Incessant Tachycardia Research Articles

Patients on the ledge; ablation of incessant tachycardia. A single centre registry

Abstract Background Incessant tachycardia was first described by Cassidy (1). in 1924, it is strongly associated with tachycardia induced cardiomyopathy. There is no data about its true incidence however, it seems to be more common during infancy and childhood. Objectives To present 5-year single centre experience in ablating incessant tachycardia in a cohort of pediatric and adult patients. Methods From 2018 to 2023, We reviewed patients presented to our centre with incessant tachycardia, their clinical data, ECGs, imaging modalities, procedures details & outcomes were examined thoroughly. Results Over 5 years, 900 patients were referred to our centre for ablation, among them 25 patients (2.7%) presented with incessant tachycardia. Of them: 10 patients were pediatrics (40%), the youngest was 40 days old, 3.4 Kg, 6 patients were haemdynamically unstable necessitating ventilation& IV supports, 14 patients had impaired EF, with the lowest EF of 20%.(A) Regarding the diagnosis, 14 patients had AT (4 CS ostium, 3 LAA, 2 parahisian, 2 Crista, 1 LSPV, 1 TA, 1RAA), 4 AVRT (2 concealed parahisian accessory pathways & 2 PJRT), 3 VT (2 scar related VT, 1 anterior papillary muscle), 4 AFL (3 CTI flutter & 1 mitral isthmus flutter). All patients were ablated using 3D mapping system except 4 pediatric patients (2 AT from CS, 2 concealed parahisian accessory pathways) due to accesses limitations or unavailability of 3D mapping, single catheter technique was used in one patient weighing 3.4kg with AT from CS (only one venous access accommodating 5F catheter could be obtained)(B), Rt & Lt jugular accesses were used for ablation of RAA AT in a pediatric patient with bilaterally occluded femoral veins.(C) NCC was used as a safe access for ablating parahsisan AT & accessory pathways in our cohort.(D) All patients had successful ablation with full recovery for those with impaired function except 2 patients of scar related VT as their EF was impaired previously. Regarding the complications, one patient had DVT and another patient had retroperitoneal hematoma, both were managed conservatively. Conclusion Incessant tachycardia ablation is quite challenging but carries good results. Careful planning, experienced team & selection of the appropriate approach are the keys for successful safe procedures.

Catheter ablation for focal atrial tachycardias during pregnancy: A systematic review

ObjectivePregnancy can trigger maternal tachycardias, and the onset of recurrent or incessant focal atrial tachycardia (AT) can lead to tachycardia-induced cardiomyopathy. Medical interventions are commonly employed, but they carry potential fetal and maternal risks. Catheter ablation (CA), particularly with non-fluoroscopic navigation systems, may be considered as an alternative. This systematic review aims to explore the feasibility and outcomes of CA for focal AT during pregnancy. MethodsA thorough literature search was conducted until September 30th, 2023, on PubMed, Embase, and Cochrane databases. Included articles described maternal focal ATs diagnosed through electrophysiological studies and treated with CA. Data derived from these studies were organized into tables and subsequently analyzed. ResultsOut of 278 papers reviewed, 15 articles involving 24 patients were retrieved. CA, utilizing radiofrequency energy achieved acute success in 95.8% of cases. Sixteen patients (66.7%) underwent complete fluoroless procedures, with two adverse events directly related to the procedure reported. Long-term follow-up revealed minimal AT recurrences, with a 0.06% arrhythmia burden in one case. ConclusionFocal ATs during pregnancy can be incessant and refractory to medical intervention, precipitating an acute decline in left ventricular ejection fraction. In this setting, CA emerges as an efficacious treatment modality, particularly in cases of tachycardia-induced cardiomyopathies. Whenever feasible, it is advisable to perform these procedures with minimal or no fluoroscopy guidance. Larger studies are needed to establish the safety and the efficacy of CA for focal ATs during pregnancy, as current research consists of case reports or small case series.

Double Ventricular Response with Aberrant Conduction Leading to Ventricular Dysfunction.

Double ventricular response (DVR), where a single P wave results in two QRS complexes, is a rare presentation of dual AV node physiology. It has been associated with ventricular dysfunction in the setting of incessant tachycardia. We present the case of an otherwise healthy adolescent who had frequent DVR without tachycardia leading to left ventricular dysfunction. Slow pathway modification led to a significant reduction in ectopy and normalization of ventricular function. This highlights that DVR without tachycardia might lead to ventricular dysfunction in pediatric patients. Slow pathway modification with reduction of ectopy may be sufficient to restore ventricular function.

Human Stem Cell-Derived Cardiomyocytes Integrate Into the Heart of Monkeys With Right Ventricular Pressure Overload.

Cardiac ventricular pressure overload affects patients with congenital heart defects and can cause cardiac insufficiency. Grafts of stem cell-derived cardiomyocytes are proposed as a complementary treatment to surgical repair of the cardiac defect, aiming to support ventricular function. Here, we report successful engraftment of human induced pluripotent stem cell-derived cardiac lineage cells into the heart of immunosuppressed rhesus macaques with a novel surgical model of right ventricular pressure overload. The human troponin+ grafts were detected in low-dose (2 × 106 cells/kg) and high-dose (10 × 106 cells/kg) treatment groups up to 12 weeks post-injection. Transplanted cells integrated and progressively matched the organization of the surrounding host myocardium. Ventricular tachycardia occurred in five out of 16 animals receiving cells, with episodes of incessant tachycardia observed in two animals; ventricular tachycardia events resolved within 19 days. Our results demonstrate that grafted cardiomyocytes mature and integrate into the myocardium of nonhuman primates modeling right ventricular pressure overload.

Case report: Para Hisian Atrial Tachycardia

Case report: Para Hisian Atrial Tachycardia

Incessant Ectopic Atrial Tachycardia Accompanied by Unusual Neurological Manifestations – Case Report and Literature Review

Incessant ectopic atrial tachycardia (EAT) is well-known in the electrophysiology world. However, once accompanied by neurological manifestations, hence is a dilemma. We are reporting a 26-year-old male presenting with incessant symptomatic EAT. Once cardioverted, he began to manifest cardiovascular stroke clinical symptoms. Further objective investigation revealed no evidence of cardioembolic stroke. Our aim of this case report is to explore if there is a true correlation between EAT and possible neurological association and open further guidelines related to research.

Congenital Junctional Ectopic Tachycardia in a 6-month-old boy treated with Ivabradine: A Case Report

Congenital junctional ectopic tachycardia (JET) is a rare tachyarrhythmia found in young infants and is often difficult to treat. JET is characterized by incessant tachycardia which causes ventricular dysfunction, heart failure and high mortality. Ivabradine is one of the newer antiarrhythmic drugs with special indications in decreasing heart rate in adults with chronic heart failure. It has shown promising role in congenital JET. However, there are no guidelines recommending ivabradine as a first-line agent for congenital JET. We report an infant with congenital JET who was successfully treated with ivabradine.

PO-04-060 FOUND WITH SOUND: INTRACARDIAC ECHOCARDIOGRAPHY CORRELATED WITH MEDIUM-OUTPUT PACING TO AVOID PHRENIC NERVE INJURY WITH RIGHT ATRIAL ABLATION

Catheter ablation within the right atrium can be limited by proximity to the phrenic nerve and potential for hemi diaphragmatic paralysis. High output pacing is frequently employed to map phrenic position relative to endocardium, particularly in relation to the superior vena cava and the right superior pulmonary vein. The use of intracardiac echocardiography (ICE) in correlation with lower output pacing to rigorously map the course of the right phrenic nerve along the right atrium has not been previously described. We describe a case of incessant right atrial tachycardia successfully mapped and ablated close to the phrenic nerve using a combination of ICE imaging and medium-output pacing to rigorously map the phrenic nerve. n/a An 18-year-old man with incessant atrial tachycardia was referred for repeat ablation following unsuccessful attempt at ablation at an outside institution. Prior ablation was limited by proximity to the phrenic nerve and transient phrenic nerve palsy with cryoablation at the mid crista terminalis. Epicardial access to deflect the phrenic nerve was anticipated. Atrial tachycardia was mapped endocardially prior to obtaining epicardial access. An ICE catheter was advanced to the SVC and used to identify the phrenic nerve. The course of the phrenic nerve was rigorously mapped with ICE and integrated into the CARTO navigational system (Biosense Webster). Pacing along the course of the phrenic nerve was performed at 10 mA to further refine the course of the phrenic nerve within the SVC and right atrium. Regions in close anatomic proximity to the phrenic nerve with loss of pace-capture correlated with sites of physiologic effusion, where pericardial fluid was concentrated and separation of the phrenic nerve from the visceral epicardium was noted. After mapping the phrenic nerve, endocardial ablation of atrial tachycardia was successfully performed in the absence of phrenic nerve injury without the need for epicardial access. Phrenic nerve injury may be prevented by rigorous mapping of the phrenic nerve within the right atrium using intracardiac ultrasound with medium-output pacing.

PO-03-171 MULTIFOCAL ECTOPIC PREMATURE PURKINJE-RELATED COMPLEXES SYNDROME IN CHILDREN

Multifocal ectopic premature Purkinje-related complexes syndrome is a rare form of arrhythmia involving the entire His-Purkinje system (HPS), characterized by frequent polymorphic premature ventricular contractions (PVCs) of relatively narrow QRS, which could be arising from the entire HPS and is associated with a high probability of dilated cardiomyopathy. We presented the clinical courses of 6 pediatric patients with multifocal ectopic premature Purkinje-related complexes syndrome. The charts of all pediatric patients with the diagnosis of multifocal ectopic premature Purkinje-related complexes syndrome in our institution were reviewed. Multifocal ectopic premature Purkinje-related complexes syndrome was diagnosed in 2 newborn infants and 4 adolescents in 4 unrelated families. Two 2 of them with medical refractory incessant tachycardia underwent multiple catheter ablations with complete resolution of arrhythmia in one. Both patients had pacemaker therapy for ablation induced complete heart block. Four patients were medically treated successfully: One with propranolol; one with ivabradine; and 2 with flecainide. Pathogenic SCN5A mutation was detected in 2 families. Multifocal ectopic premature Purkinje-related complexes syndrome should be considered in infants and children with frequent multifocal PVCs with relatively narrow QRS. Ivabradine or flecainide can reduce the arrhythmia burden. In severe cases, catheter ablation can provide cure albeit with high risk of ablation induced heart block.

Management of a recurrent pregnancy-related incessant adenosine-sensitive atrial tachycardia

Management of a recurrent pregnancy-related incessant adenosine-sensitive atrial tachycardia

Management of hemodynamically stable wide QRS complex tachycardia in patients with implantable cardioverter defibrillators.

The preparation phase includes reversal of potential arrhythmia "triggers", mild patient sedation, and patient monitoring for therapy delivery. Based on resource availability and competences, the most adequate therapeutic approach is chosen. This choice depends on whether a device specialist is readily available or not. In the case of ES in a "high-risk" patient an accelerated patient management protocol is advocated, which considers urgent ventricular tachycardia transcatheter ablation with or without mechanical cardiocirculatory support. Therapeutic phase is based on the use of intravenous anti-arrhythmic drugs mostly indicated in this clinical context are presented. Device interrogation is very important in this phase when sustained monomorphic VT diagnosis is confirmed, then ICD ATP algorithms, based on underlying VT cycle length, are proposed. In high-risk patients with intractable ES, intensive patient management considers MCS and transcatheter ablation. The patient is hospitalized for further diagnostics and management aimed at preventing arrhythmia recurrences.

112 A CASE OF INCESSANT SLOW-FAST AVNRT TREATED WITH HIS BUNDLE PACING

Abstract Introduction Slow-fast AVNRT can rarely present as incessant SVT, particularly in patients with increased HV interval. We describe a case of incessant typical AVNRT, treated without transcatheter ablation. Case Presentation An 83-year-old man, with history of PAF, was admitted to our ICU complaining of dyspnea, dizziness and amaurosis. His ECG at presentation depicted sinus bradycardia, first degree AVB (PQ=400 ms) and RBBB (Fig 1A). After betablocker wash-out period, we decided to perform CSP using HBP to ensure AV synchrony and restore physiological pacing. During wash-out period, an incessant regular wide complex tachycardia with RBBB morphology and ventricular rate of 110 bpm occurred: the tracing showed a P wave immediately after the QRS, with RP < PR (Fig 1B). The tachycardia was incessant also in the EP lab. By means of 2 pacing leads (RV lead in the apical septum and RA lead in right appendage) and one diagnostic decapolar catheter (Inquiry, 2-2-2 Abbott) in His region, all connected to the polygraph, we performed an EPS. HV interval in sinus rhythm was 60 ms, AH 340 ms. The electrograms during tachycardia showed HVA sequence and 1:1 VA association, VA< 70 ms, cycle length 520 ms. Pacing from RV lead, we performed the ventricular overdrive pacing maneuver obtaining a VAV response; PPI-TCL was 280 ms and SA-VA difference was 205 ms (Fig 2A). We also noted a VA linking response to atrial overdrive pacing, and AHA response at the end of maneuver excluding JT (Fig 2B). In addition, pacing by the His catheter during tachycardia, we interrupted the arrythmia: the V signal after the last paced beat was not followed by retro-conducted A signal (Fig 2C). Finally, by administrating adenosine 12 mg the tachycardia interrupted with A as last signal recorded (Fig 2D). All these findings were consistent with an incessant typical AVNRT. We chose to treat AVRNT with sequential atrial-His pacing, placing a third lead in His region and programming the device in DDD 70-120, with selective His bundle capture, not correcting the RBBB (Fig 1C, D). Discussion In patients with poor anterograde AV nodal conduction, also slow-fast AVNRT can present as incessant tachycardia. In fact, a shorter sinus cycle length or atrial extrasystole could initiate sufficient delay in anterograde conduction to allow for recovery in conduction in the retrograde direction led to a persistent tachycardia. This case highlights the value of performing EPS diagnostic maneuvers also during PM implantations in order to personalize therapy and programming.

Surgical treatment of a difficult case of atrial tachycardia requiring multiple electrophysiologic procedures

A 34-year-old male with incessant drug-refractory atrial tachycardia (AT) was referred to our clinic for catheter ablation. The procedure began with endocardial activation mapping. The earliest endocardial activation site was in the right atrial appendage (RAA). The procedure continued with mapping of the left atrium through a transseptal approach. The earliest local activation was recorded at the anterior site of the right pulmonary veins. Radiofrequency (RF) ablation of both localizations was performed synchronously but failed to terminate the arrhythmia. The procedure continued with isolation of the RAA using cryoballoon but failed again due to the anomalous structure of the RAA. Then, epicardial RF ablation was attempted but failed. Finally, AT could only be terminated by surgical excision of the RAA.

Question: Incessant wide QRS complex tachycardia refractory to amiodarone.

Question: Incessant wide QRS complex tachycardia refractory to amiodarone.

Recovery of cardiogenic shock with ablation of incessant tachycardia in a neonate

Supraventricular tachycardia (SVT) is one of the most common conditions in neonates that require emergency cardiac care. Its incidence in infancy is 0.06 and 0.25 per 1000 patients per year by the age of 1 month and one year respectively. The symptoms are usually nonspecific and include poor feeding, irritability, vomiting, cyanosis, and pallid spells. If the symptoms are unrecognized for hours to days, the infant can present with significant hemodynamic compromise or heart failure. Despite the success of conservative management in most cases, catheter ablation is required in cases of failure of medical treatment. We report a case of SVT ablation using a single catheter in a neonate who presented with tachycardia-inducedcardiomyopathy (TIC).

PO-672-02 TERROR FROM THE DEEP APPENDAGE: INCESSANT LEFT ATRIAL APPENDAGE ATRIAL TACHYCARDIA

Ablation in the left atrial appendage (LAA) is risky due to numerous ridges separated by thin tissue. There are few reported cases of successful ablation of incessant atrial tachycardia (AT) originating within the LAA.

An interesting sinus beat initiation of incessant permanent junctional reciprocating tachycardia (PJRT)

We describe a rare surface electrocardiogram (EKG) recorded sinus beat initiation of permanent junctional reciprocating tachycardia in a 40-year old female with structurally normal heart presenting with incessant tachycardia over last 48 hours refractory to intravenous amiodarone infusion. Our case is an interesting illustration of sinus beat initiation of PJRT which has been rarely reported.

An unusual incessant long RP tachycardia—What is the mechanism?

A 40-year-old man underwent a diagnostic electrophysiology study because of a slow incessant long RP supraventricular tachycardia (SVT). Echocardiography revealed an ejection fraction of 35%. Upon presentation to the electrophysiology laboratory, he was in SVT. His refractory ventricular premature depolarizations (VPDs) delivered from the right ventricular (RV) apex failed to affect the tachycardia; the responses to earlier VPDs and coronary sinus (CS) atrial premature depolarizations (APDs) are shown in Figure 1, top and bottom, respectively.

Abstract 11080: A Young Woman with Incessant Left Atrial Tachycardia

Introduction: Left atrial tachycardia (AT) is uncommon and usually does not occur in the absence of congenital heart disease, or prior catheter ablation (CA). Case: A 29-year-old woman with a 2-year history of SVT refractory to metoprolol and no prior CA presented to the emergency department with palpitations. Initial ECG showed a regular, narrow complex, short RP tachycardia, at 180 bpm, insensitive to adenosine and 2 electrical cardioversions. Echocardiogram showed LVEF of 40%. The patient underwent an entirely non-fluoroscopic electrophysiology study using intracardiac echocardiography and electroanatomic mapping (EAM). AT (cycle length 300 ms) was induced by programmed atrial stimulation with isoproterenol infusion. AT was confirmed with ventriculo-atrial dissociation after pacing maneuvers and adenosine administration. Right atrial (RA) activation map revealed early atrial activation in the mid coronary sinus (CS), raising suspicion of a left atrial (LA) origin. LA was accessed via transseptal puncture. The site of earliest atrial activation was in the LA wall inferior to the left inferior pulmonary vein (LIPV) ostium and was successfully terminated with radiofrequency ablation (40 W, 5 to 10 g) (Figure) with no further inducibility. The patient's symptoms resolved after the procedure. Discussion: Left AT usually originates from PVs or the atrial wall. The EAM in this patient showed centrifugal activation consistent with a focal mechanism. Adenosine is generally not helpful in terminating AT but is useful in diagnosis. Rapid conduction across the LA to CS may have given rise to early activation in the mid CS on RA mapping. However, LA mapping revealed that atrial activation was earliest in the LA wall inferior to the LIPV. Conclusion: AT is unusual in young, healthy women. A high index of suspicion to perform transseptal puncture can lead to successful ablation of AT with LA origin. We surmise that the patient’s EF may improve with termination of the tachycardia.

Reversible severe cardiomyopathy caused by aslow permanent tachycardia

Incessant narrow QRS complex tachycardias may result in severe tachycardia-induced cardiomyopathy even if the heart rate during tachycardia is only moderatelyelevated. The risk of ventricular deterioration is particularly increased in patients with underlying congenital heart disease. In these patients, drug treatment is often insufficient. Thus, catheter ablation of the arrhythmogenic substrate is required in the majority of patients. After successful ablation, ventricular function may recover completely.