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Geoffrey Lee,
Steven Spence,
Andrew Teh,
John Goldblatt,
Marco Larobina, Victoria Atkinson,
Robin Brown,
Joseph B Morton,
Prashanthan Sanders,
Peter M Kistler,
Jonathan M Kalman
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ABSTRACT: The pulmonary veins (PVs) and the PV-LA (left atrium) junction are established sources of triggers initiating atrial fibrillation. In addition, they have been implicated in the maintenance of arrhythmia.
To undertake high-density electrophysiological characterization of the right superior PV-LA junction in humans.
Mapping was performed in 18 patients without a history of atrial fibrillation undergoing cardiac surgery. A high-density epicardial plaque was positioned at the anterior right superior pulmonary vein covering 3 regions: LA, PV-LA junction, and the PV. Isochronal maps were created during (1) sinus rhythm (SR); (2) LA pacing (LA-Pace); (3) PV pacing (PV-Pace); (4) LA programmed electrical stimulation (LA-PES); and (5) PV programmed electrical stimulation (PV-PES). Regional differences in conduction slowing/conduction block (CS/CB) and the prevalence of fractionated signals (FS) and double potentials (DPs) were assessed.
A region of isochronal crowding representing CS/CB developed at the PV-LA junction in 84% of the maps. Three distinct activation patterns were seen. Pattern 1: Uniform SR activation without CS/CB. LA-Pace and PES caused 1 to 2 lines of isochronal crowding (CS/CB) at the PV-LA junction. Pattern 2: CS/CB occurred at the PV-LA junction in SR. LA/PV-Pace and LA/PV-PES caused an increase in CS/CB at the PV-LA junction with widely split DPs and FS. Pattern 3: A single incomplete line of CS at the PV-LA junction in SR. With LA/PV pacing and LA/PV-PES, multiple lines (≥3) of CS/CB developed at the PV-LA junction with evidence of circuitous activation and a marked increase in DPs and FS.
High-density epicardial mapping of the right superior pulmonary vein demonstrates marked functional conduction delay and circuitous activation patterns at the PV-LA junction, creating the substrate for reentry.
Heart rhythm: the official journal of the Heart Rhythm Society 09/2011; 9(2):258-64. · 4.56 Impact Factor
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The Journal of thoracic and cardiovascular surgery 03/2011; 141(6):e41-2. · 3.41 Impact Factor
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ABSTRACT: Factor XII deficiency is associated with a prolonged activated partial thromboplastin time and activated clotting time used for monitoring during cardiopulmonary bypass. It does not predispose to an increased risk of bleeding. We present the strategy used for a case of coronary artery bypass grafting in a patient with factor XII deficiency, followed by a brief discussion of the important clinical considerations when patients with factor XII deficiency undergo cardiac surgery. Monitoring of heparin and the avoidance of anti-fibrinolytic agents are the main intraoperative issues. Postoperative care must include careful thromboembolic prophylaxis and vigilance against infection.
The Annals of thoracic surgery 02/2010; 89(2):625-6. · 3.74 Impact Factor
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ABSTRACT: Thrombotic cutaneous gangrene is a rare complication of heparin-induced thrombocytopaenia after cardiac surgery. We report a case and discuss management issues with cardiopulmonary bypass for cardiac surgery in this condition.
Heart Lung & Circulation 04/2008; 18(4):307-10. · 1.20 Impact Factor
