Celeen M. Khrestian

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BACKGROUND Chronic atrial fibrillation (AF) is thought to be due to multiple, simultaneously circulating wavelets. In the canine sterile pericarditis model, the mechanisms of maintenance of AF are not yet understood. METHODS AND RESULTS During six induced AF episodes in six dogs with sterile pericarditis, 372 unipolar electrograms were recorded(More)
INTRODUCTION We tested the hypothesis that AZD7009 terminates induced atrial fibrillation (AF) and flutter (AFL) and prevents their reinduction, and that effects on refractoriness, conduction, and excitability are predominantly on the atria. METHODS AND RESULTS Thirty-eight electrophysiologic studies were performed during AZD7009 infusion in 11 dogs with(More)
INTRODUCTION Different analysis techniques have been developed to help understand and characterize the mechanisms responsible for atrial arrhythmias. We tested the hypothesis that Fast Fourier Transform (FFT) analysis of recorded atrial electrograms (AEGs) will rapidly and accurately identify regular and irregular patterns of atrial activation, and,(More)
BACKGROUND Vanoxerine produces potent block of cardiac hERG, sodium, and L-type calcium channels. Block is strongly frequency dependent, is unassociated with transmural dispersion of repolarization, and occurs at concentrations safe in humans. Therefore, we proposed that vanoxerine might be antiarrhythmic. In these studies, we tested the hypothesis that(More)
INTRODUCTION Dogs with rapid ventricular pacing (RVP)-induced congestive heart failure (CHF) have inducible atrial tachycardia, flutter, and fibrillation (AF). We tested the hypothesis that rapid atrial activation in multiple regions and at different rates is responsible for sustained AF in this CHF model. METHODS AND RESULTS We studied 12 episodes of(More)
The canine sterile pericarditis model is characterized by impaired conduction and atrial arrhythmia vulnerability. Electrical and structural remodeling processes caused by the inflammatory response likely promote these abnormalities. In the present study, we tested the hypothesis that altered distribution of atrial connexins is associated with markedly(More)
BACKGROUND The mechanisms of chronic atrial fibrillation (AF) are not well understood. We performed epicardial mapping of chronic AF in patients undergoing open heart surgery to test the hypothesis that chronic AF is due to a left atrial "driver" with a regular, short cycle length, resulting in fibrillatory conduction to the rest of the atria. METHODS AND(More)
A line of block between the vena cava and the crista terminalis (CT) region is important for atrial flutter (AFL), but whether it is fixed or functional is controversial. To test the hypothesis that conduction across the CT normally occurs, but when block occurs in this region it is functional, we analyzed atrial activation during right and left atrial(More)
BACKGROUND Atrial fibrillation (AF) and atrial flutter (AFL) are common following cardiac surgery and are associated with significant morbidity. We tested the hypothesis that suppression of the inflammatory response with steroids would significantly modify the inducibility of postoperative AF/AFL in the canine sterile pericarditis model. METHODS(More)
INTRODUCTION Moe et al. hypothesized that multiple wavelets (random reentry) were the mechanism of atrial fibrillation (AF) based on studies in a vagal nerve stimulation (VNS) canine model and a computer model of AF, but atrial mapping during AF in this model has not been done. We restudied this model using high density, simultaneous site mapping to test(More)