ACC/AHA/HRS 2008 Guidelines for device-based therapy of cardiac rhythm abnormalities. Heart Rhythm. 2008;5:e1-62. [PMID: 18534360 DOI: 10.1016/j.hrthm.2008.04.014]

2024 HRS expert consensus statement on arrhythmias in the athlete: Evaluation, treatment, and return to play

Youth and adult participation in sports continues to increase, and athletes may be diagnosed with potentially arrhythmogenic cardiac conditions. This international multidisciplinary document is intended to guide electrophysiologists, sports cardiologists, and associated health care team members in the diagnosis, treatment, and management of arrhythmic conditions in the athlete with the goal of facilitating return to sport and avoiding the harm caused by restriction. Expert, disease-specific risk assessment in the context of athlete symptoms and diagnoses is emphasized throughout the document. After appropriate risk assessment, management of arrhythmias geared toward return to play when possible is addressed. Other topics include shared decision-making and emergency action planning. The goal of this document is to provide evidence-based recommendations impacting all areas in the care of athletes with arrhythmic conditions. Areas in need of further study are also discussed.

Association between nighttime heart rate and cardiovascular mortality in patients with implantable cardioverter-defibrillator: A cohort study

BACKGROUND

Although studies have shown that an increased resting heart rate measured randomly at a single point of the day has been associated with adverse cardiovascular outcomes, the utility of continuous monitoring of nighttime heart rate (NTHR) has remained largely uninvestigated.

OBJECTIVE

This study aimed to explore the association between NTHR and cardiovascular mortality.

METHODS

The Study of Home Monitoring System Safety and Efficacy in Cardiac Implantable Electronic Device-implanted Patients, which is a prospective cohort study, enrolled patients with implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy defibrillator between 2010 and 2015. Baseline NTHR was measured during the programmed sleep period from 30 to 60 days after implantation. The primary outcome was cardiovascular mortality, fitted by a restricted cubic spline function.

RESULTS

A total of 534 implantable cardioverter-defibrillator recipients with sinus rhythm during the detection window were included in the study. The mean baseline NTHR was 59.6 ± 8.0 beats/min. During the follow-up period of 60.4 ± 21.8 months, 88 (16.5%) patients experienced cardiovascular mortality. After considering potential confounders, a linear association was observed. Each 1 beat/min increase in NTHR was associated with a 7.8%, 10.1%, and 5.7% increase in the risk of cardiovascular mortality in the total population, patients with heart failure, and patients without heart failure, respectively.

CONCLUSION

Continuous monitoring of NTHR may identify patients at high risk of cardiovascular mortality in a timely manner, with the potential for "preemptive" action.

TRIAL REGISTRATION

No. ChiCTR-ONRC-13003695.

Lead Management in Patients with Congenital Heart Disease

Pediatric patients with congenital heart disease present unique challenges when it comes to cardiac implantable electronic devices. Pacing strategy is often determined by patient size/weight and operator experience. Anatomic considerations, including residual shunts, anatomic obstructions and barriers, and abnormalities in the native conduction system, will affect the type of CIED implanted. Given the young age of patients, it is important to have an "eye on the future" when making pacemaker/defibrillator decisions, as one can expect several generator changes, lead revisions, and potential lead extractions during their lifetime.

Overview of Cardiac Arrhythmias and Treatment Strategies

Maintenance of normal cardiac rhythm requires coordinated activity of ion channels and transporters that allow well-ordered propagation of electrical impulses across the myocardium. Disruptions in this orderly process provoke cardiac arrhythmias that may be lethal in some patients. Risk of common acquired arrhythmias is increased markedly when structural heart disease caused by myocardial infarction (due to fibrotic scar formation) or left ventricular dysfunction is present. Genetic polymorphisms influence structure or excitability of the myocardial substrate, which increases vulnerability or risk of arrhythmias in patients. Similarly, genetic polymorphisms of drug-metabolizing enzymes give rise to distinct subgroups within the population that affect specific drug biotransformation reactions. Nonetheless, identification of triggers involved in initiation or maintenance of cardiac arrhythmias remains a major challenge. Herein, we provide an overview of knowledge regarding physiopathology of inherited and acquired cardiac arrhythmias along with a summary of treatments (pharmacologic or non-pharmacologic) used to limit their effect on morbidity and potential mortality. Improved understanding of molecular and cellular aspects of arrhythmogenesis and more epidemiologic studies (for a more accurate portrait of incidence and prevalence) are crucial for development of novel treatments and for management of cardiac arrhythmias and their consequences in patients, as their incidence is increasing worldwide.

Cardiovascular implantable electronic device lead safety: Harnessing real-world remote monitoring data for medical device evaluation

BACKGROUND

Current methods to identify cardiovascular implantable electronic device lead failure include postapproval studies, which may be limited in scope, participant numbers, and attrition; studies relying on administrative codes, which lack specificity; and voluntary adverse event reporting, which cannot determine incidence or attribution to the lead.

OBJECTIVE

The purpose of this study was to determine whether adjudicated remote monitoring (RM) data can address these limitations and augment lead safety evaluation.

METHODS

Among 48,191 actively monitored patients with a cardiovascular implantable electronic device, we identified RM transmissions signifying incident lead abnormalities and, separately, identified all leads abandoned or extracted between April 1, 2019, and April 1, 2021. We queried electronic health record and Medicare fee-for-service claims data to determine whether patients had administrative codes for lead failure. We verified lead failure through manual electronic health record review.

RESULTS

Of the 48,191 patients, 1170 (2.4%) had incident lead abnormalities detected by RM. Of these, 409 patients had administrative codes for lead failure, and 233 of these 409 patients (57.0%) had structural lead failure verified through chart review. Of the 761 patients without administrative codes, 167 (21.9%) had structural lead failure verified through chart review. Thus, 400 patients with RM transmissions suggestive of lead abnormalities (34.2%) had structural lead failure. In addition, 200 patients without preceding abnormal RM transmissions had leads abandoned or extracted for structural failure, making the total lead failure cohort 600 patients (66.7% with RM abnormalities, 33.3% without). Patients with isolated right atrial or left ventricular lead failure were less likely to have lead replacement and administrative codes reflective of lead failure.

CONCLUSION

RM may strengthen real-world assessment of lead failure, particularly for leads where patients do not undergo replacement.

Electrocardiogram Belt guidance for left ventricular lead placement and biventricular pacing optimization

BACKGROUND

Patients with ischemic cardiomyopathy, non-left bundle branch block, or QRS duration <150 ms have a lower response rate to cardiac resynchronization therapy (CRT) than did other indicated patients. The ECG Belt system (EBS) is a novel surface mapping system designed to measure electrical dyssynchrony via the standard deviation of the activation times of the left ventricle.

OBJECTIVES

The objectives of this study were to evaluate the efficacy of the EBS in patients less likely to respond to CRT and to determine whether EBS use in lead placement guidance and device programming was superior to standard CRT care.

METHODS

This was a prospective randomized trial of patients with heart failure and EBS-guided CRT implantation and programming vs standard CRT care. The primary end point was relative change in left ventricular end-systolic volume from baseline to 6 months postimplantation.

RESULTS

A total of 408 patients from centers in Europe and North America were randomized. Although both patients with EBS and control patients had a mean improvement in left ventricular end-systolic volume, there was no significant difference in relative change from baseline (P = .26). While patients with a higher baseline standard deviation of the activation times derived greater left ventricular reverse remodeling, improvement in electrical dyssynchrony did not correlate with the extent of reverse remodeling.

CONCLUSION

The findings of the present study do not support EBS-guided therapy for CRT management of heart failure with reduced ejection fraction.

Factors associated with remote monitoring adherence for cardiovascular implantable electronic devices

BACKGROUND

Professional societies strongly recommend remote monitoring (RM) of all cardiac implantable electronic devices, and higher RM adherence is associated with improved patient outcomes. However, adherence with RM is suboptimal.

OBJECTIVE

The purpose of this study was to better understand factors associated with RM adherence.

METHODS

We linked RM data from the Veterans Affairs National Cardiac Device Surveillance Program to clinical data for patients monitored between October 25, 2018, and October 24, 2020. RM adherence was defined as the percentage of days covered by an RM transmission during the study period. Patients were classified into 3 categories: complete (100% of days covered by an RM transmission), intermediate (above median in patients with <100% adherence), and low (below median in patients with <100% adherence) adherence. We used multivariable logistic regression to examine patient, device, and facility characteristics associated with adherence.

RESULTS

In 52,574 patients, average RM adherence was 71.9%. Only 30.9% (16,224) of patients had complete RM adherence. Black or African American patients had a lower odds of complete RM adherence than white patients (odds ratio 0.88; 95% confidence interval 0.82-0.94), and Hispanic or Latino patients had a lower odds of complete RM adherence (odds ratio 0.79; 95% confidence interval 0.70-0.89) than non-Hispanic or Latino patients. Dementia, depression, and posttraumatic stress disorder were associated with a lower odds of RM adherence.

CONCLUSION

There are significant disparities in RM adherence by race, ethnicity, and neuropsychiatric comorbidities. These findings can inform strategies to improve health equity and ensure that all patients with cardiac implantable electronic devices receive the evidence-based clinical benefits of RM.

Arrhythmias as Presentation of Genetic Cardiomyopathy

There is increasing evidence regarding the prevalence of genetic cardiomyopathies, for which arrhythmias may be the first presentation. Ventricular and atrial arrhythmias presenting in the absence of known myocardial disease are often labelled as idiopathic, or lone. While ventricular arrhythmias are well-recognized as presentation for arrhythmogenic cardiomyopathy in the right ventricle, the scope of arrhythmogenic cardiomyopathy has broadened to include those with dominant left ventricular involvement, usually with a phenotype of dilated cardiomyopathy. In addition, careful evaluation for genetic cardiomyopathy is also warranted for patients presenting with frequent premature ventricular contractions, conduction system disease, and early onset atrial fibrillation, in which most detected genes are in the cardiomyopathy panels. Sudden death can occur early in the course of these genetic cardiomyopathies, for which risk is not adequately tracked by left ventricular ejection fraction. Only a few of the cardiomyopathy genotypes implicated in early sudden death are recognized in current indications for implantable cardioverter defibrillators which otherwise rely upon a left ventricular ejection fraction ≤0.35 in dilated cardiomyopathy. The genetic diagnoses impact other aspects of clinical management such as exercise prescription and pharmacological therapy of arrhythmias, and new therapies are coming into clinical investigation for specific genetic cardiomyopathies. The expansion of available genetic information and implications raises new challenges for genetic counseling, particularly with the family member who has no evidence of a cardiomyopathy phenotype and may face a potentially negative impact of a genetic diagnosis. Discussions of risk for both probands and relatives need to be tailored to their numeric literacy during shared decision-making. For patients presenting with arrhythmias or cardiomyopathy, extension of genetic testing and its implications will enable cascade screening, intervention to change the trajectory for specific genotype-phenotype profiles, and enable further development and evaluation of emerging targeted therapies.

Clinical analysis of temporary pacemaker implantation in 13 children

Background

At present, temporary pacemaker implantation is very common in the treatment of cardiovascular diseases in adults. However, the number of pediatric pacemakers implanted is still relatively small, and relevant research is also far less than that of adults. This study aimed to explore the application of temporary pacemakers in children with acute and critical cardiovascular diseases.

Methods

The clinical data of children with cardiovascular diseases who were treated with temporary pacemakers in Tianjin Children's Hospital from October 2017 to February 2021 were analyzed retrospectively.

Results

A total of 13 children with cardiovascular diseases were included in this study, including 4 males and 9 females, mean age of 71.2±56.3 months, and median body weight of 15.5 kg. There were 9 children with endocardial pacing and 4 children with epicardial pacing. The types of diseases included fulminant myocarditis (n=8), complete atrioventricular block (CAVB; n=1), and arrhythmias after open heart surgery (n=4). The median time from onset to admission was 1.0 days in children with endocardial pacing and there was cardiac arrest in 2 children, heart failure in 9 children, cardiogenic shock in 8 children, and Adams-Stokes attack in 7 children. The median time from admission to implantation of temporary pacemakers was 3.0 h and the operation time was 55.0±19.4 min. All 4 children with epicardial pacing had pacemakers implanted during operation because of CAVB. The pacing mode was VVI mode. The initial perceptual voltage was 1-2 mv, the output voltage was 5v, and the pacing frequency was 70-145 bpm. A total of 11 children reverted to sinus rhythm within 5.0 (1.8-34.0) h and the working time of temporary pacemakers was 134.0 (15.0-191.0) h. There was poor pacing in 2 children and catheter displacement in 1 child during pacing. A total of 12 children were followed up for 20.0±12.5 months and 1 was lost to follow-up. During the follow-up period, the cardiac functions were basically normal and no new arrhythmia appeared.

Conclusions

Temporary pacemakers have the advantage of simple operation, definite effect, and safety which has a remarkable effect in the treatment of acute and critical cardiovascular diseases in children.

Predictive impacts of chronic kidney disease and cardiac sympathetic nervous activity on lethal arrhythmic events in chronic heart failure

BACKGROUND

The clinical implications of chronic kidney disease (CKD) and cardiac sympathetic nervous activity (CSNA) regarding lethal arrhythmic events have not yet been fully elucidated in patients with chronic heart failure (CHF). We hypothesized that the combination of CKD and abnormal CSNA, assessed by 123 I-metaiodobenzylguanidine (123 I-MIBG) scintigraphy, may provide useful prognostic information for lethal arrhythmic events.

METHODS

We studied 165 consecutive hospitalized CHF patients without dialysis. Cardiac 123 I-MIBG scintigraphy was performed in a clinically stable condition, and abnormal CSNA was defined as a late heart-to-mediastinum ratio of <1.6. CKD was defined as an estimated glomerular filtration rate of <60 ml/min/1.73 m2 . We then investigated the incidence of lethal arrhythmic events (sustained ventricular tachyarrhythmia, appropriate implantable cardioverter-defibrillator therapy, or sudden cardiac death).

RESULTS

During a median follow-up of 5.3 years, lethal arrhythmic events were observed in 40 patients (24.2%). The patients were divided into four groups according to the presence of CKD and CSNA abnormality: non-CKD/normal CSNA (n = 52), CKD/normal CSNA (n = 39), non-CKD/abnormal CSNA (n = 33), and CKD/abnormal CSNA (n = 41). Kaplan-Meier analysis showed that CKD/abnormal CSNA had the highest event rate (log-rank p = .004). Additionally, the Cox proportional hazard analysis revealed that CKD/abnormal CSNA was a predictor for lethal arrhythmic events compared with non-CKD/normal CSNA (hazard ratio, 5.368, p = .001). However, the other two groups did not show significant differences compared with the non-CKD/normal CSNA group.

CONCLUSIONS

The combination of CKD and abnormal CSNA, assessed by 123 I-MIBG scintigraphy, had a high predictive value for lethal arrhythmic events in patients with CHF.

Ventricular arrhythmia management in patients with genetic cardiomyopathies

Genetic cardiomyopathies are associated with increased risk for cardiac arrhythmias and sudden cardiac death. The management of ventricular arrhythmias (VAs) in patients with these conditions can be nuanced due to particular disease-based considerations, yet data specifically addressing management in these patients are limited. Here we describe the current evidence-based approach to the management of ventricular rhythm disorders in patients with genetic forms of cardiomyopathy, namely, hypertrophic cardiomyopathy, arrhythmogenic cardiomyopathy, left ventricular noncompaction, and Brugada syndrome, including recommendations from consensus guideline statements when available.

POLYMORPHIC VENTRICULAR TACHYCARDIA DETECTED WITH A SMARTWATCH

“Wearable” devices are a rapidly evolving technology that often can record and store personal healthcare data. We report the case of a 64-year-old woman who presented with a syncopal episode and subsequent cardiac arrest, ultimately requiring a dual-chamber implantable cardioverter defibrillator. Prior to hospitalization, she obtained electrocardiogram recordings using her Apple Watch, due to feeling unwell, and one showed nonsustained polymorphic ventricular tachycardia. Direct-to-consumer electrocardiogram monitors in “wearables” are increasing in popularity and may play a role in the work-up and diagnosis of patients’ symptoms. However, they are not a replacement for healthcare expertise, and their misuse may result in undue anxiety and inappropriate healthcare utilization.

Lyme carditis: An atypical cause of syncope

ABSTRACT

With the rising prevalence of Lyme disease over the last 2 decades comes an increase in cases of Lyme carditis, a consequence of early disseminated infection. This case report focuses on a young man with a complicated case of Lyme carditis that required advanced therapy.

Angiography-guided mid/high septal implantation of ventricular leads in patients with congenital heart disease

BACKGROUND

Conduction system pacing prevents pacing-induced cardiomyopathy, but it can be challenging to perform in patients with congenital heart disease (CHD), and mid/high septal lead implantation is an alternative. This study aimed to assess intraprocedural angiography's utility as a guide for mid/high-septal lead implantation in CHD patients.

METHODS

The study subjects were CHD patients with Class I/IIa indications for permanent pacemaker implantation. To guide septal lead implantation, we performed an intraprocedural right ventricular angiogram in anteroposterior, 40° left anterior oblique, and 30° right anterior oblique. The primary endpoint was the lead tip in the mid/high septum on computed tomography (CT). The secondary endpoints were complications and systemic ventricular function on follow-up.

RESULTS

From January 2008 to December 2018, we enrolled 27 patients (mean age: 30 ± 20 years; M:F 17:10) with CHD (unoperated: 20, operated: 7). The mean paced QRS duration was 131.7 ± 5.8 ms, and CT done in 22/27 patients confirmed the lead tip in the mid-septum in 16, high septum in 5, and apical septum in 1 patient. There were no procedural complications, and during a mean follow-up of 58 ± 35.2 months, there was no significant change in the systemic ventricular ejection fraction (56.4 ± 8.3% vs 53.9 + 5.9%, P = .08). Two patients with Eisenmenger syndrome died because of refractory heart failure.

CONCLUSIONS

Intraprocedural angiography is safe and useful to guide mid/high-septal lead implantation in CHD patients. Mid/high septal lead position preserves systemic ventricular function in patients with CHD during medium-term follow-up.

Inherited and Acquired Rhythm Disturbances in Sick Sinus Syndrome, Brugada Syndrome, and Atrial Fibrillation: Lessons from Preclinical Modeling

Rhythm disturbances are life-threatening cardiovascular diseases, accounting for many deaths annually worldwide. Abnormal electrical activity might arise in a structurally normal heart in response to specific triggers or as a consequence of cardiac tissue alterations, in both cases with catastrophic consequences on heart global functioning. Preclinical modeling by recapitulating human pathophysiology of rhythm disturbances is fundamental to increase the comprehension of these diseases and propose effective strategies for their prevention, diagnosis, and clinical management. In silico, in vivo, and in vitro models found variable application to dissect many congenital and acquired rhythm disturbances. In the copious list of rhythm disturbances, diseases of the conduction system, as sick sinus syndrome, Brugada syndrome, and atrial fibrillation, have found extensive preclinical modeling. In addition, the electrical remodeling as a result of other cardiovascular diseases has also been investigated in models of hypertrophic cardiomyopathy, cardiac fibrosis, as well as arrhythmias induced by other non-cardiac pathologies, stress, and drug cardiotoxicity. This review aims to offer a critical overview on the effective ability of in silico bioinformatic tools, in vivo animal studies, in vitro models to provide insights on human heart rhythm pathophysiology in case of sick sinus syndrome, Brugada syndrome, and atrial fibrillation and advance their safe and successful translation into the cardiology arena.

Clinical impact of long PR-interval and presence of late gadolinium enhancement on hospitalized patients with non-ischemic heart failure

BACKGROUND

The combination of electrical and structural remodeling may have a strong effect on the prognosis of non-ischemic heart failure (HF). We aimed to clarify whether prolonged PR-interval and the presence of late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMR) influence the outcomes of patients with non-ischemic HF.

METHODS

We studied 262 consecutive hospitalized patients with non-ischemic HF. In a clinically stable condition, a 12-lead electrocardiogram and CMR were performed, and the clinical characteristics and outcomes were investigated.

RESULTS

During the follow-up of 967.7 ± 851.8 days, there were 68 (25.9%) cardiac events (HF or sudden death, re-hospitalization due to HF, or ventricular tachyarrhythmias). In a multivariable analysis, a median rate-adjusted PR (PRa)-interval of ≥173.5 ms and the presence of LGE were associated with cardiac events with a hazard ratio of 1.690 and 2.045 (p = .044 and p = .006, respectively). Study subjects were then divided into four groups based on long (≥173.5 ms) or short (<173.5 ms) PRa-interval and LGE status: short PRa/non-LGE (n = 80), long PRa/non-LGE (n = 72), short PRa/LGE (n = 51), and long PRa/LGE (n = 59). Cardiac events were 16.2% in short PRa/non-LGE, 25.0% in long PRa/non-LGE, 27.4% in short PRa/LGE, and 38.9% in long PRa/LGE (p = .026), respectively. The multivariable Cox proportional hazard analysis showed that long PRa/LGE was an independent predictor for cardiac events compared to short PRa/non-LGE (hazard ratio, 3.378, p = .001).

CONCLUSIONS

The combination of a long PRa-interval and the presence of LGE provide a better predictive value of cardiac events in non-ischemic HF.

2019 HRS expert consensus statement on evaluation, risk stratification, and management of arrhythmogenic cardiomyopathy: Executive summary

Arrhythmogenic cardiomyopathy (ACM) is an arrhythmogenic disorder of the myocardium not secondary to ischemic, hypertensive, or valvular heart disease. ACM incorporates a broad spectrum of genetic, systemic, infectious, and inflammatory disorders. This designation includes, but is not limited to, arrhythmogenic right/left ventricular cardiomyopathy, cardiac amyloidosis, sarcoidosis, Chagas disease, and left ventricular noncompaction. The ACM phenotype overlaps with other cardiomyopathies, particularly dilated cardiomyopathy with arrhythmia presentation that may be associated with ventricular dilatation and/or impaired systolic function. This expert consensus statement provides the clinician with guidance on evaluation and management of ACM and includes clinically relevant information on genetics and disease mechanisms. PICO questions were utilized to evaluate contemporary evidence and provide clinical guidance related to exercise in arrhythmogenic right ventricular cardiomyopathy. Recommendations were developed and approved by an expert writing group, after a systematic literature search with evidence tables, and discussion of their own clinical experience, to present the current knowledge in the field. Each recommendation is presented using the Class of Recommendation and Level of Evidence system formulated by the American College of Cardiology and the American Heart Association and is accompanied by references and explanatory text to provide essential context. The ongoing recognition of the genetic basis of ACM provides the opportunity to examine the diverse triggers and potential common pathway for the development of disease and arrhythmia.

Association of the Obesity Paradox With Objective Physical Activity in Patients at High Risk of Sudden Cardiac Death

OBJECTIVE

To investigate the obesity paradox and its interrelationship with objective physical activity (PA) in patients at high risk of sudden cardiac death.

METHODS

A total of 782 patients with implantable cardioverter-defibrillators/cardiac resynchronization therapy defibrillators in the Study of Home Monitoring System Safety and Efficacy in Cardiac Implantable Electronic Device-Implantable Patients registry were retrospectively analyzed and grouped by body mass index (BMI) (kg/m2): normal weight (18.5 ≤ BMI < 25) and overweight or class I obesity (25 ≤ BMI < 35). PA was measured with home monitoring and categorized into 4 groups (Q1-Q4) by the baseline quartiles. The main endpoint was all-cause mortality.

RESULTS

During a mean follow-up period of 59.9 ± 21.9 months, 182 all-cause mortality events occurred. Mortality tended to be lower in overweight and obesity patients (18.9% vs 25.1%, P = 0.061) and decreased by PA quartiles (44.1% vs 22.6% vs 15.3% vs 11.2%, Q1-Q4, P < 0.001). Multivariate Cox analysis indicated BMI (hazard ratio, 0.918; 95% confidence interval, 0.866-0.974; P = 0.004) and PA (0.436, 0.301-0.631, Q2 vs Q1; 0.280, 0.181-0.431, Q3 vs Q1; 0.257, 0.158-0.419, Q4 vs Q1; P < 0.001 for all) were associated with reduced risk. The obesity paradox was significant in the total cohort (log rank P = 0.049) and low PA group (log rank P = 0.010), but disappeared in the high PA group (log rank P = 0.692). Dose-response curves showed a significant reduction in risk with low-moderate PA, and the pattern varied between different BMI groups.

CONCLUSIONS

The obesity paradox only persisted in physically inactive patients. PA might be related to the development of the obesity paradox.

The Proportion of Women Authors and the Inclusion of Sex and Gender Content Among the American College of Cardiology Clinical Practice Guidelines, 2008-2018

Background: Sex and gender, two important factors affecting health care, should be routinely taken into consideration in clinical practice. Members of the Sex and Gender Health Collaborative Scholarship Committee reviewed clinical guidelines published by the American College of Cardiology (ACC) from 2008 to 2018 to determine if the number of women authors on the writing committee influenced the presence of sex- and gender-specific content and recommendations in each guideline. Methods: We reviewed 33 ACC clinical guidelines from 2008 to 2018 and determined the number of women authors on the writing committee for each guideline. We then reviewed each guideline to identify specific content on sex and/or gender differences as it pertained to the guideline's subject cardiac condition. Results: The median proportion of women authors among the 33 ACC guidelines was 22.2% (interquartile range 4.4-81.1). Only two guidelines (6%) had writing committees with >50% women authors. Overall, 25 of 33 guidelines (75.8%) contained sex and gender content; however, the depth and detail of the sex and gender content varied widely among guidelines. The proportion of women authors was not associated with the presence of sex- and gender-specific content. Conclusions: Our findings demonstrate continued gender disparities in authorship, and changes should be made to increase the inclusion of women in clinical practice guideline writing committees. We propose selecting a sex and gender champion for guideline writing committees and/or including a specific section on sex- and gender-related content in each guideline to ensure inclusion of sex- and gender-specific recommendations in clinical guidelines.

Prognostic value of late gadolinium enhancement in cardiac MRI of non-ischemic dilated cardiomyopathy patients

Background

The role of late gadolinium enhancement (LGE) in cardiac MRI (CMR) as prognostic marker in non-ischemic dilated cardiomyopathy (NIDCM) is evolving.

Objective

To study the effect of LGE in the prognosis of NIDCM patients.

Methods

112 consecutive NIDCM patients, who underwent CMR, were prospectively followed up for 745 ± 320 days. Primary end point was occurrence of MACE {composite of all-cause mortality, resuscitated cardiac arrest, sustained ventricular tachycardia (VT)/appropriate ICD shock, heart failure (HF) hospitalization}.

Results

LGE was present in 44 out of 112 patients (39%). The primary end point (MACE) was significantly higher in LGE + ve group compared to the LGE –ve group (72.7% vs. 29.4%; p < 0.0001). Similarly, cardiac mortality (9.1% vs 2.9%; p < 0.049), VT (13.6% vs. 2.9%; p < 0.031), HF hospitalization (63.6% vs. 30.9%; p < 0.001) were significantly more in LGE + ve group. In univariate model, LGE demonstrated the strongest association with MACE (Hazard ratio [HR] = 2.96 [95% CI 1.685 to 5.201; p < 0.0001). LGE extent of >14% of LV predicted MACE with 90.6% sensitivity and 86% specificity. HR of LGE extent >14% of LV for MACE is 6.12; p < 0.01. LGE was associated with MACE irrespective of its location, pattern or distribution. Multivariate model showed LGE and its extent >14% of LV volume were strongest predictor of MACE.

Conclusion

LGE and its extent >14% predicts adverse cardiac events in NIDCM irrespective of LVEF and LGE location, pattern or distribution. This study emphasises the role of CMR in risk stratification of NIDCM patients and guiding therapy.

Pacemaker Implantation in Neonates and Infants: Favorable Outcomes with Epicardial Pacing Systems

The implantation of pacemakers (PM) in neonates and infants requires particular consideration of small body size, marked body growth potential, and the decades of future pacing therapy to be expected. The aim of this study is to quantify the complications of implantation and outcome occurring at our center and to compare these with other centers. Retrospective analysis of 52 consecutive patients undergoing PM implantation at a single tertiary care center within the first year of life. PMs were implanted at a median age of 3 months (range 0-10 months). Structural heart defects were present in 44 of 52 patients. During a median follow-up time of 40.4 months (range 0.1-114 months), measurements for sensing, pacing thresholds, and lead impedance remained stable. No adverse pacing effect was observed in left ventricular function or dimensions over time. There were 20 reoperations in 13 patients at a median time of 4.7 years (range 0.05-8.2 years) after implantation, for end of battery life (n = 10), lead dysfunction (n = 3), device dislocation (n = 3), infection (n = 3), and diaphragmatic paresis (n = 1). No PM-related mortality occurred. Epicardial pacemaker implantation in neonates and infants is an invasive but safe and effective procedure with a relatively low risk of complications. Our current implantation technique and the use of bipolar steroid-eluting electrodes, which we prefer to implant on the left ventricular apex, lead to favorable long-term results.

The Role of Telecardiology in Dealing with Patients with Cardiac Rhythm Disorders in Family Medicine - Systematic Review

PURPOSE

Heart rhythm disorders (HRD) are often present in patients visiting their family physician (FP). Dealing with their problems is not always simple, efficient and cost effective. The aim of this paper is to review the existing literature about the use and experience of telecardiology in patients experiencing HRD.

METHODS

We conducted a review of literature in PubMed biographical databases (MeSH thesaurus), Web of Science and Cochrane, between 1995 and 2019. We included original articles in English that describe the use of telecardiology at primary and secondary healthcare levels. Exclusion criteria are those publications that discuss heart failure or observation of the activity of pacemakers or defibrillators and the age of patients under 18 years. A total of 19 papers met the inclusion criteria, thirteen of them were original scientific articles and we included them in the analysis.

RESULTS

Use of telemedicine can shorten the time from diagnosis to the necessary treatment (2/13), telemedicine can reduce mortality in patients with acute myocardial infarction (4/13), it can shorten the time to diagnose atrial fibrillations (4/13), it can help determine the diagnosis for patients complaining about heart rhythm disorders which were not detected on the standard ECG recording (2/13) and can also help identify cardiac causes for syncope or collapse (2/13). All studies have confirmed that the use of telecardiology significantly reduces the number of unnecessary referrals to a cardiologist or hospitalization, and shortens the time needed to treat patients with life-threatening conditions.

CONCLUSION

The use of telecardiological techniques increases the quality and safety of work in managing patients with cardiovascular disease in FP practice. Usage of telecardiologic devices can also save money and bridge the gap between the primary and secondary healthcare levels.

Effect of new and persistent left bundle branch block after transcatheter aortic valve replacement on long-term need for pacemaker implantation

Cardiac conduction abnormalities, including left bundle branch block (LBBB), are common following transcatheter aortic valve replacement (TAVR). This study assessed the incidence and outcomes of new or widening persistent LBBB following TAVR. Data regarding 550 consecutive patients undergoing TAVR between 2012 and 2016 at our institution were retrospectively reviewed. Both 30-day and 1-year outcomes of patients with isolated new or worsening LBBB following TAVR were reviewed. Fifty-two patients (9.5%) developed new or worsening LBBB. Six of the 52 (11.5%) patients received a permanent pacemaker (PPM) for LBBB prior to discharge. For patients discharged home following TAVR without a PPM, the 1-year PPM requirement was 15.2% in patients with new or worsening LBBB compared to 4.5% in patients without new or worsening LBBB (P = 0.01). One-year mortality rates for patients who did not have a new PPM placed before discharge were 15.2% in patients with new or worsening LBBB, 13.9% in patients without new or worsening LBBB, and 11.9% in patients with preoperative PPMs (P = 0.81). Patients with new or worsening persistent LBBB discharged without a PPM experience a higher requirement for PPM implantation in the year following TAVR compared to patients without new or worsening persistent LBBB.

An association between right ventricular dysfunction and sudden cardiac death

BACKGROUND

The effectiveness of severely reduced left ventricular ejection fraction (LVEF <35%) as a predictor of sudden cardiac death (SCD) has diminished, and improvements in risk stratification await discovery of novel markers. Right ventricular (RV) abnormalities can be observed in conditions such as chronic obstructive pulmonary disease and sleep apnea, which have been linked to SCD.

OBJECTIVE

The purpose of this study was to evaluate whether RV abnormalities were associated with SCD after accounting for LVEF and other patient characteristics.

METHODS

In a large, prospective ongoing community-based study of SCD in the Portland, Oregon, metropolitan area, SCD cases (age ≥18 years; 2002-2014) were compared to controls with coronary artery disease but no SCD. Using a novel archive of digital echocardiograms, a standardized approach was used to evaluate RV basal diameter, RV end-diastolic area, and right ventricular fractional area change (RVFAC).

RESULTS

A total of 350 subjects were studied, including 81 SCD cases (age 68.7 ± 13.6 years; 73% male) and 269 controls (age 66.5 ± 10.2 years; 69% male). In multivariate analysis, RVFAC was significantly associated with SCD (odds ratio 1.14 for each 5% decrease; 95% confidence interval 1.03-1.25; P = .01). When modeled with LVEF ≤35%, RVFAC ≤35% was significantly associated with increased risk of SCD. Individuals with both left ventricular and RV dysfunction had a 3× higher odds of SCD than those with neither (odds ratio 3.19; 95% confidence interval 1.33-7.68; P = .01).

CONCLUSION

RV dysfunction was associated with a significantly increased risk of SCD independent of LVEF and, when combined with LVEF, had additive effects on SCD risk.

Pearson marrow-pancreas syndrome with cardiac conduction abnormality necessitating prophylactic pacemaker implantation

Pearson marrow-pancreas syndrome (PS), an exceedingly rare mitochondrial disorder, involves multiple systems including hematologic system and pancreas. Other mitochondrial disorders have been associated with progressive infrahisian block but this has not yet been described as a major feature of PS. We report a 7-year-old girl with classical features of PS and cardiac conduction defect. Her electrocardiogram revealed QRS prolongation with right bundle and left anterior fascicular blocks. Follow-up Holter revealed bifascicular block, alternating left and right bundle branch blocks, supraventricular tachycardia (with alternating bundles), and suspicion for nonsustained ventricular tachycardia. She underwent successful transvenous single-chamber ventricular pacemaker.

Iron overload and arrhythmias: Influence of confounding factors

Arrhythmias as a cardiac complication of iron overload (IO) have been well described for decades in the clinical literature. They are assumed to be directly associated with the myocardial accumulation of iron. However, the influence of heart failure and elevated oxidative stress, which are major arrhythmogenic confounding factors associated with IO on arrhythmias, has not been critically reviewed in the published literature. A comprehensive narrative review of published articles in PubMed was conducted to address the influence of confounding factors of IO on arrhythmias. The previous data may have been largely confounded by the other cardiac complications of IO, particularly heart failure. The previous studies on IO-related arrhythmias lack proper age-gender-matched control subjects and/or comparison groups with properly controlled confounding factors to assess accurately their etiology and clinical significance. Given the above considerations, further mechanistic investigations to clarify the etiology and clinical relevance of IO-induced arrhythmias are needed. In addition, investigations to develop arrhythmia management strategy specific to IO, are warranted.

Predictive value of rapid-rate non-sustained ventricular tachycardia in the occurrence of appropriate implantable cardioverter-defibrillator therapy

PURPOSE

Rapid-rate non-sustained ventricular tachycardia (RR-NSVT) that meets detection criteria but terminates itself before the delivery of implantable cardioverter-defibrillator (ICD) therapy is not rare in routine ICD interrogation. Whether sustained ventricular tachycardia/fibrillation will occur in a short time after RR-NSVT has not been fully elucidated.

METHODS

Clinical features and follow-up data of 828 ICD patients with home monitoring were retrospectively collected. RR-NSVT characteristics and time interval between the first episode of RR-NSVT and subsequent appropriate ICD therapy were analyzed.

RESULTS

During a mean follow-up of 44.75 ± 20.87 months, 335 episodes of RR-NSVT were documented in 145 patients. A total of 119 patients had both RR-NSVT and appropriate ICD therapy. In multivariate COX regression models, RR-NSVT was an independent predictor of appropriate ICD therapy (HR 7.599, 95%CI 5.926-9.745, P < 0.001), appropriate shock (HR 6.222, 95%CI 4.667-8.294, P < 0.001), and all-cause mortality (HR 2.156, 95%CI 1.499-3.099, P < 0.001). Appropriate ICD therapy was administered after the first RR-NSVT episode in 101 patients, with a median interval of 21 days. Compared to RR-NSVT with appropriate ICD therapy occurring beyond 21 days, RR-NSVT within 21 days prior to appropriate ICD therapy had a longer median duration time (14 s vs. 12 s, P = 0.013), but without significant difference in mean RR interval at initial detection and mean RR interval after episode termination.

CONCLUSIONS

Rapid-rate non-sustained VT was an independent predictor of appropriate ICD therapy and all-cause mortality. The presence of RR-NSVT should be considered a possible herald of more serious cardiac events in ICD patients.

2019 HRS expert consensus statement on evaluation, risk stratification, and management of arrhythmogenic cardiomyopathy

Arrhythmogenic cardiomyopathy (ACM) is an arrhythmogenic disorder of the myocardium not secondary to ischemic, hypertensive, or valvular heart disease. ACM incorporates a broad spectrum of genetic, systemic, infectious, and inflammatory disorders. This designation includes, but is not limited to, arrhythmogenic right/left ventricular cardiomyopathy, cardiac amyloidosis, sarcoidosis, Chagas disease, and left ventricular noncompaction. The ACM phenotype overlaps with other cardiomyopathies, particularly dilated cardiomyopathy with arrhythmia presentation that may be associated with ventricular dilatation and/or impaired systolic function. This expert consensus statement provides the clinician with guidance on evaluation and management of ACM and includes clinically relevant information on genetics and disease mechanisms. PICO questions were utilized to evaluate contemporary evidence and provide clinical guidance related to exercise in arrhythmogenic right ventricular cardiomyopathy. Recommendations were developed and approved by an expert writing group, after a systematic literature search with evidence tables, and discussion of their own clinical experience, to present the current knowledge in the field. Each recommendation is presented using the Class of Recommendation and Level of Evidence system formulated by the American College of Cardiology and the American Heart Association and is accompanied by references and explanatory text to provide essential context. The ongoing recognition of the genetic basis of ACM provides the opportunity to examine the diverse triggers and potential common pathway for the development of disease and arrhythmia.

Trends in Hospital Admissions for and Readmissions After Cardiac Implantable Electronic Device Procedures in the United States: An Analysis From 2010 to 2014 Using the National Readmission Database

OBJECTIVE

To evaluate inpatient trends in de novo complete cardiac implantable electronic device (CIED) procedures and subsequent all-cause 30-day readmissions in the United States.

PATIENTS AND METHODS

We accessed the National Readmission Database to identify CIED implantation-related hospitalizations between January 1, 2010, and December 31, 2014, using International Classification of Diseases, Ninth Revision, Clinical Modification procedure codes. In-hospital mortality and postprocedure all-cause 30-day readmissions were also analyzed.

RESULTS

During the study period, a total of 800,250 CIED implantation hospitalizations were identified across the United States, with an in-hospital mortality rate of 0.9% (7423 of 800,250) and a 29% decrease in CIED-related index hospitalizations (188,086 in 2010 vs 134,276 in 2014). The all-cause 30-day readmission rate for the entire cohort was 13% (106,505 of 800,250), decreasing from 14% (26,134 of 188,085) in 2010 to only 13% (17,154 of 134,276) by 2014. Dual-chamber pacemakers were the most frequently implanted in-hospital CIEDs (473,615 of 800,250 [59%]). The most common cause for readmission was heart failure exacerbation, which remained unchanged over the study period.

CONCLUSION

Our data reveal a steady decline in overall in-hospital CIED implantations and only a modest decline in readmission rates. The cause for this decline may be an impact of medical and regulatory changes guiding CIED implantations, but it deserves further investigation.

Quality assessment in Belgian arrhythmology: the Belgian heart rhythm association (BeHRA) databases

This report presents and discusses, on behalf of the Belgian College of Cardiology, the evolution of the peer review process in arrhythmology, focussing on pacemaker implantation. Data from the last 22 years are compared. The national annual increase in implants is around 1%, clinical patient characteristics remained stable over the years while dual chamber pacing was proportionally increasing. Analyses of the normalised sick sinus and complete atrioventricular block ratios revealed a quite homogenous practice between centres and patient district with the only exception of the two more crowded districts. Battery longevity and infection rate were also assessed. With an incidence of 1/1000 device-years follow-up, Belgium remains below accepted European levels.

Patients’ Perspectives on End-Of-Life Issues and Implantable Cardioverter Defibrillators

Increasing numbers of cardiovascular patients are receiving implantable cardioverter defibrillators (ICDs) for primary prevention of sudden cardiac death (SCD). This report examines patients’ perspectives on related end-of-life issues. Using a grounded theory approach, audiotaped, semi-structured interviews were undertaken with 30 participants from two ICD referral centres in southwestern Ontario (24 who accepted an ICD and 6 who declined). Interview transcripts, verification with interviewees, researcher memos, published literature, and participant demographics were analyzed using NVivo7. Most participants were male, had comorbidities and an ejection fraction of less than 30 percent, and ranged in age from 26 to 87. Consensus was reached by three research team members on three main themes: quality versus quantity of life, preferred mode of death, and the technical realities of the ICD. The ICD was considered in relation to both quantity and quality of life. Most participants focused on the prevention of SCD, not the implications of the ICD for death by any other cause. Participants advocated for incorporating the ICD into advance care planning. Our findings have implications for the development of advance care plans and education of health professionals.

Differential prognosis of vasospastic angina according to presentation with sudden cardiac arrest or not: Analysis of the Korean Health Insurance Review and Assessment Service

BACKGROUND

The long-term prognosis of vasospastic angina (VSA) patients presenting with aborted sudden cardiac death (ASCD) is still unknown. We sought to compare the long-term clinical outcomes between VSA patients presenting with and without ASCD by retrospective analysis of a nationwide population-based database.

METHODS

A total of 6972 patients in the Health Insurance Review and Assessment database who were hospitalized in the intensive care unit with VSA between July 1, 2007 and May 31, 2015 were enrolled. Primary outcome was the composite of cardiac arrest and acute myocardial infarction after discharge.

RESULTS

Five hundred ninety-eight (8.6%) VSA patients presented with ASCD. On inverse probability of treatment weighting, ASCD patients had a significantly increased risk of the composite of cardiac arrest and acute myocardial infarction (adjusted hazard ratio, 2.52; 95% confidence interval, 1.72-3.67; p < 0.001) during the median follow-up duration of 4 years. The association of ASCD presentation with a worse outcome in terms of primary outcome was consistent across various subgroups, including comorbidity type and use of vasodilators (all p-values for interaction: non-significant). ASCD patients treated with an implantable cardioverter defibrillator (ICD) had a lower incidence of the composite of cardiac arrest and acute myocardial infarction during follow-up than those without an ICD (p = 0.009).

CONCLUSIONS

VSA patients that present with ASCD are at increased risk of cardiac arrest or myocardial infarction during long-term follow-up despite adequate vasodilator therapy. An ICD is a potential therapeutic option for secondary prevention.

Cardiac sarcoidosis and ventricular arrhythmias. A rare association of a rare disease. A retrospective cohort study from the National Inpatient Sample and current evidence for management

BACKGROUND

Sarcoidosis is an increasingly recognized multi-systemic condition. Cardiac sarcoidosis is associated with ventricular arrhythmias and higher mortality rates. Little epidemiological data is available regarding the disease and associated ventricular arrhythmias.

METHODS

Data from the National Inpatient Sample (NIS) database 2012-2014, were reviewed. Dis-charges associated with sarcoidosis were identified as the target population using relevant ICD-9-CM codes. Primary outcome was a diagnosis of ventricular tachycardia (VT) in the sarcoidosis population. Secondary outcomes include rate of ventricular fibrillation (VF) and cardiac arrest. Subgroup analyses were performed to examine the association of VT with multiple potential confounding clinical variables.

RESULTS

Of 18,013,878 health encounters, 46,289 (0.26%) subjects had a diagnosis of sarcoidosis. VT and VF were more prevalent among patients with sarcoidosis compared to those without a diagnosis of sarcoidosis (2.29% vs. 1.22%; p < 0.001 and 0.25% vs. 0.21%; p < 0.001, respectively). Sarcoidosis was also associated with a higher prevalence of cardiac arrest (0.72% vs. 0.6%; p < 0.001). In unadjusted analyses, all examined comorbidities were significantly more common in those with sar-coidosis, including diabetes mellitus (31.6% vs. 21.25%; p < 0.001), hypertension (65.2% vs. 51.74%; p < 0.001), chronic kidney disease (21.09% vs. 14.02%; p < 0.001), heart failure (24.87% vs. 15%; p < 0.001) and acute coronary syndrome (4.32% vs. 3.35%; p < 0.001).

CONCLUSIONS

The present study showed that sarcoidosis was associated with increased rates of ven-tricular tachyarrhythmia, which can affect the overall disease morbidity and mortality.

High-grade atrioventricular block

Atrioventricular (AV) block is an AV conduction disorder that can manifest in various settings, with varying symptomaticity and severity. The electrocardiogram is a key diagnostic tool for management, and careful interpretation is necessary to institute the correct management. We described two cases of patients with bradycardia due to AV blocks and discussed the electrocardiogram interpretation and management.

A case of atenolol-induced sinus node dysfunction presenting as escape-capture bigeminy

Medications that are routinely used in clinical practice to treat hypertension such as beta blockers or non-dihydropyridine calcium channel blockers can depress sinus node function, resulting in symptoms and electrocardiographic changes consistent with sinus node dysfunction. In some patients, medications are potentially a reversible cause of apparent sinus node dysfunction. We report a patient who was taking atenolol for hypertension presented with recurrent near syncopal spells due to atenolol-induced sinus node dysfunction manifested in the form of an interesting and rare arrhythmia known as Escape-capture bigeminy.

Haemodynamic Monitoring Devices in Heart Failure: Maximising Benefit with Digitally Enabled Patient Centric Care

ICDs and resynchronisation devices are routinely implanted in patients with heart failure for primary prevention of sudden cardiac death or to treat the condition. The addition of device features and algorithms that directly or indirectly monitor cardiac haemodynamics to assess heart failure status can provide additional benefit by treating heart failure more continuously. Established and emerging devices and sensors aimed at treating or measuring cardiac haemodynamics represent the next era of heart failure disease management. Digitally enabled models of heart failure care, based on frequent haemodynamic measurements, will increasingly involve patients in their own disease management. Software tools and services tailored to provide patients with personalised information to guide diet, activity, medications and haemodynamic management offer an unprecedented opportunity to improve patient outcomes. This will enable physicians to care for larger populations because management will be exception based, automated and no longer depend on one-to-one patient and physician interactions.

Friedreich's ataxia: clinical features, pathogenesis and management

INTRODUCTION

Friedreich's ataxia is the most common inherited ataxia.

SOURCES OF DATA

Literature search using PubMed with keywords Friedreich's ataxia together with published papers known to the authors.

AREAS OF AGREEMENT

The last decade has seen important advances in our understanding of the pathogenesis of disease. In particular, the genetic and epigenetic mechanisms underlying the disease now offer promising novel therapeutic targets.

AREAS OF CONTROVERSY

The search for effective disease-modifying agents continues. It remains to be determined whether the most effective approach to treatment lies with increasing frataxin protein levels or addressing the metabolic consequences of the disease, for example with antioxidants.

AREAS TIMELY FOR DEVELOPING RESEARCH

Management of Freidreich's ataxia is currently focussed on symptomatic management, delivered by the multidisciplinary team. Phase II clinical trials in agents that address the abberrant silencing of the frataxin gene need to be translated into large placebo-controlled Phase III trials to help establish their therapeutic potential.