Fascicular Tachycardia Research Articles

Cardiac Memory T Waves After Termination of Fascicular Ventricular Tachycardia in the Emergency Room

Left posterior fascicular tachycardia (LPFVT) is a common type of idiopathic ventricular tachycardia that might be misdiagnosed as supraventricular tachycardia. Memory T wave is an inverted T wave that is seen after altered depolarization states such as pacemaker rhythm, ablated accessory pathways, ventricular tachycardia, or intermittent bundle branch blocks. Herein, we presented a young male patient who was admitted to the emergency room with FVT. After termination of tachycardia negative T waves (memory T wave) were seen. Memory T waves might be seen after the termination of FVT and must be differentiated from other causes of inverted T waves such as ischemia.

Mapping of Purkinje-related ventricular arrhythmias by a multispline catheter with small and close-paired electrodes: Comparison with conventional catheters.

Precise mapping of the Purkinje fiber network is essential in catheter ablation of Purkinje-related ventricular arrhythmias (PrVAs). We sought to evaluate the mapping ability of a multi-spline duodecapolar catheter (PentaRay) for PrVAs. Mappings of Purkinje fibers by PentaRay catheters were compared with those by conventional mapping catheters in consecutive patients undergoing catheter ablation of PrVAs from 2015 to 2022. Sixteen PrVAs (7 premature ventricular contractions or non-reentrant fascicular tachycardias [PVCs/NRFTs] and 9 fascicular ventricular tachycardias [FVTs]) were retrospectively studied. In PVCs/NRFTs, earliest preceding Purkinje potentials (PPs) could be recorded by the PentaRay catheters but not by the mapping and ablation catheters in 5 cases. At the earliest PP sites, the precedence from the QRS onset was greater, and the amplitude of the preceding potentials was higher in the PentaRay catheter compared with those in the mapping and ablation catheter (-62.0±42.8vs. -29.4±34.2ms, P=0.02; 0.45±0.43vs. 0.09±0.08mV, P=0.02). In FVTs, late diastolic potentials (P1) were recorded by the PentaRay catheters but not by the mapping and ablation catheters or the linear duodecapolar catheter in 2 cases. The amplitude of P1 was higher in the PentaRay catheter compared with that in the linear duodecapolar catheter and the mapping and ablation catheters (0.72±0.49vs. 0.17±0.18vs. 0.27±0.21mV, P=0.0006, P=0.002). The localized critical PPs, defined as the earliest preceding potentials in PVCs/NRFTs and P1 in FVTs, could be recorded in all the patients by the PentaRay catheter. The mapping ability of critical PPs of PrVAs was better with the PentaRay catheter than with the conventional mapping catheters (16/16vs. 9/16, P=0.004 by McNemar exact test). The PentaRay catheter has clinical advantages in mapping of the Purkinje fiber network to reveal critical PPs as ablation targets of PrVAs.

False Tendons in the Left Ventricle: Implications for Successful Ablation of Left Posterior Fascicular Tachycardias

BackgroundThe anatomical substrate for left posterior fascicular ventricular tachycardia (LPF-VT) is still unclear. ObjectivesThe purpose of this study is to describe the endocavitary substrate of the re-entrant loop of LPF-VT. MethodsA total of 26 consecutive patients with LPF-VT underwent an electrophysiology study and radiofrequency ablation. ResultsIntracardiac echocardiography imaging observed a 100% prevalence of false tendons (FTs) at the left posterior septal region in all patients, and 3 different types of FTs could be classified according to their location. In 22 patients, a P1 potential could be recorded via the multielectrode catheter from a FT. In 4 patients without a recorded P1 during LPF-VT, the earliest P2 potentials were recorded from a FT in 3 patients, and from a muscular connection between 2 posteromedial papillary muscles in 1 patient. Catheter ablation focused on the FTs with P1 or earliest P2 (in patients without P1) was successful in all 26 patients. After 19 ± 8.5 months of follow-up, no patients had recurrence of LPF-VT. ConclusionsFTs provide an electroanatomical substrate for LPF-VT and a “culprit FT” may be identified as the critical structure bridging the macro–re-entrant loop. Targeting the “culprit FT” is a novel anatomical ablation strategy that results in long-term arrhythmia-free survival.

Cardiac Arrhythmias in Pediatric Age: Are They Triggered by SARS-CoV-2 Infection?

Coronavirus disease 2019 is a highly contagious infectious disease. Research on heart rhythm disorders in children affected by COVID-19 infection is quite lacking. An infant and a congenital heart disease (CHD) teenager with a pacemaker presented fascicular tachycardia and atrial flutter, respectively, during COVID-19 pauci-symptomatic infection. The hemodynamic condition was always stable. The self-resolving trend of the atrial flutter and progressive resolution of the ventricular tachycardia occurred in conjunction with the negativization of the swab. These particular tachyarrhythmias have been reported as a form of potential arrhythmic complication during active pauci-symptomatic COVID-19 infection for the first time ever.

Recurrent course of post-inflammatory cardiopathy: lessons from past epidemics

Viruses are the most common etiological agents of myocardium inflammation. Today the Severe Acute Respiratory Syndrome coronavirus (SARS-CoV-2) causes a high incidence of myocarditis and pericarditis. As a hypothetical scenario, we present a clinical case of a patient who underwent viral myocarditis on the background of SARS in 2004, with recurrent myocarditis in ARVI, the last of which was initiated by SARS-CoV-2. A 61-year-old male patient, in 2004 contacted a representative of the People's Republic of China and after 4 days felt the symptoms of ARVI. Before the viral disease, he had excellent health, the absence of cardiovascular diseases and pathological heredity. Fever 38–39 °C, myalgia, headache, general malaise, dry obsessive cough persisted for a week. After the addition of shortness of breath, he was hospitalized. According to the data of X-ray and computed tomography, infiltrates of the lungs of both of the "frosted glass" type were revealed. According to the clinic and laboratory data, a diagnosis of severe “atypical viral pneumonia” was made, and a diagnosis of viral myocarditis was suggested. Echocardiography showed a decrease in the left ventricular ejection fraction up to 50% for the first time, without signs of coronary heart disease based on the results of further examination. Dry cough disturbed in the next 4 months, LVEF 48–50% and 1 functional class of heart failure persisted for 10 years. The patient had a flu with mild respiratory symptoms in 2015, but it triggered a recurrence of myocarditis. The examination revealed a decrease in LVEF up to 35%, the progression of dilatation of the heart cavities also without signs of coronary heart disease according to the results of the treadmill test and coronary angiography. Post-inflammatory cardiopathy progressed relatively quickly during the year. The minimum LVEF was 23%; a cardioverter-defibrillator was implanted for secondary indications; radiofrequency ablation of fascicular tachycardia was performed. It was followed by another period of stabilization: 2 functional class of heart failure, ICD shocks did not occur. The patient underwent COVID-19 with minimal respiratory symptoms in March 2021. It provoked another recurrence of myocarditis, diagnosed with an increase in troponin, cerebral natriuretic peptide, CRP, ESR and increasing heart failure during 3 months. Persistent paroxysms of atrial fibrillation with a decrease of LVEF 15% and anasarсa. A successful radiofrequency isolation of the pulmonary vein was performed in 2021. By November 2021, in the absence of paroxysms, it was possible to achieve compensation for heart failure up to class 1 according to Vasilenko–Strazhesko and NYHA, LVEF 28%.In order to understand the recurrent nature of myocarditis against the background of various respiratory viral infections, an analysis of the literature was carried out, including the described cases of myocardial inflammation against the background of the predecessors of the SARS-CoV-2 strain: SARS-CoV-1 and MERS. We also reviewed the data on the diagnosis of viral myocarditis in the realities of this pandemic. It reveals a large heterogeneity of signs of inflammation of the heart muscle according to different diagnostic methods and large interobserver variability, and challenges us about the need to revise the criteria for myocarditis in the case of COVID-19.

Tachycardia and Anxiety in a 14-year-old Boy

Tachycardia and Anxiety in a 14-year-old Boy

Importance of the Activation Sequence of the His or Right Bundle for Diagnosis of Complex Tachycardia Circuits.

In this review, we emphasize the unique value of recording the activation sequence of the His bundle or right bundle branch (RB) for diagnoses of various supraventricular and fascicular tachycardias. A close analysis of the His to RB (H-RB) activation sequence can help differentiate various forms of supraventricular tachycardias, namely atrioventricular nodal reentry tachycardia from concealed nodofascicular tachycardia, a common clinical dilemma. Furthermore, bundle branch reentry tachycardia and fascicular tachycardias often are included in the differential diagnosis of supraventricular tachycardia with aberrancy, and the use of this technique can help the operator make the distinction between supraventricular tachycardias and these other forms of ventricular tachycardias using the His-Purkinje system. We show that this technique is enhanced by the use of multipolar catheters placed to span the proximal His to RB position to record the activation sequence between proximal His potential to the distal RB potential. This allows the operator to fully analyze the activation sequence in sinus rhythm as compared to that during tachycardia and may help target ablation of these arrhythmias. We argue that 3 patterns of H-RB activation are commonly identified-the anterograde H-RB pattern, the retrograde H-RB (right bundle to His bundle) pattern, and the chevron H-RB pattern (simultaneous proximal His and proximal RB activation)-and specific arrhythmias tend to be associated with specific H-RB activation sequences. We show that being able to record and categorize this H-RB relationship can be instrumental to the operator, along with standard pacing maneuvers, to make an arrhythmia diagnosis in complex tachycardia circuits. We highlight the importance of H-RB activation patterns in these complex tachycardias by means of case illustrations from our groups as well as from prior reports.

The Role of the Left Septal Fascicle in Fascicular Arrhythmias: Clinical Presentation and Laboratory Evaluation.

This study describes a series of cases best explained by invoking the left septal fascicle (LSF) as a critical component of the arrhythmia circuit. Numerous anatomic studies have shown evidence of the LSF, but its precise role in the onset of arrhythmia is unclear. This paper presents 5 cases that implicated the LSF as a critical component of arrhythmogenesis. The first case had ventricular fibrillation repeatedly documented after a single premature atrial complex, produced left-sided conduction delay and simultaneous earliest activation of the left anterior fascicle (LAF) and left posterior fascicle (LPF). The LSF was ablated, resulting in an arrhythmia cure. The second case showed narrow QRS morphology during fascicular re-entrant tachycardia. The earliest mid-septal diastolic potentials had distal-to-proximal activation suggesting an LSF as a retrograde common pathway. The third case, with multiple ectopic Purkinje-related premature complexes exhibited earliest Purkinje potentials in the mid-septum, with subsequent anterograde activation of the LAF and LPF. Ablation of the LSF eliminated the premature ventricular complexes (PVCs). The fourth case demonstrated LPF and LAF PVCs. The His-left bundle activation showed earliest potentials at the proximal insertion of the left bundle during LPF PVCs, as well as a distal-to-proximal activation pattern duringLAF PVC, suggestive of LSF involvement. The fifth case had focal non-re-entrant fascicular beats successfully ablated over the LSF. Involvement of the LSF is suspected with presentation of multiform fascicular and narrow QRScomplex ventricular episodes of arrhythmia. Diagnoses and ablation require detailed mapping of the entire leftsided conduction system.

Transcatheter radiofrequency ablation using near-zero fluoroscopy in children with fascicular ventricular tachycardia: a single-centre experience

Fascicular tachycardia is a common form of sustained idiopathic left ventricular tachycardia. This study aimed to achieve successful results with catheter ablation procedures performed through three-dimensional electroanatomic mapping using near-zero fluoroscopy in fascicular tachycardia patients. In this study, we included 33 consecutive children with fascicular tachycardia, for whom we performed a transcatheter radiofrequency ablation procedure using the EnSite® system. Activation mapping was performed in all patients during tachycardia, and the earliest presystolic purkinje potentials were the target site for radiofrequency lesions. Twenty-five patients were male, and eight were female. The mean weight of the patients was 39.6±10.4kg, and the mean age was 13.6±2.5 years. The mean procedure time was 121.3±44.3minutes. The mean follow-up period was 18.4±6.5 months. No fluoroscopy was needed in 30 patients. The mean fluoroscopy time in the remaining patients was 166.6±80 seconds. All of the patients had left posterior fascicular tachycardia except for one who had left anterior fascicular tachycardia. The acute success rate was perfect (100%). No patients developed left bundle branch block or complete atrioventricular block. Recurrence developed in one patient. We suggest that radiofrequency ablations via an electroanatomic mapping system are quite safe and effective, with high success rates in paediatric patients with fascicular tachycardia. This method has the advantage of avoiding ionising radiation exposure for both the patient and operator, thus reducing the lifetime risk of malignancy in the paediatric population.

Mapping and Ablation of Fascicular Tachycardias (Reentrant and Nonreentrant).

Fascicular ventricular tachycardia (FVT) usually involves the left fascicular system; namely the left posterior fascicle, anterior fascicle, and rarely the upper septal fascicle. It may also involve the right Purkinje arborization. This tachycardia can be seen in normal heart or in the setting of structural heart diseases. Monomorphic FVT can be reentrant or nonreentrant and verapamil-sensitive left FVT is the second most common type of idiopathic ventricular tachycardia (VT) after right ventricular outflow tract VT. This article focuses on the practical approach for both reentrant and nonreentrant FVT, explaining the mechanism, electrocardiographic features, and electrophysiologic features of FVT.

Fascicular tachycardia in infancy and the use of verapamil: a case series and literature review

ObjectiveGuidelines state that verapamil is contraindicated in infants. This is based on reports of cardiovascular collapse and even death after rapid intravenous administration of verapamil in infants with supraventricular tachycardia...

Hemiblocks and the fascicular system: myths and implications.

The His bundle divides into the right bundle branch (RBB) and the more complex left bundle branch (LBB). The latter is typically represented as further dividing into anterior and posterior fascicles, and possibly an additional septal fascicle. This construct raises questions as to why conduction can be preserved in patients with "trifascicular block" and why it sometimes very difficult to ablate fascicular or papillary muscle tachycardias. The answer may be that the LBB is much more complex, variable, and interconnected and that the simple familiar constructs may have obstructed our understanding of conduction and tachycardias. Remarkably, the actual explanatory histopathology has been known for nearly half a century, spearheaded by the work of Demoulin and Kulbertus. One picture is worth a thousand words.

Fascicular Tachycardia: The Great Masquerader

SESSION TITLE: Cardiovascular Disease SESSION TYPE: Affiliate Case Report Poster PRESENTED ON: Tuesday, October 31, 2017 at 01:30 PM - 02:30 PM INTRODUCTION: Hemodynamically stable tachycardia in a young seemingly healthy individual is generally assumed to be supraventricular in origin. However there is a type of ventricular tachycardia (VT) that has a relatively narrow complex that presents in young healthy individuals and is frequently misdiagnosed as supraventricular ventricular tachycardia (SVT). We present such a case and demonstrate the consequence of delayed diagnosis. CASE PRESENTATION: Our case is a 39 year old male with no past medical history who presented to our emergency department with one day of palpitations and diaphoresis. He first noted these symptoms in adolescence, which were of shorter duration and therefore medical attention was never sought. On arrival to our institution the patient was hemodynamically stable on presentation with an unremarkable physical exam other than a pulse rate of 200 bpm with an EKG showing wide complex tachycardia (figure 1). In addition his blood chemistries were all within normal limits. Despite receiving multiple rounds of adenosine (6mg, 12mg, 12mg) followed by electrical cardioversion, patient remained in wide complex tachycardia. Patient was then given Diltiazem 20mg IVP, which resulted in conversion to normal sinus rhythm (figure 2). Closer investigation of the presenting ECG revealed a leftward (northwest) axis and an incomplete RBBB pattern with RSR’ complexes, a finding highly specific for ventricular tachycardia (VT). An Echocardiogram at our institution revealed no structural heart disease with normal ventricular systolic function. Patient was taken for further electrophysiological testing which confirmed Left Fascicular VT. Patient underwent radiofrequency catheter ablation without any complications. DISCUSSION: Fascicular tachycardia typically originates in the region of the left posterior fascicle and has a RBBB, left superior axis morphology and AV disassociation. In most, a resting EKG is normal and there is no evidence of structural heart disease evidenced by echocardiography and coronary angiography. The narrow QRS complex (typically 0.12 to 0.14 sec) morphology distinguishes fascicular VT from most VTs, but it also resembles SVT frequently leading to misdiagnosis. CONCLUSIONS: Our goal is to help clinicians, especially those who first encounter patients’ with this presentation, be cognizant about the subtle important features of fascicular tachycardia. When it comes to wide complex tachyarrhythmias’ clinicians often have a sense of uneasiness, further clouding their clinical judgment. It is therefore imperative to recognize cases of Idiopathic VT, precisely fascicular tachycardia so they can be differentiated from svt and treated appropriately. Reference #1: Brooks R, Burgess JH. Idiopathic ventricular tachycardia. A review. Medicine (Baltimore) 1988; 67:271. Reference #2: Belhassen B, Viskin S. Idiopathic ventricular tachycardia and fibrillation. J Cardiovasc Electrophysiol 1993; 4:356. DISCLOSURE: The following authors have nothing to disclose: Shahab Khan, Ravi Mann, Fawzi Ameer, David Slotwiner No Product/Research Disclosure Information

Human His-Purkinje System: Abnormalities of Conduction, Rhythm Disorders and Case Studies.

This review covers many of the arrhythmias and conduction abnormalities related to His-Purkinje System. These include junctional premature complexes, junctional and fascicular tachycardias, bundle branch reentry (BBR), and the role of apparent conduction in various forms of supraventricular tachycardias (SVT) with or without involvement of accessory pathways (AP).

Non-Reentrant Fascicular Tachycardia: Clinical and Electrophysiological Characteristics of a Distinct Type of Idiopathic Ventricular Tachycardia.

The most common form of idiopathic Purkinje-related ventricular tachycardia (VT) is the reentrant type. We describe the clinical and electrophysiological characteristics of focal non-reentrant fascicular tachycardia. Among 530 idiopathic VT patients who were referred for ablation, we identified 15 (2.8%) with non-reentrant fascicular tachycardia (11 men, 45±21 years). Sinus rhythm ECG showed normal conduction intervals with a His-ventricular interval of 41±4 ms. All patients had monomorphic VT (cycle length: 337±88 ms) with a relatively narrow QRS (123±12 ms), and they did not respond to verapamil during the initial presentation. VT exhibited right bundle-branch block/superior axis configuration in 11 patients (73%) and inferior axis in 3 (20%). In 1 patient (7%), VT exhibited left bundle-branch block/superior axis configuration. During ablation, spontaneous VT occurred in 3 patients (20%) and nonentraintable VT or identical premature ventricular complex was induced in 9 (60%). A high-frequency presystolic Purkinje potential was recorded during VT/premature ventricular complex, preceding the QRS by 25±16 ms. VT recurrence was observed in 4 patients (27%), and among them, 3 underwent pacemap-guided ablation during the first session. A second ablation with activation mapping guidance eliminated the VT during the 88±8-month follow-up. Among idiopathic VT cases referred for ablation, 2.8% were focal non-reentrant fascicular tachycardia, which had distinct clinical characteristics and usually originated from the left posterior fascicle, and less commonly from the left anterior fascicle and right ventricular Purkinje network. Catheter ablation is effective, whereas pacemap-guided approach is less efficacious.

The Fast Zone for Reentry.

Reentry is the most common mechanism for arrhythmia in patients treated in the electrophysiology laboratory. Mapping and defining the exact circuit to then allow targeting an ideal site for ablation is challenging.1 However, as reentry usually involves a relatively large circuit often coupled with a discrete slow zone of conduction, we are able to use the classical techniques of entrainment mapping to find and ablate the circuit isthmus containing the slow zone ablation for permanent elimination.2,3 See Article by Liu et al Typically, slow zones for conduction occur as a result of diseased myocardium in the vicinity of scars in patients with structural heart disease. Reentry seen in normal hearts often has the atrioventricular node serving as the primary slow zone of the tachycardia circuit, for example, in atrioventricular node reentrant tachycardia and accessory pathway-related tachycardia. Indeed, nodoventricular tachycardia, although a rare tachycardia, exists because of atrioventricular nodal participation unlike patients with a fasciculoventricular tract where no tachycardia has been described likely because of the absence of a slow zone. Reentry that involves the conduction system is in some ways paradoxical because the Purkinje system is specialized tissue with fast conduction velocity. Bundle branch reentrant tachycardia does occur but almost always in severely diseased hearts with both slowed conduction through the Purkinje tissue and diseased myocardium forming parts of the circuit.4 Left posterior fascicular tachycardia is an enigmatic arrhythmia that occurs in normal hearts. The involvement of the conduction system with no apparent slow zone and success with discrete ablation at apparently normal tissue yet with clear characteristics of reentry based on entrainment makes this arrhythmia unique and difficult to approach.5 Treating the arrhythmia as a small circuit reentry akin to a focal …

Novel Electrophysiology Signal Recording System Enables Specific Visualization ofthe Purkinje Network and OtherHigh-Frequency Signals.

High-frequency signals (e.g., Purkinje potentials) are of interest in arrhythmia syndromes such as fascicular tachycardia and ventricular fibrillation. However, restricted dynamic range and sampling rate in modern electrophysiology recording systems make it challenging to identify high-frequency,

Takotsubo syndrome/QTc interval prolongation/myocardial edema/cardiac sympathetic denervation/cardiac arrhythmias: A quintet needing exploration

Article history: Received 14 October 2015 Accepted 18 October 2015 Available online 19 October 2015 and favor “catecholaminergic, automatic, or fascicular tachycardias, with related cytosolic calcium overload” [2,8] inciting mechanisms. The opinion of the latter stems from the data about tissue level characterization deriving frommagnetic resonance imaging, showing absence of scar formation [7]. However this author has expressed the notion that myocardial edema (ME) developing in patients with TTS could have a “patchy” distribution, and thus engender the prerequisite substrate for

Catheter ablation of idiopathic ventricular tachycardia without the use of fluoroscopy

BackgroundCatheter ablation is the treatment of choice for many patients with idiopathic ventricular tachycardia (VT). Unfortunately, conventional catheter ablation is guided by fluoroscopy, which is associated with a small but definite radiation risk for patients and laboratory personnel. The aim of our study is to assess feasibility, success rate and safety of idiopathic VT ablation procedure performed without the use of fluoroscopy. MethodsNineteen consecutive patients undergoing idiopathic VT ablation at our institution have been included. The ablation procedures were performed under the guidance of electroanatomical mapping (EAM) system and intracardiac echocardiography (ICE). ResultsNineteen patients (mean age 38.7years) underwent ablation procedure for idiopathic VT. Twelve (63%) had outflow tract VT, 3 (18%) fascicular tachycardia, 2 (11%) peri-tricuspidal VT, 1 (5%) peri-mitral VT, and 1 (5%) lateral left free-wall VT. The mean procedural time was 170.2±45.7min. No fluoroscopy was used in any procedural phase. Acute success rate was 100%. No complication was documented in any patients. After a mean follow up of 18±4months, recurrences occurred in 2 patients. ConclusionsIn our preliminary experience idiopathic VT ablation without the use of fluoroscopy was feasible and safe, using a combination of EAM and ICE. Success rate was excellent with no complication.

Location.

Location.