Sudden Cardiac Death in Adult Congenital Heart Disease

Autopsy results and factors associated with sudden cardiac death in young individuals with congenital heart disease - a nationwide study

OBJECTIVES

Sudden cardiac death (SCD) is a leading cause of mortality among individuals with congenital heart disease (CHD), and risk stratification remains challenging. This study aimed to describe the underlying structural cardiac abnormalities in a national cohort of SCD victims with CHD, their socioeconomic status, and interactions with the healthcare system before death.

METHODS

The Swedish study of Sudden Cardiac Death in the Young, 2000-2010, included SCD victims under 36 years, along with population-based controls and their parents. Of 903 SCD victims, 39 with autopsy-defined CHD were included in this study, together with 195 controls. Information on socioeconomic variables and healthcare contacts was gathered from Swedish national registers.

RESULTS

The median age for SCD was 24 years, and 64% were male. The CHD was undiagnosed before death in 31% of the cases, of whom 8 had coronary anomalies. Moderate to complex CHD was observed in 41%. Structural abnormalities of the ventricles were prevalent, with left ventricular hypertrophy present in 56% and fibrosis in 64%. The cases had a higher frequency of hospital admissions within 6 months before SCD compared to controls (OR 14.1,95% CI 3.80-52.44), p < 0.001. No socioeconomic differences were observed.

CONCLUSIONS

This study identified a broad spectrum of underlying anatomical defects, with ventricular structural abnormalities being a common autopsy finding. The majority of cases had moderate to severe lesions. An increased frequency of healthcare contacts prior to death was noted, which may be a variable needing more attention as a predictor for a higher risk of SCD.

Risk of late sudden death after surgery for congenital heart disease

BACKGROUND

Sudden cardiac death is a significant concern among patients with congenital heart disease (CHD). We assessed the risk of remote sudden cardiac death after congenital heart surgery.

METHODS

Patients undergoing congenital heart surgery before 21 years of age between 1982 and 2003 in the Pediatric Cardiac Care Consortium registry were linked to National Death Index data through 2019. Sudden cardiac death was defined as death associated with a cardiac arrest or ventricular fibrillation diagnosis code. Standardised mortality ratios relative to the general population were calculated using Centers for Disease Control and Prevention data.

RESULTS

Among 30,566 patients discharged after their initial surgery, 2,718 deaths occurred over a median period of 23 years (IQR 19-27). Of 463 (17%) sudden cardiac deaths, the median age was 1.7 years (IQR 0.5-16.5). The mean incidence was 7 per 10,000 person-years (95% CI: 0.64-0.77), ranging from 2.7 for left-to-right shunt lesions to 37 for single-ventricle physiology. Cardiac comorbidities including heart failure (13.6%) and arrhythmias (7.1%) were more frequent among sudden cardiac death patients. Standard mortality ratios for sudden cardiac death were elevated across all CHD types, ranging from 8.0 (95% CI: 6.3-9.6) for left-to-right shunts to 107.7 (95% CI: 88.9-126.5) for single-ventricle physiology.

CONCLUSION

Sudden cardiac death risk is higher post-congenital heart surgery compared to the general population. Even patients with mild CHD are at risk, highlighting the need for long-term follow-up for all patients. Heart failure and arrhythmia prevalence suggest potential therapeutic targets to reduce sudden cardiac death risk.

Long term outcome after surgical tetralogy of Fallot repair at young age: Longitudinal follow-up up to 50 years after surgery

BACKGROUND

Little is known about the very long-term outcome in Tetralogy of Fallot (ToF) patients.

OBJECTIVES

To prospectively evaluate clinical outcome and quality-of-life after surgical repair of ToF.

METHODS

Single-centre, longitudinal cohort-study evaluating every decade 144 ToF patients who underwent surgical repair <15 years of age between 1968 and 1980.

RESULTS

Evaluated were 66 patients (92 %) of the 72 eligible survivors (58 % male, median age at study 48.5 years) with a median follow-up of 45 (range 39-52) years. Cumulative survival at 50 years was 71 % and 84 % when excluding 30-days mortality, while event-free survival was 9 %. Reintervention (40 %) and symptomatic arrhythmias (21 %) were the most common complications, although ventricular tachycardia (VT) was rare (7 %). Cardiac magnetic resonance imaging showed a right ventricular ejection fraction <45 % in 45 % of the cohort and 42 % had a diminished left ventricular function. The aortic root diameter increased over time to >40 mm in 45 % of patients. VO2max was reduced in 53 % of patients but stable over time. Self-perceived quality-of-life was stable and comparable to the general Dutch population. Early post-operative arrhythmias, pre-operative low oxygen saturation of the left atrium, VT and declining exercise capacity over time were predictive for mortality, transannular patch for both arrhythmia and pulmonary valve replacement. Surgery post-1975 was protective for pulmonary valve replacement.

CONCLUSION

Only 9 % of ToF patients is alive without a major event at 50 years after surgical repair. Reintervention and symptomatic arrhythmias are especially common, although symptomatic VT is rare. Exercise capacity and self-perceived quality-of-life remained stable.

From Surviving to Thriving: A Roadmap for Reinventing Cardiac Rehabilitation in Pediatric Congenital Heart Disease

Exercise is an essential component of the cardiac care of children with congenital heart disease (CHD), and safe and effective exercise counselling by the medical team is important early in life to develop positive physical activity and exercise habits. Without it, children are at risk for sedentariness and related comorbidities in childhood and adulthood. Pediatric cardiologists can guide patients to a cycle of positive fitness through exercise counselling, promotion, prescription, and/or supervised exercise training similar to adult cardiac rehabilitation (ACR). ACR has improved exercise capacity, mortality, and quality of life in adults with acquired heart disease. Similar outcomes have been shown in exercise training for adult and pediatric CHD. Exercise training specific to pediatric CHD is not widely available but is expanding in response to growing need and increasing demand. Although ACR provides a framework for structured exercise training, approaches to pediatric exercise training must be individualized and innovated upon to be successful for children. I propose that the ACR model must be reinvented for children with CHD by integrating 6 missing pieces. First, the underlying goal should be to optimize fitness, not rehabilitate to a previous state of health. Second and third are training mental skills and motor skills. Fourth, play-based exercise training is needed to foster a positive relationship with exercise. Fifth, family-focused exercise interventions can address root causes of sedentariness. Finally, building communities in which positive fitness is a priority will be essential to long-term sustainability.

Toronto ACHD program: A 65 year legacy

The Toronto Adult Congenital Heart Disease (ACHD) Program at the University Health Network, University of Toronto, began in 1959. It traces its origins to a Paul Wood protégé, Dr. John Evans, and to a long-standing and supportive relationship with Hospital for Sick Children (SickKids), located just across the street. Over the decades, the program has grown to become a major center for training and research in ACHD and one of the largest clinical programs for ACHD care globally. This paper recounts the 65-year history of the program, including some of its key individuals, challenges, milestones, innovations, discoveries, and future aspirations.

Role of subpulmonary right ventricle in sudden cardiac death in adults with congenital heart disease

Despite improved childhood survival of congenital heart disease (CHD) as a result of advances in management, late-onset sudden cardiac death (SCD) from malignant ventricular arrhythmias remains a leading cause of mortality in adults with CHD. Preventing SCD in these patients requires an understanding of the underlying pathophysiological mechanisms. Many CHD patients experience significant hemodynamic stress on the subpulmonary right ventricle (RV), leading to pathologic remodeling. Unlike acquired heart disease in which left ventricular pathology is prevalent, RV pathologies are crucial in the SCD pathogenesis in CHD patients. This review examines the mechanisms and management of SCD related to subpulmonary RV pathologies in CHD patients.

Electrocardiographic correlates of ventricular arrhythmias in repaired congenital heart disease

Background

Sudden cardiac death (SCD) is a major cause of mortality in congenital heart disease (CHD). Ventricular arrhythmias (VAs) are responsible for 80% of SCD. However, the clinical characteristics of patients with CHD and VAs are not fully understood.

Objective

This study was undertaken to evaluate clinical and electrocardiographic characteristics of patients with CHD based on the presence or absence of VAs.

Methods

We identified 28 patients with CHD with VAs (men, n = 15; 35.9 ± 16.5 years). Two patients with channelopathies were excluded from the analysis.

Results

The most common diagnoses in patients with VAs were a transposition of the great arteries (n = 8, 30.8%), followed by tetralogy of Fallot (n = 7, 26.9%). Compared with patients without VA (n = 43), those with VAs had a longer QRS (160.6 ± 52.9 ms vs 133.4 ± 29.3 ms; P = .004), a higher prevalence of fragmented QRS (65.4% vs 37.2%; P = .022) and more epsilon wave (23.1% vs 2.3%; P = .005). Multivariable analysis showed that QRS > 180 ms (odds ratio [OR], 22.23; 95% confidence interval [CI], 2.40-206.53) and epsilon wave (OR, 14.33; 95% CI, 1.47-139.58) were significantly associated with VAs. During a median follow-up duration of 5.4 years, 5 patients (19.2%) received appropriate ICD therapy, and 3 patients (11.5%) died of heart failure.

Conclusion

The assessment of QRS duration and the presence of fQRS and epsilon waves in patients with CHD could improve risk prediction for the development of VAs. These electrocardiogram (ECG) features could assist in clinical decision-making and might consequently reduce mortality.

Cardiac MRI Predictors of Arrhythmic Sudden Cardiac Events in Patients With Fontan Circulation

BACKGROUND

Among patients with congenital heart disease, those with single ventricles have the highest risk of early mortality. Sudden cardiac death is an important cause of death in this population. Understanding the risk factors for sudden cardiac events (SCE) in Fontan patients could improve prediction and prevention.

OBJECTIVES

The goal of this study was to determine the prevalence of SCE and risk factors for SCE in the Fontan population.

METHODS

The Fontan Outcomes Registry Using CMR Examinations (FORCE) is an international registry collecting clinical and imaging data on Fontan patients. SCE was defined as: 1) cardiac arrest from a shockable rhythm; 2) need for emergent cardioversion/defibrillation; or 3) documented sustained ventricular tachycardia. Univariate and multivariate Cox proportional hazards regression models estimated hazard ratios for predictors of SCE.

RESULTS

Our sample included 3,132 patients (41% female). The median age at first cardiac magnetic resonance was 14.6 years. SCE was experienced by 3.5% (n = 109) over a median follow-up time of 4.00 years. Of the 109 patients with SCE, 39 (36%) died. On multivariable analysis, NYHA functional class >II (HR: 4.91; P < 0.0001), history of protein-losing enteropathy/plastic bronchitis (HR: 2.37; P = 0.0082), single-ventricle end-diastolic volume index >104 mL/m2 (HR: 3.15; P < 0.0001), and ejection fraction <50% (HR: 1.73; P = 0.0437) were associated with SCE. Kaplan-Meier analysis demonstrated that in patients with none of the above risk factors, the 4-year freedom from SCE was 99.5%.

CONCLUSIONS

SCE occurred in 3.5% of the study population, and one-third of patients who experienced SCE died. Mild ventricular dysfunction and dilatation by cardiac magnetic resonance, NYHA functional class, and history of protein-losing enteropathy/plastic bronchitis were associated with SCE.

Long-Term Management of Right Ventricular Outflow Tract Dysfunction in Repaired Tetralogy of Fallot: A Scientific Statement From the American Heart Association

Right ventricular outflow dysfunction, manifesting as stenosis, regurgitation, or both, is nearly universal in patients with repaired tetralogy of Fallot, precipitating a complex pathophysiological cascade that leads to increasing rates of morbidity and mortality with advancing age. As the number of adolescent and adult patients with repaired tetralogy of Fallot continues to grow as a result of excellent survival during infancy, the need to improve late outcomes has become an urgent priority. This American Heart Association scientific statement provides an update on the current state of knowledge of the pathophysiology, methods of surveillance, risk stratification, and latest available therapies, including transcatheter and surgical pulmonary valve replacement strategies, as well as management of life-threatening arrhythmias. It reviews emerging evidence on the roles of comorbidities and patient-reported outcomes and their impact on quality of life. In addition, this scientific statement explores contemporary evidence for clinical choices such as transcatheter or surgical pulmonary valve replacement, discusses criteria and options for intervention for failing implanted bioprosthetic pulmonary valves, and considers a new approach to determining optimal timing and indications for pulmonary valve replacement.

Risk factors and early outcomes of repeat sternotomy in 1960 adults with congenital heart disease: A 30-year, single-center study

OBJECTIVE

Patients with congenital heart disease (CHD) increasingly live into adulthood, often requiring cardiac reoperation. We aimed to assess the outcomes of adults with CHD (ACHD) undergoing repeat sternotomy at our institution.

METHODS

Review of our institution's cardiac surgery database identified 1960 ACHD patients undergoing repeat median sternotomy from 1993 to 2023. The primary outcome was early mortality, and the secondary outcome was a composite end point of mortality and significant morbidity. Univariable and multivariable logistic regression models were used to determine factors independently associated with outcomes.

RESULTS

Of the 1960 ACHDs patient undergoing repeat sternotomy, 1183 (60.3%) underwent a second, third (n = 506, 25.8%), fourth (n = 168, 8.5%), fifth (n = 70, 3.5%), and sixth sternotomy or greater (n = 33, 1.6%). CHD diagnoses were minor complexity (n = 145, 7.4%), moderate complexity (n = 1380, 70.4%), and major complexity (n = 435, 22.1%). Distribution of procedures included valve (n = 549, 28%), congenital (n = 625, 32%), aortic (n = 104, 5.3%), and major procedural combinations (n = 682, 34.7%). Overall early mortality was 3.1%. Factors independently associated with early mortality were older age at surgery, CHD of major complexity, preoperative renal failure, preoperative ejection fraction, urgent operation, and postoperative blood transfusion. In addition, sternotomy number and bypass time were independently associated with the composite outcome.

CONCLUSIONS

Despite the increase in early mortality with sternotomy number, sternotomy number was not independently associated with early mortality but with increased morbidity. Improvement strategies should target factors leading to urgent operations, early referral, along with operative efficiency including bypass time and blood conservation.

Intracardiac Echocardiography to Assist Anatomical Isthmus Ablation in Repaired Tetralogy of Fallot Patients With Ventricular Tachycardia: Technique and Outcomes

Background

Successful catheter ablation of ventricular tachycardia (VT) in repaired tetralogy of Fallot (TOF) can be achieved by targeting 1 or more anatomical isthmuses. However, significant interindividual variability in the size and location of surgical patches means careful mapping is required to design ablation lines to block the isthmus. Intracardiac echocardiography (ICE) may assist ablation by accurate identification of individual TOF anatomy.

Objectives

The authors hypothesized ICE-guided VT ablation improved isthmus recognition, ablation, and procedural outcomes.

Methods

Retrospective study of adults with repaired TOF undergoing VT ablation between January 1, 2017 and December 31, 2022. ICE integration was compared to a strategy using electroanatomical mapping only to identify anatomic boundaries. All cases underwent ablation and had proven isthmus block as the procedural endpoint.

Results

Twenty-three patients (age 47 ± 14 years; 61% male) underwent 27 VT ablations (ICE: 16/27 [59%]; no ICE: 11/27 [41%]). ICE improved the ability to localize and ablate the anatomical isthmus (ICE: 13/15 [87%] vs no ICE: 4/11 [36%]; P = 0.014); however, there was no difference in long-term freedom from VT (ICE: 9/12 [75%] vs no ICE: 8/11 [73%]; P = 0.901). ICE had no impact on procedural times (ICE: 173 ± 48 minutes vs no ICE: 157 ± 47 minutes; P = 0.399), fluoroscopy time (ICE: 30 ± 16 minutes vs no ICE: 29 ± 10 minutes; P = 0.864), or major complications (ICE: 1/16 [6%] vs no ICE 0/11; P = 1.000).

Conclusions

ICE improves ablation of the anatomical isthmus for sustaining VT in patients with repaired TOF by demonstrating the individual anatomy but does not improve long-term outcomes.

Adults with congenital heart disease: what every cardiologist should know about their care

As patients with congenital heart disease (CHD) continue to enjoy longer lives, non-congenital cardiologists and other healthcare professionals are increasingly encountering them in their practice and are challenged by their specific needs. Most under- and post-graduate medical training tends to overlook this common pathology, resulting in insufficient awareness of post-repair or post-palliation residual lesions and sequelae from previous interventions. In a strive towards improving the quality of care for this ever-growing cardiovascular patient cohort, it is prudent to outline the areas of concern and specific management needs pertaining to adult patients with CHD and share it with non-CHD professionals. The purpose of this paper is to offer essential guidance to physicians, including cardiologists, when they encounter a patient with CHD in a non-congenital healthcare setting.

Long-term outcomes of ventricular tachycardia ablation in repaired tetralogy of Fallot: Systematic review and meta-analysis

Background

Ventricular tachycardia (VT) remains a risk in repaired Tetralogy of Fallot (rTOF); however, long-term benefits of VT ablation have not been established. This study compares the outcomes of rTOF patients with and without VT ablation.

Methods

We searched multiple databases examining the outcomes of rTOF patients who had undergone VT ablation compared to those without ablation. Primary outcomes were VT recurrence, sudden cardiac death (SCD), and all-cause mortality. Subgroup analysis was conducted based on the type of ablation (catheter and surgical). Slow-conducting anatomical isthmus (SCAI)-based catheter ablation (CA) was also analyzed separately. The secondary outcome was the risk factors for the pre-ablation history of VT.

Results

Fifteen cohort studies with 1459 patients were included, 21.4% exhibited VTs. SCAI was found in 30.4% of the population, with 3.7% of non-inducible VT. Factors significantly associated with VT before ablation included a history of ventriculostomy, QRS duration ≥180 ms, fragmented QRS, moderate to severe pulmonary regurgitation, high premature ventricular contractions burden, late gadolinium enhancement, and SCAI. Ablation was only beneficial in reducing VTs recurrence in SCAI-based CA (risk ratio (RR) 0.11; 95% CI 0.03 to 0.33. p < 0.001; I2 = 0%) with no recurrence in patients with preventive ablation (mean follow-up time 91.14 ± 77.81 months). The outcomes of VT ablation indicated a favorable trend concerning SCD and all-cause mortality (RR 0.49 and 0.44, respectively); however, they were statistically insignificant.

Conclusions

SCAI-based CA has significant advantages in reducing VT recurrence in rTOF patients. Risk stratification plays a key role in determining the decision to perform ablation.

Using artificial intelligence and deep learning to optimise the selection of adult congenital heart disease patients in S-ICD screening

INTRODUCTION

The risk of complications associated with transvenous ICDs make the subcutaneous implantable cardiac defibrillator (S-ICD) a valuable alternative in patients with adult congenital heart disease (ACHD). However, higher S-ICD ineligibility and higher inappropriate shock rates-mostly caused by T wave oversensing (TWO)- are observed in this population. We report a novel application of deep learning methods to screen patients for S-ICD eligibility over a longer period than conventional screening.

METHODS

Adult patients with ACHD and a control group of normal subjects were fitted with a 24-h Holters to record their S-ICD vectors. Their T:R ratio was analysed utilising phase space reconstruction matrices and a deep learning-based model to provide an in-depth description of the T: R variation plot for each vector. T: R variation was compared statistically using t-test.

RESULTS

13 patients (age 37.4 ± 7.89 years, 61.5 % male, 6 ACHD and 7 control subjects) were enrolled. A significant difference was observed in the mean and median T: R values between the two groups (p < 0.001). There was also a significant difference in the standard deviation of T: R between both groups (p = 0.04).

CONCLUSIONS

T:R ratio, a main determinant for S-ICD eligibility, is significantly higher with more tendency to fluctuate in ACHD patients when compared to a population with normal hearts. We hypothesise that our novel model could be used to select S-ICD eligible patients by better characterisation of T:R ratio, reducing the risk of TWO and inappropriate shocks in the ACHD patient cohort.

Tachyarrhythmias in congenital heart disease

The prevalence of congenital heart disease (CHD) in adult patients has risen with advances in diagnostic and surgical techniques. Surgical modifications and hemodynamic changes increase the susceptibility to arrhythmias, impacting morbidity and mortality rates, with arrhythmias being the leading cause of hospitalizations and sudden deaths. Patients with CHD commonly experience both supraventricular and ventricular arrhythmias, with each CHD type associated with different arrhythmia patterns. Macroreentrant atrial tachycardias, particularly cavotricuspid isthmus-dependent flutter, are frequently reported. Ventricular arrhythmias, including monomorphic ventricular tachycardia, are prevalent, especially in patients with surgical scars. Pharmacological therapy involves antiarrhythmic and anticoagulant drugs, though data are limited with potential adverse effects. Catheter ablation is preferred, demanding meticulous procedural planning due to anatomical complexity and vascular access challenges. Combining imaging techniques with electroanatomic navigation enhances outcomes. However, risk stratification for sudden death remains challenging due to anatomical variability. This article practically reviews the most common tachyarrhythmias, treatment options, and clinical management strategies for these patients.

Clinical Factors Affecting Survival in Patients with Congenitally Corrected Transposition of the Great Arteries: A Systematic Review and Meta-Analysis

Background: Congenitally corrected transposition of the great arteries (cc-TGA) is a defect characterized by arterio-ventricular and atrioventricular disconcordance. Most patients have co-existing cardiac abnormalities that warrant further treatment. Some patients do not require surgical intervention, but most undergo physiological repair or anatomical surgery, which enables them to reach adulthood. Aims: We aimed to evaluate mortality risk factors in patients with cc-TGA. Results: We searched the PubMed database and included 10 retrospective cohort studies with at least a 5-year follow-up time with an end-point of cardiovascular death a minimum of 30 days after surgery. We enrolled 532 patients, and 83 met the end-point of cardiovascular death or equivalent event. As a risk factor for long-term mortality, we identified New York Heart Association (NYHA) class ≥III/heart failure hospitalization (OR = 10.53; 95% CI, 3.17-34.98) and systemic ventricle dysfunction (SVD; OR = 4.95; 95% CI, 2.55-9.64). We did not show history of supraventricular arrhythmia (OR = 2.78; 95% CI, 0.94-8.24), systemic valve regurgitation ≥moderate (SVR; OR = 4.02; 95% Cl, 0.84-19.18), and pacemaker implantation (OR = 1.48; 95% Cl, 0.12-18.82) to affect the long-term survival. In operated patients only, SVD (OR = 4.69; 95% CI, 2.06-10.71) and SVR (OR = 3.85; 95% CI, 1.5-9.85) showed a statistically significant impact on survival. Conclusions: The risk factors for long-term mortality for the entire cc-TGA population are NYHA class ≥III/heart failure hospitalization and systemic ventricle dysfunction. In operated patients, systemic ventricle dysfunction and at least moderate systemic valve regurgitation were found to affect survival.

In-Hospital Death and End-of-Life Status Among Patients With Adult Congenital Heart Disease - A Retrospective Study Using the JROAD-DPC Database in Japan

BACKGROUND

The end-of-life (EOL) status, including age at death and treatment details, of patients with adult congenital heart disease (ACHD) remains unclear. This study investigated the EOL status of patients with ACHD using a nationwide Japanese database.

METHODS AND RESULTS

Data on the last hospitalization of 26,438 patients with ACHD aged ≥15 years, admitted between 2013 and 2017, were included. Disease complexity (simple, moderate, or great) was classified using International Classification of Diseases, 10th Revision codes. Of the 853 deaths, 831 patients with classifiable disease complexity were evaluated for EOL status. The median age at death of patients in the simple, moderate, and great disease complexity groups was 77.0, 66.5, and 39.0 years , respectively. The treatments administered before death to patients in the simple, moderate, and great complexity groups included cardiopulmonary resuscitation (30.1%, 35.7%, and 41.9%, respectively), percutaneous cardiopulmonary support (7.2%, 16.5%, and 16.3%, respectively), and mechanical ventilation (58.7%, 72.2%, and 75.6%, respectively). Overall, 70% of patients died outside of specialized facilities, with >25% dying after ≥31 days of hospitalization.

CONCLUSIONS

Nationwide data showed that patients with ACHD with greater disease complexity died at a younger age and underwent more invasive treatments before death, with many dying after ≥1 month of hospitalization. Discussing EOL options with patients at the appropriate time is important, particularly for patients with greater disease complexity.

Value of Extended Arrhythmia Screening in Adult Congenital Heart Disease Patients

The European Society of Cardiology guidelines for the management of adult congenital heart disease patients recommend screening for arrhythmias and bradycardias in symptomatic patients, often being done by means of an ambulatory 24-48-hour Holter or implantable loop recorder (ILR). However, nowadays non-invasive instruments, such as patches, smartwatches and smartphones based on single-lead ECGs that perform extended monitoring, are also available. The aim of this narrative review was to assess whether these instruments, when they detect arrhythmias and bradycardias in patients with adult congenital heart disease, will lead to meaningful changes in clinical care. Clinically meaningful changes include adjustment of medication, cardioversion, electrophysiology study, ablation or implantation of a cardiovascular implantable electronic device. The following monitoring instruments are discussed: cumulative Holter, 2-week continuous monitor, smartwatchand smartphone-based single-lead ECG, and ILR. The diagnostic yield of extended rhythm monitoring is high, and varies between 18% (smartphone-based single-lead ECG) and 41% with ILR. In conclusion, contemporary arrhythmia screening includes various new non-invasive technologies that are promising new tools as an alternative to Holter monitoring or ILR. However, the optimal mode of detection is still unclear due to the lack of head-to-head comparisons.

Parental recommendations and exercise attitudes in congenital hearts

BACKGROUND

Children and young people with CHD benefit from regular physical activity. Parents are reported as facilitators and barriers to their children's physical activity. The aim of this study was to explore parental factors, child factors, and their clinical experience on physical activity participation in young people with CHD.

METHODS

An online questionnaire was co-developed with parents (n = 3) who have children with CHD. The survey was then distributed in the United Kingdom by social media and CHD networks, between October 2021 and February 2022. Data were analysed using mixed methods.

RESULTS

Eighty-three parents/guardians responded (94% mothers). Young people with CHD were 7.3 ± 5.0 years old (range 0-20 years; 53% female) and 84% performed activity. Parental participation in activity (X2(1) = 6.9, P < 0.05) and perceiving activity as important for their child were positively associated with activity (Fisher's Exact, P < 0.05). Some parents (∼15%) were unsure of the safety of activity, and most (∼70%) were unsure where to access further information about activity. Fifty-two parents (72%) had never received activity advice in clinic, and of the 20 who received advice, 10 said it was inconsistent. Qualitative analysis produced the theme "Knowledge is power and comfort." Parents described not knowing what activity was appropriate or the impact of it on their child.

CONCLUSION

Parental participation and attitudes towards activity potentially influence their child's activity. A large proportion of young people performed activity despite a lack and inconsistency of activity advice offered by CHD clinics. Young people with CHD would benefit from activity advice with their families in clinics.

Arrhythmic Risk and Treatment after Transcatheter Atrial Septal Defect Closure

Atrial septal defect (ASD) represents the most common congenital heart defect identified in adulthood. Atrial and ventricular geometric remodeling due to intracardiac shunt increase the risk of arrhythmias, especially atrial fibrillation (AF). Clinical, echocardiography, electrocardiogram, and device-related predictors may be used to assess the risk of atrial arrhythmias after ASD closure. The underlying mechanisms in these patients are complex and at least in part independent of the structural remodeling secondary to hemodynamic overload. Device closure of the ASD itself and its timing impact future arrhythmia risk, as well as posing a challenge for when transseptal puncture is required. Sudden cardiac death (SCD) risk is higher than in the general population and an implantable cardioverter-defibrillator (ICD) may be indicated in selected cases.

Exercise as Medicine: Evaluation and Prescription for Adults with Congenital Heart Disease

PURPOSE OF REVIEW

Understanding exercise physiology as it relates to adult congenital heart disease (ACHD) can be complex. Here we review fundamental physiologic principles and provide a framework for application to the unique ACHD patient population.

RECENT FINDINGS

ACHD exercise participation has changed dramatically in the last 50 years. A modern approach focuses on exercise principles and individual anatomic and physiologic considerations. With an evolving better understanding of ACHD exercise physiology, we can strategize plans for patients to participate in dynamic and static exercises. Newly developed technologies including wearable devices provide additive information for ACHD providers for further assessment and monitoring. Preparation and assessment for ACHD patients prior to exercise require a thoughtful, personalized approach. Exercise prescriptions can be formulated to adequately meet the needs of our patients.

Prediction of Sudden Death Risk in Patients with Congenital Heart Diseases

Risk stratification for sudden death should be discussed with patients with congenital heart disease at each stage of personal and cardiac development. For most patients, risk is low through teenage years and the critical factors to consider are anatomy, ventricular function, and symptoms. By adulthood, these are supplemented by screening for atrial arrhythmias, ventricular arrhythmias, and pulmonary hypertension. Therapies include medication, ablation, and defibrillator placement.

Mid-Term Electrical Remodeling after Percutaneous Atrial Septal Defect Closure with GCO Device in a Pediatric Population

BACKGROUND AND AIM

The GORE® CARDIOFORM (GCO) septal occluder is an atrial septal defect/patent foramen ovale closure device with theoretical advantages over other commercialized devices thanks to its softness and anatomical compliance. Our aim was to evaluate the short- and medium-term electrocardiographic changes after percutaneous ASD closure with GCO in a pediatric population.

METHODS

We enrolled 39 patients with isolated ASD submitted to trans-catheter closure from January 2020 to June 2021. ECG was performed before, at 24 h and 6 months after the procedure. P wave dispersion, QTc and QTc dispersion were calculated. ECG Holter was recorded at 6 months after implantation.

RESULTS

Patients' age and body surface area (BSA) were 8.2 ± 4.2 years and 1.0 ± 0.3 m2 respectively. At the baseline, mean P wave dispersion was 40 ± 15 msec and decreased at 24 h (p < 0.002), without any further change at 6 months. At 24 h, PR conduction and QTc dispersion significantly improved (p = 0.018 and p < 0.02 respectively), while the absolute QTc value considerably improved after 6 months. During mid-term follow-up, QTc dispersion remained stable without a significant change in PR conduction. The baseline cardiac frequency was 88.6 ± 12.6 bpm, followed by a slight reduction at 24 h, with a further amelioration at 6 months after the procedure (87.3 ± 14.2, p = 0.9 and 81.0 ± 12.7, p = 0.009, respectively). After device deployment, two patients developed transient, self-limited junctional rhythm. One of them needed a short course of Flecainide for atrial ectopic tachycardia. No tachy/brady-arrhythmias were recorded at the 6-month follow-up. ASD closure resulted in a marked decrease in right heart volumes and diameters at 6 months after percutaneous closure.

CONCLUSIONS

Percutaneous ASD closure with the GCO device results in significant, sudden improvement of intra-atrial, atrio-ventricular and intraventricular electrical homogeneity. This benefit persists unaltered over a medium-term follow-up. These electrical changes are associated with a documented positive right heart volumetric remodeling at mid-term follow-up.

Exercise, prescription and training in ACHD

The number of adult patients with congenital heart disease (CHD) is steadily increasing and exceeds nowadays the number of children with CHD. This is due to significant advances in therapeutic possibilities that became available over the last four decades. As such, this aging population survives the CHD complications and is exposed to the traditional cardiovascular risk factors for atherosclerotic disease such as high blood pressure, elevated cholesterol levels, long-standing exposure to smoking, overweight and obesity, and a sedentary lifestyle. Consequently, it becomes important to put more emphasis on all these risk factors. A preventive strategy is central, and early encouragement of physical activity is part of this approach. A minimum of physical activity has a beneficial effect both physically and mentally. With this overview, we mainly want to emphasize the importance of preventive measures. We would like to emphasize that all individuals should receive an exercise prescription which adheres to the minimum recommendations by WHO/NICE and this advice should form the baseline. Moreover, we intend to show that physical activity can be done safely in patients with CHD and that recreational and competitive sports are feasible in many circumstances.

A comparison of ECG-based home monitoring devices in adults with CHD

BACKGROUND

Various electrocardiogram (ECG)-based devices are available for home monitoring, but the reliability in adults with CHD is unknown. Therefore, we determined the accuracy of different ECG-based devices compared to the standard 12-lead ECG in adult CHD.

METHODS AND RESULTS

This is a single-centre, prospective, cross-sectional study in 176 consecutive adults with CHD (54% male, age 40 ± 16.6 years, 24% severe CHD, 84% previous surgery, 3% atrial fibrillation (AF), 24% right bundle branch block). Diagnostic accuracy of the Withings Scanwatch (lead I), Eko DUO (precordial lead), and Kardia 6L (six leads) was determined in comparison to the standard 12-lead ECG on several tasks: 1) AF classification (percentage correct), 2) QRS-morphology classification (percentage correct), and 3) ECG intervals calculation (QTc time ≤ 40 ms difference). Both tested AF algorithms had high accuracy (Withings: 100%, Kardia 6L: 97%) in ECGs that were classified. However, the Withings algorithm classified fewer ECGs as inconclusive (5%) compared to 31% of Kardia (p < 0.001). Physician evaluation of Kardia correctly classified QRS morphology more frequently (90% accuracy) compared to Eko DUO (84% accuracy) (p = 0.03). QTc was underestimated on all ECG-based devices (p < 0.01). QTc duration accuracy was acceptable in only 51% of Withings versus 70% Eko and 74% Kardia (p < 0.001 for both comparisons).

CONCLUSIONS

Although all devices demonstrated high accuracy in AF detection, the Withings automatic algorithm had fewest uninterpretable results. Kardia 6L was most accurate in overall evaluation such as QRS morphology and QTc duration. These findings can inform both patients and caregivers for optimal choice of home monitoring.

Optimal rate control in dogs with atrial fibrillation-ORCA study-Multicenter prospective observational study: Prognostic impact and predictors of rate control

BACKGROUND

The optimal heart rate (HR) in dogs with atrial fibrillation (AF) is unknown. Impact of HR on survival needs elucidation.

HYPOTHESIS/OBJECTIVES

Dogs with a 24 hours Holter-derived meanHR ≤125 beats per minute (bpm; rate controlled) survive longer than dogs with higher meanHR. We further aimed to determine which variables predict ability to achieving rate control.

ANIMALS

Sixty dogs with AF.

METHODS

Holter-derived meanHR, clinical, echocardiographic, and biomarker variables were analyzed prospectively. Survival was recorded from time of rate control, with all-cause mortality as primary endpoint. Cox proportional hazards analysis identified variables independently associated with survival; Kaplan-Meier survival analysis estimated the median survival time of dogs with meanHR ≤125 bpm vs >125 bpm. Logistic regression explored baseline variables associated with inability to achieve rate control.

RESULTS

Structural heart disease was present in 56/60 dogs, 50/60 had congestive heart failure, and 45/60 died. Median time to all-cause death was 160 days (range, 88-303 days), dogs with meanHR >125 bpm (n = 27) lived 33 days (95% confidence interval [CI], 15-141 days), dogs with meanHR ≤125 bpm (n = 33) lived 608 days (95% CI, 155-880 days; P < .0001). Congenital heart disease and N-terminal pro-B-type natriuretic peptide were independently associated with higher risk of death (P < .01 and <.0001, respectively) whereas meanHR ≤125 bpm decreased the risk of death (P < .001). Increased left atrial size, increased C-reactive protein concentration and lower blood pressure at admission were associated with failure to achieve rate control.

CONCLUSIONS AND CLINICAL IMPORTANCE

Rate control affects survival; an optimal target meanHR <125 bpm should be sought in dogs with AF. Baseline patient variables can help predict if rate control is achievable.

Incidence and Clinical Predictors of Early and Late Complications of Implantable Cardioverter-Defibrillators in Adults With Congenital Heart Disease

BACKGROUND

The implantable cardioverter-defibrillator (ICD) has been proven to improve survival in adults with congenital heart disease (ACHD), but it is associated with a high rate of complications. We aimed to quantify the incidence of early (≤ 3 months; ECs) and late (> 3 months; LCs) complications in ACHD patients implanted with an ICD and to identify their clinical predictors.

METHODS

We retrospectively reviewed 207 patients who had ICD follow-up at Toronto General Hospital from 1996 to 2019.

RESULTS

The most common diagnoses were tetralogy of Fallot (32.4%), dextro-transposition of the great arteries (17.9%), and congenital corrected transposition of the great arteries (13%). No intraprocedural complications were observed. Median follow-up was 3.4 years (IQR 0.1-23). 24 patients (12%) developed EC (4 hematomas, 20 lead dislodgements). A total of 56 LCs occurred (46% lead failure, 21% infection, 11% prophylactic lead extraction, 9% neurologic pain, 9% erosion, 4% other) with an incidence rate of LCs of 18% per 5 person-years. Anatomic complexity (odds ratio 2.9; P = 0.02) and cardiac resynchronization therapy defibrillator implant (odds ratio 2.5; P = 0.04) were associated with ECs. Survival rates free from LCs were 92%, 86%, and 65%, respectively, after 1, 5, and 10 years. Presence of legacy leads (hazard ratio 2.9; P = 0.006) and subpulmonary ejection fraction (5% increase, hazard ratio 1.35; P = 0.031) were associated with LCs.

CONCLUSIONS

ACHD patients at risk of sudden cardiac death continue to benefit from newer device technology. However, these patients, particularly those with greater anatomic and device complexity, remain at increased risk of developing complications over their lifetime. Given the life expectancy of this population, careful consideration needs to be given when a device for primary prevention is being contemplated.

Ventricular Arrhythmic Events After Transcatheter Pulmonary Valve Replacement in Adults with Repaired Tetralogy of Fallot

Arrhythmias are a major cause of morbidity and mortality in repaired Tetralogy of Fallot (rTOF). However, predicting those at risk for life-threatening ventricular arrhythmias (VA) remains difficult. Many centers approach risk assessment at the time of surgical pulmonary valve intervention. Increasing numbers of patients have undergone transcatheter pulmonary valve replacement (TPVR), yet there are no studies evaluating VA in rTOF undergoing TPVR and the approach to risk assessment for these patients. A single center retrospective study was performed. The institutional interventional database was queried to identify all adults ≥ 18 years of age with rTOF status who underwent TPVR from 2010 to 2019. A total of 81 patients with rTOF underwent TPVR from 2010 to 2019. Mean age at time of TPVR was 27 ± 13 years; follow up after TPVR was 6.4 ± 3.1 years. VA events occurred in 4 patients (5%). There was no significant difference in current era VA risk factors in rTOF patients between the VA event group and the non-VA event group. VA risk in this cohort of rTOF with TPVR was 5%, comparable to that reported in current era surgical cohort with similar follow up. Multi-center agreement on risk assessment protocol is needed for future studies.

Rapid ventricular tachycardia in patients with tetralogy of Fallot and implantable cardioverter-defibrillator: Insights from the DAI-T4F nationwide registry

BACKGROUND

In repaired tetralogy of Fallot (TOF), little is known about characteristics of patients with rapid ventricular tachycardia (VT). Also, whether patients with a first episode of nonrapid VT may subsequently develop rapid VT or ventricular fibrillation (VF) has not been addressed.

OBJECTIVES

The objectives of this study were to compare patients with rapid VT/VF with those with nonrapid VT and to assess the evolution of VT cycle lengths (VTCLs) overtime.

METHODS

Data were analyzed from a nationwide registry including all patients with TOF and implantable cardioverter-defibrillator (ICD) since 2000. Patients with ≥1 VT episode with VTCL ≤250 ms (240 beats/min) formed the rapid VT/VF group.

RESULTS

Of 144 patients (mean age 42.0 ± 12.7 years; 104 [72%] men), 61 (42%) had at least 1 VT/VF episode, including 28 patients with rapid VT/VF (46%), during a median follow-up of 6.3 years (interquartile range 2.2-10.3 years). Compared with patients in the nonrapid VT group, those in the rapid VT/VF group were significantly younger at ICD implantation (35.2 ± 12.6 years vs 41.5 ± 11.2 years; P = .04), had more frequently a history of cardiac arrest (8 [29%] vs 2 [6%]; P = .02), less frequently a history of atrial arrhythmia (11 [42%] vs 22 [69%]; P = .004), and higher right ventricular ejection fraction (43.3% ± 10.3% vs 36.6% ± 11.2%; P = .04). The median VTCL of VT/VF episodes was 325 ms (interquartile range 235-429 ms). None of the patients with a first documented nonrapid VT episode had rapid VT/VF during follow-up.

CONCLUSION

Patients with TOF and rapid VT/VF had distinct clinical characteristics. The relatively low variation of VTCL over time suggests a room for catheter ablation without a backup ICD in selected patients with well-tolerated VT.

An implantable loop recorder or smartphone based single-lead electrocardiogram to detect arrhythmia in adults with congenital heart disease?

Background

The European Society of Cardiology (ESC) guidelines for the management of adult congenital heart disease (ACHD) recommend screening in patients at risk for arrhythmic events. However, the optimal mode of detection is unknown.

Methods

Baseline and follow-up data of symptomatic ACHD patients who received an implantable loop recorder (ILR) or who participated in a smartphone based single-lead electrocardiogram study were collected. The primary endpoint was time to first detected arrhythmia.

Results

In total 116 ACHD patients (mean age 42 years, 44% male) were studied. The ILR group (n = 23) differed from the smartphone based single-lead electrocardiogram group (n = 93) in having a greater part of males and had more severe CHD and (near) syncope as qualifying diagnosis. In the smartphone based single-lead electrocardiogram group history of arrhythmia and palpitations were more frequent (all p < 0.05). Monitoring was performed for 40 and 79 patient-years for the ILR- and smartphone based single-lead electrocardiogram group, respectively. Arrhythmias occurred in 33 patients with an equal median time for both groups to first arrhythmia of 3 months (HR of 0.7, p = 0.81). Furthermore, atrial fibrillation occurred most often (n = 16) and common therapy changes included medication changes (n = 7) and implantation of pacemaker or Implantable Cardioverter Defibrillator (ICD) (N = 4). Symptoms or mode of detection were not a determinant of the first event.

Conclusion

Non-invasive smartphone based single-lead electrocardiogram monitoring could be an acceptable alternative for ILR implantation in detecting arrhythmia in symptomatic ACHD patients in respect to diagnostic yield, safety and management decisions, especially in those without syncope.

Successful transvenous implantable cardioverter-defibrillator implantation supported by preceding 3D electro-anatomical mapping for a ventricular fibrillation survivor with surgically repaired congenitally corrected transposition of the great arteries: a case report

Background

The atrial sites suitable for lead placement are limited after complex surgical atrial procedures, and lead placement can be challenging in patients with congenitally corrected transposition of the great arteries (ccTGA) after intracardiac repair.

Case summary

A 34-year-old man with ccTGA, who had undergone a double-switch operation with combined Senning and Jatene operations at the age of 14 was transferred to us. He experienced faintness and suffered cardiopulmonary arrest, and electrocardiography revealed ventricular fibrillation. After conversion to sinus rhythm by urgent external defibrillation, sinus bradycardia was revealed. Electrophysiological study was done using a three-dimensional (3D) mapping system (Ensite®) to evaluate the electrical condition of atria and to decide whether atrial lead can be transvenously placed. The electrical potential of the functional right atrium was good in the lateral or posterior wall, but the threshold was high. By contrast, the roof of the functional right atrium beyond cavoatrial junction was characterized by low voltage, but in a limited region of the roof of right atrium, the threshold was satisfactory and the electrical potential was normal. Thus, 3 weeks later, we implanted a transvenous implantable cardioverter-defibrillator (ICD). We used a 3D mapping system to place the atrial lead in the limited region of the roof of the right atrium mentioned above, the threshold was 0.7 V.

Discussion

Electrophysiological examination using a 3D mapping system before implantation of a dual-chamber ICD is useful because atrial sites suitable for lead placement are limited in patients.

Sudden cardiac death in adults with congenital heart disease: Lessons to Learn from the ATROPOS registry

Sudden cardiac death (SCD) is one of the most frequent causes of death in adult patients with congenital heart disease (ACHD). Despite the rare frequency of its occurrence, the incident appears often when unexpected, and many affected patients had not been identified priorly. Data on predictors for SCD are limited since the total number of ACHD is low. As the cohort is heterogeneous, it is difficult to define uniform risk factors that apply to all ACHD. Complexity of the congenital heart disease appears to play a role, but other factors may also be relevant and have not been sufficiently identified yet. In current guidelines, recommendations are primarily based on data of patients without congenital heart disease. With the ATROPOS registry, we are aiming to identify reliable risk factors for SCD. The registry enables physicians globally to include patients with congenital heart disease who died of or survived SCD. After acquisition, the data will be compared to an age and complexity of disease matched cohort to perform a case-control analysis. Subsequently, a further analysis will be performed using deep learning algorithms with artificial intelligence to amplify the gathered information and find reliable risk factors.

Atrial Flutters in Adults with Congenital Heart Disease

The macroreentrant atrial tachycardia is very frequent in the adults with congenital heart disease. The impact of the arrhythmias on this type of patients is related to several factors: the anatomy and physiopathology of the specific congenital heart disease (CHD), the sequelae of the corrective surgery or surgical palliation, the presence of residual lesions (shunt, regurgitation), and the age and the clinical status of the patient and the comorbidities. In turn, the mechanism of the MAT depends on the peculiar features of the conduction's system in the CHD and native and acquired (post-surgery) substrates.

Behind Enemy Lines: Vital Echocardiographic Data Prior to Ventricular Arrhythmia Ablation

Ventricular arrhythmias (VA) are a major cause of sudden cardiac death (SCD). Echocardiography is the first widely available imaging tool which guides VA management strategies. Along with other invasive and noninvasive imaging techniques, it provides essential information for identification of VA substrate such as differentiation between ischemic and non-ischemic etiology and identification of structural heart disease. Both classic as well as novel echocardiographic techniques such as left ventricular strain measurement and mechanical dispersion assessment provide prognostic information and assist in risk stratification. Furthermore, intracardiac echocardiography may have an adjunctive role for the VA ablation by providing real-time visualization of cardiac structures, continuous monitoring of catheter location and early recognition of procedural complications. This review gathers all relevant information that echocardiography may offer prior to VA ablation procedures.

Peak Oxygen Uptake on Cardiopulmonary Exercise Test Is a Predictor for Severe Arrhythmic Events during Three-Year Follow-Up in Patients with Complex Congenital Heart Disease

Patients with congenital heart disease (CHD) are at increased risk for severe arrhythmia and sudden cardiac death (SCD). Although implantable cardioverter defibrillators (ICD) effectively prevent SCD, risk stratification for primary prophylaxis in patients with CHD remains challenging. Patients with complex CHD undergoing CPET were included in this single-center study. Univariable and backwards stepwise multivariable logistic regression models were used to identify variables associated with the endpoint of severe arrhythmic event during three years of follow-up. Cut-off values were established with receiver operating characteristic (ROC) curve analysis. Survival analysis was conducted via Kaplan–Meier plots. Severe Arrhythmia was documented in 97 of 1194 patients (8.1%/3 years). Independent risk factors for severe arrhythmia during follow-up were old age and a low peak oxygen uptake (V.O2peak) on multivariable analysis. Patients with more advanced age and with V.O2peak values of less than 24.9 mL/min/kg were at significantly increased risk for the occurrence of severe arrhythmias during follow-up. The combined analysis of both risk factors yielded an additional benefit for risk assessment. Age at CPET and V.O2peak predict the risk for severe arrhythmic events and should be considered for risk stratification of SCD in patients with complex CHD.

Exercising with a Single Ventricle: Limitations and Therapies

Treatment for Hypoplastic Left Heart Syndrome (HLHS) and other single ventricle conditions requires a series of surgical interventions for long-term survival, typically culminating in the Fontan procedure. The result is an abnormal circulatory physiology with an absence of a sub-pulmonary ventricle. Exercise capacity in the Fontan circulation is often limited and is due to multiple factors, both central and peripheral. Multiple interventions, both pharmacologic and nonpharmacologic, have been studied to attempt to overcome these inherent limitations. This review will focus on the physiology of the exercising Fontan patient and on the interventions aimed at the enhancement of exercise capacity studied thus far.

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.

Lead Extraction at a Pediatric/Congenital Heart Disease Center: The Importance of Patient Age at Implant

OBJECTIVES

This study sought to evaluate the safety and efficacy of transvenous lead extraction (TLE) at a single pediatric/congenital heart disease (CHD) center.

BACKGROUND

Data on TLE in pediatric and CHD patients are limited.

METHODS

Retrospective cohort study evaluating TLE from 2008 to 2019.

RESULTS

A total of 113 patients underwent TLE with 162 leads removed (including 38 high-voltage leads). Median age at lead implantation was 13 years (range 0.6-61.8 years), with a median age at extraction of 21.6 years (6.4-64.3 years). Median lead age was 7.2 years (1.0-35.3 years). Successful extraction occurred in 110 (97%) patients, 159 (98%) leads. Complex extraction was needed for 120 leads; 52 (44%) using laser alone, 27 (23%) mechanical sheath alone, and 21 (18%) using both. Femoral extraction was used for 19 (16%) leads. Risk factors for complex extraction were ≥2 leads extracted (odds ratio: 3.36; 95% confidence interval [CI]: 1.2-9.36; P = 0.021), lead within the right ventricle (odds ratio: 2.8; 95% CI: 1.2-6.5; P = 0.017), and a combination of younger patient age at implant and older lead age at extraction, with patients ≤12 years of age at implant and leads ≥7 years of age having an odds ratio: of 10.1 (95% CI: 2.21-45.9; P = 0.003). Major complications occurred in 5 (4.4%) of patients, with no mortality, but a high incidence of tricuspid valve injury.

CONCLUSIONS

TLE can be performed successfully and safely in a pediatric and CHD center. Patient age at lead implantation, not age at extraction, is an important predictor of needing a complex extraction, with younger patients at implant and older leads at extraction having the highest risk.

Heart Failure Risk Predictions and Prognostic Factors in Adults With Congenital Heart Diseases

In recent decades the number of adults with congenital heart diseases (ACHD) has increased significantly. This entails the need for scrupulous evaluation of the current condition of these patients. The ACHD population is one of the most challenging in contemporary medicine, especially as well-known scales such as the NYHA classification have very limited application. At the moment, there is a lack of universal parameters or scales on the basis of which we can easily capture the moment of deterioration of our ACHD patients' condition. Hence it is crucial to identify factors that are widely available, cheap and easy to use. There are studies showing more and more potential prognostic factors that may be of use in clinical practice: thorough assessment with echocardiography and magnetic resonance imaging (e.g., anatomy, ventricular function, longitudinal strain, shunt lesions, valvular defects, pericardial effusion, and pulmonary hypertension), cardiopulmonary exercise testing (e.g., peak oxygen uptake, ventilatory efficiency, chronotropic incompetence, and saturation) and biomarkers (e.g., N-terminal pro-brain type natriuretic peptide, growth-differentiation factor 15, high-sensitivity troponin T, red cell distribution width, galectin-3, angiopoietin-2, asymmetrical dimethylarginine, and high-sensitivity C-reactive protein). Some of them are very promising, but more research is needed to create a specific panel on the basis of which we will be able to assess patients with specific congenital heart diseases.

The impact of the COVID-19 pandemic on application of European Society of Cardiology (ESC) guidelines for exercise in adults with CHD: a data-based questionnaire

INTRODUCTION

Regular physical activity is safe and effective therapy for adults with CHD and is recommended by European Society of Cardiology guidelines. The COVID-19 pandemic poses enormous challenges to healthcare teams and patients when ensuring guideline compliance. We explored the implications of COVID-19 on physical activity levels in adult CHD patients.

MATERIALS AND METHODS

A data-based questionnaire was distributed to adult CHD patients at a regional tertiary centre from October to November 2020.

RESULTS

Prior to the COVID-19 pandemic, 96 (79.3%) of 125 respondents reported participating in regular physical activity, with 66 (52.8%) meeting target levels (moderate physical activity for at least 150 minutes per week). Commonest motivations for physical activity were general fitness (53.6%), weight loss (36.0%), and mental health benefits (30.4%). During the pandemic, the proportion that met target levels significantly decreased from 52.8% to 40.8% (p = 0.03). The commonest reason was fear of COVID-19 (28.0%), followed by loss of motivation (23.2%) and gym/fitness centre closure (15.2%).

DISCUSSION

The COVID-19 pandemic has negatively impacted exercise levels of adult CHD patients. Most do not meet recommended physical activity levels, mainly attributable to fear of COVID-19. Even before the pandemic, only half of respondents met physical activity guidelines. Availability of online classes can positively impact exercise levels so could enhance guideline compliance. This insight into health perceptions and behaviours of adult CHD patients may help develop quality improvement initiatives to improve physical activity levels in this population.

Risk of sports-related sudden cardiac death in women

Sudden cardiac death (SCD) is a tragic incident accountable for up to 50% of deaths from cardiovascular disease. Sports-related SCD (SrSCD) is a phenomenon which has previously been associated with both competitive and recreational sport activities. SrSCD has been found to occur 5-33-fold less frequently in women than in men, and the sex difference persists despite a rapid increase in female participation in sports. Establishing the reasons behind this difference could pinpoint targets for improved prevention of SrSCD. Therefore, this review summarizes existing knowledge on epidemiology, characteristics, and causes of SrSCD in females, and elaborates on proposed mechanisms behind the sex differences. Although literature concerning the aetiology of SrSCD in females is limited, proposed mechanisms include sex-specific variations in hormones, blood pressure, autonomic tone, and the presentation of acute coronary syndromes. Consequently, these biological differences impact the degree of cardiac hypertrophy, dilation, right ventricular remodelling, myocardial fibrosis, and coronary atherosclerosis, and thereby the occurrence of ventricular arrhythmias in male and female athletes associated with short- and long-term exercise. Finally, cardiac examinations such as electrocardiograms and echocardiography are useful tools allowing easy differentiation between physiological and pathological cardiac adaptations following exercise in women. However, as a significant proportion of SrSCD causes in women are non-structural or unexplained after autopsy, channelopathies may play an important role, encouraging attention to prodromal symptoms and family history. These findings will aid in the identification of females at high risk of SrSCD and development of targeted prevention for female sport participants.

Device-detected non-sustained ventricular tachycardia in adult congenital heart disease without tetralogy of fallot

OBJECTIVES

To evaluate any association between non-sustained ventricular tachycardia (NSVT) detected by intra-cardiac device and clinical outcomes in repaired adult congenital heart disease (ACHD) without tetralogy of Fallot (TOF).

BACKGROUND

NSVT portends a higher risk of serious ventricular tachyarrhythmia in TOF. However its clinical significance when incidentally detected by implantable cardiac device is not well elucidated in non-TOF ACHD cohort.

METHODS

We performed a single center, retrospective, longitudinal follow-up study in repaired ACHD (≥ 18 years) patients without TOF who hosted a pacemaker or automatic implantable cardiac defibrillator (AICD). The cohort was divided based on presence/absence of device detected NSVT. The primary end-point was a composite of sustained ventricular tachycardia (VT), ventricular fibrillation (VF), or sudden cardiac death (SCD).

RESULTS

158 patients [male 56.3%, median (IQR) age of 35 (28-43) years at last follow-up] with longitudinal post-implant follow-up duration of 8 (5-12) years were included. NSVT was detected in 52 (33%) patients. The primary composite end-point was more frequent in NSVT group [11.5% vs. 2.8%; p = 0.04]. Patients with NSVT were i) older at the time of initial implant (age 25 vs. 18 years, p = 0.011) and more frequently demonstrated ii) systemic ventricular dysfunction (44% vs. 26%; p = 0.015), as well as iii) history of ventriculotomy (38% vs. 21%;p = 0.017).

CONCLUSIONS

In our repaired ACHD cohort, we noted a significant association between device-detected-NSVT and the primary composite end-point of sustained VT/VF or SCD. Systemic ventricular dysfunction and history of ventriculotomy were more frequent in the NSVT group and likely constituted the clinical milieu. This article is protected by copyright. All rights reserved.

Avalanches in cardiology

Sudden cardiac death (SCD) accounts for 15%–60% of mortality in patients with heart disease. Generally, this has been attributed to ventricular tachyarrhythmia. However, ventricular tachyarrhythmia has been documented or strongly suspected on clinical grounds in a relatively small proportion of SCD patients (8%–50%). Attempted prophylaxis of SCD by implantation of cardioverter-defibrillator is associated with variable success in different subsets of high-risk cardiac patients (30%–70%). A significant number of SCD, therefore, appear to be due to catastrophic circulatory failure. Multiple interdependent compensatory mechanisms help to maintain circulation in advanced cardiac disease. Rapid, unexpected, and massive breakdown of the compensated state can be precipitated by small and often imperceptible triggers. The initial critical but stable state followed by rapid circulatory failure and death has been considered to be analogous to snow avalanches. It is typically described in patients with left ventricular (LV) dysfunction (ischemic or nonischemic). It is now recognized that SCD can also happen in conditions where the right ventricle (RV) takes the brunt of the hemodynamic load. Advanced pulmonary arterial hypertension and operated patients of tetralogy of Fallot with pulmonary regurgitation are of particular interest to pediatric cardiologists. A large amount of data is available on LV changes and mechanics, while relatively little information is available on the mechanisms of RV adaptation to increased load and RV failure. Whether the triggers and the decompensatory processes are similar for the two ventricles is a moot point. This article highlights the currently available knowledge on the pathophysiology of SCD in RV overload states, with special reference to RV adaptive and decompensatory mechanisms, and therapeutic measures that can potentially interrupt the vicious downward course (cardiac avalanches).