Overdrive pacing of early ischemic ventricular tachycardia: evidence for both reentry and triggered activity
Cast your vote
You can rate an item by clicking the amount of stars they wish to award to this item.
When enough users have cast their vote on this item, the average rating will also be shown.
Your vote was cast
Thank you for your feedback
Thank you for your feedback
MetadataShow full item record
CitationAm. J. Physiol. Heart Circ. Physiol. 2005, 288(3):H1124-30
AbstractEntrainment can be a useful method to identify reentry as a mechanism of ventricular tachycardia (VT). In this study, we evaluated the effect of gradually decreasing cycle lengths of overdrive pacing for stable VT induced in a canine model 1-3 h after coronary occlusion. Intact dogs underwent anterior descending coronary artery occlusion after instrumentation of the risk zone with 21 multipolar plunge needles, each recording 6 bipolar electrograms. Overdrive pacing was attempted if the animals had sustained hemodynamically stable VT, looking for evidence of entrainment. Subsequent three-dimensional mapping determined the mechanism of VT. Fifteen of the 21 dogs studied demonstrated entrainment with overdrive pacing by progressive QRS fusion alone (1), the first nonpaced QRS entrained to the paced cycle length only (7), or both (7). Five of these 15 dogs also had postpacing acceleration of the VT at a subsequent faster pacing cycle length. The mechanism of acceleration in four was a change to a VT with a focal origin. The prepacing mechanism in all 15 dogs was subsequently mapped to reentry. Regarding the six VTs, which demonstrated no evidence for entrainment, the site of earliest activity was mapped to a focal origin in all. These data showing entrainment of inducible reentrant VTs and lack of such for focal VTs support that the focal VTs seen in this study are unlikely the result of microreentry but possibly a mechanism as triggered activity.
DescriptionTo access publisher full text version of this article. Please click on the hyperlink in Additional Links field
- Role of the Purkinje system in spontaneous ventricular tachycardia during acute ischemia in a canine model.
- Authors: Arnar DO, Bullinga JR, Martins JB
- Issue date: 1997 Oct 7
- Pharmacological stimulation of cardiac gap junction coupling does not affect ischemia-induced focal ventricular tachycardia or triggered activity in dogs.
- Authors: Xing D, Kjølbye AL, Petersen JS, Martins JB
- Issue date: 2005 Feb
- Triggered activity due to delayed afterdepolarizations in sites of focal origin of ischemic ventricular tachycardia.
- Authors: Xing D, Martins JB
- Issue date: 2004 Nov
- Alpha-2 adrenergic antagonism enhances risk of ventricular tachycardia during acute ischemia.
- Authors: Arnar DO, Xing D, Martins JB
- Issue date: 2007 Dec
- Dose-related shortening of ventricular tachycardia cycle length after administration of the KATP channel opener bimakalim in a 4-day-old chronic infarct anesthetized pig model.
- Authors: Aidonidis I, Poyatzi A, Stamatiou G, Lymberi M, Stamatoyannis N, Molyvdas PA
- Issue date: 2009 Sep