Circulating intermediate monocytes and toll-like receptor 4 correlate with low-voltage zones in atrial fibrillation.
Inflammation has been suggested to play a key role in the pathogenesis of atrial fibrillation (AF). Our hypothesis was that this inflammation, mediated by intermediate monocytes and toll-like receptor 4 (TLR4), causes the formation and expansion of low-voltage zones (LVZs). Prior to ablation, the monocyte subsets of 78 AF patients and TLR4 expression of 66 AF patients were analyzed via a flow cytometric analysis. Based on the CD14/CD16 expression, the monocytes were divided into three subsets: classical, intermediate, and non-classical. At the beginning of the ablation session, voltage mapping was performed. LVZs were defined as all bipolar electrogram amplitudes of < 0.5 mV. Correlations between the flow cytometric analysis results and presence of LVZs, as well as the total area of the LVZ, were examined. Patients with LVZs clearly had a higher proportion of intermediate monocytes (10.0 +- 3.6% vs. 7.2 +- 2.7%, p < 0.001) than those without LVZs. TLR4 was much more frequently expressed in the intermediate monocytes than other two monocyte subsets (p < 0.001). Moreover, the TLR4 expression level in intermediate monocytes correlated positively with the total area of the LVZs (r = 0.267, p = 0.030), especially in patients with paroxysmal AF (r = 0.365, p = 0.015). The intermediate monocytes and TLR4 expression positively correlated with LVZs in AF patients.
|Authors:||Suehiro H, Fukuzawa K, Yoshida N, Kiuchi K, Takami M, Akita T, Tabata T, Takemoto M, Sakai J, Nakamura T, Yatomi A, Takahara H, Sonoda Y, Nakasone K, Yamamoto K, Suzuki A, Yamashita T, Hirata KI,|
|Journal:||Heart Vessels; 2020 Dec;35(12):1717-1726. doi:10.1007/s00380-020-01647-4|
|PubMed:||PMID: 32524234 (Go to PubMed)|