# Ryanodine receptor regulation in post-operative atrial fibrillation

> **NIH NIH R01** · BAYLOR COLLEGE OF MEDICINE · 2021 · $540,466

## Abstract

PROJECT SUMMARY / ABSTRACT
Postoperative atrial fibrillation (poAF) is a common complication of cardiothoracic surgery with an incidence
between 10 and 50%. This condition typically peaks on day 2-3 following surgery, and is associated with
excessive hospitalization time, increased risk of stroke, and an increase in patient morbidity. Whereas progress
has been made towards understanding the pathogenesis of AF in general, very little remains known about the
molecular mechanisms underlying poAF. Our preliminary data reveal perturbed intracellular Ca handling in
atrial biopsies from patients with poAF. Increased activity of the ryanodine receptor Ca release channel was
found in atrial myocytes of patients with poAF and a novel mouse model of poAF. Our data suggest that
enhanced RyR2 activity is caused by altered levels of `Striated Muscle Preferentially Expressed Protein
Kinase' (SPEG) in atria of patients and mice with poAF. The long-term goal of this project is to elucidate the
molecular and cellular mechanisms underlying poAF development. We will test the hypothesis that abnormal
Ca release via RyR2 due to altered SPEG phosphorylation causes enhanced susceptibility to poAF.

## Key facts

- **NIH application ID:** 10197997
- **Project number:** 5R01HL089598-12
- **Recipient organization:** BAYLOR COLLEGE OF MEDICINE
- **Principal Investigator:** Xander H.T. Wehrens
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $540,466
- **Award type:** 5
- **Project period:** 2007-08-01 → 2023-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10197997

## Citation

> US National Institutes of Health, RePORTER application 10197997, Ryanodine receptor regulation in post-operative atrial fibrillation (5R01HL089598-12). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10197997. Licensed CC0.

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