Three-year incidence of pacemaker implantation in patients with atrial fibrillation and sinus node dysfunction receiving ablation versus antiarrhythmic drugs

BACKGROUND

Sinus node dysfunction (SND) is commonly seen in patients with atrial fibrillation (AF). The purpose of this study was to compare the incidence of pacemaker implantation among patients with SND and AF treated with catheter ablation (CA) versus anti-arrhythmic drugs (AADs).

METHODS

The 2013-2022 Optum Clinformatics database, an administrative claims database for commercially insured individuals in the United States (US), was used for this study. Patients with AF and SND and a history of at least one AAD prescription were identified and classified into CA or AAD cohorts based on subsequent treatment received. Inverse probability treatment weighting was applied to balance socio-demographic and clinical characteristics between the cohorts. Weighted Cox regression modeling was used to evaluate the differential risk of incident permanent pacemaker (PPM) implantation. Sub-analyses were performed by AF type (paroxysmal versus persistent).

RESULTS

A total of 1206 patients in the AAD cohort and 1624 patients in the CA cohort were included. Study cohorts were well-balanced post-weighting. The incidence rate of PPM implantation (per 1000 person-year) was 55.8 for the CA cohort and 117.8 for the AAD cohort. Regression analysis demonstrated that the CA cohort had 42% lower risk of incident PPM implantation than those treated with AADs (hazard ratio [HR], 0.58; 95% CI, 0.46-0.72, p < 0.001). CA-treated patients had lower risks of PPM implantation versus AAD-treated patients among those with paroxysmal AF (HR, 0.48; 95% CI, 0.34-0.69, p < 0.001) and persistent AF (HR, 0.57; 95% CI, 0.40-0.81, p = 0.002).

CONCLUSIONS

Patients with AF and SND treated with CA have significantly lower risks of incident PPM implantation compared with those treated with an AAD.

The role of comorbidities, medications, and social determinants of health in understanding urban-rural outcome differences among patients with heart failure

PURPOSE

There is now a 20% disparity in all-cause, excess deaths between urban and rural areas, much of which is driven by disparities in cardiovascular death. We sought to explain the sources of these disparities for Medicare beneficiaries with heart failure with reduced ejection fraction (HFrEF).

METHODS

Using a sample of Medicare Parts A, B, and D, we created a cohort of 389,528 fee-for-service beneficiaries with at least 1 heart failure hospitalization from 2008 to 2017. The primary outcome was 30-day mortality after discharge; 1-year mortality, readmissions, and return emergency room (ER) admissions were secondary outcomes. We used hierarchical, logistic regression modeling to determine the contribution of comorbidities, guideline-directed medical therapy (GDMT), and social determinants of health (SDOH) to outcomes.

RESULTS

Thirty-day mortality rates after hospital discharge were 6.3% in rural areas compared to 5.7% in urban regions (P < .001); after adjusting for patient health and GDMT receipt, the 30-day mortality odds ratio for rural residence was 1.201 (95% CI 1.164-1.239). Adding the SDOH measure reduced the odds ratio somewhat (1.140, 95% CI 1.103-1.178) but a gap remained. Readmission rates in rural areas were consistently lower for all model specifications, while ER admissions were consistently higher.

CONCLUSIONS

Among patients with HFrEF, living in a rural area is associated with an increased risk of death and return ER visits within 30 days of discharge from HF hospitalization. Differences in SDOH appear to partially explain mortality differences but the remaining gap may be the consequence of rural-urban differences in HF treatment.

IV Diuresis in Alternative Treatment Settings for the Management of Heart Failure: Implications for Mortality, Hospitalizations and Cost

BACKGROUND

Recent advances in heart failure (HF) care have sought to shift management from inpatient to outpatient and observation settings. We evaluated the association among HF treatment in the (1) inpatient; (2) observation; (3) emergency department (ED); and (4) outpatient settings with 30-day mortality, hospitalizations and cost.

METHODS

Using 100% Medicare inpatient, outpatient and Part B files from 2011-2018, 1,534,708 unique patient encounters in which intravenous (IV) diuretics were received for a primary diagnosis of HF were identified. Encounters were sorted into mutually exclusive settings: (1) inpatient; (2) observation; (3) ED; or (4) outpatient IV diuretic clinic. The primary outcome was 30-day all-cause mortality. Secondary outcomes included 30-day hospitalization and total 30-day costs. Multivariable logistic and linear regression were used to examine the association between treatment location and the primary and secondary outcomes.

RESULTS

Patients treated in observation and outpatient settings had lower 30-day mortality rates (observation OR 0.67, 95% CI 0.66-0.69; P < 0.001; outpatient OR 0.53, 95% CI 0.51-0.55; P < 0.001) compared to those treated in inpatient settings. Observation and outpatient treatment were also associated with decreased 30-day total cost compared to inpatient treatment. Observation relative cost -$5528.77, 95% CI -$5613.63 to -$5443.92; outpatient relative cost -$7005.95; 95% CI -$7103.94 to -$6907.96). Patients treated in the emergency department and discharged had increased mortality rates (OR 1.15, 95% CI 1.13-1.17; P < 0.001) and increased rates of hospitalization (OR 1.72, 95% CI 1.70-1.73; P < 0.001) compared to patients treated as inpatients.

CONCLUSIONS

Medicare beneficiaries who received IV diuresis for acute HF in the outpatient and observation settings had lower mortality rates and decreased costs of care compared to patients treated as inpatients. Outpatient and observation management of acute decompensated HF, when available, is a safe and cost-effective strategy in certain populations of patients with HF.

Benefit of cardiac resynchronization therapy among older patients: A patient-level meta-analysis

BACKGROUND

Cardiac resynchronization therapy (CRT) reduces heart failure hospitalizations (HFH) and mortality for guideline-indicated patients with heart failure (HF). Most patients with HF are aged ≥70 years but such patients are often under-represented in randomized trials.

METHODS

Patient-level data were combined from 8 randomized trials published 2002-2013 comparing CRT to no CRT (n = 6,369). The effect of CRT was estimated using an adjusted Bayesian survival model. Using age as a categorical (<70 vs ≥70 years) or continuous variable, the interaction between age and CRT on the composite end point of HFH or all-cause mortality or all-cause mortality alone was assessed.

RESULTS

The median age was 67 years with 2436 (38%) being 70+; 1,554 (24%) were women; 2,586 (41%) had nonischemic cardiomyopathy and median QRS duration was 160 ms. Overall, CRT was associated with a delay in time to the composite end point (adjusted hazard ratio [aHR] 0.75, 95% credible interval [CI] 0.66-0.85, P = .002) and all-cause mortality alone (aHR of 0.80, 95% CI 0.69-0.96, P = .017). When age was treated as a categorical variable, there was no interaction between age and the effect of CRT for either end point (P > .1). When age was treated as a continuous variable, older patients appeared to obtain greater benefit with CRT for the composite end point (P for interaction = .027) with a similar but nonsignificant trend for mortality (P for interaction = .35).

CONCLUSION

Reductions in HFH and mortality with CRT are as great or greater in appropriately indicated older patients. Age should not be a limiting factor for the provision of CRT.

Neurologic impact of atrial fibrillation

PURPOSE OF REVIEW

Cognitive dysfunction is a complex condition that is becoming increasingly more prevalent. There has been growing acknowledgement that individuals with atrial fibrillation are at an increased risk of cognitive dysfunction beyond the association of age with both disorders. The purpose of this review is to explore the potential underlying mechanisms connecting atrial fibrillation and cognitive dysfunction and to examine the existing evidence for potential treatment options.

RECENT FINDINGS

Many mechanisms have been proposed for the association between cognitive dysfunction and atrial fibrillation. These include cerebral infarction (both micro and macro embolic events), cerebral microbleeds including those secondary to therapeutic anticoagulation, an increased inflammatory state, cerebral hypoperfusion, and a genetic predisposition to both diseases. Treatments designed to target each of these mechanisms have led to mixed results and there are no specific interventions that have definitively led to a reduction in the incidence of cognitive dysfunction.

SUMMARY

The relationship between cognitive dysfunction and atrial fibrillation remains poorly understood. Standard of care currently focuses on reducing risk factors, managing stroke risk, and maintaining sinus rhythm in appropriately selected patients. Further work needs to be conducted in this area to limit the progression of cognitive dysfunction in patients with atrial fibrillation.

Developing, optimizing, and evaluating patient infographics for diagnosing cardiac amyloidosis

Objective

Advancements in diagnostics and treatment options for cardiac amyloidosis have improved patient outcomes, yet few patient education materials exist to help patients understand the disease and diagnosis process. We sought to develop and evaluate a set of plain language, patient-centered infographics describing the condition and common diagnostic tests.

Methods

Using health literacy best practices, we developed 7 infographics which were further revised based on multilevel stakeholder feedback. To evaluate the materials, we recruited 100 patients from healthcare settings in Chicago, IL; participants completed a web-assisted interview during which they were randomized 1:1 to first view either our infographics or a standard material. Participants completed a knowledge assessment on their assigned material and subsequently reported impressions of both materials.

Results

No differences were found between study arms in knowledge. The infographics took significantly less time to read and were more highly rated by participants in terms of appearance and understandability. Over two-thirds of participants preferred the infographics to the standard.

Conclusions

The infographics created may improve the learning process about a complex condition and diagnosis process unknown to most adults.

Innovation

These infographics are the first of their kind for cardiac amyloidosis and were created using health literacy best practices.

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.

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.

Early mortality after inpatient versus outpatient catheter ablation in patients with atrial fibrillation

BACKGROUND

Rates of early mortality and complications after catheter ablation (CA) of atrial fibrillation (AF) vary across health care settings.

OBJECTIVE

The purpose of this study was to identify the rate and predictors of early mortality (within 30 days) after CA in the inpatient and outpatient settings.

METHODS

Using the Medicare Fee for Service database, we analyzed 122,289 patients who underwent CA for treatment of AF between 2016 and 2019 to define 30-day mortality in both inpatients and outpatients. Odds of adjusted mortality were assessed with several methods, including inverse probability of treatment weighting.

RESULTS

Mean age was 71.9 ± 6.7 years, 44% were women, and mean CHA2DS2-VASc score was 3.2 ± 1.7. Overall, 82% underwent AF ablation as an outpatient. Mortality rate 30 days after CA was 0.6%, with inpatients accounting for 71.5% of deaths (P <.001). Early mortality rates were 0.2% for outpatient procedures and 2.4% for inpatient procedures. The prevalence of comorbidities was significantly higher in patients with early mortality. Patients with early mortality had significantly higher rates of postprocedural complications. After adjustment, inpatient ablation was significantly associated with early mortality (adjusted odds ratio [aOR] 3.81; 95% confidence interval [CI] 2.87-5.08; P <.001). Hospitals with high overall ablation volume had 31% lower odds of early mortality (highest vs lowest tertile: aOR 0.69; 95% CI 0.56-0.86; P <.001).

CONCLUSION

AF ablation conducted in the inpatient setting is associated with a higher rate of early mortality compared with outpatient AF ablation. Comorbidities are associated with enhanced risk of early mortality. High overall ablation volume is associated with a lower risk of early mortality.

Arrhythmias After Acute Myocardial Infarction

The incidence of arrhythmia after myocardial infarction has declined since the introduction of reperfusion techniques. Nevertheless, ischemic arrhythmias are often associated with increased morbidity and mortality particularly in the first 48 hours after hospital admission. This paper presents a comprehensive review of the epidemiology, characteristics, and management of ischemic tachy- and brady-arrhythmias focusing on the period shortly after myocardial infarction (MI) in patients with both ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI).

Sex-based differences in atrial fibrillation ablation adverse events

OBJECTIVE

Older, relatively small studies identified female sex as a risk factor for adverse events after catheter ablation for atrial fibrillation (AF). We aimed to assess contemporary sex-based differences in baseline and procedural characteristics, adverse events, and quality of life among adults undergoing catheter ablation for AF.

METHODS

In this observational cohort study, we evaluated those enrolled in the National Cardiovascular Data Registry AFib Ablation Registry between January 2016 and September 2020. Using logistic regression, we analysed the association between patient sex and in-hospital adverse events.

RESULTS

Among 58 960 adults (34.6% women) from 150 centres undergoing AF ablation by 706 physicians, women were older (68 vs 64 years, p<0.001), had more comorbidities, and had lower AF-related quality of life at the time of ablation (mean Atrial Fibrillation Effect on QualiTy-of-life Questionnaire) score: 51.8 vs 62.2, p<0.001). Women had a higher risk of hospitalisation >1 day (adjusted OR (aOR) 1.41 (95% CI 1.33 to 1.49)), major adverse event (aOR 1.60 (95% CI 1.33 to 1.92)) and any adverse event (aOR 1.57 (95% CI 1.41 to 1.75)). Women had a higher risk of bradycardia requiring pacemaker, phrenic nerve damage, pericardial effusion, bleeding and vascular injury, but had no differences in death or acute pulmonary vein isolation.

CONCLUSIONS

Among almost 60 000 patients in the largest prospective registry of AF ablation procedures, female sex was independently associated with a higher risk of hospitalisation >1 day, adverse events, and reduced quality of life, although there were no differences in death or acute pulmonary vein isolation.

Contemporary trends in cardiac electrophysiology procedures in the United States, and impact of a global pandemic

Background

There are limited data on trends in nationwide cardiac electrophysiology (EP) procedures in the United States before and during the global COVID-19 pandemic.

Objective

We aimed to understand contemporary EP procedural trends and how the COVID-19 pandemic impacted them.

Methods

Trends were obtained from publicly reported Centers for Medicare and Medicaid Services data from 2013 to 2020 (latest available). Rates of catheter-based EP procedures (EP studies and ablations) and cardiac implantable electronic device (CIED) procedures were analyzed. All procedural rates were calculated per 100,000 Medicare beneficiaries (year specific). Procedure physician subspecialty was also reported.

Results

From 2013 to 2019, annual rate of all cardiac EP procedures increased from 817.91 to 1089.68 per 100,000 beneficiaries. Catheter-based EP procedures increased from 323.73 to 675.01, while CIED rates decreased from 494.18 to 414.67. While all ablation procedures increased over time, relative proportion of ablation procedures being pulmonary vein isolation (PVI) increased (9.9% of ablations in 2013, to 18.2% in 2019). In 2020, rates of both catheter-based EP procedures and CIED procedures decreased; however, PVI share of ablation continued to increase in 2020 comprising 25.2% of ablation procedures.

Conclusion

Rates of EP procedures have increased among Medicare beneficiaries, with catheter-based procedures now eclipsing CIEDs. Additionally, a greater proportion of catheter-based EP procedures are PVI, but they still represent a minority of all ablations. In 2020, rates of EP procedures were attenuated, yet the proportion of PVI ablations increased to over one-fourth of ablation procedures. These data have important implications for the EP workforce.

Comparative Effectiveness of Left Atrial Appendage Occlusion Versus Oral Anticoagulation by Sex

BACKGROUND

The comparative real-world outcomes of older patients with atrial fibrillation (AF) treated with anticoagulation compared with left atrial appendage occlusion (LAAO) may be different from those in clinical trials because of differences in anticoagulation strategies and patient demographics, including a greater proportion of women. We sought to compare real-world outcomes between older patients with AF treated with anticoagulation and those treated with LAAO by sex.

METHODS

Using Medicare claims data from 2015 to 2019, we identified LAAO-eligible beneficiaries and divided them into sex subgroups. Patients receiving LAAO were matched 1:1 to those receiving anticoagulation alone through propensity score matching. The risks of mortality, stroke or systemic embolism, and bleeding were compared between matched groups with adjustment for potential confounding characteristics in Cox proportional hazards models.

RESULTS

Among women, 4085 LAAO recipients were matched 1:1 to those receiving anticoagulation; among men, 5378 LAAO recipients were similarly matched. LAAO was associated with a significant reduction in the risk of mortality for women and men (hazard ratio [HR], 0.509 [95% CI, 0.447-0.580]; and HR, 0.541 [95% CI, 0.487-0.601], respectively; P<0.0001), with a similar finding for stroke or systemic embolism (HR, 0.655 [95% CI, 0.555-0.772]; and HR, 0.649 [95% CI, 0.552-0.762], respectively; P<0.0001). Bleeding risk was significantly greater in LAAO recipients early after implantation but lower after the 6-week periprocedural period for women and men (HR, 0.772 [95% CI, 0.676-0.882]; and HR, 0.881 [95% CI, 0.784-0.989], respectively; P<0.05).

CONCLUSIONS

In a real-world population of older Medicare beneficiaries with AF, compared with anticoagulation, LAAO was associated with a reduction in the risk of death, stroke, and long-term bleeding among women and men. These findings should be incorporated into shared decision-making with patients considering strategies for reduction in AF-related stroke.

Effects of Ablation Versus Drug Therapy on Quality of Life by Sex in Atrial Fibrillation: Results From the CABANA Trial

Background Women with atrial fibrillation (AF) demonstrate more AF-related symptoms and worse quality of life (QOL). Whether increased use of ablation in women reduces sex-related QOL differences is unknown. Sex-related outcomes for ablation versus drug therapy was a prespecified analysis in the CABANA (Catheter Ablation Versus Antiarrhythmic Drug Therapy for Atrial Fibrillation) trial. Methods and Results Symptoms were assessed periodically over 60 months with the Mayo AF-Specific Symptom Inventory (MAFSI) frequency score, and QOL was assessed with the Atrial Fibrillation Effect on Quality of Life (AFEQT) summary and component scores. Women had lower baseline QOL scores than men (mean AFEQT scores 55.9 and 65.6, respectively). Ablation patients improved more than drug therapy patients with similar treatment effect by sex: AFEQT 12-month mean adjusted treatment difference in women 6.1 points (95% CI, 3.5-8.6) and men 4.9 points (95% CI, 3.0-6.9). Participants with baseline AFEQT summary scores <70 had greater QOL improvement, with a mean treatment difference at 12 months of 7.6 points for women (95% CI, 4.3-10.9) and 6.4 points for men (95% CI, 3.3-9.4). The mean adjusted difference in MAFSI frequency score between women randomized to ablation versus drug therapy at 12 months was -2.5 (95% CI, -3.4 to -1.6); for men, the difference was -1.3 (95% CI, -2.0 to -0.6). Conclusions Compared with drug therapy for AF, ablation resulted in more QOL improvement in both sexes, primarily driven by improvements in those with lower baseline QOL. Ablation did not eliminate the AF-related QOL gap between women and men. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT00911508.

Comparative risk of dementia among patients with atrial fibrillation treated with catheter ablation versus anti-arrhythmic drugs

Atrial fibrillation (AF) is associated with an increased risk of dementia. Emerging evidence suggests AF suppression is associated with reduced risk of dementia, but the optimal strategy to achieve this is unknown. We sought to compare the risk of dementia in patients with AF who underwent catheter ablation (CA) versus anti-arrhythmic drug (AAD) treatment. METHODS AND RESULTS: Using the 2000 to 2021 Optum Clinformatics database, patients with AF who underwent CA versus AAD treatment (≥1 prescription fill for ≥2 different AADs) were identified and propensity score matched overall and within sex subgroups. A cause-specific hazard model was performed to assess dementia overall and in sex-specific subgroups. After matching, there were 19,088 patients per group. CA was associated with a 41% lower risk of dementia compared with AAD alone (1.9% vs 3.3%; hazard ratio [HR] 0.59, 95% confidence interval [CI] 0.52-0.67, log-rank P < .0001). When examined by sex, dementia risk reduction associated with CA versus AAD use alone was observed among both males (HR 0.55, 95% CI 0.46-0.66) and females (HR 0.60, 95% CI 0.50-0.72). Though not studied as a primary outcome, patients treated with CA were also observed to have 49% lower associated risk of mortality compared with AAD only (HR 0.51 95% CI 0.46-0.55, P < .0001). CONCLUSIONS: Among patients treated for AF, CA was associated with significantly lower risk of dementia and death compared with AADs only. These reductions in risk associated with CA versus AAD were seen in both males and females.

Racial and ethnic differences in implantable cardioverter-defibrillator patient selection, management, and outcomes

Racial and ethnic differences in treatment-cardiovascular and otherwise-have been documented in many aspects of the American health care system and can be seen in implantable cardioverter-defibrillator (ICD) patient selection, counseling, and management. ICDs have been demonstrated to be a powerful tool in the prevention of sudden cardiac death, yet uptake across all eligible patients has been modest. Although patients who do not identify as White are disproportionately eligible for ICDs in the United States, they are less likely to see specialists, be counseled on ICDs, and ultimately have an ICD implanted. This review explores racial and ethnic differences demonstrated in ICD patient selection, outcomes including shock effectiveness, and postimplantation monitoring for both primary and secondary prevention devices. It also highlights barriers for uptake at the health system, physician, and patient levels and suggests areas of further research needed to clarify the differences, illuminate the driving forces of these differences, and investigate strategies to address them.

Advances in Cardiac Electrophysiology

Despite the global COVID-19 pandemic, during the past 2 years, there have been numerous advances in our understanding of arrhythmia mechanisms and diagnosis and in new therapies. We increased our understanding of risk factors and mechanisms of atrial arrhythmias, the prediction of atrial arrhythmias, response to treatment, and outcomes using machine learning and artificial intelligence. There have been new technologies and techniques for atrial fibrillation ablation, including pulsed field ablation. There have been new randomized trials in atrial fibrillation ablation, giving insight about rhythm control, and long-term outcomes. There have been advances in our understanding of treatment of inherited disorders such as catecholaminergic polymorphic ventricular tachycardia. We have gained new insights into the recurrence of ventricular arrhythmias in the setting of various conditions such as myocarditis and inherited cardiomyopathic disorders. Novel computational approaches may help predict occurrence of ventricular arrhythmias and localize arrhythmias to guide ablation. There are further advances in our understanding of noninvasive radiotherapy. We have increased our understanding of the role of His bundle pacing and left bundle branch area pacing to maintain synchronous ventricular activation. There have also been significant advances in the defibrillators, cardiac resynchronization therapy, remote monitoring, and infection prevention. There have been advances in our understanding of the pathways and mechanisms involved in atrial and ventricular arrhythmogenesis.

Coverage with evidence development: where are we now?

OBJECTIVES

CMS' coverage with evidence development (CED) policy allows Medicare beneficiaries to access promising therapies and services while additional data are collected. CED program characteristics are mostly unreported, and qualities associated with retirement of CED data collection requirements are unknown. We aimed to review and systematically describe CED program history and components and report programmatic elements correlated with retirement of CED data collection requirements, while identifying areas for policy improvement.

STUDY DESIGN

Systematic review.

METHODS

We extracted CED information from the CMS website, ClinicalTrials.gov, PubMed, internet searches, and communication with CMS.

RESULTS

There were 27 CED determinations from 2005 to 2022 in 8 therapeutic areas, with the most for cardiovascular diseases (8/27; 30%). Duration of CED programs (range, 1-16 years) and the number of related registries and clinical trials (range, 0-34) were widely variable. Only 4 CEDs have had data collection requirements with continued National Coverage Determination (NCD); 3 relate to cardiovascular therapies, and all have some public availability of findings resulting from CED-related data collection mechanisms. There were 2 instances of NCD revocation and deferral to local coverage decisions.

CONCLUSIONS

Changes in the CED program through improving program predictability and transparency with regard to outstanding questions, roles of relevant stakeholders, and requirements for reporting and reevaluation would strengthen the program's effectiveness. Ultimately, these improvements would provide incentives for stakeholder participation in data collection to achieve the goal of increasing access to beneficial therapies and improving clinical outcomes.

Subcutaneous and Transvenous ICDs: an Update on Contemporary Questions and Controversies

PURPOSE OF REVIEW

While the subcutaneous (S-) implantable cardioverter-defibrillator (ICDs) is an alternative to the transvenous (TV-) ICD in many patients, optimal use remains unclear. In this review, we summarize recent clinically relevant data on sensing algorithms, inappropriate shocks, defibrillation testing, and battery and electrode failures.

RECENT FINDINGS

Changes in sensing algorithms and S-ICD programming have significantly decreased inappropriate shock rates. Avoiding fat below the S-ICD coil and can is key for reducing the defibrillation threshold. While S-ICD battery and electrode failures have resulted in recalls, system components remain commercially available since failure rates are low and no other similar devices are available. The S-ICD is a good alternative to the TV-ICD for many patients, and particularly in light of recently developed device algorithms and improvements in implant technique. Future research will need to better understand: the impact of S-ICD electrode and battery failures and the potential for integrating leadless pacing into a modular S-ICD platform.

Longitudinal Outcomes of Subcutaneous or Transvenous Implantable Cardioverter-Defibrillators in Older Patients

BACKGROUND

The subcutaneous (S-) implantable cardioverter-defibrillator (ICD) is an alternative to the transvenous (TV-) ICD that is increasingly implanted in younger patients; data on the safety and effectiveness of the S-ICD in older patients are lacking.

OBJECTIVES

The purpose of this study was to compare outcomes among older patients who received an S- or TV-ICD.

METHODS

The authors compared S-ICD and single-chamber TV-ICD implants in Fee-For-Service Medicare beneficiaries using the National Cardiovascular Data Registry ICD Registry. Outcomes were ascertained from Medicare claims data. Cox regression or competing-risk models (with TV-ICD as reference) with overlap weights were used to compare death and nonfatal outcomes (device reoperation, device removal for infection, device reoperation without infection, and cardiovascular admission), respectively. Recurrent all-cause readmissions were compared using Anderson-Gill models.

RESULTS

A total of 16,063 patients were studied (age 72.6 ± 5.9 years, 28.4% women, ejection fraction 28.3 ± 8.9%). Compared with TV-ICD patients (n = 15,072), S-ICD patients (n = 991, 6.2% overall) were more often Black, younger, and dialysis dependent and less likely to have history of atrial fibrillation or flutter. In adjusted analyses, there were no differences between device type and risk of all-cause mortality (HR: 1.020; 95% CI: 0.819-1.270), device reoperation (subdistribution [s] HR: 0.976; 95% CI: 0.645-1.479), device removal for infection (sHR: 0.614; 95% CI: 0.138-2.736), device reoperation without infection (sHR: 0.975; 95% CI: 0.632-1.506), cardiovascular readmission (sHR: 1.087; 95% CI: 0.912-1.295), or recurrent all-cause readmission (HR: 1.072; 95% CI: 0.990-1.161).

CONCLUSIONS

In a large representative national cohort of older patients undergoing ICD implantation, risk of death, device reoperation, device removal for infection, device reoperation without infection, and cardiovascular and all-cause readmission were similar among S- and TV-ICD recipients.

Healthcare resource utilization in patients with newly diagnosed atrial fibrillation in the United States

OBJECTIVES

To summarize healthcare resource utilization (HCRU) in patients with newly diagnosed (incident) paroxysmal or persistent atrial fibrillation (AF).

METHODS

This retrospective, observational cohort study assessed HCRU among patients with incident paroxysmal or persistent AF using data from 1 January 2015 to 30 September 2019 in the IBM MarketScan® Research Databases.

RESULTS

A total of 50,796 patients were identified in the overall incident AF cohort. Rates of all-cause inpatient hospital stays, all-cause emergency room visits, and all-cause outpatient visits in the overall incident cohort were 46.8, 114.7, and 2,752.7 events per 100 patient-years (PY), respectively. Rates of cardiovascular-related inpatient stays for the overall population were 11.3 events per 100 PY. During follow-up, 50.4% of the overall cohort filled prescriptions for direct-acting oral anticoagulants and 5.0% had catheter ablation.

CONCLUSIONS

Advances in anticoagulation and ablation have been realized since previously published HCRU analyses of patients with atrial fibrillation. This update suggests that HCRU among patients with incident AF in the US remains high with some subgroups of patients receiving more specialized care.

Complications and Mortality Following CRT-D Versus ICD Implants in Older Medicare Beneficiaries With Heart Failure

OBJECTIVES

This study sought to assess the comparative effectiveness of cardiac resynchronization therapy with defibrillator (CRT-D) over implantable cardioverter-defibrillator (ICD) alone in older Medicare patients with heart failure with reduced ejection fraction (HFrEF).

BACKGROUND

Despite growing numbers of older patients with HFrEF, the benefits of cardiac resynchronization therapy (CRT) in this group are largely unknown.

METHODS

A cohort of fee-for-service Medicare beneficiaries ≥65 years of age with HFrEF and enrolled in Medicare Part D who underwent CRT-D or ICD implantation from January 2008 to August 2015 was identified. Beneficiaries were divided by age (65-74, 75-84, and 85+ years), and outcomes were compared between the CRT-D and ICD groups after inverse probability weighting.

RESULTS

Compared with the ICD group, the CRT-D group was older and more likely to be White, be female, and have left bundle branch block. After weighting, overall complications were high across age and device groups (14%-20%). The 1-year mortality was high across all groups. In the 2 oldest age strata, the hazard of death was lower in the CRT-D group (HR: 0.90; 95% CI: 0.86-0.95 and HR: 0.81; 95% CI: 0.72-0.90, respectively; P < 0.001); the hazard of heart failure hospitalization was lower for CRT-D vs ICD in the 85+ years age group (HR: 0.82; 95% CI: 0.74-0.92; P < 0.001).

CONCLUSIONS

In older Medicare beneficiaries undergoing ICD with or without CRT, complications and 1-year mortality were high. Compared with ICD alone, CRT-D was associated with a lower hazard of mortality in patients ≥74 years of age and lower hazard of HF hospitalization in those ≥85 years of age. These findings support the use of CRT in eligible older patients undergoing ICD implantation.

Strategies to Reduce Low-Value Cardiovascular Care: A Scientific Statement From the American Heart Association

Low-value health care services that provide little or no benefit to patients are common, potentially harmful, and costly. Nearly half of the patients in the United States will receive at least 1 low-value test or procedure annually, creating risk of avoidable complications from subsequent cascades of care and excess costs to patients and society. Reducing low-value care is of particular importance to cardiovascular health given the high prevalence and costs of cardiovascular disease in the United States. This scientific statement describes the current scope and impact of low-value cardiovascular care; reviews existing literature on patient-, clinician-, health system-, payer-, and policy-level interventions to reduce low-value care; proposes solutions to achieve meaningful and equitable reductions in low-value care; and suggests areas for future research priorities.

Arrhythmias in Female Patients: Incidence, Presentation and Management

There is a growing appreciation for differences in epidemiology, treatment, and outcomes of cardiovascular conditions by sex. Historically, cardiovascular clinical trials have under-represented females, but findings have nonetheless been applied to clinical care in a sex-agnostic manner. Thus, much of the collective knowledge about sex-specific cardiovascular outcomes result from post hoc and secondary analyses. In some cases, these investigations have revealed important sex-based differences with implications for optimizing care for female patients with arrhythmias. This review explores the available evidence related to cardiac arrhythmia care among females, with emphasis on areas in which important sex differences are known or suggested. Considerations related to improving female enrollment in clinical trials as a way to establish more robust clinical evidence for the treatment of females are discussed. Areas of remaining evidence gaps are provided, and recommendations for areas of future research and specific action items are suggested. The overarching goal is to improve appreciation for sex-based differences in cardiac arrhythmia care as 1 component of a comprehensive plan to optimize arrhythmia care for all patients.

Leadless Pacemaker Implantation Complications and the Denominator Problem

In the accompanying article, Hauser and colleagues relay further analysis of complications associated with Medtronic Micra® Leadless pacemaker implantation procedures in global clinical practice.¹ The basis of the analyses is principally the Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) Database, but it also includes reports to other FDA databases. The analysis builds on a prior report of safety events related to the Micra® leadless pacing device this time with more than 50% more events.² This article is protected by copyright. All rights reserved.

Women in Procedural Leadership Roles in Cardiology: The Women In Local Leadership (WILL) Observational Study

BACKGROUND

While 50% of U.S. medical students are women, this fails to translate to cardiology: gender disparities are striking in interventional cardiology (IC) and electrophysiology (EP) and in leadership. Left atrial appendage closure with the WATCHMAN device, as a novel procedure, is a lens into inequities.

OBJECTIVE

To identify characteristics and prevalence of women: 1) as early WATCHMAN implanters, and 2) in related leadership.

METHODS

Data was collected on WATCHMAN implanters and hospitals from January 2017-December 2018. The gender of physicians in leadership positions was identified via survey: Director of IC and EP, and Chief of Cardiology. Firth's logistic model controlling for covariates modeled the rare event of a woman implanter.

RESULTS

Data obtained on 100% of cohort. Men comprised 97% of implanters (860/886). No difference in subspecialty or implants by gender. There were 414 hospitals performing WATCHMAN: 24% academic, 97% urban, and most medium/large sized (94%). EP made up 61% of implanters. Only 4.8% of hospitals had women in selected leadership roles. Women represented <1% of Directors of IC and only 2.6% of both Directors of EP and Chiefs of Cardiology. Hospitals with a woman in leadership had four times greater odds of a woman implanter (OR=4.24, 95% CI 1.16-15.41, p=0.028).

CONCLUSIONS AND RELEVANCE

Women are underrepresented in cardiology procedural subspecialties in use of novel technology and key leadership roles. There was a greater odds of women early implanters of WATCHMAN if a woman led locally. Increasing women in leadership may improve gender diversity though visibility of role models.

Comparative effectiveness of CRT in older patients with heart failure: Systematic review and meta-analysis

OBJECTIVE

To perform meta-analyses comparing safety and effectiveness of cardiac resynchronization therapy (CRT) in older versus younger patients with heart failure with reduced ejection fraction (HFrEF).

BACKGROUND

Pivotal CRT trials enrolled patients with HFrEF significantly younger than the typical contemporary patient with HFrEF. Thus, risks and benefits in this older population with HFrEF are largely unknown.

METHODS

PubMed, The Cochrane Library, Scopus, and Web of Science were queried for comparative effectiveness studies of CRT in older HFrEF patients. Title, abstract, and full text screening was performed to identify studies comparing at least one pre-specified endpoint between older and younger adult patients with at least 50 participants. Random effects meta-analysis in LVEF mean difference (older minus younger) and relative risk (RR) of death, improvement in New York Heart Association (NYHA) class, and complications are reported along with estimates of heterogeneity.

RESULTS

In 7 studies, there was similar LVEF improvement between groups [mean difference 1.14; 95% CI -0.04 - 2.32, p=0.06, I 2 =53%]. Older patients were equally likely as younger patients to see an improvement in NYHA class of at least 1 in 6 studies [RR 0.99; 95% CI, 0.93 - 1.06; p=0.76; I 2 =25%]. No significant differences in the incidence of hematoma, pneumothorax, lead dislodgment, cardiac perforation, or infection requiring explant was observed. RR of mortality in 11 studies demonstrated higher risk of all-cause mortality in older patients [RR 1.05; 95% CI, 1.03 - 1.08, p<0.01, I 2 =0%].

CONCLUSIONS

Compared with younger patients, older patients receiving CRT were equally likely to experience improvement in LVEF, LVEDD, and NYHA class. There was no difference in procedural complications. The higher rate of all-cause mortality in older patients likely reflects a greater underlying risk of death from competing causes.

Comparative outcomes of Riata and Fidelis lead management strategies: Results from the NCDR-ICD Registry

BACKGROUND

The Medtronic Sprint Fidelis® and Abbott Riata®/Riata ST® leads are at risk of failure and are subject to FDA recall. Comparative risks of various lead management strategies during elective generator change in a multi-center population are unknown. We aim to describe patients with functional, recalled ICD leads undergoing elective generator replacement and report outcomes according to lead management strategies.

METHODS

Using data from the NCDR ICD Registry, patients with a functioning Riata® or Fidelis® lead undergoing generator replacement are described according to lead management: reuse, abandon/replace, and extract/replace. Adjusted rates of death and pre-discharge complications are reported.

RESULTS

There were 13,144 generator replacement procedures involving a functioning, non-infected Riata® or Fidelis® lead (extraction n = 414, abandonment n = 427). Extraction patients were younger (mean 58 vs. 67 years) with fewer comorbidities than the reuse group. Maximum lead dwell time was similar between groups with average 94, 90, and 99 months in the extraction, abandonment, and reuse groups, respectively. In-hospital complications or mortality were more common in the extraction group (10.14%, 4.35%) compared with abandonment (1.64%, 0.47%) and reuse (0.22%, 0.07%). Compared with reuse, the adjusted odds of death or pre-discharge complication were significantly higher in the extraction group (OR 7.77 95% CI 2.42-24.95, p < .001) but not the abandonment group (OR 1.70 95% CI 0.52-5.61, p = .38).

CONCLUSIONS

In this real-world population, extraction of functional recalled ICD leads was associated with significant risk of in-hospital mortality and complications. Additional work is needed to clarify whether longer term outcomes balance these peri-procedural risks.

What Should Cardiac Patients Know About Device Cybersecurity Prior to Implantation?

Cardiac implantable electronic device (CIED) procedures require informed consent and, ideally, shared decision making to guide patients through their experiences as CIED recipients. The information that different patients need or want about cybersecurity risk varies. This article considers device cybersecurity risks in light of federal guidelines and suggests strategies for communicating these risks clearly during informed consent conversations and follow-up.

Sex Differences in Procedural Outcomes Among Patients Undergoing Left Atrial Appendage Occlusion: Insights From the NCDR LAAO Registry

Importance

Left atrial appendage occlusion (LAAO) has emerged as an alternative to anticoagulation for select patients with atrial fibrillation; however, women have been underrepresented in clinical trials of LAAO, and sex-specific subanalyses are limited.

Objective

To evaluate the sex differences in the baseline characteristics of patients undergoing LAAO implant and in the in-hospital outcomes after LAAO implant.

Design, Setting, and Participants

A total of 49 357 patients in the National Cardiovascular Data Registry LAAO Registry undergoing LAAO with the Watchman device between January 1, 2016, and June 30, 2019, were included in this study.

Exposure

Female or male sex.

Main Outcomes and Measures

The primary outcomes were aborted or canceled procedure, major adverse event, any adverse event, prolonged hospital stay longer than 1 day, and death. Unadjusted and multivariable adjusted logistic regression analyses were performed to assess sex differences in in-hospital adverse events.

Results

In this cohort study of 49 357 patients (mean [SD] age, 76.1 [8.0] years), 20 388 women (41.3%) and 28 969 (58.7%) men underwent LAAO. Compared with men, women were older and had a higher prevalence of paroxysmal atrial fibrillation, prior stroke, and uncontrolled hypertension but a lower prevalence of congestive heart failure, diabetes, and coronary artery disease. After multivariable adjustment, there were no differences in aborted or canceled procedures between women and men (613 [3.0%] vs 851 [2.9%]; odds ratio [OR] 1.01, 95% CI, 0.90-1.13). Women were more likely than men to experience any adverse event (1284 [6.3%] vs 1144 [3.9%]; P < .001; OR, 1.63; 95% CI, 1.49-1.77; P < .001) or major adverse event (827 [4.1%] vs 567 [2.0%]; P < .001; OR, 2.06; 95% CI, 1.82-2.34; P < .001) owing to pericardial effusion requiring drainage (241 [1.2%] vs 144 [0.5%]) or major bleeding (349 [1.7%] vs 244 [0.8%]). Women were also more likely than men to experience a hospital stay longer than 1 day (3272 [16.0%] vs 3355 [11.6%]; P < .001; adjusted OR, 1.46; 95% CI, 1.38-1.54; P < .001) or death (adjusted OR, 2.01; 95% CI, 1.31-3.09; P = .001), although death was rare and absolute differences were minimal (58 [0.3%] vs 37 [0.1%]; P < .001).

Conclusions and Relevance

This study suggests that, compared with men, women have a significantly higher risk of in-hospital adverse events after LAAO. Further research aimed at risk reduction, particularly strategies to reduce the risk of pericardial effusion and major bleeding, in women undergoing LAAO is warranted.

Efficacy and safety of dronedarone across age and sex subgroups: a post hoc analysis of the ATHENA study among patients with non-permanent atrial fibrillation/flutter

AIMS

Age and sex may impact the efficacy of antiarrhythmic drugs on cardiovascular outcomes and arrhythmia recurrences in patients with atrial fibrillation (AF). We report on a post hoc analysis of the ATHENA study (NCT00174785), which examined cardiovascular outcomes in patients with non-permanent AF treated with dronedarone vs. placebo.

METHODS AND RESULTS

Efficacy and safety of dronedarone were assessed in patients according to age and sex. Baseline characteristics were comparable across subgroups, except for cardiovascular comorbidities, which were more frequent with increasing age. Dronedarone significantly reduced the risk of cardiovascular hospitalization or death due to any cause among patients 65-74 [n = 1830; hazard ratio (HR) 0.71, 95% confidence interval (CI) 0.60-0.83; P < 0.0001] and ≥75 (n = 1925; HR 0.75, 95% CI 0.65-0.88; P = 0.0002) years old and among males (n = 2459; HR 0.74, 95% CI 0.64-0.84; P < 0.00001) and females (n = 2169; HR 0.77, 95% CI 0.67-0.89; P = 0.0002); outcomes were similar for time to AF/AFL recurrence. Among patients aged <65 years (n = 873), cardiovascular hospitalization or death due to any cause with dronedarone vs. placebo was associated with an HR of 0.89 (95% CI 0.71-1.11; P = 0.3). The incidence of all treatment-emergent adverse events (TEAEs) and TEAEs leading to treatment discontinuation was comparable among males and females, and increased with increasing age.

CONCLUSIONS

These results support the use of dronedarone for the improvement of clinical outcomes among patients aged ≥65 years and regardless of sex.

Funding of Studies Supporting IA Guideline Recommendations in Cardiovascular Medicine-A Systematic Review

Each guideline recommendation from the American Heart Association and the American College of Cardiology includes an indication of the level of supporting evidence and the associated strength of recommendation with “IA” recommendations representing those with the highest quality supporting evidence and the least amount of uncertainty for benefit. In this analysis, study type and funding sources were systematically tabulated across these IA guideline recommendations over the past 5 years. Nearly half of studies supporting IA guideline recommendations were randomized controlled trials (45%). Overall, about one third of studies supporting IA recommendations were publicly funded (34.9%) with slightly more funded through industry sources (43.5%). Funding sources varied based on the type of intervention being studied with randomized controlled trials of device, diagnostic, and pharmacological interventions reflecting predominantly industry‐funded studies. Over time, studies supporting IA cardiology guideline are funded by industry about twice as often as public sources. Thus, data of adequate quality to support cardiovascular guideline recommendations come from a variety of sources.

Association Between Sex and Treatment Outcomes of Atrial Fibrillation Ablation Versus Drug Therapy: Results From the CABANA Trial

BACKGROUND

Among patients with atrial fibrillation (AF), women are less likely to receive catheter ablation and may have more complications and less durable results. Most information about sex-specific differences after ablation comes from observational data. We prespecified an examination of outcomes by sex in the 2204-patient CABANA trial (Catheter Ablation Versus Antiarrhythmic Drug Therapy for Atrial Fibrillation).

METHODS

CABANA randomized patients with AF age ≥65 years or <65 years with ≥1 risk factor for stroke to a strategy of catheter ablation with pulmonary vein isolation versus drug therapy with rate/rhythm control agents. The primary composite outcome was death, disabling stroke, serious bleeding, or cardiac arrest, and key secondary outcomes included AF recurrence.

RESULTS

CABANA randomized 819 (37%) women (ablation 413, drug 406) and 1385 men (ablation 695, drug 690). Compared with men, women were older (median age, 69 years versus 67 years for men), were more symptomatic (48% Canadian Cardiovascular Society AF Severity Class 3 or 4 versus 39% for men), had more symptomatic heart failure (42% with New York Heart Association Class ≥II versus 32% for men), and more often had a paroxysmal AF pattern at enrollment (50% versus 39% for men) (P<0.0001 for all). Women were less likely to have ancillary (nonpulmonary vein) ablation procedures performed during the index procedure (55.7% versus 62.2% in men, P=0.043), and complications from treatment were infrequent in both sexes. For the primary outcome, the hazard ratio for those who underwent ablation versus drug therapy was 1.01 (95% CI, 0.62-1.65) in women and 0.73 (95% CI, 0.51-1.05) in men (interaction P value=0.299). The risk of recurrent AF was significantly reduced in patients undergoing ablation compared with those receiving drug therapy regardless of sex, but the effect was greater in men (hazard ratio, 0.64 [95% CI, 0.51-0.82] for women versus hazard ratio, 0.48 [95% CI, 0.40-0.58] for men; interaction P value=0.060).

CONCLUSIONS

Clinically relevant treatment-related strategy differences in the primary and secondary clinical outcomes of CABANA were not seen between men and women, and there were no sex differences in adverse events. The CABANA trial results support catheter ablation as an effective treatment strategy for both women and men. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00911508.