Insights into new-onset atrial fibrillation following open heart surgery and implications for type II atrial flutter.
OBJECTIVE
Postoperative atrial fibrillation (POAF), new-onset AF after open heart surgery (OHS), is thought to be related to pericarditis. Based on AF studies in the canine sterile pericarditis model, we hypothesized that POAF in patients after OHS may be associated with a rapid, regular rhythm in the left atrium (LA), suggestive of an LA driver maintaining AF. The aim of this study was to test the hypothesis that in patients with POAF, atrial electrograms (AEGs) recorded from at least one of the two carefully selected LA sites would manifest a rapid, regular rhythm with AEGs of short cycle length (CL) and constant morphology, but a selected right atrial (RA) site would manifest AEGs with irregular CLs and variable morphology.


RESULTS
In 44 patients undergoing OHS, AEGs recorded from the epicardial surface of the RA, the LA portion of Bachmann's bundle, and the posterior LA during sustained AF were analysed for regularity of CL and morphology. Sustained AF occurred in 15 of 44 patients. Atrial electrograms were recorded in 11 of 15 patients; 8 of 11 had rapid, regular activation with constant morphology recorded from at least one LA site; no regular AEG sites were present in 3 of 11 patients.


CONCLUSIONS
Atrial electrograms recorded during sustained POAF frequently demonstrated rapid, regular activation in at least one LA site, consistent with a driver maintaining AF.
Department of Medicine, Case Western Reserve University/University Hospitals Case Medical Center, 11100 Euclid Ave, Cleveland, OH 44106, USA.
Shervin A
SA
Sadrpour
Louis Stokes Cleveland VA Medical Center, 10701 East Blvd, Cleveland, OH 44106, USA.
Deepa
D
Srinivasan
Department of Medicine, Case Western Reserve University/University Hospitals Case Medical Center, 11100 Euclid Ave, Cleveland, OH 44106, USA.
Ashish A
AA
Bhimani
Department of Biomedical Engineering, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH 44106, USA.
Seungyup
S
Lee
Department of Biomedical Engineering, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH 44106, USA.
Kyungmoo
K
Ryu
Department of Medicine, Case Western Reserve University/University Hospitals Case Medical Center, 11100 Euclid Ave, Cleveland, OH 44106, USA.
Ivan
I
Cakulev
Department of Biomedical Engineering, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH 44106, USA.
Celeen M
CM
Khrestian
Department of Surgery, Case Western Reserve University/University Hospitals Case Medical Center, 11100 Euclid Ave, Cleveland, OH 44106, USA.
Alan H
AH
Markowitz
Department of Medicine, Case Western Reserve University/University Hospitals Case Medical Center, 11100 Euclid Ave, Cleveland, OH 44106, USA.
Albert L
AL
Waldo
Department of Medicine, Case Western Reserve University/University Hospitals Case Medical Center, 11100 Euclid Ave, Cleveland, OH 44106, USA Louis Stokes Cleveland VA Medical Center, 10701 East Blvd, Cleveland, OH 44106, USA jxs47@case.edu.
Jayakumar
J
Sahadevan
D000200:Action Potentials; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D001282:Atrial Flutter / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D006329:Heart Conduction System / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D013997:Time Factors; D016896:Treatment Outcome
Atrial arrhythmias; Atrial electrograms; Atrial fibrillation