Wide QRS Tachycardia Research Articles

An extremely wide QRS complex tachycardia induced by anamorelin.

Anamorelin, a ghrelin receptor agonist, is used for cancer-related cachexia but can induce life-threatening arrhythmias. A case study illustrates an extremely wide QRS tachycardia, posing diagnostic challenges. Anamorelin cessation led to normalization, highlighting the importance of ECG monitoring, particularly in liver-compromised patients, and hemodynamic support are crucial during suspected toxicity.

Bundle branch reentrant ventricular tachycardia in a patient with Fabry disease

BackgroundBundle branch reentrant ventricular tachycardia is a unique type of VT that employs both bundles and the ventricular septum as integral components of a re-entrant circuit. It is usually observed in dilated cardiomyopathy, and its circuit depends exclusively on the specialized conduction system.Case presentationA 67-year-old man with a history of Fabry disease, and atrial fibrillation ablation, was admitted for a wide QRS tachycardia at 150 bpm, with an LBBB. Pharmacological therapy failed to stop the arrhythmia. Intracardiac recordings confirm the diagnosis. His Bundle recordings are essential, and Atrioventricular (AV) dissociation is typically present. The method used to induce left BBRVT is right ventricle apex stimulation. An electrophysiological study showed an AV dissociation a long HV sequence and a similar QRS morphology between VT and sinus rhythm. An overdrive stopped it. The same arrhythmia reappears and is restored to sinus rhythm by electrical cardioversion. We decided to implant an Implantable Cardiac defibrillator (ICD) with a backup pacing for secondary prevention and to ablate the right bundle branch.ConclusionBBRVT is a rare entity that is underreported. Pharmacological therapy is usually inefficient. An ICD is recommended for secondary prevention and can provide backup pacing, frequently required after catheter ablation to prevent the development of AV block or an excessive prolonged HV interval. Catheter ablation of the bundle branch is the first-line therapy.

Narrow to wide QRS tachycardia: What is the mechanism?: To standby silently is to be an accomplice

Narrow to wide QRS tachycardia: What is the mechanism?: To standby silently is to be an accomplice

Discrimination between ventricular tachycardia and wide-QRS preexcited tachycardia.

To develop a new algorithm to differentiate ventricular tachycardia (VT) from preexcited tachycardia (pre-ET) according to left bundle branch block (LBBB) and right bundle branch block (RBBB) patterns. This study included 67 electrocardiograms (ECGs) with VT and 63 ECGs with pre-ET, collected from our hospital and through PubMed. Of those, 64 were allocated to the derivation cohort and the rest to the validation cohort. The diagnoses of the ECGs were confirmed using an electrophysiological study. Parameters and classifiers from prior algorithms along with the propagation speeds in the early portion of the QRS complex (initial deflection index) in leads V1, V6, aVR, II, and III were manually measured. The performance of the new algorithm was compared with that of prior algorithms. The initial deflection index in lead III was the strongest predictor of pre-ET in LBBB-pattern wide-QRS tachycardia (p = 0.003, AUC 0.805). The initial deflection index in lead V1 was the most powerful predictor of pre-ET in RBBB-pattern wide-QRS tachycardia (p = 0.001, AUC 0.848). Compared to earlier algorithms, those using the initial deflection indexes: lead III in LBBB patterns (cutoff value >0.3) and lead V1 in RBBB patterns (cutoff value ≤0.48), demonstrated superior performance in screening VT, with AUC values of 0.828. The initial deflection indexes proved effective as discriminators between VT and pre-ET in the validation cohort. In LBBB-pattern wide-QRS tachycardia, the early propagation speed of pre-ET was faster than that in VT. Conversely, in RBBB-pattern wide-QRS tachycardia, it was slower.

Wide QRS tachycardia: What is the mechanism?

Wide QRS tachycardia: What is the mechanism?

A machine learning approach to differentiate wide QRS tachycardia: distinguishing ventricular tachycardia from supraventricular tachycardia.

Differential diagnosis of wide QRS tachycardia (WQCT) has been a challenging issue. Published algorithms to distinguish ventricular tachycardia (VT) and supraventricular tachycardia (SVT) have limited diagnostic capabilities. A total of 278 patients with WQCT from January 2010 to March 2022 were enrolled. The electrophysiological study confirmed SVT in 154 patients and VT in 65 ones. Two hundred nineteen WQCT 12-lead ECGs were randomly divided into development cohort (n = 165) and testing cohort (n = 54) data sets. The development cohort was split into a training group (n = 115) and an internal validation group (n = 50). Forty ECG features extracted from the 219 WQCT ECGs are fed into 9 iteratively trained ML algorithms. This novel ML algorithm was also compared with four published algorithms. In the development cohort, the Gradient Boosting Machine (GBM) model displayed the maximum area under curve (AUC) (0.91, 95% confidence interval (CI) 0.81-1.00). In the testing cohort, the GBM model had a higher AUC of 0.97 compared to 4 validated ECG algorithms, namely, Brugada (0.68), avR (0.62), RWPTII (0.72), and LLA algorithms (0.70). Accuracy, sensitivity, specificity, negative predictive value, and positive predictive value of the GBM model were 0.94, 0.97, 0.90, 0.94, and 0.95, respectively. A GBM ML model contributes to distinguishing SVT from VT based on surface ECG features. In addition, we were able to identify important indicators for distinguishing WQCT.

Wide QRS Tachycardias Management in Emergency Departments: What Really Matters

Wide QRS Tachycardias Management in Emergency Departments: What Really Matters

The role of latrophilin-2 in maintaining cardiac cell-to-cell junctions and its implications for dilated cardiomyopathy and sudden death

Abstract Background Identifying genes that are important for maintaining heart function and characterizing their roles and pathways are essential for developing therapeutic approaches. Latrophilin-2 (LPHN2), a relatively unknown GPCR, critically contributes to differentiation from pluripotent stem cells (PSC) to the cardiac lineage, but it is not known whether LPHN2 is active in the adult heart. Purpose In this study, we explored the functions of LPHN2 in adult hearts. Methods and Results To determine whether there is an association between variation in LPHN2 and cardiac phenotypes in humans, we used gnomAD and UK Biobank data. The data suggested that LPHN2 variants could be fatal. Accordingly, we developed a mouse model for further analysis of Lphn2. Deletion of Lphn2 causes embryonic lethality, so we generated a cardiac-specific, tamoxifen-inducible Lphn2 conditional knockout mouse (Lphn2icKO mouse) by cross-breeding Lphn2flox/flox mice with the TMX-inducible Cre recombinase (MerCreMer) under control of the α-Myh6 (α-myosin heavy chain) promoter mice. After administering tamoxifen, we found that the left ventricle became dilated and the systolic function was decreased, and gaps were created between cardiomyocytes. We also observed ventricular tachycardia and atrioventricular block associated with the dilated cardiomyopathy and subsequent sudden cardiac death. Cell-to-cell junctions (adherence, gap, and desmosomes,) were found to be dysregulated in the Lphn2icKO adult mouse heart and the heart at embryonic day 13.5 of Lphn2−/− (homozygous Lphn2 deficiency). To investigate Lphn2 function in a disease model, we generated a myocardial infarction (MI) in Lphn2icKO mice. MI with tamoxifen group showed wide QRS tachycardia and various types of block, and a survival reduction of 40% compared with that of the MI group. Regarding underlying mechanisms, we found that PGC-1α, a factor downstream of p38-MAPK that contributes to arrhythmia and maturation of PSC-derived cardiomyocytes, was downregulated (Figure). Conclusions LPHN2 is a key molecule that maintain adult heart integrity via its effects on cell-to-cell junctions, and the deficiency of Lphn2 exacerbates heart failure. Our findings provide evidence in support of LPHN2 being a pivotal regulator of heart function through the p38-MAPK-PGC-1α pathway.Schematic illustration

A variability of the QRS morphology during wide QRS tachycardia.

A variability of the QRS morphology during wide QRS tachycardia.

Reversal of Supraventricular Tachycardia with Aberration afte Initiation of Pseudoanalgesia with Propofol: Case Report

Supraventricular tachycardia (SVT) is a heterogeneous group of arrhythmias used to describe tachycardias involving cardiac tissue at or above the level of the bundle of His. They usually appear in subjects without structural heart disease. However, they can sometimes cause palpitations, dyspnea, sweating, angina, or vague chest discomfort, particularly in patients with underlying heart disease. We present the case of a patient with SVT reverted during pseudonalgesia with propofol. This is a 48-year-old male patient who came for presenting a sensation of intense palpitations, an electrocardiogram was taken where the presence of wide QRS tachycardia was observed. It was decided to administer procedural sedation for synchronized electrical cardioversion, however, he presented cardioversion upon administration of propofol 50 mg (Fig 1B) after 5 minutes, improving the symptoms. Studies of propofol have described its influence on the cardiac conduction system and the ability to modify the phases of the action potential by acting on the ion channels of the myocyte membrane. Therefore, it would be interesting to see case series from large centers and electrophysiology studies that show the possible antiarrhythmic role of drugs such as propofol not described in the literature.

Arritmias cardíacas. Diagnóstico electrocardiográfico y manejo terapéutico en urgencias

Cardiac arrhythmias are a very common reason for consultation in emergency departments. The most common symptoms that occur are palpitations, chest pain, dyspnea, symptoms of low cardiac output, and syncope, although they can be diagnosed as an incidental asymptomatic finding. The detailed, systematic analysis of a 12-lead electrocardiogram is one of the fundamental tools for its diagnosis. They are classified as tachyarrhythmias and bradyarrhythmias, each of which has specific management according to the symptoms they produce and if they are accompanied by hemodynamic instability or not. Atrial fibrillation is the arrhythmia that causes the most consultations in the emergency department. When faced with wide QRS tachycardia, ventricular tachycardia should be suspected. Immediate care and treatment are needed to reverse it due to its potential mortality, even if it is associated with hemodynamic stability.

Comparison of the effectiveness of various valsalva maneuvers in the management of stable narrow and wide QRS complex tachycardia in the emergency department

Purpose: Narrow and wide QRS complex tachycardias are among the causes of arrhythmia in patients frequently admitted to the emergency department (ED). The first recommended step in the management of patients with a stable narrow and wide QRS tachycardia is a vagal maneuver. Althougah there are many maneuvers that can provide vagal stimulation, the most effective vagal maneuver is still unknown. This study aims at determining the most effective vagal maneuver by comparing the four most commonly used maneuvers.
 Materials and methods: One hundred and thirty-two patients were included in this study; they were randomly and equally distributed into four groups. Carotid sinus massage (CSM) was applied to the first group, the REVERT method was applied to the second group (a 10-cc injector was used), a modified REVERT method was applied to the third group (a 60-cc injector was used), and the abeslang (wooden tongue depressor) method was applied to the fourth group. During these four applications, the patients’ vital signs were monitored, and preparations were made for any emergency.
 Results: Of the 132 patients included in the study, 61 (46.2%) were males, and 71 (53.8%) were females. The average age of the patients was 56.3 years. One hundred and twenty-six had narrow QRS tachycardias, and 6 had stable wide QRS tachycardias. The patients were randomly distributed into 4 groups. In the 1st group, 1 patient (3%) returned to a normal rhythm with the CSM method. In the 2nd group, 3 patients (9.1%) returned to a normal rhythm with the REVERT method. Nine patients (27.3%) in the 3rd group returned to a normal rhythm with the modified REVERT method. 6 patients (18.2%) in the 4th group returned to normal rhythm with the abeslang method. None of the stable wide QRS tachycardias responded to vagal stimulation methods.
 Conclusion: The modified REVERT and abeslang methods are preferred primarily in patients entering the ED with the complaint of a stable narrow or wide QRS tachycardia in the case that a vagal maneuver is to be applied. On the other hand, a vagal maneuver is not effective in the management of a stable wide QRS tachycardia.

Lacosamide Intoxication-induced Wide QRS Tachycardia Successfully Treated with Veno-arterial Extracorporeal Membrane Oxygenation.

Lacosamide is an antiepileptic drug that acts on voltage-gated sodium channels and was approved as an antiepileptic by the Food and Drug Administration in 2008. Although the efficacy and safety of lacosamide have been established in many previous trials, some case reports have shown that it may lead to cardiovascular side effects, especially in patients with electrical conduction system disorders. We herein report a case of life-threatening cardiac arrhythmia caused by lacosamide intoxication that was successfully treated with veno-arterial extracorporeal membrane oxygenation.

The role of limb-leads criterion in diagnosing the mechanism of wide QRS tachycardias

Background: The limb-lead criterion is a simple new standard with high diagnostic value to distinguish the cause of wide QRS tachycardia, easy to apply in emergency conditions.
 Methods: A cross-sectional descriptive study of 61 patients with electrocardiogram of wide QRS tachycardia at Cardiovascular Center- Hospital E and Vietnam Heart Institute- Bach Mai Hospital from January 2017 to October -2022. Evaluating the value of limb – leads Criterionand comparing to several other criteria.
 Results: In 61 patients, 43 patients with VT, 18 patients with SVT, 54.1% male, history of ischemic heart disease (3.3%), heart failure (11.5%), no history structural cardiovascular disease (83.6%). Mean heart rate was 182, 80 ± 20.58 bpm, average QRS width was 137.89 ± 12.59mms. Sensitivity, specificity, positive predictive value, negative predictive value of Brugada criterionwere 97.7%, 88.9%, 95.5%, 94.1%, respectively; of Pava criterionwere 53.5%, 88.9%, 92%, 44.4%; of Vereckei criterionwere 60.5%, 100%, 100%, 51.4%; of limb-leads criterion is 86.1%, 83.3%, 92.5%, 71.4%; when combining Limb lead and Pava criteriawere 90.9%, 82.4%, 93%, 77.8%.
 Conclusion: The limb-lead criterion is an easy-to-usealgorithm, only using morphology to distinguish wide QRS tachycardias, has high diagnostic value, so it should widely applied in cardiovascular emergency.

Multiple wide QRS tachycardias in the same individual with ischemic cardiomyopathy.

The classic teaching over the years has been that all cases of WCT are to be treated as VT until proven otherwise, particularly in patients with structural heart disease. This case highlights an alternative diagnosis is possible This article is protected by copyright. All rights reserved.

Confounding factors leading to misdiagnosing ventricular tachycardia as supraventricular in the emergency room

Studies conducted during the last 50 years have proposed electrocardiographic criteria and algorithms to determine if a wide QRS tachycardia is ventricular or supraventricular in origin. Sustained ventricular tachycardia is an uncommon reason for consultation in the emergency room. The latter and the complexity of available electrocardiographic diagnostic criteria and algorithms result in frequent misdiagnoses. Good hemodynamic tolerance of tachycardia in the supine position does not exclude its ventricular origin. Although rare, ventricular tachycardia in patients with and without structural heart disease may show a QRS duration <120 ms. Interruption of tachycardia by coughing, carotid sinus massage, Valsalva maneuver, or following the infusion of adenosine or verapamil should not discard the ventricular origin of the arrhythmia. In patients with regular, uniform, sustained broad QRS tachycardia, the presence of structural heart disease or A-V dissociation strongly suggest its ventricular origin. Occasionally, ventricular tachycardia can present with AV dissociation without this being evident on the 12-lead ECG. Cardiac auscultation, examination of the jugular venous pulse, and arterial pulse palpation provide additional clues for identifying A-V dissociation during tachycardia. This paper does not review the electrocardiographic criteria for categorizing tachycardia as ventricular but rather why emergency physicians misdiagnose these patients.

Abstract 13915: Man vs. Machine: A Direct Comparison of the Diagnostic Efficacy of Novel Automated WCT Differentiation to Traditional Manual ECG Interpretation Approaches

BACKGROUND: Differentiation of wide QRS complex tachycardias (WCTs) into ventricular tachycardia (VT) and supraventricular wide QRS tachycardia (SWCT) through 12-lead electrocardiogram (ECG) interpretation is one of the most critical yet challenging tasks in clinical practice. Recent research highlights novel automated methods that successfully diagnose WCTs. We sought to directly compare the diagnostic efficacy of these novel automated WCT differentiation methods (i.e., WCT Formula, VT Prediction Model, and WCT Formula II) to traditional ECG interpretation approaches (i.e., Brugada and Vereckei aVR algorithms). METHODS: A collection of paired WCT and baselined ECGs were retrospectively analyzed. Next, an electrophysiologist blindly and prospectively applied the Brugada and Vereckei aVR algorithms. Separately, computerized measurements were used to apply the three automated WCT differentiation methods. The diagnostic performance of each method was then evaluated. RESULTS: 213 WCTs (111 VT and 102 SWCT) from 105 patients were analyzed. The WCT Formula demonstrated superior overall accuracy (84.7% vs. 64.8%), specificity (86.2% vs. 35.3%), positive predictive value (PPV) (85.7% vs. 60.7%), and positive (+) likelihood ratio (LR) (6.06 vs. 1.42) compared to Vereckei aVR algorithm. Similarly, the WCT Formula attained higher specificity (86.2% vs. 61.8%), PPV (85.7% vs. 71.9%), and (+) LR (6.06 vs. 2.36) than the Brugada algorithm. The WCT Formula II demonstrated superior overall accuracy (89.2% vs. 64.8%), specificity (84.3 % vs. 35.3%), PPV (86.7% vs. 60.7%), and positive (+) LR (5.97 vs.1.42) compared to Vereckei aVR algorithm as well as higher specificity (84.3 % vs. 61.8 %), PPV (86.7% vs. 71.9%), and (+) LR (5.97 vs. 2.36) than the Brugada algorithm. The VT prediction model yielded superior specificity (79.4% vs. 35.3%), PPV (79.8 vs. 60.7%) and (+) LR (3.63 vs.1.42) compared to the Vereckei aVR algorithm but did not demonstrate superior diagnostic performance to the Brugada algorithm. CONCLUSIONS: Novel automated WCT differentiation methods achieved similar or superior diagnostic performance metrics compared to traditional ECG interpretation approaches.

Transient baseline rhythm changes unmasking an uncommon arrhythmic substrate.

A 15-year-old female with recurrent episodes of wide-QRS tachycardia (Figure 1) responsive to intravenous adenosine was referred to our arrhythmia center to undergo an electrophysiological study (EPS) This article is protected by copyright. All rights reserved.

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.

Common Supraventricular and Ventricular Arrhythmias in Children.

The most common pediatric arrhythmias are tachycardias, and the most common type is supraventricular tachycardia, originating from or above the atrioventricular node and HIS bundle. Ventricular tachycardias are less common but more dangerous. Supraventricular tachycardias usually cause a narrow complex tachycardia unless there is a basal bundle branch block or rate-dependent aberration. A wide QRS tachycardia should be treated as ventricular tachycardias unless proven to be an supraventricular tachycardia with aberration. Diagnosis of both tachyarrhythmia types depends mainly on 12-lead electrocardiography. The most common supraventricular tachycardia type in newborns and infants is atrioventricular reentry tachycardia, related to manifest or concealed accessory pathways and in adolescent atrioventricular nodal reentry tachycardia, whereas focal atrial tachycardias consist of 10%-15% of supraventricular tachycardias during all ages. Supraventricular tachycardias have a low risk of morbidity, and ablation therapy is successful in most types with success rates over 90%. Ventricular tachycardias can be monomorphic or polymorphic, nonsustained or sustained, and can cause more hemodynamic instability than supraventricular tachycardias, requiring more close monitoring and urgent therapies. If hemodynamically unstable, synchronized cardioversion must be performed. Polymorphic ventricular tachycardias are very dangerous and often associated with primary ion channel defects (channelopathies), which can cause sudden cardiac death.