Utilization of cardiac resynchronization therapy in eligible patients hospitalized for heart failure and its association with patient outcomes

Gender Effect on Clinical Profiles, Pharmacological Treatments and Prognosis in Patients Hospitalized for Heart Failure

Heart failure (HF) is a significant disease affecting 1-2% of the general population. Despite its general aspects, HF, like other cardiovascular diseases, presents various gender-specific aspects in terms of etiology, hemodynamics, clinical characteristics, therapy, and outcomes. As is well known, HF with preserved ejection fraction more frequently affects females, with diabetes and arterial hypertension representing the most critical determinants of HF. On the other hand, women are traditionally underrepresented in clinical trials and are often considered undertreated. However, it is not clear whether such differences reflect cultural behaviors and clinical inertia or if they indicate different clinical profiles and the impact of sex on hard clinical outcomes. We aimed to review the sex-related differences in patients affected by HF.

Left ventricular lead implantation failure in an unselected nationwide cohort

BACKGROUND

Left ventricular (LV) lead implantation is often the most challenging aspect of cardiac resynchronization therapy (CRT) procedures; early studies reported implant failure rates in ∼10% of cases.

OBJECTIVE

The purpose of this study was to define rates, reasons for, and factors independently associated with LV lead implant failure.

METHODS

We studied patients with left bundle branch block and ejection fraction ≤ 35% who underwent planned de novo transvenous CRT implantation (2010-2016) and were reported to the National Cardiovascular Data Registry ICD Registry. Independent predictors of LV lead implant failure were determined using logistic regression; age, sex, and variables with a univariable P value of <.15 were considered for inclusion in the model.

RESULTS

Of the 111,802 patients who underwent a planned CRT procedure, 3.6% of patients (n = 3979) had LV lead implant failure. Reasons for implant failure included venous access (7.5%), coronary sinus access (64.3%), tributary vein access (13.5%), coronary sinus dissection (7.6%), unacceptable threshold (4.4%), and diaphragmatic stimulation (1.7%). Significant independent predictors of LV lead implant failure included younger age (odds ratio [OR] 1.01; 95% confidence interval [CI] 0.1.01-1.02), female sex (OR 1.38; 95% CI 1.29-1.47), black race (vs white, OR 1.44; 95% CI 1.32-1.57), Hispanic ethnicity (OR 1.23; 95% CI 1.08-1.40), QRS duration (OR 1.055 per 10 ms; 95% CI 1.038-1.072 per 10 ms), obstructive sleep apnea (OR 1.14; 95% CI 1.04-1.24), and implantation by a physician without specialized training (vs electrophysiology trained, OR 1.53; 95% CI 1.34-1.76).

CONCLUSION

LV lead implant failure is uncommon in the current era and is most commonly due to coronary sinus access failure. Predictors of LV lead implant failure included younger age, female sex, black race, Hispanic ethnicity, increased QRS duration, sleep apnea, and absence of electrophysiology training.

Recent successes in heart failure treatment

Remarkable recent advances have revolutionized the field of heart failure. Survival has improved among individuals with heart failure and a reduced ejection fraction and for the first time, new therapies have been shown to improve outcomes across the entire ejection fraction spectrum of heart failure. Great strides have been taken in the treatment of specific cardiomyopathies such as cardiac amyloidosis and hypertrophic cardiomyopathy, whereby conditions once considered incurable can now be effectively managed with novel genetic and molecular approaches. Yet there remain substantial residual unmet needs in heart failure. The translation of successful clinical trials to improved patient outcomes is limited by large gaps in implementation of care, widespread lack of disease awareness and poor understanding of the socioeconomic determinants of outcomes and how to address disparities. Ongoing clinical trials, advances in phenotype segmentation for precision medicine and the rise in technology solutions all offer hope for the future.

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.

Disparities in heart transplantation

PURPOSE OF REVIEW

Heart transplantation remains the gold standard therapy for end stage heart failure, but barriers remain, preventing equitable access to and affecting outcomes following transplantation. The objective of this review is to summarize current and historical literature on the disparities that persist, and to highlight the gaps in evidence for further investigation.

RECENT FINDINGS

Although progress has been made to increase the rates of advanced heart failure therapies to racial/ethnic minority populations and those with lower socioeconomic status, differential access and outcomes remain. The disparities that persist are categorized by patient demographics, social influences, geopolitical factors, and provider bias.

SUMMARY

Disparities in heart transplantation exist, which span a wide spectrum. Healthcare professionals need to be cognizant of these disparities that patients face in terms of access to and outcomes for heart transplantation. Further research and system changes are needed to make heart transplantation a fairer option for patients of varying backgrounds with end stage heart failure.

Utilization and Efficacy of Cardiac Resynchronization Therapy in Patients With Chronic Heart Failure ― A Report From the CHART-2 Study ―

Background: Although cardiac resynchronization therapy (CRT) is effective for patients with chronic heart failure (CHF) with reduced left ventricular ejection fraction and wide QRS (≥120 ms), data on the use of or long-term outcomes after CRT implantation in Japan are limited.

Methods and Results: We examined proper CRT utilization and outcomes in 3,447 consecutive symptomatic CHF patients registered in the CHART-2 Study. We identified 167 potentially eligible patients and divided them into 4 groups according to the presence (+) or absence (−) of an indication for and implantation of CRT: Group A (reference group), (+)indication/(+)CRT; Group B, (+)indication/(−)CRT; Group C, (−)indication/(+)CRT; and Group D, (−)indication/(−)CRT. Based on the Japanese Circulation Society guidelines, 91 patients met the eligibility for CRT implantation, with 43 (47%) of them undergoing CRT implantation. After adjusting for confounders, age was significantly associated with no CRT use (odds ratio per 5-year increase 1.46; 95% confidence interval 1.11–2.05; P=0.012). Among the 4 groups, the cumulative incidence of cardiovascular death and CHF admission were highest in Group B and lowest in Group D (P=0.029).

Conclusions: In this study, only half the eligible CHF patients properly received CRT. Aging was a significant risk factor for no CRT use. Patients without CRT despite having an indication could be at higher risk of mortality and CHF admission.

Guideline-directed device therapies in heart failure: A clinical practice-based analysis using electronic health record data

Background

Guideline-directed device therapies (GDDT) improve outcomes for eligible patients with heart failure (HF) with reduced ejection fraction (HFrEF). Utilization rates of device therapies in HFrEF after the 2012 ACCF/AHA/HRS Focused Update for Device-based Therapies of Cardiac Rhythm Abnormalities have not been well studied.

Objective

Characterize the use of GDDT in newly indicated HFrEF patients from 2012 to 2019 using aggregated electronic health record (EHR) data.

Methods

Computable phenotyping algorithms for implantable cardioverter defibrillator/cardiac resynchronization therapy-defibrillator (ICD/CRT-D) indications from the GuideLine Indications Detected in EHR for Heart Failure program (GLIDE-HF) used diagnoses, procedures, measures, prescriptions, and the output of natural language processed provider notes from de-identified Optum® EHR data. Patients had a diagnosis of HF, dilated cardiomyopathy, or prior infarct, and were included if they had HFrEF with >1 year of records prior to a new Class 1 or Class 2a indication for an ICD or cardiac resynchronization therapy with defibrillator (CRT-D) from 2012 to 2019.

Results

Records showed 137,476 HFrEF patients were newly indicated for an ICD or CRT-D. GDDT was used in 14,892 of 36,358 (41.0%) CRT-D indicated patients and in 14,904 of 101,118 (14.7%) ICD-indicated patients. While GDDT use was low, 95.7% had echocardiography and 92.1% had prescriptions for beta-blockers or angiotensin-converting enzyme/angiotensin-receptor blockers medications.

Conclusions

In this modern cohort of HF patients, a large proportion of eligible patients did not receive ICDs or CRT-Ds, while frequently receiving other indicated cardiovascular interventions and treatments.

Heart Failure Subtypes and Cardiomyopathies in Women

Heart failure affects over 2.6 million women and 3.4 million men in the United States with known sex differences in epidemiology, management, response to treatment, and outcomes across a wide spectrum of cardiomyopathies that include peripartum cardiomyopathy, hypertrophic cardiomyopathy, stress cardiomyopathy, cardiac amyloidosis, and sarcoidosis. Some of these sex-specific considerations are driven by the cellular effects of sex hormones on the renin-angiotensin-aldosterone system, endothelial response to injury, vascular aging, and left ventricular remodeling. Other sex differences are perpetuated by implicit bias leading to undertreatment and underrepresentation in clinical trials. The goal of this narrative review is to comprehensively examine the existing literature over the last decade regarding sex differences in various heart failure syndromes from pathophysiological insights to clinical practice.

Sex Differences in Heart Failure

Heart failure (HF) continues to be a major contributor of morbidity and mortality for men and women alike, yet how the predisposition for, course and management of HF differ between men and women remains underexplored. Sex differences in traditional risk factors as well as sex-specific risk factors influence the prevalence and manifestation of HF in unique ways. The pathophysiology of HF differs between men and women and may explain sex-specific differences in clinical presentation and diagnosis. This in turn contributes to variation in response to both pharmacologic and device/surgical therapy. This review examines sex-specific differences in HF spanning prevalence, risk factors, pathophysiology, presentation, and therapies with a specific focus on highlighting gaps in knowledge with calls to action for future research efforts.

Sex differences in CRT device implantation rates, efficacy, and complications following implantation: protocol for a systematic review and meta-analysis of cohort studies

INTRODUCTION

There is abundant evidence for sex differences in the diagnosis, implantation, and outcomes for cardiac resynchronization therapy (CRT) devices. Controversial data suggesting women are less likely to receive the device regardless of the greater benefit. The aim of this review is to assess sex differences in the implantation rate, clinical effectiveness, and safety of patients receiving CRT devices.

METHODS

We will conduct a systematic literature search of MEDLINE, Embase, and Web of Science to identify cohort studies that meet our eligibility criteria. Title and full text screening will be conducted in duplicate independently. Eligible studies report clinical effectiveness or safety of patients receiving CRT device while providing sex-disaggregated data. Implantation rate will be extracted from the baseline characteristics tables of the studies. The effectiveness outcomes include the following: all-cause death, hospitalization, peak oxygen consumption (pVO₂), quality of life (QoL), 6-min walk test, NYHA class reduction, LVEF, and heart failure hospitalization. The complication outcomes include the following: contrast-induced nephropathy, pneumothorax, pocket-related hematoma, pericardial tamponade, phrenic nerve stimulation, device infection, death, pulmonary edema, electrical storm, cardiogenic shock, and hypotension requiring resuscitation. Description of included studies will be reported in detail and outcomes will be meta-analyzed and presented using forest plots when feasible. Risk of bias will be assessed using the Newcastle-Ottawa Scale (NOS) by two review authors independently. GRADE approach will be used to assess the certainty of evidence.

DISCUSSION

The aim of this review is to determine the presence of differences in CRT implantation between women and men as well as differences in clinical effectiveness and safety of CRT after device implantation. Results from this systematic review will provide important insights into sex differences in CRT devices that could contribute to the development of sex-specific recommendations and inform policy.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020204804.

The Lancet women and cardiovascular disease Commission: reducing the global burden by 2030

Cardiovascular disease is the leading cause of death in women. Decades of grassroots campaigns have helped to raise awareness about the impact of cardiovascular disease in women, and positive changes affecting women and their health have gained momentum. Despite these efforts, there has been stagnation in the overall reduction of cardiovascular disease burden for women in the past decade. Cardiovascular disease in women remains understudied, under-recognised, underdiagnosed, and undertreated. This Commission summarises existing evidence and identifies knowledge gaps in research, prevention, treatment, and access to care for women. Recommendations from an international team of experts and leaders in the field have been generated with a clear focus to reduce the global burden of cardiovascular disease in women by 2030. This Commission represents the first effort of its kind to connect stakeholders, to ignite global awareness of sex-related and gender-related disparities in cardiovascular disease, and to provide a springboard for future research.

Racial/Ethnic and Gender Disparities in Heart Failure with Reduced Ejection Fraction

PURPOSE OF REVIEW

This review highlights variability in prescribing of nonpharmacologic heart failure with reduced ejection fraction (HFrEF) therapies by race, ethnicity, and gender. The review also explores the evidence underlying these inequalities as well as potential mitigation strategies.

RECENT FINDINGS

There have been major advances in HF therapies that have led to improved overall survival of HF patients. However, racial and ethnic groups of color and women have not received equitable access to these therapies. Patients of color and women are less likely to receive nonpharmacologic therapies for HFrEF than White patients and men. Therapies including exercise rehabilitation, percutaneous transcatheter mitral valve repair, cardiac resynchronization therapy, heart transplant, and ventricular assist devices all have proven efficacy in patients of color and women but remain underprescribed. Outcomes with most nonpharmacologic therapy are similar or better among patients of color and women than White patients and men. System-level changes are urgently needed to achieve equity in access to nonpharmacologic HFrEF therapies by race, ethnicity, and gender.

Impact of Guidelines on the Diffusion of Medical Technology: A Case Study of Cardiac Resynchronization Therapy in the UK

INTRODUCTION

Research on clinical practice guidelines as a determinant of the diffusion of medical technology remains sparse. We aim to evaluate the impact of guidelines on the awareness of medical technology, as a proxy of its use, with the example of cardiac resynchronization therapy (CRT) in the United Kingdom (UK).

METHODS

We measured clinician awareness based on Google searches performed for CRT that corresponded with actual CRT implant numbers provided by the European Heart Rhythm Association (EHRA). We identified the guideline recommendations published by the National Institute of Health and Care Excellence (NICE) within the UK, the European Society of Cardiology (ESC) at the European level, and the American College of Cardiology Foundation/American Heart Association in the United States (US). We specified a dynamic moving average model, with Google searches as the dependent variable and guideline changes as the independent variables.

RESULTS

One guideline change published by NICE in 2007 and two changes released by the US guidelines in 2005 and 2012 were significantly correlated with the Google searches (p = 0.08, p = 0.02, and p = 0.02, respectively). Guideline changes by the ESC had no significant impact. Changes recommending CRT in place of a conventional pacemaker, in patients with atrial fibrillation, and restricting CRT due to contraindication, remained universally uninfluential.

CONCLUSION

The factors associated with a lack of awareness (as a proxy for technology diffusion) in our case study were: a lack of strong clinical evidence that resulted in the moderate strength of a recommendation, a lack of recognition of any externally published recommendation by NICE, and the frequent release of guidelines with minor changes targeting small patient groups. At least in our case, in the absence of NICE guidelines, the US guidelines received more attention than their non-UK European counterparts, even if the former were released after the latter.

A Qualitative Analysis of Patient-Related Factors Associated With Implantable Cardioverter Defibrillator Acceptance

INTRODUCTION

Patient-related factors determining implantable cardioverter-defibrillator (ICD) use for primary prevention of sudden cardiac death in patients with cardiomyopathy have not been well explored. To assess race and sex differences regarding ICD preferences in this patient population, we sought to analyze a diverse cohort of patients with heart failure (HF) with reduced ejection fraction.

METHODS

We conducted qualitative interviews of 28 adults with severe HF and either (1) an ICD or (2) no ICD. Interviews were recorded, transcribed, and coded using an inductively developed codebook by independent investigators. Coding was fully adjudicated and transcripts were reviewed to identify themes.

RESULTS

We recruited patients between 12/2015 and 06/2017, primarily from the outpatient cardiology clinic (24/28 = 86%). Half were women (50%) and 13/28 (46%) were black. Eight did not have an ICD. Neither race nor sex was associated with ICD. Four themes emerged: (1) HF requiring an ICD is profoundly disruptive to patients' lives; (2) patients had positive, yet unrealistic opinions of ICDs; or (3) Patients had negative/ambivalent opinions of ICDs; (4) medical decision-making included aspects of shared decision-making and informed consent.

CONCLUSIONS

Patients without ICDs perceived less benefit from ICDs and had less decision support. Participants viewed conversations with providers as insufficient. Needed interventions include the development and validation of processes for informed decisions about ICDs.

Sex differences in eligibility for advanced heart failure therapies

OBJECTIVES

We investigated sex-based differences in eligibility for and outcomes after receipt of advanced heart failure (HF) therapies.

BACKGROUND

Although women are more likely to die from HF than men, registry data suggest that women are less likely to receive heart transplant (HT) or left ventricular assist device (LVAD) for largely unknown reasons.

METHODS

We performed a single-center retrospective cohort study of patients evaluated for advanced HF therapies from 2012 to 2016. Logistic regression was used to determine the association of sex with eligibility for HT/LVAD. Competing risks and Kaplan-Meier analysis were used to examine survival.

RESULTS

Of 569 patients (31% women) evaluated, 223 (39.2%) were listed for HT and 81 (14.2%) received destination (DT) LVAD. Women were less likely to be listed for HT (adjusted odds ratio [OR] 0.36, 95% confidence interval [CI] 0.21-0.61; P < .0001), based on allosensitization (P < .0001) and obesity (P = .02). Women were more likely to receive DT LVAD (adjusted OR 2.29, 95% CI 1.23-4.29; P = .01). Survival was similar between men and women regardless of whether they received HT and DT LVAD or were ineligible for therapy.

CONCLUSION

Women are less likely to be HT candidates, but more likely to receive DT LVAD.

Sex Differences in Advanced Heart Failure Therapies

This in-depth review of sex differences in advanced heart failure therapy summarizes the existing literature on implantable cardioverter defibrillators, biventricular pacemakers, mechanical circulatory support, and transplantation with a focus on utilization, efficacy/clinical effectiveness, adverse events, and controversies. One will learn about the controversies regarding efficacy/clinical effectiveness of implantable cardioverter defibrillators and understand why these devices should be implanted in women even if there are sex differences in appropriate shocks. Individuals will learn about the sex differences with biventricular pacemakers with respect to ventricular remodeling and reduction in heart failure hospitalizations/mortality, as well as, possible mechanisms. We will demonstrate sex differences in heart transplantation and waitlist survival. Despite similar survival for women and men with left ventricular assist devices, there are sex differences in adverse events. These devices do successfully bridge women and men to transplant, yet women are less likely than men to have a left ventricular assist at time of listing and time of transplantation. Finally, one will learn about the concerns regarding poor outcome for men who receive female donor hearts and discover this may not be due to sex, but rather size. More research is needed to better understand sex differences and further improve advanced heart failure therapy for both women and men.

Implantable Cardioverter-Defibrillators and Cardiac Resynchronization Therapy in Women

Implantable cardioverter-defibrillator and cardiac resynchronization therapy devices have been prescribed for patients with heart failure for several decades. Factors leading to increased usage include significant enhancements in technology and availability of multiple randomized clinical trials demonstrating their benefit with improved implementation of evidence-based guidelines. Despite these advances, gaps still exist in the utilization and referral of these devices, particularly among women. This article reviews the literature on these devices with a focus on gender differences and proposes reasons for why they exist.

The Past, Present and Future of Cardiac Resynchronization Therapy

Cardiac resynchronization therapy (CRT) has revolutionized the care of the patients with heart failure with reduced ejection fraction and electrical dyssynchrony. The current guidelines for patient selection include measurement of left ventricular systolic function, QRS duration and morphology, and functional classification. Despite consistent and increasing evidence supporting CRT use in appropriate patients, CRT has been underutilized. Notwithstanding the heterogeneous definitions of non-response, more than one-third of patients demonstrate a lack of echocardiographic reverse remodeling or poor clinical outcome following CRT. Since the causes of this non-response are multifactorial, it will require multidisciplinary efforts to overcome including optimal patient selection, procedural strategies, as well as optimizing post-implant care in patients undergoing CRT. The innovations of novel pacing approaches combined with advanced imaging technologies may eventually offer a personalized CRT system uniquely tailored to each patient's dyssynchrony signature.

Persistent sex disparities in implantable cardioverter-defibrillator therapy

BACKGROUND

Clinical guidelines recommend cardioverter defibrillator implantation for patients with heart failure and reduced ejection fraction. Despite this, women and minorities have been less likely to receive implantable cardioverter-defibrillator (ICD) therapy than white men. We examined race and sex differences in ICD implantation in a recent cohort.

METHODS

Using cross-sectional, retrospective analyses, we mined our health system's outpatient electronic medical records to assess age, race, sex, medications, and comorbidities for patients aged ≥18 years with ejection fraction ≤ 35% during 2014. While adjusting for confounding variables such as medications, age, and comorbidities, we conducted a multivariable logistic regression assessing whether racial and sex differences in ICD therapy persist.

RESULTS

Among 5,156 outpatients with ejection fraction ≤35%, 1,681 (32.6%) patients had an ICD present at the time of their index outpatient visit in 2014. Women were less likely to have an ICD than men (25.0% vs 36.3%, P < 0.01), and black patients were less likely to have an ICD than white patients (28.0% vs 33.2%, P  =  0.02). In adjusted multivariable analyses, women were less like to have ICDs (adjusted odds ratio [OR]  =  0.68, 95% confidence interval [CI], 0.58-0.79, P < 0.01) but the race difference dissipated (adjusted OR for black race  =  0.86, 95% CI, 0.68-1.08, P  =  0.18).

CONCLUSIONS

In this large, outpatient cohort, we have shown that sex differences in ICD therapy continue to exist, but the difference in ICD prevalence by race was attenuated. Dedicated studies are required to fully understand the causes of persistent sex differences in ICD therapy.

Physical Training and Cardiac Rehabilitation in Heart Failure Patients

Regardless of advances in medical and interventional treatment of cardiovascular disease (CVD), a limited number of patients attend a cardiac rehabilitation (CR) programme on a regular basis. Due to modern therapies more individuals will be surviving an acute cardiovascular event, but the expected burden of chronic heart failure will be increasing worldwide.However, both in high- and low-income countries, secondary prevention after an acute myocardial infarction or stroke has been implemented in less than a half of eligible patients.Combined interventions are still needed to reduce decompensations, hospitalizations and mortality in heart failure patients from any origin. In addition to medical treatments, regular exercise has been demonstrated to improve metabolic and hemodynamic conditions in both asymptomatic risk factor carriers and cardiac patients. Risk factor control and exercise should gather together for an effective management of patients.Exercise-based training is a core component of primary and secondary prevention. It should involve healthy carriers of cardiovascular risk factors, and patients with cardiomyopathy as well. The supposed attenuated effect of CR in the era of advanced revascularization and structural interventions is due to the heterogeneity of training models and physical training in the literature. Moreover, lifestyle modification, psycho-social challenges and patient's compliance are potential confounders.In this chapter the most recent evidences about training modalities and potential benefit of CR in heart failure patients are discussed.