Document Detail

Brugada ECG Pattern Unmasked by IV Flecainide in an Individual with Idiopathic Fascicular Ventricular Tachycardia.
Jump to Full Text
MedLine Citation:
PMID:  23329876     Owner:  NLM     Status:  PubMed-not-MEDLINE    
Abstract/OtherAbstract:
A 45-year old man presents with stable monomorphic ventricular tachycardia. He had previously been diagnosed with idiopathic fascicular ventricular tachycardia. Intravenous flecainide results in termination of his tachycardia but unmasks a latent type 1 Brugada ECG pattern not seen on his resting ECG. We discuss his subsequent management and the need to consider an alternative diagnosis in individuals with a Brugada type ECG pattern who present with stable monomorphic ventricular tachycardia.
Authors:
Andrew R Gavin; Glenn D Young; Andrew D McGavigan
Related Documents :
24523326 - J point elevation as a predictor of premature ventricular beats.
18626106 - Utility of store-and-forward pediatric telecardiology evaluation in distinguishing norm...
23419096 - Trans-subclavian approach for radiofrequency ablation of premature ventricular contract...
6770386 - Reappraisal of some problems concerning the genesis of heart sounds.
3086416 - Coronary thrombolysis by intravenous infusion of recombinant single chain urokinase-typ...
433766 - Disopyramide-induced ventricular fibrillation.
Publication Detail:
Type:  Journal Article     Date:  2013-01-01
Journal Detail:
Title:  Indian pacing and electrophysiology journal     Volume:  13     ISSN:  0972-6292     ISO Abbreviation:  Indian Pacing Electrophysiol J     Publication Date:  2013 Jan 
Date Detail:
Created Date:  2013-01-18     Completed Date:  2013-01-21     Revised Date:  2013-05-30    
Medline Journal Info:
Nlm Unique ID:  101157207     Medline TA:  Indian Pacing Electrophysiol J     Country:  India    
Other Details:
Languages:  eng     Pagination:  52-5     Citation Subset:  -    
Affiliation:
Department of Cardiovascular Medicine, Flinders Medical Centre.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Comments/Corrections

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Full Text
Journal Information
Journal ID (nlm-ta): Indian Pacing Electrophysiol J
Journal ID (iso-abbrev): Indian Pacing Electrophysiol J
Journal ID (publisher-id): Indian Pacing Electrophysiol J
ISSN: 0972-6292
Publisher: Indian Heart Rhythm Society
Article Information
Download PDF
Copyright: © 2013 Gavin et al.
open-access:
collection publication date: Season: Jan-Feb Year: 2013
Electronic publication date: Day: 01 Month: 1 Year: 2013
Volume: 13 Issue: 1
First Page: 52 Last Page: 55
PubMed Id: 23329876
ID: 3539402
Publisher Id: ipej130052-00

Brugada ECG Pattern Unmasked by IV Flecainide in an Individual with Idiopathic Fascicular Ventricular Tachycardia
Andrew R Gavin, MBChB1
Glenn D Young, MBBS, FRACP2
Andrew D McGavigan, MD13
1Department of Cardiovascular Medicine, Flinders Medical Centre
2Department of Medicine, University of Adelaide
3Faculty of Medicine, Flinders University of South Australia
Correspondence: Address for correspondence: A/Prof Andrew McGavigan, Director of Pacing and Electrophysiology, Flinders Medical Centre, Bedford Park, South Australia 5042, Australia.Andrew.McGavigan@health.sa.gov.au

Case Report

A 45-year old man presented with sudden onset palpitations whilst exercising. There was no associated hemodynamic compromise. Electrocardiogram (ECG) showed monomorphic ventricular tachycardia (VT) with a right bundle branch block pattern and a superior axis (Figure 1A).

He gave a history of 3 prior episodes over the preceding 20 years and had seen an electrophysiologist previously. There was no history of syncope and no family history of sudden cardiac death. Resting ECG was within normal limits (Figure 1B) and echocardiography demonstrated a structurally normal heart. At that time, a diagnosis of idiopathic fascicular VT was made and after discussion the patient elected not to undergo an electrophysiology study (EPS).

On this occasion he was treated in the Emergency Department with IV flecainide at the instruction of his treating electrophysiologist. This resulted in termination of tachycardia with restoration of sinus rhythm but unmasked a latent type 1 Brugada ECG pattern (Figure 1C), not seen on his resting ECG (Figure 1B). In view of his history of ventricular arrhythmia and a type I Brugada ECG pattern he was referred by the admitting team for consideration for an implantable defibrillator (ICD).

However, following discussion with the electrophysiology service, a diagnostic EPS with a view to ablation of his idiopathic fascicular VT was recommended. Following administration of intravenous isoproterenol, monomorphic VT (CL 260ms) was easily induced on multiple occasions with programmed ventricular stimulation. This VT had an identical morphology to that seen on arrival at the Emergency Department. An externally irrigated ablation catheter (Cool Path Duo, St Jude Medical, St Paul, MN, USA) was advanced retrogradely to the left ventricle and a 3 dimensional (3D) left ventricular geometry and activation map was created using Ensite Velocity (St Jude Medical, St Paul, MN, USA) (Figure 2).

Earliest activation of the ventricle was seen at the insertion of the posterior fascicle with centrifugal activation of the rest of the chamber. The catheter was drawn back along the inferior septum to the region of the posterior fascicle until a discrete Purkinje potential could be identified preceding each ventricular electrogram (Figure 1D). Ablation was performed (maximum 40W) in the region of the posterior fascicle (Figure 2). Following ablation no polymorphic or monomorphic VT or ventricular fibrillation was inducible with programmed stimulation and up to 3 extra beats either in the baseline state or with isoproterenol.


Discussion

We present a case of monomorphic VT in a patient with a type 1 Brugada ECG pattern following injection of intravenous flecainide. This raises the possibility of either monomorphic VT as part of the Brugada syndrome or of a latent Brugada ECG pattern in an individual with idiopathic fascicular VT. The common form of idiopathic fascicular VT is characterized by a relatively narrow QRS width with right bundle branch block morphology and a superior axis [1]. It commonly presents in the second to fourth decade, is usually paroxysmal and is associated with a structurally normal heart. It is commoner in males and has a good prognosis. It can be induced by exercise, atrial and ventricular premature beats and atrial and ventricular pacing, and can be terminated using verapamil. The tachycardia is thought to be due to a reentrant circuit close to the posterior fascicle of the left bundle branch. In this case the administration of intravenous flecainide presumably slowed a critical part of the circuit sufficiently to produce block thereby resulting in termination of the tachycardia and restoration of sinus rhythm. At EPS, high frequency Purkinje potentials are seen preceding the site of earliest ventricular activation during VT. Catheter ablation is the preferred treatment choice for fascicular VT with a success rate of greater than 90%.

Brugada syndrome was first described in 1992 and is characterized by episodes of syncope or unexpected sudden death in patients with structurally normal hearts [2]. It classically presents with polymorphic VT/VF. Whilst a Brugada ECG refers to the manifestation of a type 1 ST-segment elevation, Brugada syndrome is only definitively diagnosed when these changes are observed in conjunction with one or more of the following: documented VF, polymorphic VT, a family history of sudden cardiac death below 45 years of age, coved-type ECG changes in family members, inducibility of polymorphic VT with programmed electrical stimulation, syncope or nocturnal agonal respiration [3].

In this case although he undoubtedly has a type 1 Brugada ECG pattern he has no other features to indicate he has Brugada syndrome. The ease of inducibility of VT, the intra-cardiac EGMs, the activation map and the site of successful ablation all support a diagnosis of idiopathic fascicular VT as the likely cause for his tachycardia.

While monomorphic VT has previously been reported in individuals with Brugada Syndrome [4] it is extremely rare. An ICD in this gentleman would have been inappropriate putting him a risk of potential defibrillation, with its associated morbidity and mortality risks, for non-life threatening arrhythmias.

This case highlights the importance of excluding other, potentially treatable causes of idiopathic VT prior to ICD implantation. This is especially true in those with a Brugada type ECG pattern who are considered at low risk of sudden cardiac death, where appropriate ablative strategies can negate the need for a defibrillator.


References
Ramprakash B,et al. Catheter ablation of fascicular ventricular tachycardiaIndian Pacing Electrophysiol JYear: 2008193202
Brugada P,et al. Right bundle branch block, a persistent ST segment elevation and sudden cardiac death: a distinct clinical and electrocardiographic syndrome. A multicenter reportJ Am Coll CardiolYear: 19922013911309182
Antzelevitch C. Brugada SyndromePacing Clin ElectrophysiolYear: 200629113017038146
Shimada M,et al. Sustained Monomorphic Ventricular Tachycardia in a Patient With Brugada SyndromeJpn Circ JYear: 1996603648844303

Article Categories:
  • Case Report

Keywords: monomorphic ventricular tachycardia, Brugada, fascicular, idiopathic.

Previous Document:  Atrioventricular Nodal Re-entry Tachycardia in Identical Twins: A Case Report and Literature Review.
Next Document:  Adult-Directed and Peer-Directed Respect for Authority: Relationships With Aggressive and Manipulati...