Efficacy of antiarrhythmic drugs in adults with congenital heart disease and supraventricular tachycardias

Review of rhythm disturbances in patient after fontan completion: epidemiology, management, and surveillance

Purpose

The Fontan operation is commonly associated with alterations in heart rhythms, both tachycardic and bradycardic. Despite modifications to attempt to mitigate these complications, arrythmias still frequently occur. The purpose of this review is to examine the literature regarding the scope of the problem, therapeutic options, and current recommendations regarding screening and surveillance.

Recent findings

Modifications to the original Fontan procedure, antiarrhythmic medications, and improvements in catheter ablation procedures have improved the management of patients with arrhythmias following Fontan palliation. There is growing interest in the role of junctional rhythm in the role of Fontan dysfunction. While chronotropic incompetence has often been blamed for poor exercise testing, there is evidence that decreased performance may be related to ventricular filling and Fontan hemodynamics.

Summary

Tachyarrhythmias are an important cause of mortality and morbidity after the Fontan operation. Prompt and aggressive management of arrhythmias with the goal of maintaining sinus rhythm is vital. Management strategies such as anti-arrhythmic medications, ablation, anti-tachycardia pacing and Fontan conversion should be seen as complementary and used early to prevent hemodynamic deterioration. Bradyarrythmias likely also contribute to Fontan failure. Pacing is the primary management strategy with evidence supporting use of atrial pacing. However, ventricular pacing seems to often lead to deleterious effects. Current guidelines recommend surveillance with Holter monitor every 2-3 years in adolescents and every 1-2 years in adults. Future directions for research include further assessment of junctional rhythm and its management as well as further identifying patients in which pacing would be beneficial.

[Cardiac arrhythmias in adults with congenital heart disease]

In patients with congenital heart disease, cardiac arrhythmias are complex and require a thorough understanding of the anatomy, past surgical and interventional procedures, and the specific electric processes. Supraventricular tachycardias commonly present as emergency situations and should be treated immediately, particularly when there is an underlying complex malformation. Establishing sinus rhythm is usually superior to pure frequency control for hemodynamic reasons. Catheter ablation should be preferred over medical treatment, even though several procedures are often necessary. In addition, bradycardia is seen more frequently in congenital heart defects; this could be aggravated by antiarrhythmic drugs. There are significant differences between the indications and techniques used for pacemaker implantation in patients with congenital heart defects and those without. Patients with complex congenital heart diseases have an increased risk of thromboembolism; therefore, an individual and early indication for low-threshold oral anticoagulation is necessary; direct oral anticoagulants can also be used for this purpose. In risk stratification for sudden cardiac death, the principles of general guidelines are often not applicable, and individualized decisions are required. Recently, a new general risk score for congenital heart disease has been developed. The treatment of cardiac arrhythmias in patients with congenital heart disease should always be performed in close cooperation with specialized centers.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Patients With Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

Cardiac Drugs in ACHD Cardiovascular Medicine

Adult congenital heart disease (ACHD) is a growing population that requires life-long care due to advances in pediatric care and surgical or catheter procedures. Despite this, drug therapy in ACHD remains largely empiric due to the lack of clinical data, and formalized guidelines on drug therapy are currently lacking. The aging ACHD population has led to an increase in late cardiovascular complications such as heart failure, arrhythmias, and pulmonary hypertension. Pharmacotherapy, with few exceptions, in ACHD is largely supportive, whereas significant structural abnormalities usually require interventional, surgical, or percutaneous treatment. Recent advances in ACHD have prolonged survival for these patients, but further research is needed to determine the most effective treatment options for these patients. A better understanding of the use of cardiac drugs in ACHD patients could lead to improved treatment outcomes and a better quality of life for these patients. This review aims to provide an overview of the current status of cardiac drugs in ACHD cardiovascular medicine, including the rationale, limited current evidence, and knowledge gaps in this growing area.

Early and Late Postoperative Tachyarrhythmias in Children and Young Adults Undergoing Congenital Heart Disease Surgery

The population of patients with congenital heart disease is constantly growing with an increasing number of individuals reaching adulthood. A significant proportion of these children and young adults will suffer from tachyarrhythmias due to the abnormal anatomy, the hemodynamic burden, or as a sequela of surgical treatment. Depending on the underlying mechanism, arrhythmias may arise in the early postoperative period (hours to days after surgery) or in the late postoperative period (usually years after surgery). A good understanding of the electrophysiological characteristics and pathophysiological mechanisms is therefore crucial to guide the therapeutic approach. Here, we synthesize the current state of knowledge on epidemiological features, risk factors, pathophysiological insights, electrophysiological features, and therapy regarding tachyarrhythmias in children and young adults undergoing reparative surgery for congenital heart disease. The evolution and latest data on treatment options, including pharmacological therapy, ablation procedures, device therapy decision, and thromboprophylaxis, are summarized. Finally, throughout this comprehensive review, knowledge gaps and areas for future research are also identified.

Treating Supraventricular Tachycardia With Amiodarone in a Patient With Ebstein's Anomaly

Ebstein's anomaly is a congenital deformity marked by disease of the tricuspid valve and right cardiac hypertrophy. The severity, morphology, and appearance of Ebstein's anomaly cases might vary greatly. We discuss a case of an eight-year-old child with Ebstein's anomaly who presented with supraventricular tachycardia and was effectively treated with amiodarone after initial treatment with adenosine failed to reduce the heart rate.

Risk Factors for Atrial Arrhythmias in Adults With Ebstein Anomaly

Background

Atrial arrhythmias (AA) are common in Ebstein anomaly (EA), but risk factors associated with AA are not well understood.

Objectives

The purpose of this study was to determine the prevalence and risk factors for AA at baseline, incidence, and risk factors for AA during follow-up.

Methods

Adults with EA receiving care at Mayo Clinic, MN, between 2003 and 2020 were included. AA was defined as atrial fibrillation (AF) or atrial flutter/tachycardia (AFL). Clinical, echocardiographic, rhythm, surgical data were collected.

Results

Of 682 patients (aged 36 [24-49] years), 235 (34%) had AA at baseline (126 [18%] AF and 144 [21%] AFL), and the risk factors for AA were age, left and right atrial volume indexes, and reservoir strain. Among 447 patients without AA, 10-year cumulative incidence of AF and AFL was 16% and 22%, respectively. The risk factors for incident AF were older age and right atrial reservoir strain. The risk factors for incident AFL were atrial septal defect, left atrial volume index, and male sex. Among patients with baseline AA, 129 (40%) had recurrent episodes (AF 63 [20%], AFL 78 [24%]). The 5-year recurrence rate of AA was 34%, without significant difference for AF vs AFL (46% vs 27%, P = 0.081). Older age and right atrial reservoir strain were associated with recurrent AF.

Conclusions

Patients with EA are at risk for incident and recurrent AA. AF was almost as common as AFL despite relatively young ages. Echocardiographic indexes of atrial function can identify at-risk patients, hence be used to improve risk stratification and guide therapy.

Thyroid Dysfunction under Amiodarone in Patients with and without Congenital Heart Disease: Results of a Nationwide Analysis

Background: Amiodarone has a profound adverse toxicity profile. Large population-based analyses quantifying the risk of thyroid dysfunction (TD) in adults with and without congenital heart disease (ACHD) are lacking. Methods: All adults registered with a major German health insurer (≈9.2 million members) with amiodarone prescriptions were analyzed. Occurrence of amiodarone-associated TD was assessed. Results: Overall, 48,891 non-ACHD (37% female; median 73 years) and 886 ACHD (34% female; median 66 years) received amiodarone. Over 184,787 patient-years, 10,875 cases of TD occurred. The 10-year risk for TD was 38% in non-ACHD (35% ACHD). Within ACHD, compared to amiodarone-naïve patients, the hazard ratio (HR) for TD was 3.9 at 4 years after any amiodarone exposure. TD was associated with female gender (HR 1.42, p < 0.001) and younger age (HR 0.97 per 10 years, p = 0.009). Patients with congenital heart disease were not at increased risk (HR 0.98, p = 0.80). Diagnosis of complex congenital heart disease, however, was a predictor for TD (HR 1.56, p = 0.02). Amiodarone was continued in 47% of non-ACHD (38% ACHD), and 2.3% of non-ACHD (3.5% ACHD) underwent thyroid surgery/radiotherapy. Conclusions: Amiodarone-associated TD is common and comparable in non-ACHD and ACHD. While female gender and younger age are predictors for TD, congenital heart disease is not necessarily associated with an elevated risk.

Tachykarde Rhythmusstörungen bei EMAH – Aspekte der katheterinterventionellen Therapie

Tachykarde Rhythmusstörungen bei Erwachsenen mit angeborenem Herzfehler (EMAH) haben großen Einfluss auf Morbidität und Letalität dieser Patientengruppe. Sie basieren in der Mehrzahl auf erworbenen Substraten, die eine typische Langzeitfolge des angeborenen Herzfehlers (AHF) insbesondere nach herzchirurgischen Eingriffen darstellen. Antiarrhythmika können akut effektiv eingesetzt werden, sind aber als langfristige Behandlungsstrategie meist wenig verlässlich zur Unterdrückung von Tachykardierezidiven. Zusätzlich können Kontraindikationen bestehen bei eingeschränkter Ventrikelfunktion, hämodynamischen Rest-Fehlbelastungen, bradykardem Grundrhythmus sowie Arzneimittelnebenwirkungen. Vor diesem Hintergrund hat sich die katheterinterventionelle Ablationsbehandlung in den beiden letzten Jahrzehnten als Therapie der Wahl für die Mehrheit der Tachykardieformen bei EMAH mit zunehmend hohen Erfolgs- und niedrigen Komplikationsquoten etabliert.

"Second line medications" for supraventricular arrhythmias in children: In-hospital efficacy and adverse events during treatment initiation of sotalol and flecainide

INTRODUCTION

Sotalol and flecainide are used as second line agents in children for the treatment of supraventricular arrhythmias (SA) refractory to anti-beta adrenergic antiarrhythmics or digoxin. Efficacy and adverse events in this cohort have not been well described. Here, we report our institutional experience of second line treatment initiation for SA in children.

METHODS AND RESULTS

Utilizing an institutional database, 247 patients initiated on sotalol and 81 patients initiated on flecainide were identified. Congenital heart disease (CHD) was present in 40% of patients. Arrhythmia-free discharge on single or dual agent therapy (in combination with other antiarrhythmics) was 87% for sotalol and 91% for flecainide. Neither age, sex, dosing, presence of CHD nor arrhythmia subtype were associated with alterations in in-hospital efficacy. Compared to baseline, QTc intervals in sotalol patients (436 [416-452 ms] vs. 415 [400-431 ms], p < .01) and QRS intervals in flecainide patients (75 [68-88 ms] vs. 62 [56-71 ms], p < .01) were prolonged. Dose reduction or discontinuation due to QRS prolongation occurred in 9% of patients on flecainide. QTc prolongation resulting in dose reduction/discontinuation of sotalol was encountered in 9 patients (4%) and death with documented torsade de pointes in 2 patients (1%), with 9 of 11 patients having underlying CHD.

CONCLUSION

In children requiring second line agents for treatment of SA, both sotalol and flecainide appear to be highly efficacious. Although predominantly safe in otherwise healthy patients, electrocardiogram changes can occur and children with underlying cardiac disease may have an increased risk of adverse events and rhythm-related side effects during initiation.

Therapy of supraventricular and ventricular arrhythmias in adults with congenital heart disease-narrative review

Arrhythmias are among the most common late complications in adults with congenital heart disease (ACHD) and a frequent reason for hospital admission. Both, supraventricular and ventricular arrhythmias, not only cause debilitating symptoms, but may be life-threatening by increasing risk of stroke, causing or worsening heart failure and being associated with sudden death. Substrate and risk for arrhythmia differs widely between congenital defects with specific arrhythmias being much more common in some patients than others. Atrial macroreentrant arrhythmias are particularly frequent in patients with atrial septal defects and repair that involves atrial incisions including patients with transposition of the great arteries (TGA) and atrial switch. Accessory pathways and related arrhythmias are often associated with Ebstein's anomaly and congenitally corrected TGA. Monomorphic ventricular arrhythmias occur in patients with ventricular incisions, namely patients with Tetralogy of Fallot. Changes in surgical repair techniques influence arrhythmia prevalence and substrate as well as anatomical access for catheter ablation procedures. In addition, epidemiologic changes associated with improved long-term survival will further increase the prevalence of atrial fibrillation in ACHD. This article summarizes current understanding of prevalence of specific arrhythmias, underlying mechanisms, medical and interventional treatment options and their outcome in ACHD.

Atrial Fibrillation in Congenital Heart Disease

The increasing prevalence of AF in a growing population of adults with congenital heart disease (CHD) poses new challenges to clinicians involved in the management of these patients. Distinctive underlying anatomies, unique physiological aspects, a high diversity of corrective surgeries and associated comorbidities can complicate clinical decision-making. In this review, the authors provide an overview of the current knowledge on epidemiology and pathophysiology, with a special focus on the differences to the non-CHD population and the clinical impact of AF in adults with CHD. Acute and long-term management strategies are summarised, including the use of antiarrhythmic drugs, catheter or surgical ablation and prophylaxis of thromboembolism. Finally, gaps of knowledge and potential areas of future research are highlighted.

Extrasystoles in adults with congenital heart disease: treatment options

The prevalence of congenital heart disease (CHD) is estimated to be almost one in 100 newborns, with > 90% of patients with CHD surviving into adulthood due to medical and surgical advances in recent decades. The rationale for treatment of ventricular premature beats (VPBs) in the general population without underlying structural heart disease is mainly based on the presence of symptoms and/or the risk for developing VPB-induced cardiomyopathy in patients with very frequent VPBs. In CHD, the same general principles apply, but the clinical picture is often more complicated due to the presence of symptoms and/or systolic dysfunction resulting from the underlying heart disease itself. Sudden cardiac death due to ventricular arrhythmias is a major concern in the CHD population, although its incidence is relatively low (<0.1%/year). Beta-blockers are the first-line medical treatment for CHD patients with VPBs, although no dedicated studies are available on the use of beta-blockers or anti-arrhythmic drugs in patients with CHD for this indication. Catheter ablation has evolved in recent years as an important treatment modality for cardiac arrhythmias, generally showing superior efficacy over medical treatment for most types of arrhythmias. However, recent technological advances have led to improved methods for ablation even in complex underlying anatomical substrates, with possibilities for image fusion between three-dimensional imaging modalities and electroanatomical mapping systems during the procedure. In addition to a discussion of the above, the article also presents two examples of VPB ablation in CHD patients.

General management of pulmonary arterial hypertension associated with adult congenital heart disease

Over the past 15 years there have been significant improvements in the treatment of pulmonary arterial hypertension due to congenital heart disease. Patients now live for several decades, but morbidity and mortality remain high. This article describes the holistic management of this patient group with an emphasis on both the physical and psychosocial aspects of care, taking into account the consequences of chronic cyanosis, avoiding complications and improving quality of life.

Management of tachyarrhythmias in pregnancy - A review

The most common arrhythmias detected during pregnancy include sinus tachycardia, sinus bradycardia, and sinus arrhythmia, identified in 0.1% of pregnancies. Isolated premature atrial or ventricular arrhythmias are observed in 0.03% of pregnancies. Arrhythmias may become more frequent during pregnancy or may manifest for the first time.

The 2020 Canadian Cardiovascular Society/Canadian Heart Rhythm Society Comprehensive Guidelines for the Management of Atrial Fibrillation

The Canadian Cardiovascular Society (CCS) atrial fibrillation (AF) guidelines program was developed to aid clinicians in the management of these complex patients, as well as to provide direction to policy makers and health care systems regarding related issues. The most recent comprehensive CCS AF guidelines update was published in 2010. Since then, periodic updates were published dealing with rapidly changing areas. However, since 2010 a large number of developments had accumulated in a wide range of areas, motivating the committee to complete a thorough guideline review. The 2020 iteration of the CCS AF guidelines represents a comprehensive renewal that integrates, updates, and replaces the past decade of guidelines, recommendations, and practical tips. It is intended to be used by practicing clinicians across all disciplines who care for patients with AF. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) system was used to evaluate recommendation strength and the quality of evidence. Areas of focus include: AF classification and definitions, epidemiology, pathophysiology, clinical evaluation, screening and opportunistic AF detection, detection and management of modifiable risk factors, integrated approach to AF management, stroke prevention, arrhythmia management, sex differences, and AF in special populations. Extensive use is made of tables and figures to synthesize important material and present key concepts. This document should be an important aid for knowledge translation and a tool to help improve clinical management of this important and challenging arrhythmia.

Adults with Congenital Heart Disease and Arrhythmia Management

Arrhythmia management in adult congenital heart disease (ACHD) encompasses a wide range of problems from bradyarrhythmia to tachyarrhythmia, sudden death, and heart failure-related electrical dyssynchrony. Major advances in the understanding of the pathophysiology and treatments of these problems over the past decade have resulted in improved therapeutic strategies and outcomes. This article attempts to define these problems and review contemporary management for the patient with ACHD presenting with cardiac arrhythmia.

Improvement in ventricular function with rhythm control of atrial arrhythmias may delay the need for atrioventricular valve surgery in adults with congenital heart disease

OBJECTIVE

Atrial arrhythmias and atrioventricular valve regurgitation (AVVR) are common causes of morbidity among adults with congenital heart disease (ACHD). The impact of rhythm control on AVVR in this population is unknown. We sought to determine whether a rhythm control strategy is associated with greater freedom from AV valve surgery than a rate control strategy.

DESIGN

Patients evaluated by both ACHD and electrophysiology specialists at a single academic center were screened for atrial arrhythmias and at least moderate-severe AVVR. Clinical and electrographic data were abstracted. All echocardiograms were interpreted by a single echocardiographer blinded to treatment strategy. Patients were followed until AV valve surgery, heart transplantation, death, or last clinical follow-up.

RESULTS

Rhythm control was attempted in 9 of 24 identified patients. Among these nine patients, arrhythmias were eliminated in three and reduced from persistent to paroxysmal in another three. In the rhythm control group, mean left ventricular ejection fraction improved from 54.4 ± 12.4% to 60.0 ± 11.5% (P = .02) and mean right ventricular systolic function increased nearly one grade (P = .02). AVVR did not decrease significantly. No significant change in left or right ventricular systolic function, or AVVR was observed among the 15 patients treated with rate control. Four-year survival free of AV valve operation and heart transplant was 88% in the rhythm control group and 31% in the rate control group (P = .04).

CONCLUSIONS

In ACHD patients with atrial arrhythmias and at least moderate-severe AVVR, a rhythm control strategy was associated with improved biventricular systolic function. This improvement in ventricular function and symptoms may allow valve surgery to be deferred.

Adults with congenital heart disease: ready for mobile health?

PURPOSE

Mobile health (mHealth) could improve the outcome of grown-up patients with congenital heart disease (GUCH) and reduce their emergency care utilisation. Inappropriate use of mHealth, however, can lead to data overload for professionals and unnecessary data collection for patients, increasing the burden for both. We aimed to determine the clinical characteristics of patients with high emergency care utilisation and to test whether these patients were willing to start using mHealth.

METHODS

Clinical characteristics and emergency care utilisation of consecutive GUCH patients who visited one of the two participating cardiologists at the outpatient clinic of the Academic Medical Centre in Amsterdam were studied retrospectively. All patients were approached to fill in an mHealth questionnaire. A frequency of three or more emergency visits in 5 years was defined as high emergency care utilisation.

RESULTS

In total, 202 consecutive GUCH patients who visited one of the two participating cardiologists were studied. Median age was 41 years, 47% were male, and 51% were symptomatic. In the previous 5 years, 134 emergency visits were identified. Of all patients, 8% had high emergency care utilisation. High emergency care utilisation was associated with patients being symptomatic, using antiarrhythmic drugs or diuretics. In total, 75% of all patients with high emergency care utilisation were willing to start using mHealth.

CONCLUSION

GUCH patients who are symptomatic, those on antiarrhythmic drug therapy and those on diuretics are suitable candidates for enrolment in future mHealth initiatives because of both high care utilisation and high motivation to start using mHealth.

eHealth in patients with congenital heart disease: a review

INTRODUCTION

Mobile health (mHealth), an advanced form of eHealth is expected to drastically change the field of traditional healthcare in the near future as wearables and mobile applications are rapidly increasing in number. The majority of patients with congenital heart disease (CHD) now reach adulthood and this relative young patient population seems particularly suited for mHealth, as they require lifelong follow-up, experience high morbidity burden, and were raised in this digital era. In patients with acquired heart disease the potential of eHealth has been demonstrated, yet data are still inconclusive. Areas covered: In this review of the current literature we evaluated the effect of various eHealth interventions in patients with CHD. Our search resulted in a mere 10 studies, which comprised mostly of children or adolescents with severe CHD. Home-monitoring of saturation and weight through mHealth was found to be beneficial in patients after palliation procedures, and video conferencing was found to have a positive effect on anxiety and healthcare utilization. Expert commentary: Due to high morbidity and mortality in patients with CHD and the promising results of eHealth interventions, further research is desperately needed.

Efficacy and adverse effects of sotalol in adults with congenital heart disease

INTRODUCTION

Adults with congenital heart disease (CHD) are predisposed to arrhythmias, which can often be refractory to medical therapy. Sotalol is an attractive alternative antiarrhythmic to amiodarone in this younger patient population, given the latter's toxicity profile, but it may have proarrhythmic effects. We therefore aimed to assess the efficacy and safety of sotalol in adults with CHD.

METHODS

We retrospectively assessed our adult CHD database for all patients ≥16 years old, with moderate to highly complex defects, who were prescribed sotalol between 2000 and 2017. Efficacy in treating the clinical arrhythmia was assessed as complete, partial or failure. Adverse effects, including proarrhythmia, were documented.

RESULTS

Sotalol was prescribed in 82 of 902 adult CHD patients reviewed (9%). The mean age at sotalol commencement was 31.8 ± 13.1 years, with a median time on sotalol of 2.8 years. The average prescribed dose was 122 ± 51 mg/daily. Sotalol was completely effective in 48% (n = 39), partially effective in 46% (n = 38) and failed to control the clinical arrhythmia in 6% (n = 5). Fifteen patients (18%) discontinued sotalol due to a side effect, most commonly fatigue or dyspnoea. No episodes of torsades de pointes or sudden cardiac death were observed. Significant bradycardia related to sotalol occurred in 13% (n = 11, with permanent pacing implemented in 4), and was associated with Fontan anatomy.

CONCLUSIONS

In moderate to highly complex adult CHD, sotalol was reasonably effective and safe in low doses. Side effects limiting treatment were typically non-life-threatening, with significant bradycardia related to sotalol more likely in Fontan patients.

Efficacy and Safety of Low-Dose Amiodarone Therapy for Tachyarrhythmia in Congenital Heart Disease

Amiodarone (AMD) is a class III anti-arrhythmic drug that is highly effective for tachyarrhythmia treatment. AMD is widely used in adults with congenital heart disease (CHD); however, higher doses of AMD (> 200 mg/day) can cause various non-cardiac side effects. The purpose of this study was to assess the efficacy, safety, and adverse events of low-dose AMD (≤ 200 mg/day) for tachyarrhythmia in patients with CHD. We retrospectively studied 80 patients with CHD and tachyarrhythmia who received oral low-dose AMD (≤ 200 mg/day) from January 2004 to March 2016. Low-dose AMD therapy was used to treat supraventricular tachycardia (SVT) in 51 patients and ventricular tachycardia (VT) in 29 patients. After a mean follow-up of 2.9 years for SVT and 3.2 years for VT, 36% and 65% of the patients with SVT and VT, respectively, were free from a first tachyarrhythmia recurrence for 3 years. The incidence of AMD-induced side effects was 23%, and all these cases consisted of thyroid dysfunction. Low-dose AMD was effective for the treatment of tachyarrhythmia in patients with CHD and had a relatively low incidence of side effects. These findings suggest that low-dose AMD is useful and effective for decreasing the frequency of tachyarrhythmia in patients with CHD and has a low incidence of side effects.

Long-Term Follow-Up After Ablation of Intra-Atrial Re-Entrant Tachycardia in Patients With Congenital Heart Disease: Types and Predictors of Recurrence

OBJECTIVES

The aim of this study was to analyze the long-term outcomes after intra-atrial re-entrant tachycardia (IART) ablation in congenital heart disease (CHD).

BACKGROUND

IART increases morbidity and mortality in CHD patients. Radiofrequency catheter ablation has evolved into the first-line treatment of this complication.

METHODS

This was a prospective, single-center study of all consecutive CHD patients who underwent first ablation for IART from January 2009 to December 2015 (n = 94, 39.4% female, age 36.55 ± 14.9 years, follow-up 44.45 ± 22.7 months).

RESULTS

During the study period, 130 procedures were performed (n = 94, 1.21 ± 0.41 IART/patient). In the first procedure, 114 IART were ablated (short-term success 74.66%). Forty-nine percent of the patients whose IART was ablated had non-cavotricuspid isthmus (CTI)-related IART (alone or with concomitant CTI IART). After the first ablation, 54.3% maintained sinus rhythm (SR), 23.9% presented with recurrence of the ablated IART, 14.2% developed new IART, and 7.6% presented with atrial fibrillation (AF). After the second radiofrequency catheter ablation, 78.3% were in SR, 8.7% presented with AF, and 23.0% presented with IART (50% new IART). Multivariate predictors of recurrences were non-CTI IART (hazard ratio [HR]: 5.06; 95% confidence interval [CI]: 1.6 to 15.9; p = 0.006), PR interval >200 ms (HR: 4.02; 95% CI: 1.9 to 11.3; p = 0.009), AF induction (HR: 3.11; 95% CI: 1.1 to 9.1; p = 0.04). and previous AF (HR: 3.08; 95% CI: 1.1 to 9.3; p = 0.04). A risk score according multivariate model identified 3 levels of recurrence risk: 5.8%, 20%, and 58.5% (area under the receiver-operating characteristic curve 0.8 ± 0.03; p < 0.0001).

CONCLUSIONS

Ablation of IART in CHD is a challenging procedure, but after ablation in experienced centers, SR can be maintained in 78.3%. Predictors of recurrences are non-CTI-related IART, long PR interval, and previous or induced AF. A risk score based on these factors can be useful for recurrence prediction.

Predictors of Acute Failure Ablation of Intra-atrial Re-entrant Tachycardia in Patients With Congenital Heart Disease: Cardiac Disease, Atypical Flutter, and Previous Atrial Fibrillation

BACKGROUND

Intra-atrial re-entrant tachycardia (IART) in patients with congenital heart disease (CHD) increases morbidity and mortality. Radiofrequency catheter ablation has evolved as the first-line treatment. The aim of this study was to analyze the acute success and to identify predictors of failed IART radiofrequency catheter ablation in CHD.

METHODS AND RESULTS

The observational study included all consecutive patients with CHD who underwent a first ablation procedure for IART at a single center from January 2009 to December 2015 (94 patients, 39.4% female, age: 36.55±14.9 years). In the first procedure, 114 IART were ablated (acute success: 74.6%; 1.21±0.41 IART per patient) with an acute success of 74.5%. Cavotricuspid isthmus-related IART was the only arrhythmia in 51%; non-cavotricuspid isthmus-related IART was the only mechanism in 27.7% and 21.3% of the patients had both types of IART. Predictors of acute radiofrequency catheter ablation failure were as follows: nonrelated cavotricuspid isthmus IART (odds ratio 7.3; confidence interval [CI], 1.9-17.9; P=0.04), previous atrial fibrillation (odds ratio 6.1; CI, 1.3-18.4; P=0.02), transposition of great arteries (odds ratio, 4.9; CI, 1.4-17.2; P=0.01) and systemic ventricle dilation (odds ratio 4.8; CI, 1.1-21.7; P=0.04) with an area under the receiver operating characteristic curve of 0.83±0.056 (CI, 0.74-0.93, P=0.001). After a mean follow-up longer than 3.5 years, 78.3% of the patients were in sinus rhythm (33.1% of the patients required more than 1 radiofrequency catheter ablation procedure).

CONCLUSIONS

Although ablation in CHD is a challenging procedure, acute success of 75% can be achieved in moderate-highly complex CHD patients in a referral center. Predictors of failed ablation are IART different from cavotricuspid isthmus, previous atrial fibrillation, and markers of complex CHD (transposition of great arteries, systemic ventricle dilation).

Drug Therapy in Adult Congenital Heart Disease

Adults with congenital heart disease are at risk for atrial and ventricular arrhythmias that can lead to an increased morbidity as well as mortality. When catheter ablation is not an option or unsuccessful, antiarrhythmic drugs are the mainstay of treatment. There is limited data on the use of antiarrhythmics in this population. The purpose of this article is to discuss the practical aspects of the use of antiarrhythmics in adults with congenital heart disease. Several tables have been provided to provide clinicians a reference for daily use.

Atrial tachyarrhythmia in adult congenital heart disease

The adult congenital heart disease (ACHD) population continues to grow and most cardiologists, emergency room physicians and family doctors will intermittently come into contact with these patients. Oftentimes this may be in the setting of a presentation with atrial tachyarrhythmia; one of the commonest late complications of ACHD and problem with potentially serious implications. Providing appropriate initial care and ongoing management of atrial tachyarrhythmia in ACHD patients requires a degree of specialist knowledge and an awareness of certain key issues. In ACHD, atrial tachyarrhythmia is usually related to the abnormal anatomy of the underlying heart defect and often occurs as a result of surgical scar or a consequence of residual hemodynamic or electrical disturbances. Arrhythmias significantly increase mortality and morbidity in ACHD and are the most frequent reason for ACHD hospitalization. Intra-atrial reentrant tachycardia and atrial fibrillation are the most prevalent type of arrhythmia in this patient group. In hemodynamically unstable patients, urgent cardioversion is required. Acute management of the stable patient includes anticoagulation, rate control, and electrical or pharmacological cardioversion. In ACHD, rhythm control is the preferred management strategy and can often be achieved. However, in the long-term, medication side-effects can prove problematic. Electrophysiology studies and catheter ablation are important treatments modalities and in certain cases, surgical or percutaneous treatment of the underlying cardiac defect has a role. ACHD patients, especially those with complex CHD, are at increased risk of thromboembolic events and anticoagulation is usually required. Female ACHD patients of child bearing age may wish to pursue pregnancies. The risk of atrial arrhythmias is increased during pregnancy and management of atrial tachyarrhythmia during pregnancy needs specific consideration.

Supraventricular Tachycardia in Adult Congenital Heart Disease: Mechanisms, Diagnosis, and Clinical Aspects

Supraventricular arrhythmias represent a major source of morbidity in adults with congenital heart disease (ACHD). Anatomic variants and post-operative changes contribute to a unique electrophysiologic milieu ripe for the development of supraventricular tachycardia. Intra-atrial reentrant tachycardia is the most prevalent mechanism. Atrioventricular reciprocating tachycardia is common in lesions associated with accessory pathways. Abnormal anatomy complicates the management of atrioventricular nodal reentrant tachycardia. Tachycardia mediated by twin atrioventricular nodes is rare. Focal tachycardias are considerations in the ACHD population. Each of these tachycardia mechanisms is reviewed, focusing on the inherent diagnostic and therapeutic challenges.

Supraventricular Arrhythmias in Patients with Adult Congenital Heart Disease

An increasing number of patients with congenital heart disease survive to adulthood; such prolonged survival is related to a rapid evolution of successful surgical repairs and modern diagnostic techniques. Despite these improvements, corrective atrial incisions performed at surgery still lead to subsequent myocardial scarring harbouring a potential substrate for macro-reentrant atrial tachycardia. Macroreentrant atrial tachycardias are the most common (75 %) type of supraventricular tachycardia (SVT) in patients with adult congenital heart disease (ACHD). Patients with ACHD, atrial tachycardias and impaired ventricular function - important risk factors for sudden cardiac death (SCD) - have a 2-9 % SCD risk per decade. Moreover, ACHD imposes certain considerations when choosing antiarrhythmic drugs from a safety aspect and also when considering catheter ablation procedures related to the inherent cardiac anatomical barriers and required expertise. Expert recommendations for physicians managing these patients are therefore mandatory. This review summarises current evidence-based developments in the field, focusing on advances in and general recommendations for the management of ACHD, including the recently published recommendations on management of SVT by the European Heart Rhythm Association.

Outcomes of Direct Current Cardioversion in Adults With Congenital Heart Disease

Few data exist on direct current cardioversion (DCCV) in adult patients with congenital heart disease (CHD). This is a retrospective case-control study of 279 adults with CHD and 279 adults without CHD (control group) who had elective DCCV for atrial arrhythmias at Mayo Clinic, 2001 to 2013. Control patients were matched by gender and arrhythmia type. The objective was to compare DCCV procedural failure (failure to terminate the presenting arrhythmia) and arrhythmia recurrence (AR). In the CHD group (mean age 55 ± 20 years; men 166 [59%]), the most common diagnosis was Fontan palliation (61; 22%). Transesophageal echocardiography was performed before DCCV in 216 patients (77%); 162 (58%) had atrial flutter, and 117 (42%) had atrial fibrillation. Procedural failure and AR between the case and the control groups were more common in the CHD group (14% vs 7%, p = 0.01) and (83% vs 66% at 60 months, p = 0.001) respectively. There were no deaths or thromboembolic complications. The multivariable risk factors for procedural failure were Fontan palliation and spontaneous echocardiographic contrast; the risk factors for AR were Fontan palliation and atrial fibrillation. When patients with Fontan palliation were excluded from the analysis, the outcome of DCCV (failure and recurrence rates) was similar for the CHD and non-CHD groups despite the age difference between the cohorts. In conclusion, the present study showed that DCCV outcomes were similar for CHD and non-CHD patients, with the exception of patients with Fontan palliation.

Mobile health in adults with congenital heart disease: current use and future needs

Objective

Many adults with congenital heart disease (CHD) are affected lifelong by cardiac events, particularly arrhythmias and heart failure. Despite the care provided, the cardiac event rate remains high. Mobile health (mHealth) brings opportunities to enhance daily monitoring and hence timely response in an attempt to improve outcome. However, it is not known if adults with CHD are currently using mHealth and what type of mHealth they may need in the near future.

Methods

Consecutive adult patients with CHD who visited the outpatient clinic at the Academic Medical Center in Amsterdam were asked to fill out questionnaires. Exclusion criteria for this study were mental impairment or inability to read and write Dutch.

Results

All 118 patients participated (median age 40 (range 18–78) years, 40 % male, 49 % symptomatic) and 92 % owned a smartphone. Whereas only a small minority (14 %) of patients used mHealth, the large majority (75 %) were willing to start. Most patients wanted to use mHealth in order to receive more information on physical health, and advice on progression of symptoms or signs of deterioration. Analyses on age, gender and complexity of defect showed significantly less current smartphone usage at older age, but no difference in interest or preferences in type of mHealth application for the near future.

Conclusion

The relatively young adult CHD population only rarely uses mHealth, but the majority are motivated to start using mHealth. New mHealth initiatives are required in these patients with a chronic condition who need lifelong surveillance in order to reveal if a reduction in morbidity and mortality and improvement in quality of life can be achieved.

Cardiac and Respiratory Disease in Aged Horses

Respiratory and cardiac diseases are common in older horses. Advancing age is a specific risk factor for cardiac murmurs and these are more likely in males and small horses. Airway inflammation is the most common respiratory diagnosis. Recurrent airway obstruction can lead to irreversible structural change and bronchiectasis; with chronic hypoxia, right heart dysfunction and failure can develop. Valvular heart disease most often affects the aortic and/or the mitral valve. Management of comorbidity is an essential element of the therapeutic approach to cardiac and respiratory disease in older equids.

Management of supraventricular arrhythmias in adults with congenital heart disease

Supraventricular arrhythmias are a frequent complication in adults with congenital heart disease (ACHD). The prevalence increases with time since surgery, complexity of the underlying defect, type of repair and older age at surgery. Arrhythmias are the most frequent reason for hospital admission and along with heart failure the leading cause of death. The arrhythmia-associated increase in morbidity and mortality makes their management a key task in patients with ACHD. Intra-atrial re-entry is the most frequent arrhythmia mechanism. Less common arrhythmia mechanisms are supraventricular tachycardias in the presence of an accessory pathway, atrioventricular nodal re-entrant tachycardia or focal tachycardias. Patient management includes stroke prevention, acute termination and prevention of arrhythmia recurrence. Acute treatment depends on patients' symptoms. In cases of haemodynamic instability, immediate cardioversion is warranted. For stable patients, acute treatment includes rate control and termination by antiarrhythmic drugs or electrical cardioversion. Following a symptomatic arrhythmia, catheter ablation or treatment with antiarrhythmic drugs is recommended to prevent recurrences. Advances in mapping and ablation technology are now associated with high success rates of catheter ablation. In patients with a complex substrate recurrence rates of 50% remain high. However, in the presence of side effects and complications associated with long-term antiarrhythmic drug therapy, redo procedures are encouraged by current guidelines.

Sotalol

Sotalol is effective for treating atrial fibrillation (AF), ventricular tachycardia, premature ventricular contractions, and supraventricular tachycardia. Racemic (DL) sotalol inhibits the rapid component of the delayed rectifier potassium current. There is a near linear relationship between sotalol dosage and QT interval prolongation. However, in dose ranging trials in patients with AF, low-dose sotalol was not more effective than placebo. Orally administered sotalol has a bioavailability of nearly 100%. The only significant drug interactions are the need to avoid or limit use of concomitant drugs that cause QT prolongation, bradycardia, and/or hypotension.

[Arrhythmia in adults with congenital heart disease : Acute and long-term management]

During the last few decades, the management of cardiac arrhythmias in adult patients with congenital heart disease (CHD) has undergone a significant change from a conservative, mainly pharmacological approach, to interventional techniques such as catheter ablation or device implantation (pacemakers, implantable cardioverter defibrillators [ICD]). The long-term efficacy of these strategies is as dependent on the hemodynamic status of the patient and the type of arrhythmia as it is on the underlying heart defect and any preceding surgery. Pharmacological agents and electrical cardioversion are at the forefront of treatment for tachyarrhythmias. Individualized thromboprophylaxis plays an important role in acute and in long-term management. Catheter ablation seems to show a more favorable outcome compared with a pharmacological approach in the long-term management of supraventricular tachyarrhythmias. Surgical procedures, including arrhythmia surgery (such as the Fontan conversion operation), may improve the arrhythmia. In symptomatic patients with bradyarrhythmias, such as sinus node dysfunction, pacemaker implantation is usually indicated. In the management of ventricular arrhythmias catheter ablation is also increasingly used. This is dominated by the individual risk stratification for the prevention of sudden cardiac death (SCD). However, the ICD is still the therapeutic cornerstone in most cases. The management of cardiac arrhythmias in adult CHD patients should be performed at specialized centers where all aspects of diagnosis and treatment are covered.