Dataset Information

Analysis of immune cell populations in atrial myocardium of patients with atrial fibrillation or sinus rhythm.

ABSTRACT:

Background

Atrial fibrillation (AF) is the most common arrhythmia and despite obvious clinical importance remains its pathogenesis only partially explained. A relation between inflammation and AF has been suggested by findings of increased inflammatory markers in AF patients.

Objective

The goal of this study was to characterize morphologically and functionally CD45-positive inflammatory cell populations in atrial myocardium of patients with AF as compared to sinus rhythm (SR).

Methods

We examined 46 subjects (19 with AF, and 27 in SR) undergoing coronary bypass or valve surgery. Peroperative bioptic samples of the left and the right atrial tissue were examined using immunohistochemistry.

Results

The number of CD3+ T-lymphocytes and CD68-KP1+ cells were elevated in the left atrial myocardium of patients with AF compared to those in SR. Immune cell infiltration of LA was related to the rhythm, but not to age, body size, LA size, mitral regurgitation grade, type of surgery, systemic markers of inflammation or presence of diabetes or hypertension. Most of CD68-KP1+ cells corresponded to dendritic cell population based on their morphology and immunoreactivity for DC-SIGN. The numbers of mast cells and CD20+ B-lymphocytes did not differ between AF and SR patients. No foci of inflammation were detected in any sample.

Conclusions

An immunohistochemical analysis of samples from patients undergoing open heart surgery showed moderate and site-specific increase of inflammatory cells in the atrial myocardium of patients with AF compared to those in SR, with prevailing population of monocyte-macrophage lineage. These cells and their cytokine products may play a role in atrial remodeling and AF persistence.

SUBMITTER: Smorodinova N

PROVIDER: S-EPMC5321459 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Publications

Analysis of immune cell populations in atrial myocardium of patients with atrial fibrillation or sinus rhythm.

Smorodinova Natalia N Bláha Martin M Melenovský Vojtěch V Rozsívalová Karolína K Přidal Jaromír J Ďurišová Mária M Pirk Jan J Kautzner Josef J Kučera Tomáš T

PloS one 20170222 2

<h4>Background</h4>Atrial fibrillation (AF) is the most common arrhythmia and despite obvious clinical importance remains its pathogenesis only partially explained. A relation between inflammation and AF has been suggested by findings of increased inflammatory markers in AF patients.<h4>Objective</h4>The goal of this study was to characterize morphologically and functionally CD45-positive inflammatory cell populations in atrial myocardium of patients with AF as compared to sinus rhythm (SR).<h4> ...[more]

PMID: 28225836

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Dataset Information

Analysis of immune cell populations in atrial myocardium of patients with atrial fibrillation or sinus rhythm.

Background

Objective

Methods

Results

Conclusions

Publications

Analysis of immune cell populations in atrial myocardium of patients with atrial fibrillation or sinus rhythm.

Similar Datasets

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