Antidromic Tachycardia Research Articles

Wolff Parkinson White Syndrome with Rheumatic Mitral Stenosis: Double Trouble – Single Solution

WPW syndrome with rheumatic mitral stenosis is a rare and deadly combination. We report a patient with the above combination, presenting with drug-refractory antidromic tachycardia due to left atrial flutter and marked dyspnea. She underwent successful radiofrequency ablation of left-sided accessory pathway, left atrial flutter, and percutaneous mitral commissurotomy in a single sitting.

Antidromic AVRT with changing His activation. What is the mechanism?

We present a case of antidromic AVRT involving an atriofascicular pathway in a patient with an atretic coronary sinus os. This patient had left ventricular dysfunction with rate-related left bundle branch block aberrancy in sinus rhythm. In the electrophysiology lab, there was VA dissociation for a few beats during antidromic tachycardia. The possible mechanisms that could explain this intracardiac finding are discussed.

A rapid wide complex tachycardia

A rapid wide complex tachycardia

Wolff-Parkinson-White syndrome and dilated cardiomyopathy: Not only an electrical issue?

The present case describes a dilated cardiomyopathy associated with both antidromic and orthodromic atrio-ventricular reentrant tachycardias supported by multiple right accessory pathways. Both right accessory pathways were successfully eliminated by catheter ablation and the patient progressively recovered during the follow up. The following etiologies might be involved: 1) primitive dilated cardiomyopathy (or post-inflammatory); 2) septal dyssinchrony due to ventricular pre-excitation; 3) tachycardiomyopathy.

Not Just a One-Way: Mahaim Accessory Pathway Concomitantly Supporting Orthodromic Atrioventricular Re-Entrant Tachycardia

We report the case of a 41-year-old female with documented narrow QRS tachycardia. During electrophysiological study, both orthodromic and antidromic atrioventricular reentry tachycardia (AVRT) were demonstrated as well as short episodes of pre-excited atrial fibrillation. Programmed atrial stimulation resulted in decremental anterograde conduction on the AP, thus confirming an unexpected Mahaim accessory pathway (AP) diagnosis. Limited 3D activation maps of the right atrium during orthoAVRT, respectively, and the right ventricle (RV) during antiAVRT were constructed and helped accurately describe the atrial and ventricular insertion points, which were superposed on the tricuspid ring, confirming the existence of a single short atrio-ventricular right free wall AP. Short atrioventricular APs with anterograde Mahaim-type conduction concomitantly sustaining orthodromic AVRT are extremely rare. Electroanatomical 3D mapping may help both to clarify the diagnosis and increase the success rate by accurately describing the insertion points of complex accessory pathways.

A wide QRS tachycardia with the short and long ventriculoatrial interval in the presence of an atriofascicular pathway: What is the mechanism?

Duality of conduction over atriofascicular (AF) fibers because of longitudinal dissociation reportedly explains cycle length alternans and/or VA changes during antidromic AF tachycardia. Spontaneous or ablation-heated AF automaticity is also kept in mind in the differential diagnosis of AF-related tachycardias. The change in the rate between the wide and the narrow QRS complex tachycardia, and the presence of fusion give us important clues in differential diagnosis for active or bystander participation of AF pathway or AF automaticity. This article is protected by copyright. All rights reserved.

The Risk of Sudden Death Associated with Symptomatic and Asymptomatic Ventricular Pre-excitation in Athletes

Abstract Sudden death (SD) in athletes is a potential avoidable dramatic scenario. When done regularly, cardiological evaluation increases the chances of diagnosing ventricular pre-excitation. Consequently, the following question arises: what is the real incidence of SD risk in athletes with Wolff-Parkinson-White (WPW) syndrome/pattern? This study included 84 consecutive patients diagnosed with WPW and was designed as a retrospective analysis of data acquired between 2011 and 2021 to answer this question. The patients were evaluated using a 12-lead electrocardiogram (ECG), echocardiography, stress test, and electrophysiological study (EPS). The SD risk linked to WPW was defined as ≥ 1 of the following: the anterograde effective refractory period (AERP) of the accessory pathway (AP) ≤ 250 ms, atrial fibrillation (AF) with the shortest RR pre-excited interval ≤ 250 ms, syncope during AF or atrioventricular reentry tachycardia. The athletes with WPW pattern (n=25) or syndrome (n=59) at risk of SD were identified and treated with radiofrequency ablation (RFA). The mean age was 19.83 (10–29) years; 66.6% were men. Seventeen athletes (n=17; 20.23%) were found with SD risk: 15 (n=15; 17.85%) in the WPW syndrome group and 2 (n=2; 2.38%) in the WPW pattern group. During the EPS, n=4 developed syncope: 1 during antidromic tachycardia and 3 during pre-excited AF. RFA was curative in 96.42% of cases. The EPS is mandatory to identify athletes with short AERP APs linked to an increased risk of SD. RFA is the intervention that settles the patients into a risk-free area, allowing resumption of sports shortly afterward.

547 Supernormal conduction of an accessory pathway: the case of a young sportsman

Abstract Aims Ventricular pre-excitation is defined by the presence of all of the following electrocardiographic criteria: PQ interval duration ≤120 ms, QRS duration ≥120 ms, and presence of δ wave (defined as initial ‘slurring’ of the QRS complex). Ventricular pre-excitation together with the presence of symptoms (orthodromic and/or antidromic atrioventricular reentry tachycardia, atrial fibrillation) defines Wolff–Parkinson–White (WPW) syndrome. The anatomical substrate of ventricular pre-excitation consists of an extranodal accessory atrio-ventricular connection: the so-called Kent bundle. Such pathways can have antegrade, retrograde, or mixed conductive properties. Accessory pathways endowed with anterograde conductive capability may be responsible for manifest, intermittent, or non-manifest ventricular pre-excitation depending on whether it is respectively always visible on the ECG, not always visible on the ECG and not visible on the ECG even though the pathway has the ability to antegrade conduction. The rare phenomenon of supernormal conduction of anomalous pathways is part of the manifest pre-excitation, which represents the topic of the case reported below. Methods and results We report the clinical case of a young not agonist sportsman undergoing an electrophysiological study (SEF) because of he is suffering from ventricular pre-excitation. The SEF did not showed the inducibility of arrhythmias and, at the same time, apparently it showed low risk characteristics of the pathway even during adrenergic stimulus. However, a careful study, performed with atrial stimulation with couplings up to refractoriness of the atrioventricular node revealed supernormal conduction properties of the Kent bundle which proved to have high risk characteristics according to current guidelines and, therefore, was effectively treated with catheter ablation. Conclusions This case invites us to careful studying of accessory pathways properties, especially since, although rare, they may possess supernormal conduction characteristics capable of determining high ventricular rates in the case of sustained atrial tachyarrhythmias, especially in conditions of adrenergic hyperactivity.

Antidromic atrioventricular reentrant tachycardia in a patient with Wolff-Parkinson-White syndrome and unapparent preexcitation: A case report.

This is a case of antidromic AVRT in a patient with unapparent preexcitation, and we could successfully diagnose and treat with the careful interpretation of wide QRS tachycardia. We should keep in mind that differentiation between intermittent and unapparent preexcitation is difficult, and some patients with unapparent preexcitation have short refractory periods of those accessory pathways, leading to sudden death.

Редкий случай развития инфаркта миокарда 2-го типа у пациента с синдромом Вольф-Паркинсон-Уайта

Currently, myocardial infarction diagnostics has no diffi culties. Type 2 myocardial infarction is an exception, as it occurs due to a mismatch with oxygen delivery along coronary arteries and myocardial demand for it. Th e disease is secondary and this is the main diffi culty for its diagnostics. The article described a case of a young man having Wolff -Parkinson-White syndrome with type 2 myocardial infarction development. The main cause of myocardial necrosis is a prolonged paroxysm of reciprocal atrioventricular antidromic tachycardia.

Catheter ablation of an antidromic atrioventricular reentrant tachycardia using a slow, decrementally conducting accessory pathway in the great cardiac vein

The inability to ablate left accessory pathways (APs) from endocardial approaches may suggest an epicardial location. We report on a 43-year-old woman presenting with a wide QRS tachycardia with Right Bundle Branch Block (RBBB) morphology, right inferior axis, and the "pattern break" appearance in V2 resembled the outflow tract ventricular tachycardia. An electrophysiology study confirmed an antidromic atrioventricular reentrant tachycardia using an antegrade slow, decrementally conducting AP that was successfully ablated in the great cardiac vein-anterior interventricular vein junction after failure of endocardial approach.

DISORDERS OF CARDIAC RHYTHM IN PATIENTS WITH PRE-EXCITATION SYNDROME OF VENTRICLES AND THEIR PHARMACOLOGICAL CORRECTION

The aim of the research was to analyze the possibility of using different antiarrhythmic agents in patients with pre-excitation syndrome and disorders of cardiac rhythm. Most typical disorders of cardiac rhythm in patients with pre-excitation syndrome are orthodromic reciprocating supraventricular tachycardia, antidromic supraventricular tachycardia, atrial fibrillation and atrial fibrillation. During attack of tachycardia in patients with syndrome of pre-excitation, different clinical symptoms can be observed. They can range from mild palpitation to syncope. This tachycardia can be even reason of sudden cardiac death. Main its mechanism is macroreentrant circuit involving the AV-node, the additional pathway, the atria, the ventricles. To arrest the attacks of atrioventricular reciprocating tachycardia in patients with WPW syndrome and with narrow complexes QRS, calcium channel blocker verapamil has efficacy in 95% of patients. However, for treatment this arrhythmia with wide complexes QRS verapamil is contraindicated. Besides, it should be taken in account that treatment with this type of cardiac arrhythmia cardiac glycosides is also forbidden. Verapamil and cardiac glycosides are contraindicated for termination of arrhythmia in patients with WPW syndrome and such disorders of cardiac rhythm as atrial fibrillation (flutter). For therapy of atrial fibrillation (flutter) in patients with WPW syndrome antiarrhythmic agents of agents of І A subclass (quinidine, procainamide, disopyramide, propafenone) and ІІІ class (amiodarone, sotalol) can be useful. For interruption of paroxysmal tachycardia in patients with pre-excitation syndrome antiarrhythmical preparations of plant origin (gilurytmal and allapinin) have high efficacy. Termination of paroxysmal tachycardia in patients with premature excitation of ventricles can be achieved after administration of antiarrhythmic agents of ІС subclass, in particular after using of propafenone and encainide. However, treatment with the help of these agents quite often leads to appearance of arrhythmogenic action. In pre-excitation syndrome and cardiac arrhythmias, it is impossible to use drugs, which cause the acceleration of conductivity of nerve impulses in additional pathways (cardiac glycosides, β-blocker agents, for example propranolol). In patients with paroxysmal atrioventricular reciprocating (circular) tachycardia digitalis and calcium channel blockers should be avoided. Such agents as digoxin and verapamil in this arrhythmia can turn out to be dangerous in WPW syndrome, since they raise the conductivity through additional conductive pathways.

NEW ELECTROCARDIOGRAPHIC CRITERIA FOR DIFFERENTIAL DIAGNOSIS OF TACHYCARDIAS WITH ADVANCED QRS COMPLEXES ACCORDING TO THE TYPE OF BLOCKADE OF LEFT BUNDLE OF HIS

Aim. To evaluate standard 12-lead electrocardiogram (ECG) indices for the differential diagnosis of left bundle branch block (LBBB) tachycardias.Material and Methods. The study analyses 244 ECG indices in 63 retrospective patients (85 males and 39 females aged 50±12 years) with LBBB type tachycardias. The electrophysiological study identified ventricular tachycardias (VT) (VT group, n=20), supraventricular tachycardias (SVT) with LBBB (SVT+LBBB group, n=23) or antidromic SVTs (WPW group, n=20). Unifactorial, multifactorial, and ROC analyses were performed to develop diagnostic ECG algorithms. The prognostic accuracy of the algorithms was subsequently evaluated in a prospective group of patients with LBBB tachycardias (n=57).Results. ECG signs of LBBB VTs were as follows: 1) the presence of the initial R wave in the lead aVL; 2) the absence of a split (M-shaped) R wave in the lead I; and 3) the S wave duration in the lead V1≤100 ms. For antidromic LBBB tachycardias, the ECG signs were as follows: 1) the duration of the R waves in the lead V2≥45 ms; 2) the absence of a split R waves (M-shaped) in the lead I; and 3) the duration of the R wave in the lead aVL>30 ms. The accuracy of the algorithm for diagnosis of VT with LBBB was 95% (sensitivity of 97%, specificity of 92%). The accuracy of the algorithm for diagnosis of antidromic tachycardias was 84% (sensitivity rate of 65%, specificity rate of 100%).Conclusion. Our data showed new very powerful criteria for differential diagnosis between various LBBB tachycardias even in comparison with well-known ECG algorithms of Wellens, Brugada, Griffith, Scheinman, Vereckei, Sasaki, et al.

NEW ELECTROCARDIOGRAPHIC CRITERIA FOR DIFFERENTIAL DIAGNOSIS OF TACHYCARDIAS WITH ADVANCED QRS COMPLEXES ACCORDING TO THE TYPE OF BLOCKADE OF LEFT BUNDLE OF HIS

Aim. To evaluate standard 12-lead electrocardiogram (ECG) indices for the differential diagnosis of left bundle branch block (LBBB) tachycardias.Material and Methods. The study analyses 244 ECG indices in 63 retrospective patients (85 males and 39 females aged 50±12 years) with LBBB type tachycardias. The electrophysiological study identified ventricular tachycardias (VT) (VT group, n=20), supraventricular tachycardias (SVT) with LBBB (SVT+LBBB group, n=23) or antidromic SVTs (WPW group, n=20). Unifactorial, multifactorial, and ROC analyses were performed to develop diagnostic ECG algorithms. The prognostic accuracy of the algorithms was subsequently evaluated in a prospective group of patients with LBBB tachycardias (n=57).Results. ECG signs of LBBB VTs were as follows: 1) the presence of the initial R wave in the lead aVL; 2) the absence of a split (M-shaped) R wave in the lead I; and 3) the S wave duration in the lead V1≤100 ms. For antidromic LBBB tachycardias, the ECG signs were as follows: 1) the duration of the R waves in the lead V2≥45 ms; 2) the absence of a split R waves (M-shaped) in the lead I; and 3) the duration of the R wave in the lead aVL>30 ms. The accuracy of the algorithm for diagnosis of VT with LBBB was 95% (sensitivity of 97%, specificity of 92%). The accuracy of the algorithm for diagnosis of antidromic tachycardias was 84% (sensitivity rate of 65%, specificity rate of 100%).Conclusion. Our data showed new very powerful criteria for differential diagnosis between various LBBB tachycardias even in comparison with well-known ECG algorithms of Wellens, Brugada, Griffith, Scheinman, Vereckei, Sasaki, et al.

Regular broad complex tachycardia in a patient with Ebstein's anomaly

Ebstein's anomaly (EA) is an uncommon congenital heart disease characterized by apical displacement of the tricuspid valve and atrialization of the right ventricle (RV). EA is associated with accessory pathways, especially right-sided, often multiple, providing a substrate for supraventricular tachycardia (SVT). Stretching and fibrosis of the right atrium and dysplastic RV provides additional substrates for other atrial and ventricular tachyarrhythmias. Differentiating preexcited antidromic tachycardia from ventricular tachycardia can be quite challenging, especially where there are no cardiac electrophysiology services. We present a case of regular broad complex tachycardia in a 1-year-old child admitted with heart failure.

Antidromic tachycardia with RR interval variability: Take a closer look at the VH intervals

Antidromic tachycardia with RR interval variability: Take a closer look at the VH intervals

An atriofascicular tract in a girl with Ebstein's anomaly and right bundle block

Described in this article is a clinical case of a 14-year girl with Ebstein's anomaly and a complex preexitation syndrome (two atrioventricular pathways and a true atriofascicular Mahaim's tract). The atriofascicular tract was involved in antidromic and orthodromic tachycardias. The Л-wave was absent initially, because the spontaneous right bundle block and the comparable AV conduction velocity imitated a normal sinus rhythm. All accessory pathways were eliminated successfully during catheter ablation.

Wide QRS complex supraventricular tachycardia with negative precordial concordance: Electrocardiographic clues for Mahaim pathway with Ebstein anomaly

Ebstein's anomaly is often accompanied by either Wolff-Parkinson-White syndrome or atriofascicular Mahaim. These bypass tracts give rise to antidromic atrioventricular (AV) re-entrant tachycardias, in which the bypass tract serves as the anterograde limb of the circuit and the AV node as the retrograde limb of the reentrant circuit. Since the antidromic AV reentrant tachycardia over a Mahaim fibre has a typically left bundle braunch block (LBBB) morphology, it is easy to make a misdiagnosis of supraventricular tachycardia with functional LBBB or even of ventricular tachycardia particularly in the presence of negative concordance. Some electrocardiographic clues might prevent misdiagnosis of ventricular tachycardia and inadvertent ICD implantation.

Mahaim fiber-mediated tachycardia

We present the case of a previously healthy 42-year-old man who attended the emergency department due to a sudden onset of rapid and regular palpitations. The ECG showed 190 bpm, wide QRS with left bundle branch block tachycardia. He was started on amiodarone with progression to 230 bpm, wide QRS tachycardia with multiple morphologies, followed by spontaneous conversion to sinus rhythm, normal PR interval and rS pattern in LIII. The echocardiogram was negative for structural heart disease. The electrophysiological study demonstrated the presence of an accessory pathway with anterograde decremental conduction and no retrograde conduction. Both episodes of clinical tachycardia were induced. A diagnosis of Mahaim fiber-mediated antidromic atrioventricular reentrant tachycardia and pre-excited atrial fibrillation was made. Mapping was performed with detection of an M potential (His-like) at the lateral region of the tricuspid ring followed by radiofrequency ablation with immediate success criteria. Post-ablation there was a change to a qR pattern in LIII. At 12-months follow-up there was no recurrence of the tachycardia.

The double adenosine test: A simple and non-invasive tip to unmask unapparent pre-excitations at the emergency department

We describe a simple method to unmask unapparent pre-excitations at the emergency room. This method allows a non-invasive and definite diagnosis of accessory pathways capable of anterograde conduction. In patients presenting with paroxysmal SVT, close inspection of the electrocardiogram during sinus rhythm should look for a pre-excitation. Unfortunately, a pre-excitation can be completely unapparent during sinus rhythm despite the presence of an antegradely conducting accessory pathway. This is typically the case in the so-called Mahaim fibers. These bypass tracts give rise to antidromic atrioventricular reentrant tachycardias, in which the bypass tract serves as the anterograde limb of the circuit and the atrioventricular node as the retrograde limb of the reentrant circuit. In these patients, it is easy to make a misdiagnosis of supraventricular tachycardia with functional left bundle branch block. Indeed, due to the slow and decremental conduction properties of these bypass tracts, the baseline ECG is either normal or shows only subtle pre-excitation. Herein, we describe a simple tip, consisting of two successive administrations of adenosine (during ongoing tachycardia [upper panel] and during sinus rhythm [lower panel]), to make a non-invasive and definite diagnosis of this condition at the emergency department. By blocking the anterograde conduction over the atrioventricular node, adenosine infusion during sinus rhythm will indeed result in ventricular activation occurring exclusively over the accessory pathway. Importantly, the use of this simple method to unmask accessory pathways capable of anterograde conduction is not limited to the diagnosis of Mahaim fibers. Indeed, it can be used more generally in patients presenting with paroxysmal SVT whenever the ECG following tachycardia termination does not definitely rule out the presence of an accessory pathway ( Fig. 1 ).