Endothelin system and atrial fibrillation post-cardiac surgery.
OBJECTIVE
We investigated the relation between the endothelin system and atrial fibrillation.


BACKGROUND
Endothelin has been implicated in the pathophysiology of atrial fibrillation, but the exact role of A- and B-receptors is unknown.


METHODS
We obtained right atrial biopsies from patients in sinus rhythm and preserved left ventricular function, undergoing off-pump coronary artery bypass grafting. The expression of endothelin, A- and B-receptors was measured using real time reverse-transcribed polymerase chain reaction.


RESULTS
We studied 52 patients (45 male, mean age 66+/-1 years, mean ejection fraction 52+/-1%). During a 5-day post-operative period, persistent atrial fibrillation occurred in 15 patients (28.8%). Endothelin mRNA expression was comparable in patients who subsequently developed atrial fibrillation and in those maintaining sinus rhythm. However, the former group displayed down-regulation of endothelin A- (by approximately 60%, p=0.0059) and of B-receptors (by approximately 40%, p=0.0084). The decreased endothelin A-receptor expression could predict atrial fibrillation occurrence (Wilks lambda=0.86, F=6.16, p=0.017).


CONCLUSIONS
Decreased endothelin A- and B-receptor expression is associated with atrial fibrillation after bypass surgery.
Kolettis
Theofilos M
TM
Department of Cardiology, University of Ioannina, Ioannina, Greece.
Kyriakides
Zenon S
ZS
Zygalaki
Eleni
E
Kyrzopoulos
Stamatis
S
Kaklamanis
Loukas
L
Nikolaou
Nikolaos
N
Lianidou
Evi S
ES
Kremastinos
Dimitrios Th
DT
D000368:Aged; D001281:Atrial Fibrillation / Q000503:physiopathology*; D001706:Biopsy; D016009:Chi-Square Distribution; D047549:Coronary Artery Bypass, Off-Pump; D016232:Endothelins / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D012333:RNA, Messenger / Q000378:metabolism; D012372:ROC Curve; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric
D016232:Endothelins; D012333:RNA, Messenger