 &plusmn; 1.1, p &lt; 0.001), and lower ejection fraction (46.0 &plusmn; 14.8 vs. 57.6 &plusmn; 8.6%, p &lt; 0.001). In LAAT&nbsp;<br> patients, global strain of LA (8.7 &plusmn; 2.6 vs. 16.3 &plusmn; 4.5%, p &lt; 0.001) and LAA (7.0 &plusmn; 1.7 vs. 11.7 &plusmn; 2.0%, p &lt; 0.001) was sig-<br> nificantly reduced compared to non-LAAT patients. A close relationship between left atrial strain reservoir (LASr) and&nbsp;<br> LAA-global strain was demonstrated (r = 0.81). By univariable analysis, CHA2DS2-VASc Risk Score (OR 2.01, 95%CI&nbsp;<br> 1.34&ndash;3.00), NT-proBNP (OR 1.36, 95%CI 1.19&ndash;1.54), ejection fraction (OR 0.92, 95%CI 0.88&ndash;0.96), E/e&rsquo; ratio (OR 2.07,&nbsp;<br> 95%CI 1.51&ndash;2.85), and LASr (OR 0.39, 95%CI 0.25&ndash;0.62) were strongly associated with LAAT presence at TEE. By mul-<br> tivariable analysis, only LASr (OR 0.40, 95%CI 0.24&ndash;0.70) retained statistical significance. ROC curve analysis revealed&nbsp;<br> that an LASr cut-off value &le; 9.3% had 98.9% sensibility and 100% specificity to identify LAAT by TEE (AUC = 0.98). In&nbsp;<br> patients with NVAF of &ge; 48&nbsp;h or unknown duration, scheduled to undergo ECV, LA deformation assessment by TTE might&nbsp;<br> substitute invasive measurement of LAA function by TEE, simplifying diagnostic approach and possibly contributing to&nbsp;<br> reduce COVID-19 infection diffusion.</p>