Diagnosis Of Wide Complex Tachycardia Research Articles

Aberrancy masquerading as ventricular tachycardia: Importance of invasive electrophysiology study for diagnosis of wide complex tachycardias

BackgroundDifferentiation between ventricular tachycardia (VT) and supraventricular tachycardia (SVT) with aberrancy based on the 12‑lead ECG alone can be imprecise. Implantable cardiac defibrillators (ICD) may be inserted for presumed VT, particularly in patients with syncopal presentation or atypical aberrancy patterns. Accurate diagnosis of these patients facilitated by an electrophysiology study (EPS) may alter diagnosis and management. MethodsWe present a prospective collection of cases across 3 cardiac centers of consecutive patients with WCT presumed to be VT who were referred for consideration of an ICD, and in whom further evaluation including an EPS ultimately demonstrated SVT with aberrancy as the culprit arrhythmia. Results22 patients were identified (17 male, mean age 50±13 years. Available rhythm data at the time of referral was presumptively diagnosed as monomorphic VT in 16 patients and polymorphic VT in 6 patients. Underlying structural heart disease was present in 20 (91%). EPS resulted in a diagnosis of SVT with aberrancy in all cases: comprising AV nodal re-entry tachycardia (n=10), orthodromic reciprocating tachycardia (n=3), focal atrial tachycardia (n=3), AF/AFL (n=3) and 'double fire' tachycardia (n=2). 21 (95%) patients underwent successful ablation. All patients remained free of arrhythmia recurrence at a median of 3.4 years of follow-up. ICD insertion was obviated in 18 (82%) patients, with 1 patient proceeding to ICD extraction. ConclusionSVT with atypical aberrancy may mimic monomorphic or polymorphic VT. Careful examination of all available rhythm data and consideration of an EPS can confirm SVT and obviate the need for ICD therapy.

678 WIDE COMPLEX TACHYCARDIA IN A PATIENT TREATED WITH PERMANENT HIS BUNDLE PACING: A CASE REPORT

Abstract Introduction Differential diagnosis of wide complex tachycardias based only on ECG analysis remains a challenging exercise. But, when intracardiac tracings are available (i.e., pacemaker EGM), electrophysiologists may consider several tricks to make a correct diagnosis. Case Presentation A 73-years-old sporty male was admitted to our hospital for palpitations and dizziness. ECG monitoring revealed AF, typical atrial flutter and asystolic pauses following spontaneous cardioversion of atrial arrhythmias. We diagnosed sick sinus syndrome and implanted a dual-chamber pacemaker with an atrial lead in the right appendage and a stylet-directed active fixation lead in the His region, obtaining non-selective narrow paced QRS. The day after PM implantation, during a new episode of AF, two runs of regular wide-complex tachycardia (LBBB morphology, cycle length of 270 ms) occurred (Fig 1A, B). LBBB morphology, patient's history, and AF favored aberrancy, but couldn't exclude VT or preexcitation (by atrio-fascicular AP). Our diagnostic strategy consisted in adding atrial and His intracardiac electrograms registered by pacemaker to analysis of ECG traces. The device interrogation showed AV dissociation at the time of the wide complex tachyarrhythmia and a negative HV interval (Fig. 2A). These findings ruled out aberrant ventricular conduction and bundle branch reentrant tachycardia, because both these arrhythmias are characterized by HV ≥ HV in sinus rhythm. We performed incremental atrial pacing maneuver, during SR, obtaining decremental AH conduction with constant HV interval (60 ms), excluding atrio-fascicular, nodo-fascicular and nodo-ventricular AP. His bundle activity was identified just after the ventricular activation, producing a relatively short VH interval, suggesting the presence of a retrograde activation of the His bundle, therefore it was possible to hypothesize that the site of origin of the ventricular arrhythmia was within/or very close to RBB (Fig 2B, C). Just in few beats His bundle deflection was missing, probably because of recovery of functional LBBB (Fig 2D). Discussion Our final diagnosis was RBB VT. Patient was treated with Verapamil 80 mg t.i.d., with no further recurrence. This case highlights the diagnostic value of device interrogation in patients with permanent His bundle pacing, for the evaluation of wide complex tachycardias.

A Peculiar Wide Complex Tachycardia During Flecainide Treatment.

A Peculiar Wide Complex Tachycardia During Flecainide Treatment.

Wide Complex Tachycardia in Patient With Cardiac Device

Electrocardiographic clues for a differential diagnosis of wide complex tachycardia in a patient with a pacemaker are presented. (Level of Difficulty: Intermediate.)

Wide Complex Tachycardia and Flecainide: A Dangerous Couple

Differential diagnosis of wide complex tachycardia in patients taking anti-arrhythmic can be challenging. Conventional ECG diagnostic criteria are poorly specific and should be applied with caution. Patients who develop life-threatening arrhythmias after flecainide infusion should be screened for Brugada Syndrome, especially if concomitant sinus node dysfunction is present. (Level of Difficulty: Intermediate.)

Novel criterion for the differential diagnosis of wide QRS complexes and wide complex tachycardia using the initial activation of QRS on leads V1 and V2: Differential diagnosis of wide QRS based on V1-V2

BackgroundMany diagnostic criteria for the differential diagnosis of wide complex tachycardia (WCT) are complex and not completely accurate. Incorrect diagnosis is also related to error in applying criteria. ObjectivesTo propose a novel reliable criterion for wide QRS complexes' differential diagnosis. Material and methodsOne hundred Electrocardiograms (ECGs) with wide QRS complexes were analyzed using the ECG software. Five variables were measured during the first 20 ms of QRS in leads V1 and V2 and compared between premature ventricular contraction (PVC) and conducted supraventricular impulse with bundle branch block (BBB) groups. The best discriminant variable was identified. The validity of this variable was tested on a group of 20 patients who had WCT during an electrophysiology study. ResultsAlmost all variables were statistically different between PVC and BBB groups. The sum of voltages in absolute value of vectors during the initial 20 ms of the QRS in leads V1 and V2 (ΣV1 + V2) was the most discriminant between the two groups (131 ± 85 microvolt [μV] vs. 498 ± 392 μV, p < 0.01). A ΣV1 + V2 < 258 μV (rounded to <0.25 millivolt [mV]) diagnosed PVCs with good sensitivity and specificity (90% and 85% respectively). The ΣV1 + V2 in WCT group had lower values in VT versus supra-ventricular tachycardia (SVT) group (0.53 ± 0.35 mV vs. 1.79 ± 1.04 mV, p = 0.004). ConclusionsThe ΣV1 + V2 < 258 μV is a reliable criterion for PVC diagnosis. It could be measured accurately using ECG Software, which could be programmed to calculate it automatically, limiting the risk of human error. The ΣV1 + V2 also seems capable of discriminating between VT and SVT.

Wide complex tachycardia discrimination using dynamic time warping of ECG beats

Background and objective: Automatic processing and accurate diagnosis of wide complex tachycardia (WCT) arrhythmia groups using electrocardiogram signals (ECG) remains a challenge. WCT arrhythmia consists of two main groups: ventricular tachycardia (VT) and supraventricular tachycardia with aberrancy (SVT-A). These two groups have similar morphologies in the realm of ECG signals. VT and SVT-A arrhythmias originate from the ventricle and atrium, respectively. Hence, inaccurate diagnosis of SVT-A instead of VT can be fatal.Methods: In this paper, we present a novel algorithm using dynamic time warping (DTW) to discriminate between VT and SVT-A arrhythmias. This method includes pre-processing, best template search (BTS), and classifier modules. The first module, pre-processing, is responsible for filtering, R-wave detection, and beat detection of ECG signals. The second module, BTS, automatically extracts the minimum possible number of signals as a template from the entire training dataset using an intelligent algorithm. These template signals have the greatest morphological difference, which leads to accurate WCT discrimination. Finally, a 1NN classifier categorizes the test data using DTW distance.Results: Our proposed method was evaluated on an ECG signal database consisting of 171 subjects. The results showed that the proposed algorithm can accurately discriminate between VT, SVT-A, and normal subjects, and appears to be suitable for future use in clinical application. The obtained accuracy, sensitivity, specificity, and positive predictive values were 93.22%, 88.68%, 96.98%, and 90.27%, respectively.Conclusion: The presented diagnostic method for discriminating VT and SVT-A, using only one ECG lead, is suitable for future clinical use. It can reduce needless therapeutic interventions and minimize risk for patients.

Ventrikuläre Herzrhythmusstörungen

Ventricular arrhythmias include awide range of potentially benign single ventricular premature contractions to ventricular tachycardia and ventricular fibrillation with arisk for sudden cardiac death. The diagnosis of ventricular arrhythmia is made by 12-lead electrocardiogram, 24 h Holter monitoring, an external or implantable loop recorder, or during in-hospital monitoring. Especially the diagnosis of wide complex tachycardias is challenging in terms of differentiating between ventricular tachycardia and supraventricular tachycardia with aberrant atrioventricular conduction. After documentation of ventricular arrhythmias, diagnostic work-up with respect to structural or electrical cardiomyopathy is mandatory followed by risk stratification for sudden cardiac death. Therapeutic options for treatment of ventricular arrhythmias range from pharmacological therapy and interventional procedures such as catheter ablation and implantable devices. The current article provides an overview of the diagnosis of ventricular tachycardia and underlying cardiomyopathies. Furthermore, medical and interventional therapies are described. In addition, the indications for implantable and wearable defibrillators are presented.

24. Entrainment of wide complex tachycardia by atrial stimulation is highly accurate and can rapidly elucidate the tachycardia mechanism through analysis of entrainment response

Although the diagnosis of wide-complex tachycardia (WCT) in the Electrophysiology Laboratory is usually straightforward, occasionally a WCT with 1:1 AV relationship can pose a diagnostic challenge. Furthermore, different responses to entrainment have been reported in relation to the pacing site of a variety of tachycardias, however, transient atrial entrainment of WCT has not been investigated sufficiently and systematically .We studied the response to atrial overdrive pacing to clarify the tachycardia mechanism. Out of 43 consecutive patients who underwent catheter ablation for WCT, we prospectively studied 28 patients (65%, mean age 33 ± 11 years) with WCT and 1:1 AV relationship in whom response to atrial overdrive pacing could be evaluated. During the tachycardia, atrial overdrive pacing was performed. The following responses were observed: A change of the QRS morphology during atrial pacing. The first return electrogram of the tachycardia, whether occurring in the atrium (AVA response) or in the ventricle (AVVA response). Atrial post-pacing interval (PPI) measured to the return A at the pacing site. The difference between PPI and tachycardia cycle length (PPI-TCL). Atrial overdrive pacing was successfully performed in 28 patients. It was associated with either a change or narrowing of the QRS in all ventricular tachycardia (VT, n = 7) patients but not in supraventricular tachycardia (SVT, n = 21) patients. All VT patients had an AVVA response upon cessation of atrial overdrive pacing as opposed to AVA response in SVT patients, p < 0.001. PPI and PPI-TCL were significantly longer in VT patients (640;± 92 ms vs. 378;± 49 ms, p < 0.001 and 294;± 75 ms vs. 70;± 40 ms, p < 0.001 respectively). Receiver operator characteristics curve identified PPI-TCL >160 ms as 100% sensitive and specific for diagnosing VT (p < 0.001). Response to atrial entrainment can be helpful in the majority of WCT patients, particularly those with 1:1 AV relationship to diagnose or rule out VT as a mechanism of tachycardia with high accuracy.

Taquicardia de QRS largos – importância eletrocardiográfica no diagnóstico diferencial

Correct diagnosis in wide QRS complex tachycardia remains a challenge. Differential diagnosis between ventricular and supraventricular tachycardia has important therapeutic and prognostic implications, and although data from clinical history and physical examination may suggest a particular origin, it is the 12‐lead surface electrocardiogram that usually enables this differentiation.Since 1978, various electrocardiographic criteria have been proposed for the differential diagnosis of wide complex tachycardias, particularly the presence of atrioventricular dissociation, and the axis, duration and morphology of QRS complexes. Despite the wide variety of criteria, diagnosis is still often difficult, and errors can have serious consequences. To reduce such errors, several differential diagnosis algorithms have been proposed since 1991. However, in a small percentage of wide QRS tachycardias the diagnosis remains uncertain and in these the wisest decision is to treat them as ventricular tachycardias.The authors’ objective was to review the main electrocardiographic criteria and differential diagnosis algorithms of wide QRS tachycardia.

The value of electrocardiography for differential diagnosis in wide QRS complex tachycardia

Correct diagnosis in wide QRS complex tachycardia remains a challenge. Differential diagnosis between ventricular and supraventricular tachycardia has important therapeutic and prognostic implications, and although data from clinical history and physical examination may suggest a particular origin, it is the 12-lead surface electrocardiogram that usually enables this differentiation.Since 1978, various electrocardiographic criteria have been proposed for the differential diagnosis of wide complex tachycardias, particularly the presence of atrioventricular dissociation, and the axis, duration and morphology of QRS complexes. Despite the wide variety of criteria, diagnosis is still often difficult, and errors can have serious consequences. To reduce such errors, several differential diagnosis algorithms have been proposed since 1991. However, in a small percentage of wide QRS tachycardias the diagnosis remains uncertain and in these the wisest decision is to treat them as ventricular tachycardias.The authors’ objective was to review the main electrocardiographic criteria and differential diagnosis algorithms of wide QRS tachycardia.

Wide Complex Tachycardia in the Presence of Class I Antiarrhythmic Agents: A Diagnostic Challenge

We present two patients with paroxysmal atrial fibrillation on class 1C antiarrhythmic drugs without concomitant atrioventricular (AV) nodal blocking agents who developed atrial flutter with 1:1 AV conduction. Their electrocardiogram revealed wide complex tachycardia with rates >200/minute. Atrial flutter with 1:1 conduction in the presence of class IC antiarrhythmic drugs may present a diagnostic challenge. These cases illustrate the importance of coadministering an AV nodal blocking agent with class IC antiarrhythmic agents in patients with atrial fibrillation. The differential diagnosis of wide complex tachycardia in patients taking class IC agents should include atrial flutter with 1:1 AV conduction.

Arrhythmias in the Coronary Care Unit

Symptomatic sustained cardiac arrhythmias are frequently observed in in the coronary care unit and often lead to hemodynamic compromise, especially in the presence of multisystem disease. The predominant arrhythmias noted in intensive care units are tachyarrhythmias, particularly atrial fibrillation and flutter, and ventricular tachycardia. Bradycardias, arguably less life-threatening than tachyarrhythmias, can arise from sinus node dysfunction or atrioventricular conduction block; transient vagally-mediated bradycardias are frequently encountered as well. Prompt diagnosis of the patient with tachycardia is critical as treatment depends on the accurate diagnosis of tachycardia mechanism. The electrocardiogram remains the most important diagnostic tool for the evaluation of both wide and narrow complex tachycardia. The electrocardiographic diagnosis of wide complex tachycardia is based on evaluation of atrioventricular relationship and QRS morphology while the diagnosis of narrow complex tachycardia is based on the location and morphology of P waves. It is important for critical care specialists to understand the principles of cardiac arrhythmia diagnosis and remain current with the recent advances in the pharmacologic and non-pharmacologic management of patients with arrhythmias.

Implications of Progressive Aberrancy Versus True Fusion for Diagnosis of Wide Complex Tachycardia

At the onset of wide complex tachycardia, beats with intermediate morphologies sometimes occur between the normally conducted beats and the wide complex tachycardia QRS. Intermediate beats could be true fusion; however, progressive aberrancy has been reported to mimic true fusion. To evaluate the incidence of progressive aberrancy, wide complex tachycardia tracings were collected in which an intermediate beat was noted at the onset. When the associated electrocardiographic findings were diagnosed as supraventricular tachycardia, the beat was identified as progressive aberrancy. When diagnosed as ventricular tachycardia, the intermediate beat was identified as true fusion. Electrocardiographic criteria were then identified from this cohort to identify the distinguishing features between progressive aberrancy and true fusion. Of 24 episodes of wide complex tachycardia, 17 (71%) were identified as true fusion and 7 (29%) as progressive aberrancy. The QRS duration of the intermediate and wide complex tachycardia beats were shorter with progressive aberrancy than with true fusion (109 ± 23 ms vs 131 ± 20 ms, p <0.023; and 139 ± 21 ms vs 177 ± 24 ms, p <0.001, respectively). In progressive aberrancy (n = 3), the PR interval of the intermediate beat was always greater than the PR interval of the normally conducted beat. In contrast, in true fusion (n = 11), the PR interval of the intermediate beat was always less than the PR interval of the normally conducted beat. Multiple intermediate beats were present in 4 of 7 cases of progressive aberrancy and in 0 of 17 cases of true fusion. In conclusion, true fusion is the most common explanation for intermediate beats, but progressive aberrancy occurs a significant proportion of the time (29%). The identified criteria will be helpful in differentiating ventricular tachycardia from supraventricular tachycardia with aberrancy as a cause of wide complex tachycardia.

A Technique for the Rapid Diagnosis of Wide Complex Tachycardia with 1:1 AV Relationship in the Electrophysiology Laboratory

The differential diagnosis of wide complex tachycardia (WCT) with 1:1 atrioventricular (AV) relationship is broad. Accurate identification of the tachycardia mechanism is essential for successful ablation. We suggest a simple pacing maneuver that can immediately clarify the tachycardia mechanism in the electrophysiology laboratory. Eight consecutive patients (four males, 32 +/- 14 years) demonstrating stable sustained WCT with persistent 1:1 AV relationship during electrophysiologic testing were included in this study. During the tachycardia, atrial overdrive pacing was performed. The following responses were observed: (1) a change of the QRS morphology during atrial pacing and (2) the first return electrogram of the tachycardia, whether occurring in the atrium (AVA response) or in the ventricle (AVVA response). Atrial overdrive pacing was successfully performed in all patients. It was associated with either a change or narrowing of the QRS in all ventricular tachycardia (VT) patients but not in supraventricular tachycardia (SVT) patients. All VT patients had an AVVA response upon cessation of atrial overdrive pacing as opposed to AVA response in SVT patients, P = 0.029. The response to atrial overdrive pacing during WCT with 1:1 AV relationship can rapidly diagnose or rule out VT as a mechanism of tachycardia.

A new algorithm in the differential diagnosis of wide complex tachycardia

A correct electrocardiographic diagnosis of the mechanism of a wide complex tachycardia (WCT) is important when instituting emergent therapy and for long-term prognostic and therapeutic considerations. While any algorithm has the risk of oversimplifying a complex problem, it is absolutely essential to have an initial strategy for the acute evaluation of an arrhythmia. Causes of wide QRS tachycardia include (1) supraventricular tachycardia (SVT) with pre-existing or functional bundle branch block, including sinus tachycardia, atrial tachycardia, atrial flutter, atrial fibrillation (AF) and AV nodal re-entry tachycardia, (2) orthodromic circus movement tachycardia with pre-existing or functional bundle branch block, (3) SVT with conduction over an accessory pathway, (4) Antidromic circus movement tachycardia using an accessory pathway in the anterograde direction and AV node in the retrograde direction, (5) ventricular tachycardia, and (6) ventricular paced rhythm. Ventricular tachycardia is by far the commonest underlying mechanism of WCT.1 The overall goal of any algorithm is to make things simpler yet effective. Most criteria are based on QRS complex duration, QRS axis, concordant pattern, presence of Q-waves, AV dissociation, fusion beats, absence of precordial RS complex, QRS alternans, and presence of multiple wide complex morphologies. Starting in 1978, several criteria have been developed to aid in the diagnosis of WCT. For evaluation of RBBB morphology tachycardias,Wellens et al .2 proposed (1) duration of QRS > 140 ms, (2) left-axis deviation, (3) certain configurational characteristics of QRS, and (4) atrioventricular (A-V) dissociation as the criteria for … *Corresponding author. Tel: +1 617 632 7393; fax: +1 617 632 7620. E-mail address : mjoseph2{at}caregroup.harvard.edu

Electrocardiographic manifestations: wide complex tachycardia due to accessory pathway

Tachycardia with a wide QRS complex is usually due to ventricular tachycardia (VT), supraventricular tachycardia (SVT) with aberrant intraventricular conduction, or an accessory pathway-mediated dysrhythmia. The most common type of accessory pathway causing a wide complex tachycardia is the atrioventricular bypass tract. Distinguishing the accessory pathway-mediated tachycardia from VT or SVT with aberrancy is often difficult, but has important clinical consequences. This article will review the diagnosis of wide complex tachycardia due to an accessory pathway and its related management in the emergent setting.

Physician interpretation of electrocardiographic artifact that mimics ventricular tachycardia

BACKGROUND: Patients who are misdiagnosed with ventricular tachycardia because of electrocardiographic artifact may be subjected to unnecessary procedures. The purpose of this study was to determine how often electrocardiographic artifact is misdiagnosed as ventricular tachycardia. METHODS: Physicians (n = 766) were surveyed with a case simulation that included a two-lead electrocardiographic monitor tracing of artifact simulating a wide-complex tachycardia. RESULTS: The rhythm strip was not recognized as artifact by 52 of the 55 internists (94%), 128 of the 221 cardiologists (58%), and 186 of the 490 electrophysiologists (38%). One hundred fifty-six of the 181 electrophysiologists (88%), 67 of the 126 cardiologists (53%), and 14 of the 15 internists (31%) who misdiagnosed the rhythm as ventricular tachycardia recommended an invasive procedure for further evaluation or therapy. CONCLUSIONS: This physician survey suggests that electrocardiographic artifact that mimics ventricular tachycardia may frequently result in patients being subjected to unnecessary invasive cardiac procedures. Physicians should include artifact in their differential diagnosis of wide complex tachycardias to minimize unneeded procedures.

Use of Telemetered Permanent Pacemaker Intracardiac Electrograms to Diagnose Ventricular Tachycardia

The proper diagnosis of wide complex tachycardia can be difficult. Atrioventricular (AV) dissociation is generally diagnostic of ventricular tachycardia, but can be difficult to discern on the surface electrocardiogram. Increasingly sophisticated pacemaker diagnostic functions have been designed to aid in the management of pacemaker patients with paroxysmal atrial tachyarrhythmias, chronotropic incompetence, and syncope. In addition, telemetered intracardiac electrograms have been available for clarification of pacemaker function as well as diagnosis of arrhythmias.[ 1 Kamalvand K Tan K Willems R Sulke N Use of pacemaker diagnostic functions for recognition and management of cardiac arrhythmias. PACE. 1996; 19: 514-515 Crossref Scopus (5) Google Scholar ] In this case report, we describe a patient in whom wide complex tachycardia was misdiagnosed as supraventricular tachycardia (SVT) with aberrancy until telemetered intracardiac electrograms confirmed atrioventricular dissociation diagnostic of ventricular tachycardia (VT).

Wide Complex Tachycardias: Differential Diagnosis and Management

The majority of wide complex tachycardias are secondary to VT. The differential diagnosis of wide complex tachycardia also includes SVT with aberrancy or underlying bundle branch block and antegrade SVT conduction over an accessory pathway (antidromic SVT). VT is usually the result of reentry and most commonly arises in an area of diseased myocardium in the setting of previous myocardial infarction or cardiomyopathy. VT, however, can also occur in patients with structurally normal hearts. Criteria useful in diagnosis of wide complex tachycardia include clinical criteria (presence of structural heart disease or a history of previous myocardial infarction) and electrocardiographic criteria (the presence of capture or fusion beats, relation of atrial or ventricular activity, QRS duration and axis, and morphology). The acute management of wide complex tachycardia includes cardioversion and intravenous pharmacologic therapy. Almost all patients with VT require chronic therapy, although in rare patients treatment of acute precipitating factors may be sufficient. While pharmacologic therapy has been the mainstay of treatment for these patients, there have been many exciting advances using surgical, device, and ablative therapies.