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Giuseppe Oreto - One of the best experts on this subject based on the ideXlab platform.

  • wide complex tachycardia with Atrioventricular Dissociation and qrs morphology identical to that of sinus rhythm a manifestation of bundle branch reentry
    Heart, 1996
    Co-Authors: Giuseppe Oreto, Joep L R M Smeets, Luzmaria Rodriguez, Carl Timmermans, H J J Wellens
    Abstract:

    OBJECTIVE: To determine the features that distinguish bundle branch reentry (BBR) ventricular tachycardia from a supraventricular tachycardia with aberration on the 12 lead electrocardiogram (ECG). PATIENTS: Three patients in whom premature beats (2 cases) or sustained tachycardia (2 cases) showed a QRS configuration identical to that observed during sinus rhythm. INTERVENTIONS: Programmed electrical stimulation. RESULTS: These arrhythmias were ventricular in origin and caused by a BBR mechanism, as suggested by the following data obtained during electrophysiological study: (a) an H-V interval shorter during tachycardia than during sinus rhythm; (b) A-V Dissociation; (c) activation of the right bundle branch before activation of the bundle of His. The ECG of all 3 patients showed right bundle branch block with very prolonged QRS duration (0.16 to 0.20 s). Characteristically, all 3 had prolonged H-V interval during sinus rhythm. All patients had had a previous myocardial infarction and had a dilated left ventricle. CONCLUSION: The presence of (a) wide complex extrasystoles or tachycardia with a QRS morphology identical to that of sinus rhythm; (b) A-V Dissociation; and (c) a very prolonged QRS duration (0.16 s or more) is suggestive of ventricular tachycardia caused by bundle branch reentry.

  • pseudo Atrioventricular Dissociation caused by interpolated ventricular extrasystoles in the presence of dual Atrioventricular nodal pathway
    Chest, 1994
    Co-Authors: Francesco Luzza, Giuseppe Oreto
    Abstract:

    This report describes a patient manifesting with ventricular extrasystoles. The pause occasioned by extrasystoles often is followed by narrow QRS complexes not preceded by P waves, but at times is followed by a sinus P wave. At first glance, the pattern suggests a diagnosis of Atrioventricular (A-V) junctional escape complexes. Analysis reveals that ventricular extrasystoles are, in fact, interpolated; the sinus P wave that follows the extrasystole is conducted to the ventricles with a very prolonged P-R interval (up to 0.80 s). The phenomenon is due to the presence of a dual A-V nodal pathway. The sinus impulse that follows the extrasystole is blocked in the fast pathway but may still be conducted to the ventricles through the slow pathway, resulting in a very prolonged P-R interval.

H J J Wellens - One of the best experts on this subject based on the ideXlab platform.

  • wide complex tachycardia with Atrioventricular Dissociation and qrs morphology identical to that of sinus rhythm a manifestation of bundle branch reentry
    Heart, 1996
    Co-Authors: Giuseppe Oreto, Joep L R M Smeets, Luzmaria Rodriguez, Carl Timmermans, H J J Wellens
    Abstract:

    OBJECTIVE: To determine the features that distinguish bundle branch reentry (BBR) ventricular tachycardia from a supraventricular tachycardia with aberration on the 12 lead electrocardiogram (ECG). PATIENTS: Three patients in whom premature beats (2 cases) or sustained tachycardia (2 cases) showed a QRS configuration identical to that observed during sinus rhythm. INTERVENTIONS: Programmed electrical stimulation. RESULTS: These arrhythmias were ventricular in origin and caused by a BBR mechanism, as suggested by the following data obtained during electrophysiological study: (a) an H-V interval shorter during tachycardia than during sinus rhythm; (b) A-V Dissociation; (c) activation of the right bundle branch before activation of the bundle of His. The ECG of all 3 patients showed right bundle branch block with very prolonged QRS duration (0.16 to 0.20 s). Characteristically, all 3 had prolonged H-V interval during sinus rhythm. All patients had had a previous myocardial infarction and had a dilated left ventricle. CONCLUSION: The presence of (a) wide complex extrasystoles or tachycardia with a QRS morphology identical to that of sinus rhythm; (b) A-V Dissociation; and (c) a very prolonged QRS duration (0.16 s or more) is suggestive of ventricular tachycardia caused by bundle branch reentry.

R A Santilli - One of the best experts on this subject based on the ideXlab platform.

  • isorhythmic Atrioventricular Dissociation in labrador retrievers
    Journal of Veterinary Internal Medicine, 2012
    Co-Authors: M Perego, L Ramera, R A Santilli
    Abstract:

    Background Isorhythmic Atrioventricular Dissociation (IAVD) is a rhythm disturbance in which atria and ventricles are driven by independent pacemakers at equal or nearly equal rates. Objectives To describe electrocardiographic and electrophysiologic features of IAVD in a group of 11 Labrador Retrievers and its possible correlation with focal junctional tachycardia (FJT). Animals Between December 2004 and October 2010, medical records of 11 Labrador Retrievers with surface electrocardiographic findings compatible with IAVD were retrospectively analyzed. Methods Twelve-lead surface electrocardiograms, thoracic radiographs, and echocardiographic findings of each dog and electrophysiologic mapping results of 3 dogs were retrospectively analyzed. Results In 10 of 11 dogs, the ECG pattern revealed the presence of IAVD with type I synchronization. In 5 of 10 dogs, IAVD with type I synchronization was interrupted by periods of junctional tachycardia with 1 : 1 ventriculo-atrial conduction. One of 11 dogs presented IAVD with type II synchronization. The ECG diagnosis of IAVD with type I and type II synchronization, and junctional rhythm with 1 : 1 ventriculo-atrial conduction was confirmed in 3 of 11 dogs with endocardial mapping in which the diagnosis of focal junctional tachycardia was made. Conclusion and Clinical Importance IAVD with type I synchronization is more common than IAVD with type II synchronization in Labrador Retrievers, and a correlation between IAVD and FJT can be hypothesized.

Richard Holloway - One of the best experts on this subject based on the ideXlab platform.

  • Atrioventricular Dissociation after Electroconvulsive Therapy
    2013
    Co-Authors: Srikanth Vallurupalli, Jennifer Arnoldi, Richard Holloway
    Abstract:

    License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Electroconvulsive therapy (ECT) is increasingly used as a treatment for psychiatric disorders. Cardiac effects are the principal cause of medical complications in these patients. We report a case of Atrioventricular (AV) Dissociation that occurred after ECT that was treated with pacemaker implantation. The mechanisms contributing to the onset of AV Dissociation in this patient, and the management and rationale for device therapy, in light of the most recent guidelines, are reviewed. 1

  • Atrioventricular Dissociation after electroconvulsive therapy
    Cardiology Research and Practice, 2011
    Co-Authors: Srikanth Vallurupalli, Jennifer Arnoldi, Richard Holloway
    Abstract:

    Electroconvulsive therapy (ECT) is increasingly used as a treatment for psychiatric disorders. Cardiac effects are the principal cause of medical complications in these patients. We report a case of Atrioventricular (AV) Dissociation that occurred after ECT that was treated with pacemaker implantation. The mechanisms contributing to the onset of AV Dissociation in this patient, and the management and rationale for device therapy, in light of the most recent guidelines, are reviewed.

Fred Morady - One of the best experts on this subject based on the ideXlab platform.

  • Wide QRS tachycardia with Atrioventricular Dissociation and an HV interval of 60 msec: what is the tachycardia mechanism?
    Journal of cardiovascular electrophysiology, 1997
    Co-Authors: Frank Bogun, Stefan H. Hohnloser, Fred Morady
    Abstract:

    A 63-year-oId man had an episode of unexplained syncope. He had triple-vessel coronary artery disease, a history of an anterior and inferior myocardial infarction, and had undergone a coronary artery bypass operation 3 years earlier. Cardiac catheterizalion demonstraied a left ventricular ejection fraction of 0.17, and patency of all three saphenous vein grafts. An elecuophysiologic test was perfonned. The baseline sinus cycle length was 760 msec, the QRS duration was 110 msec, and the atriat-His and His-ventricuJar (HV) intervals were 120 and 55 msec, respectively. Sinus node function was normal, and there was no carotid hypetsensitivity, infranodal block during atrial pacing, or evidence ol dual AV nodal physiology. The AV block cycle length was 370 msec. Tachycardia was not inducible by atrial pacing. A wide QRS complex tachycardia having a cycle length of 210 msec was induced by ptogramined ventricular stimulation (Fig. 1). The tachycardia had a left bundle branch block configuration (Fig. 2). When sustained, the tachycardia resulted in severe hypotension and required electrical catdioversion. Sometimes the tachycardia was nonsustained (Fig. 3). What is the tachyciirdia mechanism?