2023 HRS/APHRS/LAHRS guideline on cardiac physiologic pacing for the avoidance and mitigation of heart failure.

Cardiac physiologic pacing (CPP), encompassing cardiac resynchronization therapy (CRT) and conduction system pacing (CSP), has emerged as a pacing therapy strategy that may mitigate or prevent the development of heart failure (HF) in patients with ventricular dyssynchrony or pacing-induced cardiomyopathy. This clinical practice guideline is intended to provide guidance on indications for CRT for HF therapy and CPP in patients with pacemaker indications or HF, patient selection, pre-procedure evaluation and preparation, implant procedure management, follow-up evaluation and optimization of CPP response, and use in pediatric populations. Gaps in knowledge, pointing to new directions for future research, are also identified.

Intracranial bleeding and associated outcomes in atrial fibrillation patients undergoing percutaneous left atrial appendage occlusion: Insights from National Inpatient Sample 2016-2020.

Background: Percutaneous left atrial appendage occlusion (LAAO) has proved to be a safer alternative for long-term anticoagulation; however, patients with a history of intracranial bleeding were excluded from large randomized clinical trials. Objective: The purpose of this study was to determine outcomes in atrial fibrillation (AF) patients with a history of intracranial bleeding undergoing percutaneous LAAO. Methods: National Inpatient Sample and International Classification of Diseases, Tenth Revision, codes were used to identify patients with AF who underwent LAAO during the years 2016-2020. Patients were stratified based on a history of intracranial bleeding vs not. The outcomes assessed in our study included complications, in-hospital mortality, and resource utilization. Result: A total of 89,300 LAAO device implantations were studied. Approximately 565 implantations (0.6%) occurred in patients with a history of intracranial bleed. History of intracranial bleeding was associated with a higher prevalence of overall complications and in-patient mortality in crude analysis. In the multivariate model adjusted for potential confounders, intracranial bleeding was found to be independently associated with in-patient mortality (adjusted odds ratio [aOR] 4.27; 95% confidence interval [CI] 1.68-10.82); overall complications (aOR 1.74; 95% CI 1.36-2.24); prolonged length of stay (aOR 2.38; 95% CI 1.95-2.92); and increased cost of hospitalization (aOR 1.28; 95% CI 1.08-1.52) after percutaneous LAAO device implantation. Conclusion: A history of intracranial bleeding was associated with adverse outcomes after percutaneous LAAO. These data, if proven in a large randomized study, can have important clinical consequences in terms of patient selection for LAAO devices.

2023 HRS/APHRS/LAHRS guideline on cardiac physiologic pacing for the avoidance and mitigation of heart failure.

Cardiac physiologic pacing (CPP), encompassing cardiac resynchronization therapy (CRT) and conduction system pacing (CSP), has emerged as a pacing therapy strategy that may mitigate or prevent the development of heart failure (HF) in patients with ventricular dyssynchrony or pacing-induced cardiomyopathy. This clinical practice guideline is intended to provide guidance on indications for CRT for HF therapy and CPP in patients with pacemaker indications or HF, patient selection, pre-procedure evaluation and preparation, implant procedure management, follow-up evaluation and optimization of CPP response, and use in pediatric populations. Gaps in knowledge, pointing to new directions for future research, are also identified.

Outcomes of percutaneous left atrial appendage occlusion device implantation in atrial fibrillation patients based on underlying stroke risk.

AIMS: To determine outcomes in atrial fibrillation patients undergoing percutaneous left atrial appendage occlusion (LAAO) based on the underlying stroke risk (defined by the CHA2DS2-VASc score). METHODS AND RESULTS: Data were extracted from the National Inpatient Sample for calendar years 2016-20. Left atrial appendage occlusion implantations were identified on the basis of the International Classification of Diseases, 10th Revision, Clinical Modification code of 02L73DK. The study sample was stratified on the basis of the CHA2DS2-VASc score into three groups (scores of 3, 4, and ≥5). The outcomes assessed in our study included complications and resource utilization. A total of 73 795 LAAO device implantations were studied. Approximately 63% of LAAO device implantations occurred in patients with CHA2DS2-VASc scores of 4 and ≥5. The crude prevalence of pericardial effusion requiring intervention was higher with increased CHA2DS2-VASc score (1.4% in patients with a score of ≥5 vs. 1.1% in patients with a score of 4 vs. 0.8% in patients with a score of 3, P < 0.01). In the multivariable model adjusted for potential confounders, CHA2DS2-VASc scores of 4 and ≥5 were found to be independently associated with overall complications [adjusted odds ratio (aOR) 1.26, 95% confidence interval (CI) 1.18-1.35, and aOR 1.88, 95% CI 1.73-2.04, respectively] and prolonged length of stay (aOR 1.18, 95% CI 1.11-1.25, and aOR 1.54, 95% CI 1.44-1.66, respectively). CONCLUSION: A higher CHA2DS2-VASc score was associated with an increased risk of peri-procedural complications and resource utilization after LAAO. These findings highlight the importance of patient selection for the LAAO procedure and need validation in future studies.

Exploratory use of intraprocedural transesophageal echocardiography to guide implantation of the leadless pacemaker.

Background: Fluoroscopy is the standard tool for transvenous implantation of traditional and leadless pacemakers (LPs). LPs are used to avoid complications of conventional pacemakers, but there still is a 6.5% risk of major complications. Mid-right ventricular (RV) septal device implantation is suggested to decrease the risk, but helpful cardiac landmarks cannot be visualized under fluoroscopy. Transesophageal echocardiography (TEE) is an alternative intraprocedural imaging method. Objective: The purpose of this study was to explore the spatial relationship of the LP to cardiac landmarks via TEE and their correlations with electrocardiographic (ECG) parameters, and to outline an intraprocedural method to confirm mid-RV nonapical lead positioning. Methods: Fifty-six patients undergoing implantation of LP with TEE guidance were enrolled in the study. Device position was evaluated by fluoroscopy, ECG, and TEE. Distances between the device and cardiac landmarks were measured by TEE and analyzed with ECG parameters with and without RV pacing. Results: Mid-RV septal positioning was achieved in all patients. TEE transgastric view (0°-40°/90°-130°) was the optimal view for visualizing device position. Mean tricuspid valve-LP distance was 4.9 ± 0.9 cm, mean pulmonary valve-LP distance was 4.2 ± 1 cm, and calculated RV apex-LP distance was 2.9 ± 1 cm. Mean LP paced QRS width was 160.8 ± 28 ms and increased from 117.2 ± 34 ms at baseline. LP RV pacing resulted in left bundle branch block pattern on ECG and 37.8% QRS widening by 43.5 ± 29 ms. Conclusion: TEE may guide LP implantation in the nonapical mid-RV position. Further studies are required to establish whether this technique reduces implant complications compared with conventional fluoroscopy.

Incidence and implications of atrial fibrillation in patients hospitalized for COVID compared to non-COVID pneumonia: A multicenter cohort study.

Background: Atrial fibrillation (AF) has been reported to occur with coronavirus disease 2019 (COVID-19), but whether it is related to myocarditis or lung injury is unclear. Objectives: The purpose of this study was to compare incident AF in patients with pneumonia/adult respiratory distress syndrome (ARDS) with and without COVID. Methods: This retrospective multicenter cohort study from 17 hospitals (March 2020 to December 2021) utilizing the University of California COVID Research Data Set (CORDS) included patients aged ≥18 years with primary diagnosis of pneumonia or ARDS during hospitalization. Patients with a history of AF were excluded. All subjects had documented COVID test results. Cohorts were compared using the χ2 test for categorical variables and the Wilcoxon rank test for continuous variables. Multivariable logistic regression models were used to investigate the association between COVID and development of new AF. Results: Of the 39,415 subjects, 12.2% had COVID. The COVID+ cohort consisted predominantly of younger males with more comorbidities. Incident AF was lower in the COVID+ group than in the non-COVID group (523 [10.85%] vs 4899 [14.16%]; odds ratio [OR] 0.74; P <.001), which remained significant after adjustment for demographics and comorbidities (OR 0.71; P <.001). Patients had normal cardiac troponin levels. AF was related to intensive care unit care, pressor support, and mechanical ventilation, and was associated with higher mortality (26.2% vs 10.21%; P <.001) and longer hospitalization (22.5 vs 15.1 days; P <.001) in the COVID+ group compared to the controls. Conclusion: Incident AF is lower in COVID+ compared to non-COVID pneumonia/ARDS patients and seems to be related to severity of illness rather cardiac injury. AF was associated with higher mortality and prolonged hospitalization.

Noninvasive Stereotactic Radiation for Refractory Ventricular Tachycardia After Failure of Cardiac Sympathetic Denervation.

Stereotactic body radiation therapy is a novel treatment option for refractory ventricular tachycardia. We present a case of ventricular tachycardia, with epicardial origin located in large inferior infarct scar, that recurred despite treatment with multiple antiarrhythmic drugs, catheter ablation, and cardiac sympathetic denervation. Stereotactic body radiation therapy safely and effectively terminated the arrhythmia. (Level of Difficulty: Advanced.).

Catheter Ablation for Atrial Fibrillation in Adult Congenital Heart Disease: An International Multicenter Registry Study.

BACKGROUND: Data on atrial fibrillation (AF) ablation and outcomes are limited in patients with congenital heart disease (CHD). We aimed to investigate the characteristics of patients with CHD presenting for AF ablation and their outcomes. METHODS: A multicenter, retrospective analysis was performed of patients with CHD undergoing AF ablation between 2004 and 2020 at 13 participating centers. The severity of CHD was classified using 2014 Pediatric and Congenital Electrophysiology Society/Heart Rhythm Society guidelines. Clinical data were collected. One-year complete procedural success was defined as freedom from atrial tachycardia or AF in the absence of antiarrhythmic drugs or including previously failed antiarrhythmic drugs (partial success). RESULTS: Of 240 patients, 127 (53.4%) had persistent AF, 62.5% were male, and mean age was 55.2±13.3 years. CHD complexity categories included 147 (61.3%) simple, 68 (28.3%) intermediate, and 25 (10.4%) severe. The most common CHD type was atrial septal defect (n=78). More complex CHD conditions included transposition of the great arteries (n=14), anomalous pulmonary veins (n=13), tetralogy of Fallot (n=8), cor triatriatum (n=7), single ventricle physiology (n=2), among others. The majority (71.3%) of patients had trialed at least one antiarrhythmic drug. Forty-six patients (22.1%) had reduced systemic ventricular ejection fraction <50%, and mean left atrial diameter was 44.1±8.2 mm. Pulmonary vein isolation was performed in 227 patients (94.6%); additional ablation included left atrial linear ablations (40%), complex fractionated atrial electrogram (19.2%), and cavotricuspid isthmus ablation (40.8%). One-year complete and partial success rates were 45.0% and 20.5%, respectively, with no significant difference in the rate of complete success between complexity groups. Overall, 38 patients (15.8%) required more than one ablation procedure. There were 3 (1.3%) major and 13 (5.4%) minor procedural complications. CONCLUSIONS: AF ablation in CHD was safe and resulted in AF control in a majority of patients, regardless of complexity. Future work should address the most appropriate ablation targets in this challenging population.

Association of advanced age with procedural complications and in-hospital outcomes from left atrial appendage occlusion device implantation in patients with atrial fibrillation: insights from the National Inpatient Sample of 36,065 procedures.

BACKGROUND: Age-stratified analyses of atrial fibrillation (AF) patients undergoing percutaneous left atrial appendage occlusion (LAAO) are limited. The purpose of current study was to compare in-hospital outcomes in elderly AF patients (age > 80 years) to a relatively younger cohort (age £ 80 years) after LAAO. METHODS: Data were extracted from National Inpatient Sample for calendar years 2015-2018. LAAO device implantations were identified on the basis of International Classification of Diseases, 9th and 10th Revision, Clinical Modification codes of 37.90 and 02L73DK. The outcomes assessed in our study included complications, inpatient mortality, and resource utilization with LAAO. RESULTS: A total of 36,065 LAAO recipients were included in the final analysis, of which 34.6% (n=12,475) were performed on elderly AF patients. Elderly AF patients had a higher prevalence of major complications (6.7% vs. 5.7%, p < 0.01) and mortality (0.4% vs. 0.1%, p < 0.01) after LAAO device implantation in the crude analysis. After multivariate adjustment of potential confounders, age > 80 years was associated with increased risk of inpatient mortality (adjusted odds ratio [aOR] 4.439, 95% confidence interval [CI] 2.391-8.239) but not major complications (aOR 1.084, 95% CI 0.971-1.211), prolonged length of stay (aOR 0.943, 95% CI 0.88-1.101), or increased hospitalization costs (aOR 0.909, 95% CI 0.865-0.955). CONCLUSION: Over 1 in 3 LAAO device implantations occurred in elderly AF patients. After adjusting for potential confounding variables, advanced age was associated with inpatient mortality, but not with other LAAO procedural-related outcomes including major complications, prolonged length of stay, or increased hospitalization costs.

Association of heart failure with procedural complications and in-hospital outcomes from left atrial appendage occlusion device implantation in patients with atrial fibrillation: insights from the national inpatient sample of 62 980 procedures.

AIMS: To determine outcomes in atrial fibrillation (AF) patients undergoing percutaneous left atrial appendage occlusion (LAAO) with concomitant heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF). METHODS AND RESULTS: Data were extracted from National Inpatient Sample for calendar years 2015-2019. LAAO device implantations were identified on the basis of ICD-10-CM code of 02L73DK. The outcomes assessed in our study included complications, in-patient mortality, and resource utilization. A total of 62 980 LAAO device implantations were studied. HFpEF (14.4%, n = 9040) and HFrEF (11.2%, n = 7100) were associated with a higher prevalence of major complications and in-patient mortality in crude analysis. In the multivariate model adjusted for potential confounders, HFpEF and HFrEF were not associated with major complications [adjusted odds ratio (aOR) 1.04, 95% confidence interval (CI) 0.93-1.16 and aOR 1.07, 95% CI 0.95-1.21] or in-patient mortality (aOR 1.48, 95% CI 0.85-2.55 and aOR 1.26, 95% CI 0.67-2.38). HFpEF and HFrEF were associated with prolonged length of stay (LOS) > 1 day (aOR 1.41, 95% CI 1.31-1.53 and aOR 1.66, 95% CI 1.53-1.80) and increased hospitalization costs > median cost 24 752$ (aOR 1.26, 95% CI 1.19-1.34 and aOR 1.21, 95% CI 1.13-1.29). CONCLUSION: The prevalence of HF in AF patients undergoing percutaneous LAAO was approximately 26%. HF was not independently associated with major complications and in-patient mortality but was associated with prolonged LOS and higher hospitalization costs.

Effects of Supervised Exercise Training on Atrial Fibrillation: A META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS.

PURPOSE: Atrial fibrillation (AF) is associated with the comorbidities of a sedentary lifestyle. Endurance athletes also show an increased incidence of AF. The role of exercise in the treatment of AF is unknown so this study aimed to examine the effects of supervised exercise on AF. METHODS: A meta-analysis of randomized controlled trials (RCTs) examining supervised exercise training in participants with AF was performed. The primary outcome was AF recurrence and burden. Secondary outcomes included AF symptoms, quality of life, and cardiorespiratory fitness (CRF). RESULTS: Thirteen RCTs, involving 1155 participants, were included. Paroxysmal AF was present in 34% and persistent AF in 64%. The types of exercise were diverse and included cardiac rehabilitation (64%), aerobic training (7%), Qi Gong (4%), interval training (11%), and yoga (15%). Exercise training reduced AF recurrence (relative risk = 0.77: 95% CI, 0.60-0.99), improved quality of life in 5 of the 10 components of the Short Form 36 survey, and improved CRF (standardized mean difference [SMD] = 0.56: 95% CI, 0.27-0.85). The AF burden was reduced only in studies that included continuous ambulatory monitoring (SMD =-0.49: 95% CI, -0.96 to -0.01) but not when all studies were included (SMD =-0.12: 95% CI, -0.61 to 0.38). There was no difference in adverse events between exercise and control. CONCLUSIONS: Supervised exercise training is safe, reduces AF recurrence, and improves quality of life and CRF in participants with AF. Further large RCTs with ambulatory monitoring and robust exercise regimens are needed to assess the effects of exercise training on AF burden and AF symptoms.

Advancing global equity in cardiac care as cardiac implantable electronic device reuse comes of age.

A nation's health and economic development are inextricably and synergistically connected. Stark differences exist between wealthy and developing nations in the use of cardiac implantable electronic devices (CIEDs). Cardiovascular disease is now the leading cause of death in low- and middle-income countries (LMIC), with a significant burden from rhythm-related diseases. As science, technology, education, and regulatory frameworks have improved, CIED recycling for exportation and reuse in LMIC has become possible and primed for widespread adoption. In our manuscript, we outline the science and regulatory pathways regarding CIED reuse. We propose a pathway to advance this technology that includes creating a task force to establish standards for CIED reuse, leveraging professional organizations in areas of need to foster the professional skills for CIED reuse, collaborating with regulatory agencies to create more efficient regulatory expectations and bring the concept to scale, and establishing a global CIED reuse registry for quality assurance and future science.

Electrical abnormalities with St. Jude/Abbott pacing leads: A systematic review and meta-analysis.

BACKGROUND: Although there is a paucity of contemporary data on pacemaker lead survival rates, small studies suggest that some leads may have higher malfunction rates than do others. OBJECTIVE: The purpose of this study was to determine the malfunction rates of current pacemaker leads. METHODS: A meta-analysis including studies that examined the non-implant-related lead malfunction rates of current commercially available active fixation pacemaker leads was performed. An electronic search of MEDLINE/PubMed, Scopus, and Embase was performed. DerSimonian and Laird random effects models were used. RESULTS: Eight studies with a total of 14,579 leads were included. Abbott accounted for 10,838 (74%), Medtronic 2510 (17%), Boston Scientific 849 (6%), and MicroPort 382 (3%) leads. The weighted mean follow-up period was 3.6 years. Lead abnormalities occurred in 5.0% of all leads, 6.1% of Abbott leads, 1.1% of Medtronic, 1.4% of Boston Scientific, and 5.5% of MicroPort. The most common lead abnormality was lead noise with normal impedance. Abbott leads were associated with an increased risk of abnormalities (relative risk [RR] 7.81; 95% confidence interval [CI] 3.21-19.04), reprogramming (RR 7.95; 95% CI 3.55-17.82), and lead revision or extraction (RR 8.91; 95% CI 3.36-23.60). Abbott leads connected to an Abbott generator had the highest abnormality rate (8.0%) followed by Abbott leads connected to a non-Abbott generator (4.7%) and non-Abbott leads connected to an Abbott generator (0.4%). CONCLUSIONS: Abbott leads are associated with an increased risk of abnormalities compared with leads of other manufacturers, primarily manifesting as lead noise with normal impedance, and are associated with an increased risk of lead reprogramming and lead revision or extraction.

Sex-Specific Classification of Drug-Induced Torsade de Pointes Susceptibility Using Cardiac Simulations and Machine Learning.

Torsade de Pointes (TdP), a rare but lethal ventricular arrhythmia, is a toxic side effect of many drugs. To assess TdP risk, safety regulatory guidelines require quantification of hERG channel block in vitro and QT interval prolongation in vivo for all new therapeutic compounds. Unfortunately, these have proven to be poor predictors of torsadogenic risk, and are likely to have prevented safe compounds from reaching clinical phases. Although this has stimulated numerous efforts to define new paradigms for cardiac safety, none of the recently developed strategies accounts for patient conditions. In particular, despite being a well-established independent risk factor for TdP, female sex is vastly under-represented in both basic research and clinical studies, and thus current TdP metrics are likely biased toward the male sex. Here, we apply statistical learning to synthetic data, generated by simulating drug effects on cardiac myocyte models capturing male and female electrophysiology, to develop new sex-specific classification frameworks for TdP risk. We show that (i) TdP classifiers require different features in females vs. males; (ii) male-based classifiers perform more poorly when applied to female data; and (iii) female-based classifier performance is largely unaffected by acute effects of hormones (i.e., during various phases of the menstrual cycle). Notably, when predicting TdP risk of intermediate drugs on female simulated data, male-biased predictive models consistently underestimate TdP risk in women. Therefore, we conclude that pipelines for preclinical cardiotoxicity risk assessment should consider sex as a key variable to avoid potentially life-threatening consequences for the female population.