Left versus right atrial difference in dominant frequency, K+ channel transcripts, and fibrosis in patients developing atrial fibrillation after cardiac surgery

Abstract

Background-Atrial fibrillation (AF) developing after cardiac surgery is associated with adverse outcomes; however, the mechanism(s) that trigger and maintain AF in these patients are unknown.

Atrial Fibrillation Initiated by Early Afterdepolarization-Mediated Triggered Activity during Acute Oxidative Stress: Efficacy of Late Sodium Current Blockade

“…Recent clinical studies showed that POAF originated from the LA and not from the pulmonary veins (PVs) [36,37] as in the present study. Furthermore it was shown in post-surgical patients manifesting increased atrial tissue fibrosis (confirmed by biopsies) facilitated the emergence LA foci (“sources”) leading to AF [6,25]. That indeed the EAD-mediated triggered activity is the final path to AF initiation is emphasized by suppressing the AF by the selective block of the I Na-L with GS-967 a powerful and selective inhibitor of EADs.…”

“…Increased systemic and atrial myocardial oxidative stress is often observed in post-operative patients with new onset (acute) paroxysmal AF (POAF) [3,4] with an incidence of up to 50% [5]. Diverse etiological factors such as fibrosis [6,7] and increased Ca 2+ /calmodulin-dependent protein kinase II (CaMKII) activity [8,9] among others, are thought to play a key role in the initiation of oxidative AF [4,10]. While the causative and signaling factors of oxidative AF are reasonably well identified, the mechanism of spontaneous initiation (i.e., not induced by electrical stimulation) of acute oxidative AF in experimental and human studies, remains undefined [10].…”

Functional role of mechanosensitive ion channel Piezo1 in human periodontal ligament cells

“…The 2 2DDCt method was used for analysis of gene expression, as described in other studies. 21,22 Briefly, equation DCt was Ct of each target gene transcript 2 Ct of Gapdh, and DDCt was calculated using the following formula: DDCt 5 DCt [target gene in experiment group] 2 DCt [target gene in control group], then the relative fold difference was calculated using the formula 2 2DDCt .…”

Right Atrial Volume Calculated by Multi-detector Computed Tomography: Useful Predictor of Atrial Fibrillation Recurrence after Pulmonary Vein Catheter Ablation

“…Recently, we reported the signi cance of sympathetic nervous system abnormality for predicting perpetuated AF in patients with paroxysmal AF 23 , and the magnitude of nerve sprouting and hyperinnervation has been reported to be higher in the RA than in the LA in a canine model of AF produced by prolonged RA pacing, further suggesting the signi cance of RA 24 . The percentage area occupied by brosis was also recently shown to be higher in the LA than in the RA of patients who developed AF, suggesting more reversible and quick changes to the right atrium 25 . Our result thus con rms that RA volume is important for morbidity in patients with AF.…”