Optimizing mechanically sensed atrial tracking in patients with atrioventricular-synchronous leadless pacemakers: A single-center experience

Background

Atrioventricular (AV)-synchronous single-chamber leadless pacing using a mechanical atrial sensing algorithm produced high AV synchrony in clinical trials, but clinical practice experience with these devices has not yet been described.

Objective

To describe pacing outcomes and programming changes with AV-synchronous leadless pacemakers in clinical practice.

Methods

Consecutive patients without persistent atrial fibrillation who received an AV-synchronous leadless pacemaker and completed follow-up between February 2020 and April 2021 were included. We evaluated tracking index (atrial mechanical sense followed by ventricular pace [AM-VP] divided by total VP), total AV synchrony (sum of AM-ventricular sense [AM-VS], AM-VP, and AV conduction mode switch), use of programming optimization, and improvement in AV synchrony after optimization.

Results

Fifty patients met the inclusion criteria. Mean age was 69 ± 16.8 years, 24 (48%) were women, 24 (48%) had complete heart block, and 17 (34%) required ≥50% pacing. Mean tracking index was 41% ± 34%. Thirty-five patients (70%) received ≥1 programming change. In 36 patients with 2 follow-up visits, tracking improved by +9% ± 28% (P value for improvement = .09) and +18% ± 19% (P = .02) among 15 patients with complete heart block. Average total AV synchrony increased from 89% [67%, 99%] to 93% [78%, 100%] in all patients (P = .22), from 86% [52%, 98%] to 97% [82%, 99%] in those with complete heart block (P = .04), and from 73% [52%, 80%] to 78% [70%, 85%] in those with ≥50% pacing (P = .09).

Conclusion

In patients with AV-synchronous leadless pacemakers, programming changes are frequent and are associated with increased atrial tracking and increased AV synchrony in patients with complete heart block.

Race Differences in Interventions and Survival After Out-of-Hospital Cardiac Arrest in North Carolina, 2010 to 2014

Background

Following the implementation of the HeartRescue project, with interventions in the community, emergency medical services, and hospitals to improve care and outcomes for out‐of‐hospital cardiac arrests (OHCA) in North Carolina, improved bystander and first responder treatments as well as survival were observed. This study aimed to determine whether these improvements were consistent across Black versus White individuals.

Methods and Results

Using the Cardiac Arrest Registry to Enhance Survival (CARES), we identified OHCA from 16 counties in North Carolina (population 3 million) from 2010 to 2014. Temporal changes in interventions and outcomes were assessed using multilevel multivariable logistic regression, adjusted for patient and socioeconomic neighborhood‐level factors. Of 7091 patients with OHCA, 36.5% were Black and 63.5% were White. Black patients were younger, more females, had more unwitnessed arrests and non‐shockable rhythm (Black: 81.0%; White: 75.4%). From 2010 to 2014, the adjusted probabilities of bystander cardiopulmonary resuscitation (CPR) went from 38.5% to 51.2% in White, P<0.001; and 36.9% to 45.6% in Black, P=0.002, and first‐responder defibrillation went from 13.2% to 17.2% in White, P=0.002; and 14.7% to 17.3% in Black, P=0.16. From 2010 to 2014, survival to discharge only increased in White (8.0% to 11.4%, P=0.004; Black 8.9% to 9.5%, P=0.60), though, in shockable patients the probability of survival to discharge went from 24.8% to 34.6% in White, P=0.02; and 21.7% to 29.0% in Black, P=0. 10.

Conclusions

After the HeartRescue program, bystander CPR and first‐responder defibrillation increased in both patient groups; however, survival only increased significantly for White patients.

Sex Differences in Coronary Artery Bypass Grafting Techniques: A STS Database Analysis

BACKGROUND

Females with coronary artery disease (CAD) have inferior outcomes compared with males, including higher mortality following coronary artery bypass grafting (CABG). We aimed to evaluate the association of female sex with the use of guideline-concordant CABG revascularization techniques.

METHODS

The Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database was queried for adult patients who underwent first-time isolated CABG in the US from 2011-2019. The association between female sex and the odds of (1) receiving a left internal mammary artery (LIMA) graft for revascularization of the left anterior descending (LAD) artery, (2) undergoing complete revascularization, and (3) undergoing multi-arterial grafting was assessed, adjusting for procedural anatomy.

RESULTS

Among 1,212,487 patients meeting inclusion criteria, 75% were male (n=911,178) and 25% were female (n=301,309). Female sex was associated with lower unadjusted rates of revascularization with an IMA (93.9% vs 95.9%, P<.001), bilateral IMA (2.9% vs 5.6%, P<.001) or radial artery (3.2% vs 5.6%, P<.001) graft. After adjustment, females had a lower odds than males of receiving a LIMA graft to the LAD (adjusted odds ratio [AOR] 0.79, 95% CI 0.75-0.83, P<.001), undergoing complete revascularization (AOR 0.86, 95% CI 0.83-0.90, P<.001), and undergoing multi-arterial grafting (AOR 0.78, 95% CI 0.75-0.81, P<.001).

CONCLUSIONS

Female sex was associated with a 14-22% lower odds of undergoing guideline concordant revascularization including LIMA to LAD grafting, multi-arterial grafting, and complete revascularization. Further investigation is necessary to determine why revascularization approaches differ by sex and to what degree sex disparities in CAD outcomes are due to surgical approach.

Ablation Versus Drug Therapy for Atrial Fibrillation in Racial and Ethnic Minorities

BACKGROUND

Rhythm control strategies for atrial fibrillation (AF), including catheter ablation, are substantially underused in racial/ethnic minorities in North America.

OBJECTIVES

This study sought to describe outcomes in the CABANA trial as a function of race/ethnicity.

METHODS

CABANA randomized 2,204 symptomatic participants with AF to ablation or drug therapy including rate and/or rhythm control drugs. Only participants in North America were included in the present analysis, and participants were subgrouped as racial/ethnic minority or nonminority with the use of National Institutes of Health definitions. The primary endpoint was a composite of death, disabling stroke, serious bleeding, or cardiac arrest.

RESULTS

Of 1,280 participants enrolled in CABANA in North America, 127 (9.9%) were racial and ethnic minorities. Compared with nonminorities, racial and ethnic minorities were younger with median age 65.6 versus 68.5 years, respectively, and had more symptomatic heart failure (37.0% vs 22.0%), hypertension (92.1% vs 76.8%, respectively), and ejection fraction <40% (20.8% vs 7.1%). Racial/ethnic minorities treated with ablation had a 68% relative reduction in the primary endpoint (adjusted hazard ratio [aHR]: 0.32; 95% confidence interval [CI]: 0.13-0.78) and a 72% relative reduction in all-cause mortality (aHR: 0.28; 95% CI: 0.10-0.79). Primary event rates in racial/ethnic minority and nonminority participants were similar in the ablation arm (4-year Kaplan-Meier event rates 12.3% vs 9.9%); however, racial and ethnic minorities randomized to drug therapy had a much higher event rate than nonminority participants (27.4% vs. 9.4%).

CONCLUSION

Among racial or ethnic minorities enrolled in the North American CABANA cohort, catheter ablation significantly improved major clinical outcomes compared with drug therapy. These benefits, which were not seen in nonminority participants, appear to be due to worse outcomes with drug therapy. (Catheter Ablation vs Anti-arrhythmic Drug Therapy for Atrial Fibrillation Trial [CABANA]; NCT00911508).

Percutaneous left atrial appendage occlusion: A review of current devices, clinical evidence, patient selection, and post procedural antithrombotic management

Stroke is a major driver of increased morbidity and mortality in patients with non-valvular atrial fibrillation (NVAF). While systemic oral anticoagulation (OAC) continues to be the mainstay for stroke reduction therapy in patients with NVAF, several barriers prevent the sustained long-term use of OAC, including increased risk of bleeding, non-compliance, cost, drug-drug interactions, and the need for ongoing laboratory testing. Given the need for continued stroke reduction therapies in patients who are intolerant of or non-compliant with OAC, percutaneous left atrial appendage (LAA) occlusion (LAAO) has emerged as a nonpharmacologic alternative to OAC. The development of percutaneous LAAO techniques is based on data suggesting that more than 90% of thrombi in patients with NVAF originate in the LAA. Two percutaneous LAAO devices are currently in widespread clinical use: Watchman (United States and Europe) and the Amplatzer type of devices (Europe); randomized trial data exist only for the Watchman device. Multiple randomized and nonrandomized trials and registries have demonstrated the safety and effectiveness of LAAO in patients who are suitable for short-term anticoagulation using a variety of post-procedural antithrombotic strategies. Ongoing randomized clinical trials on LAAO are focused on OAC-ineligible patients to compare efficacy of LAAO devices against a multitude of antithrombotic options. This review aims to discuss the rationale and evidence for LAAO and post procedural antithrombotic strategies and opportunities for research examination. In addition, we discuss the need for continued investigation of LAAO in populations not well represented in clinical trials or registries, including women, older patients, and underrepresented racial and ethnic groups.

African American-Caucasian American differences in aortic valve replacement in patients with severe aortic stenosis

BACKGROUND

Among patients with severe aortic stenosis (AS), there are limited data on aortic valve replacement (AVR), reasons for nonreceipt and mortality by race.

METHODS

Utilizing the Duke Echocardiography Laboratory Database, we analyzed data from 110,711 patients who underwent echocardiography at Duke University Medical Center between 1999 and 2013. We identified 1,111 patients with severe AS who met ≥1 of 3 criteria for AVR: ejection fraction ≤50%, diagnosis of heart failure, or need for coronary artery bypass surgery. Logistic regression models were used to assess the association between race, AVR and 1-year mortality. χ2 testing was used to assess potential racial differences in reasons for AVR nonreceipt.

RESULTS

Among the 1,111 patients (143 AA and 968 CA) eligible for AVR, AA were more often women, had more diabetes, renal insufficiency, aortic regurgitation and left ventricular hypertrophy. CA were more often smokers, had more ischemic heart disease, hyperlipidemia and higher median income levels. There were no racial differences in surgical risk utilizing logistic euroSCORES. Relative to CA, AA had lower rates of AVR (adjusted odds ratio 0.46, 95% CI 0.3-0.71, P < .001) yet similar 1-year mortality (aHR 0.81, 95% CI 0.57-1.17, P = .262). There were no significant differences in reasons for AVR nonreceipt.

CONCLUSIONS

We identified 143 African Americans (AA) and 968 Caucasian Americans(CA) with severe AS who met prespecified criteria for AVR.. AA relative to CA were more often women, had more diabetes, renal insufficiency, and left ventricular hypertrophy, however had less tobacco use, ischemic heart disease, hyperlipidemia and lower median income levels. Among patients with severe AS, AA relative to CA had lower rates of AVR (adjusted odds ratio 0.46, 95% CI 0.3-0.71, P < .001) without significant differences in reasons for AVR nonreceipt and similar 1-year mortality.

Racial Differences in AKI Incidence Following Percutaneous Coronary Intervention

BACKGROUND

Undergoing percutaneous coronary intervention (PCI) is a risk factor for AKI development, but few studies have quantified racial differences in AKI incidence after this procedure.

METHODS

We examined the association of self-reported race (Black, White, or other) and baseline eGFR with AKI incidence among patients who underwent PCI at Duke University Medical Center between January 1, 2003, and December 31, 2013. We defined AKI as a 0.3 mg/dl absolute increase in serum creatinine within 48 hours, or ≥1.5-fold relative elevation within 7 days post-PCI from the reference value ascertained within 30 days before PCI.

RESULTS

Of 9422 patients in the analytic cohort (median age 63 years; 33% female; 75% White, 20% Black, 5% other race), 9% developed AKI overall (14% of Black, 8% of White, 10% of others). After adjustment for demographics, socioeconomic status, comorbidities, predisposing medications, PCI indication, periprocedural AKI prophylaxis, and PCI procedural characteristics, Black race was associated with increased odds for incident AKI compared with White race (odds ratio [OR], 1.79; 95% confidence interval [95% CI], 1.48 to 2.15). Compared with Whites, odds for incident AKI were not significantly higher in other patients (OR, 1.30; 95% CI, 0.93 to 1.83). Low baseline eGFR was associated with graded, higher odds of AKI incidence (P value for trend <0.001); however, there was no interaction between race and baseline eGFR on odds for incident AKI (P value for interaction = 0.75).

CONCLUSIONS

Black patients had greater odds of developing AKI after PCI compared with White patients. Future investigations should identify factors, including multiple domains of social determinants, that predispose Black individuals to disparate AKI risk after PCI.

Perceived Versus Actual Risks of 30-Day Readmission in Patients With Cardiovascular Disease

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of hospitalization in the United States, and patients with CVD are at a high risk of readmission after discharge. We examined whether patients' perceived risk of readmission at discharge was associated with actual 30-day readmissions in patients hospitalized with CVD.

METHODS

We recruited 730 patients from the Duke Heart Center who were admitted for treatment of CVD between January 1, 2015, and August 31, 2017. A standardized survey was linked with electronic health records to ascertain patients' perceived risk of readmission, and other sociodemographic, psychosocial, behavioral, and clinical data before discharge. All-cause readmission within 30 days after discharge was examined.

RESULTS

Nearly 1-in-3 patients perceived a high risk of readmission at index admission and those who perceived a high risk had significantly more readmissions within 30 days than patients who perceived low risks of readmission (23.6% versus 15.8%, P=0.016). Among those who perceived a high risk of readmission, non-White patients (odds ratio [OR], 2.07 [95% CI, 1.28-3.36]), those with poor self-rated health (OR, 2.30 [95% CI, 1.38-3.85]), difficulty accessing care (OR, 2.72 [95% CI, 1.24-6.00]), and prior hospitalizations in the past year (OR, 2.13 [95% CI, 1.21-3.74]) were more likely to be readmitted. Among those who perceived a low risk of readmission, patients who were widowed (OR, 2.69 [95% CI, 1.60-4.51]) and reported difficulty accessing care (OR, 1.89 [95% CI, 1.07-3.33]) were more likely to be readmitted.

CONCLUSIONS

Patients who perceived a high risk of readmission had a higher rate of 30-day readmission than patients who perceived a low risk. These findings have important implications for identifying CVD patients at a high risk of 30-day readmission and targeting the factors associated with perceived and actual risks of readmission.

Evaluation of Women and Underrepresented Racial and Ethnic Group Representation in a General Cardiology Fellowship After a Systematic Recruitment Initiative

IMPORTANCE

The proportion of women and underrepresented racial and ethnic groups (UREGs) matriculating into general cardiology fellowships remains low.

OBJECTIVE

To assess a systematic recruitment initiative aimed at ensuring adequate matriculation of women and UREGs in a general cardiology fellowship.

DESIGN, SETTING, AND PARTICIPANTS

This quality improvement study took place at a large, tertiary academic medical center and associated Accreditation Council for Graduate Medical Education Cardiovascular Disease fellowship. Participants included cardiology fellowship and divisional leadership and general cardiology fellow applicants to the Duke Cardiovascular Disease Fellowship Program from 2017 to 2019. Data analysis was performed from December 2019 to May 2020.

EXPOSURE

Multipronged initiative that created an environment committed to ensuring equity of opportunity. This included the creation of a fellowship diversity and inclusivity task force that drafted recommendations, which included reorganization of the fellowship recruitment committee, and changes to the applicant screening process, the interview day, applicant ranking process, and postmatch interventions.

MAIN OUTCOMES AND MEASURES

The percentage of matriculating and overall women and UREGs before and after the interventions were recorded.

RESULTS

The fellowship received a mean (SD) of 462 (55) applications annually before the interventions (2006-2016) and 611 (27) applications annually after the interventions (2017-2019). Between the 10-year period before the interventions and the 3-year period during the interventions, there was a significant increase in the annual mean (SD) percentage of women (22.4% [2.9%] vs 26.4% [0.07%]; P < .001) and UREG applicants (10.5% [1.1%] vs 12.5% [1.9%]; P = .01) to the program. Among applicants interviewed, the percentage of women increased from 20.0% to 33.5% (P = .01) and that of and UREGs increased from 14.0% to 20.0% (P = .01). Before the interventions, a mean (SD) of 23.2% (16.2%) women and 9.7% (7.8%) UREGs matriculated as first-year fellows, whereas after the interventions, a mean (SD) of 54.2% (7.2%) women and 33.3% (19.0%) UREGs matriculated as first-year fellows. The proportion of the entire fellowship who were women increased from a 5-year mean (SD) of 27.0% (8.8%) to 54.2% (7.2%) after 3 years of interventions, and that of UREGs increased from 5.6% (4.6%) to 33.3% (19.0%). Overall, the proportion of applicants in the entire population who were either women or from UREGs increased from 27.8% to 66.7%.

CONCLUSIONS AND RELEVANCE

After implementing interventions to promote equity of opportunity in the cardiovascular disease fellowship, the percentage of women and UREGs significantly increased in the fellowship over a 3-year time period. These interventions may be applicable to other cardiovascular disease fellowships seeking to diversify training programs.

Catheter ablation of atrial fibrillation in cardiac amyloidosis

BACKGROUND

Cardiac amyloidosis is a progressive infiltrative disease involving deposition of amyloid fibrils in the myocardium and cardiac conduction system that frequently manifests with heart failure (HF) and arrhythmias, most frequently atrial fibrillation (AF), atrial flutter (AFL), and atrial tachycardia (AT).

METHODS

We performed an observational retrospective study of patients with a diagnosis of cardiac amyloid who underwent catheter ablation at our institution between January 1, 2011 and December 1, 2018. Patient demographics, procedural characteristics, and outcomes were determined by manual chart review.

RESULTS

A total of 13 catheter ablations were performed over the study period in patients with cardiac amyloidosis, including 10 AT/AF/AFL ablations and three atrioventricular nodal ablations. Left ventricular ejection fraction was lower at the time of AV node ablation than catheter ablation of AT/AF/AFL (23% vs 40%, P = .003). Cardiac amyloid was diagnosed based on the results of preablation cardiac MRI results in the majority of patients (n = 7, 70%). The HV interval was prolonged at 60 ± 15 ms and did not differ significantly between AV nodal ablation patients and AT/AF/AFL ablation patients (69 ± 18 ms vs 57 ± 14 ms, P = .36). The majority of patients undergoing AT/AF/AFL ablation had persistent AF (n = 7, 70%) and NYHA class II (n = 5, 50%) or III (n = 5, 50%) HF symptoms, whereas patients undergoing AV node ablation were more likely to have class IV HF (n = 2, 66%, P = .014). Arrhythmia-free survival in CA patients after catheter ablation of AT/AF/AFL was 40% at 1 year and 20% at 2 years.

CONCLUSIONS

Catheter ablation of AT/AF/AFL may be a feasible strategy for appropriately selected patients with early to mid-stage CA, whereas AV node ablation may be more appropriate in patients with advanced-stage CA.

Catheter ablation of atrial fibrillation in patients with diabetes mellitus

BACKGROUND

Diabetes mellitus (DM) is an independent risk factor for atrial fibrillation (AF). Few studies have compared clinical outcomes after catheter ablation between patients with and those without DM.

OBJECTIVE

The purpose of this study was to compare AF ablation outcomes in patients with and those without DM.

METHODS

We performed a retrospective analysis of 351 consecutive patients who underwent first-time AF ablation. Clinical outcomes included freedom from recurrent atrial arrhythmia, symptom burden (Mayo AF Symptom Inventory score), cardiovascular and all-cause hospitalizations, and periprocedural complications.

RESULTS

Patients with DM (n = 65) were older, had a higher body mass index, more persistent AF, more hypertension, and larger left atrial diameter (P <.05 for all). Median (Q1, Q3) total radiofrequency duration [64.0 (43.6, 81.4) minutes vs 54.3 (39.2, 76.4) minutes; P = .132] and periprocedural complications (P = .868) did not differ between patients with and those without DM. After a median follow-up of 29.5 months, arrhythmia recurrence was significantly higher in the DM group compared to the no-DM group after adjustment for baseline differences (adjusted hazard ratio [HR] 2.24; 95% confidence [CI] 1.42-3.55; P = .001). There was a nonsignificant trend toward higher AF recurrence with worse glycemic levels (HR 1.29; 95% CI 0.99-1.69; P = .064).

CONCLUSION

Although safety outcomes associated with AF ablation were similar between patients with and those without DM, arrhythmia-free survival was significantly lower among patients with DM. Poor glycemic control seems to an important risk factor for AF recurrence.

Cardiovascular Health in American Indians and Alaska Natives: A Scientific Statement From the American Heart Association

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of death among American Indians and Alaska Natives. Over the past 50 years, the prevalence of CVD has been rising among American Indians and Alaska Natives. The objective of this statement is to summarize population-level risk factors and management techniques tailored for the American Indian and Alaska Native populations.

METHODS

PubMed/MEDLINE, the Centers for Disease Control and Prevention, and the annual Heart Disease and Stroke Statistics report from the American Heart Association were used to identify risk factors and interventions specific to American Indians and Alaska Natives.

RESULTS

Diabetes mellitus is a major contributor to disproportionately higher rates of coronary heart disease among American Indians and Alaska Natives compared with other racial and ethnic groups. Additional risk factors for CVD include low-density lipoprotein cholesterol levels, hypertension, renal disease, age, and sex. Smoking and exposure to toxic metals are risk factors for some subpopulations. A quarter of American Indians live below the federal poverty line, and thus, low socioeconomic status is an important social determinant of cardiovascular health. Community-based interventions have reduced CVD risk in American Indians and Alaska Natives. Underreporting of American Indian and Alaska Native race could underestimate the extent of CVD in this population.

CONCLUSIONS

Prevention and treatment of CVD in American Indians and Alaska Natives should focus on control of risk factors and community-based interventions that address social determinants of health, particularly among individuals with diabetes mellitus. Accurate reporting of race/ethnicity is encouraged to address race-specific risk factors.

Safety and efficacy outcomes of left atrial posterior wall isolation compared to pulmonary vein isolation and pulmonary vein isolation with linear ablation for the treatment of persistent atrial fibrillation

BACKGROUND

Pulmonary wall isolation (PWI) is increasingly used as an adjunctive lesion set to compliment pulmonary vein isolation (PVI), especially in patients with persistent atrial fibrillation (AF). The objective was to compare outcomes of catheter ablation in patients with persistent AF undergoing PVI with and without adjunctive PWI.

METHODS

We performed a retrospective study of 558 patients who underwent de novo and repeat ablation for persistent AF. Subjects were matched using propensity score adjustments. Outcomes were freedom from recurrent atrial arrhythmia and adverse events.

RESULTS

Among 558 patients who underwent ablation for persistent AF, 78 (14%) underwent PVI + PWI, 255 (46%) underwent PVI, and 225 (40%) underwent PVI + linear ablation. Stratified logistic regression analysis with propensity matching revealed higher odds of recurrent arrhythmia with PVI + PWI when compared to PVI (odds ratio [OR] 2.25, 95% CI 1.08-4.69, P = .030) and when compared to PVI + linear (OR 2.31, 95% CI 1.01-5.28, P = .048). Within the PVI + PWI group, 57.7% of subjects were in normal sinus rhythm at 6 months compared to 73.9% and 72.2% in PVI and PVI + linear groups, respectively. Adverse events were rare, with 19 events total identified across all groups.

CONCLUSIONS

PVI + PWI does not appear to be as effective as PVI or PVI + linear ablation in reducing the recurrence of arrhythmia within 6 months of the index procedure in patients with persistent AF. A prospective, randomized controlled trial comparing these ablation techniques is needed to clarify the role of extensive substrate modification for treatment of persistent AF.

CONDENSED ABSTRACT

PWI is increasingly used as an adjunctive lesion set to compliment PVI in patients with persistent AF. We performed a retrospective study of 558 patients who underwent de novo and repeat ablation for persistent AF to compare the outcomes between PVI with and without adjunctive PWI. We found an increased incidence in recurrence of AF and other atrial arrhythmias at 6 months in the PVI + PWI cohort compared to PVI with or without additional linear ablation. A prospective, randomized controlled trial comparing these ablation techniques is needed to clarify the role of extensive substrate modification for treatment of persistent AF.

Effectiveness of catheter ablation of atrial fibrillation according to heart failure etiology

BACKGROUND

Catheter ablation is an important rhythm control therapy in patients with atrial fibrillation (AF) with concomitant heart failure (HF). The objective of this study was to assess the comparative efficacy of AF ablation patients with ischemic vs nonischemic heart failure.

METHODS

We conducted a retrospective, observational cohort study of patients with HF who underwent AF ablation. Outcomes were compared based on HF etiology and included in-hospital events, symptoms (Mayo AF Symptom Inventory [MAFSI]), and functional status (New York Heart Association class) and freedom from atrial arrhythmias at 12 months.

RESULTS

Among 242 patients (n = 70 [29%] ischemic, n = 172 [71%] nonischemic), patients with nonischemic cardiomyopathy were younger (mean age 64 ± 11.5 vs 69 ± 9.1, P = .002), more often female (36% vs 17%, P = .004), and had higher mean left-ventricular ejection fraction (47% vs 42%, P = .0007). There were no significant differences in periprocedural characteristics, including mean procedure time (243 ± 74.2 vs 259 ± 81.8 minutes, P = .1) and nonleft atrial ablation (17% vs 20%, P = .6). All-cause adverse events were similar in each group (15% vs 17%, P = .7). NYHA and MAFSI scores improved significantly at follow-up and did not differ according to HF etiology (P = .5; P = .10-1.00 after Bonferroni correction). There were no significant differences in freedom from recurrent atrial arrhythmia at 12-months between ischemic (74%) and nonischemic patients (78%): adjusted RR 0.63, 95% confidence interval 0.33-1.19.

CONCLUSIONS

Catheter ablation in patients with AF and concomitant heart failure leads to significant improvements in functional and symptom status without significant differences between patients with ischemic vs nonischemic HF etiology.

Videos to reduce racial disparities in ICD therapy Via Innovative Designs (VIVID) trial: Rational, design and methodology

BACKGROUND

Despite a higher prevalence of sudden cardiac death (SCD), black individuals are less likely than whites to have an implantable cardioverter defibrillator (ICD) implanted. Racial differences in ICD utilization is in part explained by higher refusal rates in black individuals. Decision support can assist with treatment-related uncertainty and prepare patients to make well-informed decisions.

METHODS

The Videos to reduce racial disparities in ICD therapy Via Innovative Designs (VIVID) study will randomize 350 black individuals with a primary prevention indication for an ICD to a racially concordant/discordant video-based decision support tool or usual care. The composite primary outcome is (1) the decision for ICD placement in the combined video groups compared with usual care and (2) the decision for ICD placement in the racially concordant relative to discordant video group. Additional outcomes include knowledge of ICD therapy and SCD risk; decisional conflict; ICD receipt at 90 days; and a qualitative assessment of ICD decision making in acceptors, decliners, and those undecided.

CONCLUSIONS

In addition to assessing the efficacy of decision support on ICD acceptance among black individuals, VIVID will provide insight into the role of racial concordance in medical decision making. Given the similarities in the root causes of racial/ethnic disparities in care across health disciplines, our approach and findings may be generalizable to decision making in other health care settings.

Predicting atrial fibrillation recurrence after ablation in patients with heart failure: Validity of the APPLE and CAAP-AF risk scoring systems

BACKGROUND

Compared with medical therapy, catheter ablation of atrial fibrillation (AF) in patients with heart failure (HF) improves cardiovascular outcomes. Risk scores (CAAP-AF and APPLE) have been developed to predict the likelihood of AF recurrence after ablation, have not been validated specifically in patients with AF and HF.

METHODS

We analyzed baseline characteristics, risk scores, and rates of AF recurrence 12 months postablation in a cohort of 230 consecutive patients with AF and HF undergoing PVI in the Duke Center for Atrial Fibrillation registry from 2009-2013.

RESULTS

During a follow-up period of 12 months, 76 of 230 (33%) patients with HF experienced recurrent AF after ablation. The median APPLE and CAAP-AF scores were 1.5 ([Q1, Q3]: [1.0, 2.0]) and 4.0 ([Q1, Q3]: [3.0, 5.0]), respectively and were not different from those patients with and without recurrent AF. Freedom from AF was not different according to APPLE and CAAP-AF scores. Discrimination for recurrent AF with the CAAP-AF score was modest with a C-statistic of 0.60 (95% CI 0.52-0.67). Discrimination with the APPLE score was similarly modest, with a C-statistic of 0.54 (95% CI: 0.47-0.62).

CONCLUSIONS

Validated predictive risk scores for recurrent AF after catheter ablation exhibit limited predictive ability in cohorts of AF and HF. Additional tools are needed to facilitate risk stratification and patient selection for AF ablation in patients with concomitant HF.

Representativeness of a Heart Failure Trial by Race and Sex: Results From ASCEND-HF and GWTG-HF

OBJECTIVES

This study sought to determine the degree to which U.S. patients enrolled in a heart failure (HF) trial represent patients in routine U.S. clinical practice according to race and sex.

BACKGROUND

Black patients and women are frequently under-represented in HF clinical trials. However, the degree to which black patients and women enrolled in trials represent such patients in routine practice is unclear.

METHODS

The ASCEND-HF (Acute Study of Clinical Effectiveness of Nesiritide in Decompensated Heart Failure) trial randomized patients hospitalized for HF to receive nesiritide or placebo from May 2007 to August 2010 and was neutral for clinical endpoints. This analysis compared non-Hispanic white (n = 1,494) and black (n = 1,012) patients enrolled in ASCEND-HF from the U.S. versus non-Hispanic white and black patients included in a U.S. hospitalized HF registry (i.e., Get With The Guidelines-Heart Failure [GWTG-HF]) during the ASCEND-HF enrollment period and meeting trial eligibility criteria.

RESULTS

Among 79,291 white and black registry patients, 49,063 (62%) met trial eligibility criteria (white, n = 37,883 [77.2%]; black, n = 11,180 [22.8%]). Women represented 35% and 49% of the ASCEND-HF and trial-eligible GWTG-HF cohorts, respectively. Compared with trial-enrolled patients, trial-eligible GWTG-HF patients tended to be older with higher blood pressure and higher ejection fraction. Trial-eligible patients had higher in-hospital mortality (2.3% vs. 1.3%), 30-day readmission (20.2% vs. 16.8%), and 180-day mortality (21.2% vs. 18.6%) than those enrolled in the trial (all p < 0.02), with consistent mortality findings by race and sex. After propensity score matching, mortality rates were similar; however, trial-eligible patients continued to have higher rates of 30-day readmission (23.1% vs. 17.3%; p < 0.01), driven by differences among black patients and women (all p for interaction ≤0.02).

CONCLUSIONS

Patients with HF seen in U.S. practice and eligible for the ASCEND-HF trial had worse clinical outcomes than those enrolled in the trial. After accounting for clinical characteristics, trial-eligible real-world patients continued to have higher rates of 30-day readmission, driven by differences among black patients and women. Social, behavioral, and other unmeasured factors may impair representativeness of patients enrolled in HF trials, particularly among racial/ethnic minorities and women. (Acute Study of Clinical Effectiveness of Nesiritide in Decompensated Heart Failure [ASCEND-HF]; NCT00475852).

Physicians' perceptions of shared decision-making for implantable cardioverter-defibrillators: Results of a physician survey

BACKGROUND

Centers for Medicare and Medicaid Services has mandated the use of shared decision-making (SDM) for implantable cardioverter-defibrillator (ICD) implantation. SDM tools help facilitate quality SDM by presenting patients with balanced evidence-based facts related to risk and benefits. Perceptions of ICD implantation may differ based on patients' sex and race.

OBJECTIVE

To determine if and how physicians are incorporating SDM in counseling patients about ICD and if they are aware of sex- and race-based differences in patients' perception of ICDs.

METHODS

This was a pilot study involving an online survey targeting attending physicians who implant ICDs. Physicians were randomly selected by a computer-based program; 350 surveys were sent.

RESULTS

Of the 124 (35%) respondents to the survey, 102 (84%) met the inclusion criteria, and of those, 99 (97%) were adult electrophysiologists. Most physicians (90, 88%) stated they engaged in SDM during the general consent process. Sixty-three (62%) physicians discuss end of life issues while obtaining general consent. Forty-four (43%) physicians said they use an existing SDM tool with the Colorado SDM tool being the most common (39, 89%). The majority of physicians were unaware of sex- and race-based differences in perceptions related to ICD implantation (sex 64, 63% and race 63, 62%).

CONCLUSION

A vast majority of physicians are engaging in SDM; however less than half are using a formal SDM tool, and a minority of physicians were aware of sex- and race-based differences in patients' perception of ICD implantation. Sex- and race-based tools might help address this gap.

Assessing heterogeneity of treatment effect analyses in health-related cluster randomized trials: A systematic review

Background

Cluster-randomized trials (CRTs) are being increasingly used to test a range of interventions, including medical interventions commonly used in clinical practice. Policies created by the NIH and the Food and Drug Administration (FDA) require the reporting of demographics and the examination of demographic heterogeneity of treatment effect (HTE) for individually randomized trials. Little is known about how frequent demographics are reported and HTE analyses are conducted in CRTs.

Objectives

We sought to understand the prevalence of HTE analyses and the statistical methods used to conduct them in CRTs focused on treating cardiovascular disease, cancer, and chronic lower respiratory diseases. Additionally, we also report on the proportion of CRTs that reported on baseline demographics of its populations and conducted demographic HTE analyses.

Data sources

We searched PubMed and Embase for CRTs published between 1/1/2010 and 3/29/2016 that focused on treating the top 3 Center for Disease Control causes of death (cardiovascular disease, chronic lower respiratory disease, and cancer).

Evidence Screening And Review: Of 1,682 unique titles, 117 abstracts were screened. After excluding 53 articles, we included 64 CRT publications and abstracted information on study characteristics and demographic information, statistical analysis, HTE analysis, and study quality.

Results

Age and sex were reported in greater than 95.3% of CRTs, while race and ethnicity were reported in only 20.3% of CRTs. HTE analyses were conducted in 28.1% (n = 18) of included CRTs and 77.8% (n = 12) were prespecified analyses. Four CRTs conducted a demographic subgroup analysis. Only 6/18 CRTs used interaction testing to determine whether HTE existed.

Conclusions

Baseline demographic reporting was high for age and sex in CRTs, but was uncommon for race and ethnicity. HTE analyses were uncommon and was rare for demographic subgroups, which limits the ability to examine the extent of benefits or risks for treatments tested with CRT designs.

Racial differences in long-term outcomes among black and white patients with drug-eluting stents

BACKGROUND

Some studies suggest that black patients may have worse outcomes after drug-eluting stent (DES) placement. There are limited data characterizing long-term outcomes by race. The objective was to compare long-term outcomes between black and white patients after percutaneous coronary intervention (PCI) with DES implantation.

METHODS

We analyzed 915 black and 3,559 white (n = 4,474) consecutive patients who underwent DES placement at Duke University Medical Center from 2005 through 2013. Over 6-year follow up, we compared rates of myocardial infarction (MI), all-cause mortality, revascularization, and major bleeding between black and white patients. A multivariable Cox regression model was fit to adjust for potentially confounding variables. Dual-antiplatelet therapy use over time was determined by patient follow-up surveys and compared by race.

RESULTS

Black patients were younger; were more often female; had higher body mass indexes; had more diabetes mellitus, hypertension, and renal disease; and had lower median household incomes than white patients (P < .001). At 6 years after DES placement, black relative to white patients had higher unadjusted rates of MI (12.1% vs 10.1%, hazard ratio 1.25, 95% CI 1.00-1.57, P = .05) and major bleeding (17.8% vs 14.3%, hazard ratio 1.28, 95% CI 1.07-1.54, P = .01), but there were no significant differences in other outcomes. After multivariable adjustment, there were no statistically significant racial differences in any of these outcomes at 6 years. Similarly, dual-antiplatelet therapy use was comparable between racial groups.

CONCLUSIONS

Unadjusted rates of MI and major bleeding over long-term follow up were higher among black patients compared to white patients, but these differences may be explained by racial differences in comorbid disease.

Exploring patient–provider decision-making for use of anticoagulation for stroke prevention in atrial fibrillation: Results of the INFORM-AF study

Background:

Atrial fibrillation is associated with stroke, yet approximately 50% of patients are not treated with guideline-directed oral anticoagulants (OACs).

Aims:

Given that the etiology of this gap in care is not well understood, we explored decision-making by patients and physicians regarding OAC use for stroke prevention in atrial fibrillation.

Methods and results:

We conducted a descriptive qualitative study among providers ( N=28) and their patients with atrial fibrillation for whom OACs were indicated ( N=25). We used purposive sampling across three outpatient settings in which atrial fibrillation patients are commonly managed: primary care ( n=14), geriatrics ( n=10), and cardiology ( n=4). Eligible patients were stratified by those prescribed OAC ( n=13) and not prescribed OAC ( n=12). Semi-structured, in-depth interviews assessed decision-making regarding risk and OAC use. Classical content analysis was used to code narratives and identify themes. Results among patients consisted of the overarching theme of trust in provider recommendations. Sub-themes included: awareness of increased risk of stroke with atrial fibrillation; willingness to accept medications recommended by their physician; and low demand for explanatory decision aids. Among physicians, the overarching theme was decisional conflict regarding the balance between stroke and bleeding risk, and the optimal medication to prescribe. Subthemes included: absence of decision aids for communication; and misperceptions around the assessment and management of stroke risk with atrial fibrillation.

Conclusions:

Patient involvement in decision-making around OAC use did not occur in this study of patients with atrial fibrillation. Improved access to decision aids may increase patient engagement in the decision-making process of OAC use for stroke prevention.