Abstract 12602: Local NET Burden is Associated With Biomarkers of Thrombosis and Cardiac Damage in Left Atrial Cardiopathy

• Published in: Circulation (New York, N.Y.) N.Y.), 2021-11, Vol.144 (Suppl_1), p.A12602-A12602
• Main Authors: Martinod, Kimberly, Claessen, Annika, Martens, Caroline P, Krauel, Krystin, Pereira Velàsquez, Leydi Carolina, Witsch, Thilo
• Format: Article
• Language: English
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/circ.144.suppl_1.12602

Atrial cardiopathy results in disturbed blood flow, providing an ideal thrombogenic environment. Neutrophils promote large vessel occlusions and microthrombosis via release of neutrophil extracellular traps (NETs) and thus lie at the interface of (sterile) inflammation, thrombosis, and fibrosis. We profiled NETs, cytokines, thrombotic factors, and cardiac damage markers in left atrial (LA) cardiopathies together with LA structural analysis. A total of 71 patients (median age 66, 46.5% male) undergoing catheterization procedures with atrial transseptal access at the Freiburg Heart Center were enrolled in this prospective study. Paired samples were collected from peripheral blood draws or from within the left atrium (LA). NET biomarkers, sP-selectin, PAD4, proinflammatory cytokines, thrombotic factors (D-dimers, VWF, ADAMTS13), and cardiac damage markers (TropT, proBNP, ICTP) were measured in plasma or serum as appropriate. Echocardiography was performed to assess LA structure and left ventricular function. Data were analyzed by the type of procedure (MitraClip (MC), left atrial appendage closure (LAAC), pulmonary vein ablation (PVA), or patent foramen ovale closure (PFOC), and by atrial fibrillation (Afib) status at time of procedure. NETs, but not other markers, were elevated in local LA samples as compared to peripheral blood. Conversely, most thrombotic, inflammatory, and cardiac damage markers, but not NETs, were elevated in MC or LAAC as compared to PFOC or PVA patients. Across all patients, NET biomarkers positively correlated with IL-6/TNF-α, VWF, and cardiac damage biomarkers. PAD4/NETs negatively correlated with ADAMTS13 activity, indicating that citrullination may contribute to the prothrombotic phenotype of these patients. Afib was not key to these observations. NETs are locally elevated within the left atrium, with elevation of thrombosis markers including VWF in patients with a diseased left atrium. These elevations partly correlate with structural changes of the left atrium and, therefore, may point toward a disturbed local blood flow. This may provide insight on mechanisms that drive detrimental left atrial remodeling as well as clues regarding thromboembolic risks that are rooted in LA changes rather than Afib.