Ectopic Tachycardia Research Articles

Two decades of experience on ablation in children with Ebstein's anomaly.

Accessory pathways are commonly seen due to delamination of tricuspid valve leaflets. In addition to accessory pathways, an enlarged right atrium due to tricuspid regurgitation and incisional scars creates substrates for atrial re-entries and ectopic tachycardia. We sought to describe our experience with catheter ablation in children with Ebstein's anomaly. During the study period, of 89 patients diagnosed with Ebstein's anomaly, 26 (30.9%) of them who underwent 33 ablation procedures were included in the study. Accessory pathways were observed in the majority of procedures (n = 27), whereas atrial flutter was observed in five, atrioventricular nodal reentrant tachycardia in five, and atrial tachycardia in two procedures. Accessory pathways were commonly localised in the right posteroseptal (n = 10 patients), right posterolateral (n = 14 patients), septal (n=two patients), and left posteroseptal (n=one patient) areas. Multiple accessory pathways and coexistent arrhythmia were observed in six procedures. All ablation attempts related to the accessory pathways were successful, but recurrence was observed in five (19%) of the ablations. Ablation for atrial flutter was performed in five patients; two of them were ablated successfully. One of the atrial tachycardia cases was ablated successfully. Ablation in patients with Ebstein's anomaly is challenging, and due to nature of the disease, it is not a rare occasion in this group of patients. Ablation of accessory pathways has high success, but also relatively high recurrence rates, whereas ablation of atrial arrhythmias has lower success rates, especially in operated patients.

Quality of life assessment in children before and after a successful ablation for supraventricular tachycardia

Young patients suffering from rhythm disorders have a negative impact in their quality of life. In recent years, ablation has become the first-line therapy for supraventricular arrhythmias in children. In the light of the current expertise and advancement in the field, we decided to evaluate the quality of life in young patients with supraventricular arrhythmias before and after a percutaneous ablation procedure. The prospective cohort consisted of patients <18 years with structurally normal hearts and non-pre-excited supraventricular arrhythmias, who had an ablation in our centre from 2013 to 2018. The cohort was evaluated with the PedsQL™ 4.0 Generic Core Scales self-questionnaire prior to and post-ablation. The final cohort included 88 patients consisted of 52 males (59%), with a mean age at ablation of 12.5 ± 3.3 years. Forty-two patients (48%) had a retrograde-only accessory pathway mediating the tachycardia, 38 (43%) had atrio-ventricular nodal re-entrant tachycardia, 7 (8%) had ectopic atrial tachycardia, and 1 (1%) had atrial flutter. The main reason for an ablation was the patient's choice in 53%. There were no severe complications. Comparison between the baseline and post-ablation assessments showed that patients reported significant improvement in the scores for physical health, emotional and social functioning, as well as in the total scores. The present study demonstrates that the successful treatment of supraventricular arrhythmias by means of an ablation results in a significant improvement in the quality of self-reported life scores in young patients.

Электрофизиологические особенности и возможности аблации эктопических предсердных тахикардий из области некоронарной створки аортального клапана

Электрофизиологические особенности и возможности аблации эктопических предсердных тахикардий из области некоронарной створки аортального клапана

Severe congenital RYR1-associated myopathy complicated with atrial tachycardia and sinus node dysfunction: a case report

BackgroundCardiac arrhythmias are sometimes encountered in patients with hereditary myopathies and muscular dystrophies. Description of arrhythmias in myopathies and muscular dystrophies is very important, because arrhythmias have a strong impact on the outcomes for these patients and are potentially treatable.Case presentationA girl with severe congenital RYR1-related myopathy exhibited atrial tachycardia and sinus node dysfunction during infancy. She was born after uncomplicated caesarian delivery. She showed no breathing, complete ophthalmoplegia, complete bulbar paralysis, complete facial muscle paralysis, and extreme floppiness. At 5 months old, she developed persistent tachycardia around 200–210 beats per minutes. Holter monitoring revealed ectopic atrial tachycardia during tachyarrhythmia and occasional sinus pauses with junctional escape beats. Propranolol effectively alleviated tachyarrhythmia but was discontinued due to increased frequency and duration of the sinus pauses that led to bradyarrhythmia. There was no evidence of structural heart diseases or heart failure. The arrhythmia gradually resolved spontaneously and at 11 months old, she showed complete sinus rhythm.ConclusionsAlthough supraventricular arrhythmia is sometimes encountered in congenital myopathies, this is the first report of cardiac arrhythmia requiring drug intervention in RYR1-associated myopathy.

Arrhythmias in patients with pulmonary hypertension and chronic lung disease

Pulmonary arterial hypertension (PAH) occurs in 1% of the global population and can be divided in different disease groups. Pathophysiological aspects leading to supraventricular arrhythmias in these patients are due to increased pulmonary and right atrial pressure, increased activity of the sympathetic nervous system leading to right atrial electrical remodeling and ischemia in the right atrium. In the clinical setting these patients present with atrial flutter, atrial fibrillation or with ectopic atrial tachycardia. Regarding ventricular tachycardia there is alack of data. Occurrence of arrhythmia in these patients leads to adeterioration of PAH, so rhythm control should be the aim. This can be achieved by right atrial ablation, especially in patients presenting with atrial flutter; electric cardioversion or antiarrhythmic drug therapy are without definite guideline recommendations since there are too few clinical trials. Ablation with a transseptal approach in the left atrium is considered rather dangerous and should be avoided. Regarding arrhythmias in patients with chronic lung disease, few data are available. For patients with chronic obstructive pulmonary disease (COPD), there are good data available. These patients often suffer from coronary heart disease, atrial fibrillation, and ventricular tachycardia. Beta-blockers play an important role in COPD patients, even during exacerbation. Interventional therapies are safe but the arrhythmogenic foci often located outside of the pulmonary veins (in the right atrium).

Abstract 17376: Risk of Early Reablation Post Cryoballoon Ablation

Introduction: Post-ablation radiofrequency tissue friability has been described; however, tissue friability post cryoablation has not been well studied. We report a case of left atrial perforation with normal contact force radiofrequency ablation 22 days after initial cryoballoon ablation. Description: A 59-year-old male with persistent atrial fibrillation, severe biatrial enlargement, non-ischemic cardiomyopathy (EF of 20%), underwent initial cryoballoon pulmonary vein isolation with left atrial roof cryoablation with restoration of sinus rhythm and no complications. Patient presented 22 days later with sustained atrial flutter and heart rate over 130 bpm refractory to aggressive medical management, cardioversion, and acute on chronic congestive heart failure. Early re-ablation was performed with electrophysiology study and 3D activation map confirming ectopic atrial tachycardia foci arising from left atrial roof, anterior to the border of previously cryo-ablated region. St. Jude TactiCath™ contact force ablation catheter, was used to ablate this foci, and termination within 5 seconds of ablation was observed. Using the Force-Time Integral index to guide further ablation, the surrounding area was ablated for an additional 20 seconds at 30 W with a maximum recorded contact force throughout the procedure of 35 grams, and an average of 10-15 grams.A decrease in systolic blood pressure from 120 mmHg to 80 mmHg was noted, and intracardiac ultrasound confirmed 1.5 cm of pericardial effusion. Successful pericardiocentesis and reversal of anticoagulation was performed with ongoing bleeding, and eventual surgical intervention was required. On direct visualization during surgery, the left atrial roof perforation was confirmed, and was noted to be very friable and difficult to retain suture for repair. Patient did well post-operatively and was discharged with no recurrence of arrhythmias. Conclusions: Despite standard of care monitoring, including force-time integral index and contact-sensing catheters, atrial perforation occurred likely due to increased tissue friability post initial cryoablation. The optimal timing for repeat ablation is not completely understood, and extreme caution and avoidance of early re-ablation risk is prudent.

Случай успешной радиочастотной аблации очагов эктопических предсердных тахикардий левого предсердия и аблации левого заднебокового дополнительного предсердно-желудочкового соединения

Случай успешной радиочастотной аблации очагов эктопических предсердных тахикардий левого предсердия и аблации левого заднебокового дополнительного предсердно-желудочкового соединения

Predictors of Pharmacological Therapy of Ectopic Atrial Tachycardia in Children.

Ectopic atrial tachycardia (EAT) is a relatively common type of supraventricular tachycardia in the pediatric population, and it can be resistant to antiarrhythmic drugs and lead to tachycardia-induced cardiomyopathy (TIC) if not properly managed. The purpose of this study was to determine the predictors of the response to pharmacological therapy in children with EAT. From January 2009 to April 2014, 115 children were admitted to our hospital with a diagnosis of EAT and placed on antiarrhythmic drugs. We examined the clinical history, response to therapy, and follow-up of the children. The incidence of TIC secondary to EAT was 22.6% (n=26) in children. Incessant EAT accounted for 44.3% of all patients. Control of EAT with antiarrhythmic therapy was achieved in 73.9% (n=85) of the children. The combination of sotalol and propafenone performed well in controlling EAT in children [complete control in 35 (49.3%) of 71]. The mean time of conversion to sinus rhythm was 24days, and the mean duration of therapy was 11months in children with resolution. Multivariate predictors of the control of EAT were age at presentation (OR 0.289, P=0.038) and tachycardia type (OR 0.276, P=0.006). TIC occurs in 22.6% of children with EAT. Incessant EAT is more frequently complicated by TIC. Independent factors associated with a good response to pharmacological therapy include a younger age at presentation and non-incessant tachycardia in children with EAT.

Influence of total flavonoids derived from Choerospondias axillaris folium on aconitine-induced antiarrhythmic action and hemodynamics in Wistar rats

ABSTRACTIt is well known that various traditional Chinese medicines produce antiarrhythmic actions. The aims of this study were to examine whether total flavones derived from Choerospondias axillaris folium (TFCF) also produced antiarrhythmic effects using a rat model of aconitine-induced arrhythmia and to compare these observations with the effects of total flavones of Choerospondias axillaris fructus (TFC). Wistar rats were orally administered TFC (0.2 g/kg) or TFCF (0.1, 0.2, or 0.4 g/kg) daily for 7 d. Subsequently, aconitine iv at 25 µg/kg was used to induce arrhythmia in these animals. Control (C) physiological saline and positive verapamil rats were also administered orally. The starting times of ventricular ectopic beats (VE), ventricular tachycardia (VT), ventricular fibrillation (VF), and heart arrest (HA) were recorded. In comparison to C, TFCF and TFC significantly prolonged the starting time of VE, VT, VF, and HA induced by aconitine. With respect to hemodynamics, TFC and high-dose TFCF were effective in reducing HR without associated changes in BP in all groups. TFC and TFCF decreased left ventricular systolic pressure (LVSP) and maximal velocity rate of ventricular pressure (+dp/dt max and –dp/dt min) with no marked effect on left ventricular end diastolic pressure (LVEDP) and –dp/dtmin. Data demonstrated that TFCF and TFC were equally effective in diminishing the aconitine-mediated arrhythmias. In addition, TFCF and TFC produced a similar reduction in HR with no accompanying change in BP. These findings indicate that the TFCF- and TFC-induced alterations may be attributed to inhibition of ventricular contraction without altering ventricular diastolic function.

Intermediate-Term Results After Extracardiac Conduit Fontan Palliation in Children and Young Adults with Single Ventricle Physiology-A Single-center Experience.

The Fontan operation and its modifications are currently the standard palliation in patients with single ventricle physiology. The advantages of extracardiac conduit Fontan operation (ECF) have previously been described. We evaluated the outcome of patients who underwent ECF operation at our center since the year 2000 to assess morbidity, mortality and New York Heart Association (NYHA) functional class in the current era. Medical records of 97 patients who underwent ECF operation from November 2000 till October 2013 were reviewed to determine the diagnosis, age at surgery, surgical technique, postoperative complications, NYHA class at last follow-up, echocardiographic parameters, and most recent Holter monitor results. The median age at surgery was 3.4years with 4 total deaths until last follow-up (hospital mortality was 1%, and mortality after hospital discharge was 3%). Seventy-eight of the 97 patients (80%) underwent fenestrated Fontan surgery. Median duration of follow-up was 3.9years (IQR 0.2-12.2years). At the latest follow-up, 62 patients (67%) were determined to be in NYHA class I, 25 patients (27%) in NYHA class II, and 6 (6%) patients in NYHA class III, and the median oxygen saturation was 92% (IQR 86-96). There were 15 patients with history of preoperative arrhythmias and 6 of them required pacemaker placement at the time of surgery. One patient developed ectopic atrial tachycardia, and 1 patient had clinical thromboembolism on follow-up. Systolic function of the single ventricle by transthoracic echocardiogram at the latest follow-up was described as normal in 77 patients (83%), fair in 15 patients (16%), and poor in 1 patient (1%). The results of our study show that patients who undergo extracardiac conduit Fontan operation in the modern era may have significantly less morbidity and mortality when compared to earlier years.

Four years spectrum of ectopic atrial tachycardias following invasive cardiac electrophysiologic studies

Background: Cardiac electrophysiologic study and radiofrequency ablation have become an established mode of treatment for patients with refractory arrhythmias. These procedures are carried out regularly at the cardiac catheterization laboratory of Madras Medical Mission India. Objective: The purpose of this study was to evaluate our experience with cardiac electrophysiologic studies (EPS) and radiofrequency catheter ablations (RFA) of ectopic atrial tachycardias (AT). Materials and Methods: This was a retrospective study carried out in the Cardiac Electrophysiology Department, of the Institute of Cardiovascular diseases, Madras Medical Mission, India. All cases diagnosed to have ectopic AT following cardiac EPS between January 2010 and April 2014 were selected for study. The records, which were obtained from the cardiac electrophysiology clinical research office of Madras Medical Mission, were reviewed. 73 cases were chosen for analysis, using SPSS statistical software version 15. Results: There were 73 patients, comprised 31 males and 42 females. The mean age was 47.38 years. Commonly associated diseases were diabetes mellitus 16 (21.9%), hypertension 14 (19.1%), coronary heart disease 12 (16.5%) and congenital heart disease 8 (11%). The most common locations of AT were coronary sinus Ostial region 7 (14.0%), parahisian region 6 (12.0%) and crista terminaris region 4 (8.0%). Ablation was successful in 43 (84.3%). Complication rate was 4.11%. Conclusions: Treatment of ectopic AT by RFA is highly effective and safe.

Understanding the ECG. Part 3: Arrhythmias

In this third article of the British Journal of Cardiac Nursing’s ECG series, we will examine arrhythmias caused by abnormal impulse generation. The intention is not to explain every possible rhythm disturbance, but rather to review the most common and clinically relevant arrhythmias, and describe how they can be recognised on the ECG. We will also place each arrhythmia in clinical context by briefly discussing why it occurs, and how it is treated. Hopefully this process will illustrate the mechanisms that cause arrhythmias, and deepen the reader’s understanding of the electrical function of the heart. The rhythm disturbances that we will cover in this article are as follows:  Ectopic beats  Atrial fibrillation (AF) and flutter  Supraventricular tachycardia (SVT)  Ventricular tachycardia (VT)  Ventricular fibrillation (VF)

SLOW/SLOW TYPE OF ATRIOVENTRICULAR NODAL REENTRANT TACHYCARDIA IN FIRST DEGREE ATRIOVENTRICULAR BLOCK

The report describes the case of slow/slow type of atrioventricular nodal reentrant tachycardia in first degree atrioventricular block which simulate atrial ectopic or orthodromic tachycardia. Differential diagnosis technique is described and mechanisms of the phenomenon are illustrated.

Hypertrophic Cardiomyopathy and Implantable Defibrillators in Sweden: Inappropriate Shocks and Complications Requiring Surgery.

The expanded use of implantable cardioverter-defibrillators (ICDs) to prevent sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM) based on risk stratification in individuals without known previous ventricular arrhythmia is justified by an acceptable risk of device-related adverse events. Such complications, leading to surgical procedures or inappropriate electrical shocks, may impact mortality, morbidity, quality of life, and cost-effectiveness. From the Swedish ICD Registry, implants due to HCM since 1995 until November 2012 in patients aged ≥18 years were identified and medical records reviewed. Inappropriate ICD shock occurred in 14.3% (46 of 321 patients; mean follow-up 5.4 years) with a recurrent episode in 28.2% of them. In multivariable analysis, hazard ratio (HR) for atrial fibrillation was 3.5 (95% confidence interval 1.8-6.8; P < 0.001) but showed no significant association to male sex (HR = 0.77), age (HR = 0.99), secondary indication (HR = 1.02) or device, ICD-DR/CRTD vs. ICD-VR (HR 1.07). Inappropriate shocks were triggered by atrial fibrillation/flutter or ectopic tachycardia (56.5%), sinus tachycardia (14.5%), lead dysfunction (14.5%), and T-wave oversensing (13.0%). A reintervention, besides elective device replacement, occurred in 92 patients (totally 150 procedures). The majority were lead-related (70.0%) procedures, especially of the ICD lead. Reintervention was associated with female sex (HR = 1.6 P = 0.04). Inappropriate ICD shock triggered by atrial arrhythmias, lead dysfunction, or complications requiring surgical interventions, is a concern in HCM patients who will be eligible for long-term prevention of sudden death. Efforts to avoid adverse events and provide balanced risk-benefit information are important, especially in primary prevention.

Clinical course and treatment of ectopic atrial tachycardia in 144 children

Ectopic atrial tachycardia (EAT) is a common type of supraventricular tachycardia in pediatric population, and it can be resistant to antiarrhythmic drugs and lead to tachycardia induced cardiomyopathy (TIC) if not properly managed. This study assessed the clinical course and response to treatment of EAT in children. A retrospective review included 144 children at the First Hospital of Tsinghua University diagnosed with EAT from January 2009 to April 2014. The clinical detailed history, 12 lead ECG, 24-h Holter recording, echocardiography, response to therapy and follow-up were analyzed. The onset of EAT occurred at any age with a distribution with positive skewness, 57 children ≤1 years, 22 children > 1 - 3 years, 25 children > 3 - 6 years and 40 children ≥ 6 years of age. The percentages of the three tachycardia types were 36. 1% (n = 52) for incessant EAT, 52. 8% (n = 76) for paroxysmal EAT and 11. 1% (n = 16) for sporadic EAT, respectively. There were 115 patients received drug therapy in our hospital and in 72 cases the EAT was completely controlled. Antiarrhythmic therapy had been discontinued in 35 children with complete control. Normal sinus rhythm was observed by telemetry or Holter within 4 to 90 days and the mean duration of medical therapy was 310 days (range 15 to 608 days) in these children. The combination of sotalol and propafenone showed better effectiveness for control of children with EAT (54%, 41/76), compared with single sotalol (36%, 24/66) and the combination of amiodarone and metoprolol (30%, 7/23) (χ2 = 6. 296, P = 0. 043). Tachycardia type was able to predict the response to antiarrhythmic drugs for children with EAT, sporadic tachycardia had best control rate on pharmacological therapy compared with paroxysmal tachycardia and incessant tachycardia (94% (15/16) vs. 67% (42/63) vs. 42% (15/36), χ2 = 17. 925, P = 0. 000) . Acute success of radiofrequency ablation (RFA) in children who showed poor response to antiarrhythmic drugs was achieved in 45 of 49 (92%), ultimate success was achieved in 33 of 49 (67%). The incidence of TIC secondary to EAT was 18. 1% (n =26), and left ventricular ejection-fraction (LVEF) returned to normal in 23 children after successful control of EAT ((61 ± 4) % vs. (43 ± 5) %, t = - 10. 036, P = 0. 000). Side effects including abnormal thyroid function (in 3) and abnormal liver function (in 1) occurred in 4 (17%) of 23 children who received amiodarone and disappeared when amiodarone was discontinued. EAT in children predominantly occurred in young infants and children. Incessant EAT comprised a great percentage. The combination of sotalol and propafenone provided the best results for control of children with EAT. RFA should be considered as a preferred treatment for older children who displayed poor response to medical therapy.

Diagnosis of Arrhythmias in Athletes Using Leadless, Ambulatory HR Monitors

Exercise-related palpitations, vertigo, and syncope may be caused by benign etiologies but can also herald life-threatening arrhythmias. The precise diagnosis of these findings is therefore essential and potentially life saving but often is a challenge for sports physicians and cardiologists. Leadless, ambulatory HR monitors with chest strap transmitters have been designed to steer exercise intensity in athletes with a baseline sinus rhythm. However, they also can capture arrhythmias. Presented here are three cases of varying arrhythmias: atrial fibrillation, atrioventricular nodal reentrant tachycardia, and ectopic atrial tachycardia that demonstrate the utility of HR monitors designed for athletic purposes in facilitating the diagnosis of arrhythmias and guiding appropriate treatment.

Focal Left Atrial Tachycardia in a Patient with Left Ventricular Noncompaction

Left ventricular noncompaction (LVNC) is a rare disease caused by intrauterine failure of the myocardium to compact. The major clinical manifestations of LVNC include heart failure, ventricular tachyarrhythmia, thromboembolic event, and sudden deaths. Atrial arrhythmia usually seen is atrial fibrillation. We report a rare case of focal left atrial tachycardia in an 18-year-old patient who presented for evaluation of persistent tachycardia. Transthoracic echocardiogram showed severe systolic dysfunction and evidence of noncompaction of the left ventricle. A detailed review of ECG revealed the possibility of ectopic atrial tachycardia, most likely originating from the left side. Electrophysiology study showed sustained atrial tachycardia originating on the ridge anterior to the left sided pulmonary veins. A successful radiofrequency catheter ablation was performed at this site without any complications.

Psychiatric Disorder and Incessant Tachyarrhythmia in a Child

The case of a 14-year-old female with ectopic atrial tachycardia who had been followed for a history of anxiety and depression is presented. The patient was admitted to the intensive care unit after she attempted suicide, at which point there was electrocardiographic evidence of the atrial arrhythmia. During subsequent invasive electrophysiology study, a focus near the tricuspid annulus was localized and targeted for ablation, followed by resolution of the psychiatric symptoms. The case highlights the overlap between psychiatric complaints and true cardiac arrhythmia. A review of the literature is presented, with a special emphasis on distinguishing these two entities as well as a synopsis of this uncommon arrhythmia in the pediatric population.

周術期心房頻拍に対してデクスメデトミジン塩酸塩が有用であった2乳幼児例

周術期心房頻拍に対してデクスメデトミジン塩酸塩が有用であった2乳幼児例

Fetal and Neonatal Supraventricular Tachyarrhythmias

Several types of supraventricular tachyarrhythmias can occur in the fetus and neonate, including premature atrial contractions, ectopic atrial tachycardia, atrial flutter, and supraventricular tachycardia. This review describes the pathophysiology and corresponding electrocardiographic findings of each arrhythmia. In addition, this summary compares the clinical findings, management, and outcomes of these arrhythmias during fetal and postnatal life. The distinctive characteristics of ectopic and re-entrant tachycardias are also described.