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. Author manuscript; available in PMC: 2024 Oct 1.
Published in final edited form as: JACC Heart Fail. 2023 Jun 28;11(10):1397–1407. doi: 10.1016/j.jchf.2023.05.017

Racial and Ethnic Disparities in Ambulatory Heart Failure Ventricular Assist Device Implantation and Survival

Debra D Dixon a, Shannon M Knapp b, Onyedika Ilonze c, Sabra C Lewsey d, Sula Mazimba e, Selma Mohammed f, Harriette GC Van Spall g, Khadijah Breathett c
PMCID: PMC10614028  NIHMSID: NIHMS1936800  PMID: 37389504

Abstract

Background:

Durable left ventricular assist devices (VADs) improve survival in eligible patients, but allocation has been associated with patient race in addition to presumed heart failure (HF) severity.

Objective:

To determine racial and ethnic differences in VAD implantation rates and post-VAD survival among patients with ambulatory HF.

Methods:

Using the INTERMACS database (2012–2017), we examined census-adjusted VAD implantation rates by race, ethnicity, and sex in patients with ambulatory HF (INTERMACS profile 4–7) using negative binomial models with quadratic effect of time. Survival was evaluated using Kaplan-Meier estimates and Cox models adjusted for clinically relevant variables and an interaction of time with race/ethnicity.

Results:

VADs were implanted in 2,256 patients with ambulatory HF (78.3% White, 16.4% Black, and 5.3% Hispanic adults, respectively). Median age at implantation was lowest in Black patients. Implantation rates peaked between 2013–2015 before declining in all demographic groups. From 2012–2017, implantation rates overlapped for Black and White patients but were lower for Hispanic patients. Post-VAD survival was significantly different among the three groups (log rank p-value=0.0067), with higher estimated survival among Black vs. White patients [12-month survival: Black patients 90%(95%CI:86–93%); White patients 82%(95%CI:80–84%)]. Low sample size for Hispanic patients resulted in imprecise survival estimates [12-month survival: 85%(95%CI:76–90%)].

Conclusions:

Black and White patients with ambulatory HF had similar VAD implantation rates but rates were lower for Hispanic patients. Survival differed among the three groups, with the highest estimated survival at 12 months in Black patients. Given higher HF burden in minoritized populations, further investigation is needed to understand differences in VAD implantation rates in Black and Hispanic patients.

Keywords: Ventricular assist device, racial disparities, health disparities, heart failure, INTERMACS profile, ambulatory heart failure

INTRODUCTION

Durable mechanical circulatory support with ventricular assist devices (VAD) has been shown to improve survival and quality of life in patients with advanced heart failure (HF).(1) However, the majority of VADs are implanted in patients with Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) Profiles 1–3.(2) Initial studies suggest that patients with ambulatory HF, defined by INTERMACS Profiles 4–7, may benefit from VAD implantation. In the ROADMAP study, early VAD implantation in patients with ambulatory HF was associated with improvement in a composite endpoint of survival and 6-minute walk distance and with increased quality of life, compared to optimal medical management.(3) In the Medical Arm of Mechanically Assisted Circulatory Support (MedaMACS) study, a combined group of patients with INTERMACS profiles 4 and 5 had improved survival with VAD compared to medical management.(4) Given the potential benefit of timely allocation of VADs among eligible patients with advanced HF, further characterization of VAD implantation rates in the population with ambulatory HF is needed.

VAD implantation rates in the United States are characterized by racial and ethnic disparities. In prior work, we have shown that VAD implantation rates have increased in Black patients in possible relation to health insurance expansion, but there is still underutilization given the high prevalence of HF in minoritized racial and ethnic groups compared to their White counterparts.(5) Interestingly, the increase seen in Black patients differed by sex, with the greatest increase in implantation rates noted in Black men.(5) However, VAD implantation rates in patients with ambulatory HF and differences by race and ethnicity remain poorly understood. Decisions regarding allocation of advanced HF therapies have been demonstrated to be influenced by race and sex-based biases and a propensity of clinicians to incorrectly presume higher acuity illness in Black male patients.(6,7) Post-VAD survival outcomes are better in patients with ambulatory HF compared to INTERMACS profiles 1–3, and thus timing of VAD implantation, in addition to allocation decisions, may contribute to disparities in HF outcomes among minoritized racial and ethnic groups. (8,9)

In this study, we sought to determine the trends in VAD implantation and survival rates from 2012 to 2017 for White, Black, and Hispanic patients with ambulatory HF using the INTERMACS registry and US Census data. Given important differences in HF by sex, we also evaluated trends in implantation rates by sex. We hypothesized that VAD implantation rates would be higher among White patients than Black and Hispanic patients and that survival post-VAD would be similar across groups. Understanding the differences in rates of VAD implantation in those with ambulatory HF by race, ethnicity, and sex may identify care gaps contributing to health inequities that can serve as targets for further investigation and intervention.

METHODS

Data Source

The INTERMACS registry is comprised of quarterly data collected from patients receiving durable VADs for HF.(10) Data is entered for individual patients by participating centers with institutional review board approval and informed consent from patients. Additional INTERMACS registry details are available in the Supplemental Materials. The IRB at the University of Arizona deemed this study exempt from human subjects review as the data is deidentified and publicly available.

Study Cohort

This cohort includes 2,256 individuals meeting the following criteria: 1) adult aged ≥ 19 years, 2) received a VAD at a participating INTERMACS registry center from 2012–2017, 3) ambulatory HF defined as an INTERMACS profile 4–7, and 4) listed race of Black or White and/or Hispanic ethnicity. Other races and ethnicities were excluded from the cohort due to low representation. Observations with incomplete or inconsistent outcome data were also excluded (n=24) to yield the final cohort of 2,256 individuals.

Outcomes of Interest

The primary outcome was the census-adjusted rate of VAD implantation. VAD implantation rates were compared by race and ethnicity with a secondary analysis by sex. The secondary outcome was 12-month survival free of disabling stroke following VAD implantation. Disabling stroke was defined as moderate or greater on the NIH Stroke Scale.(11)

Demographic and clinical factors

Demographic information including age, sex, race, ethnicity, highest education level, and working for income were collected at enrollment into the INTERMACS database. Details regarding height, weight, device strategy, primary cardiac diagnosis, comorbidities, intravenous inotrope support, and clinical events and interventions prior to implantation were collected as close as possible to VAD implantation (not to exceed 60 days). Laboratory values for creatinine, hemoglobin, and platelets were reported representing the last values available prior to implant in the patient’s medical record. Laboratory values for creatinine, hemoglobin, and platelets are anticipated to be within 48 hours of implantation and are not to exceed 60 days prior to implantation. The INTERMACS profile is determined and assigned according to the INTERMACS Patient Profile rubric (Appendix O).(11)

Statistical Analysis

Patient characteristics are reported as count and percent or median and interquartile range as appropriate. A negative binomial model was fit to the number of VAD implantations by race, ethnicity, and quarter. The model included race, a quadratic effect of time, and an offset of population size to return census-adjusted rates of implantation. A second model was fit to counts of implantation by race and sex for Black and White patients in addition to the effects included in the first model. Hispanic patients were excluded from the secondary analysis as quarterly counts were too low for Hispanic patients when stratified by sex.

Population sizes for each race and ethnicity (and sex, for the second model) were derived from annual US Census estimates for 2011 to 2018. The annual estimates were as of July 1st each year and, thus treated as the value for the midpoint of the year (e.g., the 2014 census estimate was treated as the population size at year = 2014.5). Time points for each quarter were treated as being at the midpoint of each quarter (e.g., for 2014 the time for the four quarters would be 2014.125, 2014.375, 2014.625, and 2014.875). Population size for each quarter was estimated via linear interpolation between the nearest two adjacent points. Census estimates included only adults age ≥ 19.

Stroke-free survival was evaluated via Kaplan-Meier estimates and Cox proportional hazards models. Observations were censored at the time of transplant or explant. Those still alive and stroke-free at 12 months were censored at 12 months. Cox models were adjusted for age (< 60 vs. ≥ 60), sex, device strategy (destination vs. all other strategies), prior cardiac surgery, body mass index (BMI; < 30 vs. ≥ 30), INTERMACS profile, creatinine, hemoglobin, and platelet count. An interaction of time with race/ethnicity was also included in the model to account for non-proportionality of the hazards. For the Cox model, 33 (1.46%) observations had missing values of 1 or more predictors (BMI n=16, creatinine n=8, hemoglobin n=15, and platelet count n=12), so multiple imputation was done via fully conditional specification (FCS) methods in SAS PROC MI using logistic regression for BMI (< 30 vs. ≥ 30) and predictive mean modeling for the three continuous variables (creatinine, hemoglobin, and platelet count). As a sensitivity analysis, stroke-free survival was also assessed for patients <60 years of age using the same analyses with the exception of adjusting for age.

Analyses were performed using SAS, version 9.4 (SAS Institute, Inc, Cary, NC) and R statistical software (R version 4.2.2; Foundation for Statistical Computing, Vienna, Austria).

RESULTS

Patient characteristics

From 2012 to 2017, 2,256 patients with ambulatory HF (78.3% White, 16.4% Black, and 5.3% Hispanic patients, respectively) received a VAD (Table 1). The median age of VAD implantation was lowest in Black patients at 56 years with the majority of VAD implantations in White and Hispanic patients occurring in those age 60 or older. Women received less than half of the VADs (White women 16%, Black women 38%, Hispanic women 19%). Dilated cardiomyopathy was the most common etiology of HF. White patients underwent VAD implantation most commonly as a destination strategy. INTERMACS profiles 4 and 5 were most common among all racial and ethnic groups. Prior cardiac surgery was more common in White and Hispanic patients than in Black patients. There was a low prevalence (<5%) of pulmonary disease and severe diabetes among all groups. Intravenous inotropes and a BMI ≥ 30 were most common in Black patients. Rates of active smoking were similar in White and Black patients with no active smoking reported in Hispanic patients.

Table 1.

Characteristics of Patients with INTERMACS Profile 4–7 from 2012–2017

Characteristic White
(N=1767)		 Black
(N=370)		 Hispanic
(N=119)
Agea 64 (56, 70) 56 (45, 62) 60 (50, 68)
Sex
 Women 277 (15.7) 139 (37.6) 23 (19.3)
Primary Diagnosis
 CAD 100 (5.7) 8 (2.2) 3 (2.5)
 Dilated 1586 (89.8) 343 (92.7) 106 (89.1)
 Hypertrophic 15 (0.8) 4 (1.1) 2 (1.7)
 Restrictive 26 (1.5) 8 (2.2) 3 (2.5)
 Valvular 17 (1.0) 1 (0.3) 3 (2.5)
 Congenital 9 (0.5) 1 (0.3) 1 (0.8)
 Other 14 (0.8) 5 (1.4) 1 (0.8)
Device Strategy
 Destination 917 (51.9) 179 (48.4) 52 (43.7)
 Other 850 (48.1) 191 (51.6) 67 (56.3)
INTERMACS Profile
 4 1420 (80.4) 314 (84.9) 90 (75.6)
 5 238 (13.5) 37 (10.0) 17 (14.3)
 6 71 (4.0) 8 (2.2) 6 (5.0)
 7 38 (2.2) 11 (3.0) 6 (5.0)
Prior cardiac surgery 758 (42.9) 82 (22.2) 49 (41.2)
Pulmonary disease 66 (3.7) 13 (3.5) 1 (0.8)
Severe Diabetes 75 (4.2) 8 (2.2) 5 (4.2)
Intravenous Inotropes 491 (27.8) 128 (34.6) 26 (21.8)
BMI ≥ 30 747 (42.3) 179 (48.4) 49 (41.2)
Current smoker 77 (4.4) 17 (4.6) 0 (0)
Former smokerb 109 (6.2) 29 (7.8) 2 (1.7)
Laboratory Values
 Creatinine, mg/dLa 1.2 (1.0, 1.5) 1.3 (1.0, 1.6) 1.1 (0.9,1.4)
 Hemoglobin, g/dLab 12.3 (11.0,13.6) 11.9 (10.5, 13.0) 11.9 (10.1, 13.1)
 Platelets, x103/uLab 184 (148, 228) 196 (157, 242) 189 (156, 248)
Education Levelb
 None 2 (0.1) 1 (0.3) 2 (1.7)
 Grade School 27 (1.5) 3 (0.8) 14 (11.8)
 High School 527 (29.8) 134 (36.2) 38 (31.9)
 Any College 582 (33.0) 124 (33.5) 29 (24.4)
 Post College Graduate Degree 117 (6.6) 15 (4.1) 3 (2.5)
Working for Incomeb 252 (14.3) 44 (11.9) 10 (8.4)
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BMI, body mass index; CAD, coronary artery disease; IQR, interquartile range

a

Indicates continuous variables by median and IQR range. Categorial variables are represented by count and percent.

b

Indicates missing observations >2%. All other variables have <2% missing observations. Full details depicted in Supplemental Table 1.

Outcomes

Census-adjusted VAD implantation rates in patients with ambulatory HF peaked between 2013 and 2015 before declining in all populations (Figure 1, Central Illustration). From 2012 to 2017, implantation rates overlapped for Black and White patients; however, implantation rates were lower for Hispanic patients compared to Black and White patients. Stratified by sex, estimated implantation rates were generally higher in Black women compared to White women, but there was a general tendency for rates to decrease over time (Figure 2). In men, implantation rates were similar. Hispanic patients were excluded from this subgroup analysis due to low sample size.

Figure 1. VAD Implantation Rates From 2012 Through 2017 For Black, White, And Hispanic Patients With Ambulatory Heart Failure.

Figure 1.

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Census-adjusted VAD implantation rates are shown per 100,000 by race and ethnicity. Observed values are indicated by points; predicted values, curves; bands, 95% confidence intervals. White patients are represented in red, Black patients are represented in blue, and Hispanic patients are represented in green.

Central Illustration.

Central Illustration

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Trend In VAD Implantation Rates And 12-month Survival Estimates Among Patients with Ambulatory HF.

Figure 2. VAD Implantation Rates By Sex For Black And White Patients With Ambulatory Heart Failure.

Figure 2.

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Census-adjusted VAD implantation rates are shown per 100,000 by sex, race, and ethnicity. Observed values are indicated by points; predicted values, curves; bands, 95% confidence intervals. White patients are represented in red and Black patients are represented in blue.

Post-VAD survival was significantly different among the three groups (log rank test, p-value=0.0067, Figure 3, Supplemental Figure 1, Central Illustration). Estimated survival among Black patients was higher than among White patients by 12 months (12-month survival: Black 90% [95% CI: 86–93%]; White 82% [95% CI: 80–84%]). Low sample size for Hispanic patients resulted in imprecise survival estimates (12-month survival 85% [95% CI 76–90%]). Cox models evaluating risk of death demonstrated that hazard ratios (HR) for Black vs. White patients declined over time, with HR less than 1 by 4 months (Figure 4, Supplemental Figure 2). The HR for Hispanic vs. White patients also appeared to decline over time; however, the small sample size of Hispanic patients resulted in imprecise estimates.

Figure 3. VAD Post-Implantation Survival Rates By Race and Ethnicity.

Figure 3.

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Bands represent 95% confidence intervals. White patients are represented in red, Black patients are represented in blue, and Hispanic patients are represented in green.

Figure 4. Risk Of Death Following VAD Implantation For Black And Hispanic Patients Compared To White Patients.

Figure 4.

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Cox models were adjusted for age, sex, device strategy, prior cardiac surgery, body mass index, INTERMACS profile, creatinine, hemoglobin, and platelet count. Bands represent 95% confidence intervals. Hazard ratio for Black versus White patients is represented in blue and Hispanic versus White patients are represented in green.

We performed a sensitivity analysis in patients aged less than 60 years old. Post-VAD survival remained significantly different among the three groups (log rank test, p-value =0.037; Supplemental Figure 3A and 3B). Estimated survival among Black patients was higher than among White patients by 12 months (12-month survival: Black 93% [95% CI:89–96%]; White 87% [95% CI: 84–90%]). Estimated 12-month survival in Hispanic patients was imprecise (84% [95% CI: 71–91%]). Similar to the full cohort, Cox models evaluating risk of death demonstrated that HR for Black vs. White patients declined over time, with HR less than 1 by 4 months (Supplemental Figure 4A and 4B). The HR for Hispanic vs. White patients also appeared to decline over time, but the estimates were also imprecise due to low sample size.

DISCUSSION

In this study using the INTERMACS database, VAD implantation rates in Black and White patients with ambulatory HF were similar, albeit higher than rates in Hispanic patients from 2012 to 2017. When stratified by sex, estimated rates were similar for men but higher implantation rates were generally seen in Black women compared to White women for the majority of the study period. Survival was significantly different among the three groups. Estimated survival was higher for Black patients with ambulatory HF compared to White patients. Overall, 12-month survival post-VAD was high, and risk of death declined over time.

The incidence and prevalence of HF is generally higher in Black and Hispanic individuals compared to White individuals.(12,13) In 2012, the age adjusted HF discharge rate per 100,000 was reported as 875 in Black men, 663 in Black women, 376 in White men, 270 in White women, 378 in Hispanic men, and 295 in Hispanic women.(14) A subsequent study through 2016 showed persistence in disparities in the age-standardized prevalence of HF with higher prevalence in Black adults.(15) In prior work in patients with advanced HF at all INTERMACS levels, we demonstrated per capita VAD implantation rates in 2012 were 2.01 for Black patients (514 VAD implantations) and 1.09 for White patients (1621 VADs).(5) Despite the implantation rate in Black patients being almost double that for White patients, this does not keep pace with the higher HF rate in Black patients. In this cohort of patients with ambulatory HF, the similar rates of VAD implantation between Black and White patients and reduced rates of implantation in Hispanic patients represent lower than expected VAD implantation rates for the burden of disease in Black and Hispanic patients and may suggest a larger racial and ethnic disparity in the population with ambulatory HF.

HF is diagnosed at an earlier age in Black patients, which is consistent with the lower median age of VAD implantation among Black patients in this cohort.(16) HF death rates are higher in Black men and women than both White men and women combined before the age of 65, which suggests that advanced therapy implantation rates should be higher in Black men and women than both White men and women.(17,18) However, women are less likely to receive advanced HF therapies, and represented less than half of VAD implants during this time period.(5,19,20) National studies spanning our study period report that Black women had the highest (2011–2014) or second highest (2015–2018) prevalence of HF.(13,21) In our study, Black women also had higher VAD implantation rates compared to White women but not White men. Women have higher rates of HF with preserved ejection fraction which may account, in part, for the differences between men and women, but sex-based bias remains an important factor in allocation, particularly since Black women have similar hospitalization rates of HF with preserved ejection fraction as HF with reduced ejection fraction.(7,22)

Survival was high overall in this cohort with estimated 12-month survival ≥ 82% in all groups. This rate is similar to 12-month survival rates in two prior studies of patients with ambulatory HF, including the ROADMAP study, but lower than the 95% 12-month survival reported in another study of similar INTERMACS profiles.(3,8,9) Differences in survival may be attributable to differences in selection criteria and VAD technology. When compared to post-implantation survival in patients with INTERMACS profiles 1–3 from 2015 to 2019, patients with profiles 4–7 have improved survival compared to profile 1 and 2 but similar survival to profile 3.(2) Historically, survival rates post-implantation for minoritized racial and ethnic groups, particularly Black patients, are similar to White patients.(23)

Among patients with ambulatory HF, this study found post-implantation survival was highest among Black patients, which may be attributable to lower median age at implantation. In a sensitivity analysis for patients aged less than 60 in this cohort, a statistically significant difference in survival persisted among the three groups. Survival estimates were higher in this younger population for Black and White patients and survival remained the highest among Black patients. Although the median age [IQR] at implantation was still lowest in Black patients (49 [41,56], 50 [43,55], and 53 [46,57] for Black, Hispanic, and White patients respectively), other potential reasons for higher survival in Black patients include clinical decision making, structural discrimination, and bias. Recent work has shown that among patients for whom the clinical benefit of VAD is less definitive (e.g., patients with ambulatory HF), there was significantly reduced use of VAD in Black patients but also improved survival at 1-year compared to their White counterparts, which is consistent with the findings of our study.(24) If clinical and socioeconomic profiles are accounted for between Black and White patients, one would expect survival rates to be similar. The reported differences in survival outcomes despite adjustment for clinical factors and social determinants of health, suggests that unmeasured factors in the allocation process (e.g., subjectivity, bias, and discrimination) may also play a role. (6,7,24) Indeed, racial and gender bias and discrimination may impact the timing and selection of advanced therapies across the HF severity spectrum, ultimately resulting in worse outcomes when delayed to higher acuity INTERMACS profiles.(6,7) In addition, data from the REVIVAL study demonstrated lower utilization of VAD and transplant in Black compared to White patients despite similar care preferences, suggesting discrimination and bias may be contributing factors.(25)

The present study enriches the current knowledge of VAD implantation rates in patients with ambulatory HF by utilizing a large, nationally representative, and multi-center dataset. The findings highlight disparities in VAD allocation by race, ethnicity, and sex in the population with ambulatory HF. Moreover, it suggests that differences in outcomes in Black and Hispanic patients may be explained, in part, by timing of advanced therapy initiation, particularly in the context of the findings of improved survival with VAD implantation in patients with ambulatory HF in the ROADMAP and MedaMACS studies.

With a better understanding of broad trends in VAD implantation rates in patients with ambulatory HF, the findings of this study highlight several areas for further investigation: elucidating patterns of referral for advanced HF patients, understanding the role of patient-level factors in the decision-making process, and addressing biases in the committee decision process, especially for subjective eligibility criteria. First, referral patterns for advanced HF therapies may differ by race, ethnicity and sex and are not well characterized. Black patients are less likely to receive care by a cardiologist when admitted to the ICU for HF which may have important implications for follow-up care and HF management.(26) Understanding the clinical decision-making process around referral and exploring potential biases is needed. National studies have revealed that bias may contribute to allocation of advanced therapies by race and sex, and the allocation process may be associated with the group dynamics of the multi-disciplinary decision-making team.(6,7,27) The recent scientific statement provides further guidance for referral of patients with advanced HF and outlines a 2-step process and framework to promote timely and appropriate referral.(28) Assessment of the integration of this process into clinical practice and the evaluation of strategies to promote implementation are opportunities for further investigation. Additionally, health insurance and access to care plays an important role in eligibility and referral for advanced therapies. Regional variation in health insurance with expansion/non-expansion of Medicaid under the Affordable Care Act as well as changes in transplant allocation policy should be examined to evaluate impact on advanced therapy referral and access.

Second, a deeper understanding is needed regarding how patient-level factors, such as health literacy and education, may impact the patient’s decision-making process. Although a combined group of patients with INTERMACS profiles 4 and 5 had improved survival compared to medical management, VAD implantation has not been demonstrated to have a definitive mortality benefit in the population with ambulatory HF.(4) Given the high prevalence and severity of complications related to VAD implantation, a thorough discussion and consideration of the risks and benefits for the individual patient are needed during the decision-making process.(29) The quality of education provided and the health literacy of the patient may impact the decision-making process and warrants further exploration. Furthermore, studies are needed that assess the risks of VAD implantation in patients with ambulatory with different comorbidities and psychosocial profiles to better inform these conversations. The IDECIDE VAD program is a non-commercial, free aid for enhancing shared decision-making.(30)

Third, race and sex bias can influence subjective assessments that are included in the evaluation for allocation of advanced therapies.(7) The assessment tools may also be biased based on the restricted populations within which they were developed and validated or the algorithms utilized.(31) Development and/or implementation of standardized and objective tools to assess psychosocial factors and their association with outcomes is needed.(32) For instance, studies utilizing the Stanford Integrated Psychosocial Assessment for Transplantation (SIPAT) have reported mixed results regarding the association of SIPAT with outcomes post-VAD implantation but provide the most substantial source of objective data and is infrequently used as designed.(33–35) Thus, further work is needed to establish relevant psychosocial factors for VAD outcomes, objective measurement tools that are validated in diverse populations, and implementation of systematic, objective evaluation. Additionally, dedicated training in implicit bias and cultural humility for individuals involved in the allocation process can increase awareness of one’s own unconscious biases and promote ongoing assessment of how individual and group practices can advance equity.(36,37) A national trial (Seeking Objectivity in Allocation of Advanced HF Therapies, SOCIAL HF), led by Dr. Khadijah Breathett, aims to understand whether bias reduction and anti-racism training combined with more objective assessments and enhanced group dynamics reduce the racial, ethnic, and sex-based advanced heart therapy allocation gap.(38) Preliminary work has demonstrated signals of culture and organizational change to promote equity.(39)

Study Limitations

Several limitations of this study should be noted. First, although detailed clinical data is collected and input into the INTERMACS database, certain individual level factors that are not readily captured (e.g., patient preferences, insurance status, or committee disapproval) may have impacted referral, eligibility, and implantation rates. Second, there is no accurate estimate of the number of patients with advanced HF within the US. Thus, census-adjusted rates were utilized to approximate population changes over time with respect to race, ethnicity, sex, and age. This is consistent with prior methods used for this purpose.(5) Third, although INTERMACS is a nationally representative database, low representation of other racial and ethnic groups and low numbers of Hispanic patients precluded more granular analysis of race and sex-based differences. Last, the INTERMACS database represents a large proportion of VAD implants; however, since participation in the registry was not required after 2014, all VADs implanted between 2012 and 2017 may not have been captured. Even so, the number of missing patients is likely to be trivial given the growing number of centers participating in the INTERMACS database during the study period.

Conclusion

From 2012 to 2017, VAD implantation rates in patients with ambulatory HF do not reflect the higher prevalence of HF in Black and Hispanic populations, indicating an allocation disparity. Implantation rates remain lower for women than men, which is likely multifactorial. Overall, 12-month survival post-implantation was high and estimated survival was highest in Black patients with ambulatory HF. Further investigation is needed to understand the reasons for lower relative VAD implantation rates in Black and Hispanic populations as well as differences in implantation rates by sex.

Supplementary Material

supplement

Tweet:

U.S. VAD rates for ambulatory #HF similar for Black & White patients despite higher #HF rates in Black patients and higher survival with VAD than White patients. @DebraDixonMD @KBreathettMD

Clinical Perspectives.

Competency in Medical Knowledge:

Disparities in VAD implantation rates exist by race, ethnicity, and sex in patients with ambulatory HF. Overall survival following VAD implantation is high and VAD implantation in patients with ambulatory HF may improve outcomes for patients with advanced HF.

Translational Outlook:

Future research should examine the individual, institutional, and structural factors influencing VAD implantation rates.

Funding Sources:

Dr. Dixon was supported by the Training in Cardiovascular Research T32 HL007411, Nashville, TN and ACC/ABC Bristol Myers Squibb Research Fellowship, Washington, DC. Dr. Lewsey is supported by the NIA (3R01AG063661-03S1). This study was funded by Dr. Breathett’s support from the National Heart, Lung, and Blood Institute R01HL159216, R56HL159216, K01HL142848, L30HL148881 and HRSA PRIME.

LIST OF ABBREVIATIONS

HF

Heart failure

INTERMACS

Interagency Registry of Mechanically Assisted Circulatory Support

VAD

Ventricular assist device

BMI

body mass index

HR

hazard ratio

Footnotes

Disclosures: There are no disclosures. There are no relationships with industry.

REFERENCES

  • 1.Rose EA, Gelijns AC, Moskowitz AJ et al. Long-Term Use of a Left Ventricular Assist Device for End-Stage Heart Failure. N Engl J Med 2001;345:1435–1443. [DOI] [PubMed] [Google Scholar]
  • 2.Molina EJ, Shah P, Kiernan MS et al. The Society of Thoracic Surgeons Intermacs 2020 Annual Report. Ann Thorac Surg 2021;111:778–792. [DOI] [PubMed] [Google Scholar]
  • 3.Estep JD, Starling RC, Horstmanshof DA et al. Risk Assessment and Comparative Effectiveness of Left Ventricular Assist Device and Medical Management in Ambulatory Heart Failure Patients: Results From the ROADMAP Study. J Am Coll Cardiol 2015;66:1747–1761. [DOI] [PubMed] [Google Scholar]
  • 4.Ambardekar AV, Kittleson MM, Palardy M et al. Outcomes with ambulatory advanced heart failure from the Medical Arm of Mechanically Assisted Circulatory Support (MedaMACS) Registry. J Heart Lung Transplant 2019;38:408–417. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 5.Breathett K, Allen LA, Helmkamp L et al. Temporal Trends in Contemporary Use of Ventricular Assist Devices by Race and Ethnicity. Circ Heart Fail 2018;11:e005008. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Breathett K, Yee E, Pool N et al. Does Race Influence Decision Making for Advanced Heart Failure Therapies? J Am Heart Assoc 2019;8:e013592. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 7.Breathett K, Yee E, Pool N et al. Association of Gender and Race With Allocation of Advanced Heart Failure Therapies. JAMA Netw Open 2020;3:e2011044. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 8.Boyle AJ, Ascheim DD, Russo MJ et al. Clinical outcomes for continuous-flow left ventricular assist device patients stratified by pre-operative INTERMACS classification. The Journal of Heart and Lung Transplantation 2011;30:402–407. [DOI] [PubMed] [Google Scholar]
  • 9.Jorde UP, Kushwaha SS, Tatooles AJ et al. Results of the Destination Therapy Post-Food and Drug Administration Approval Study With a Continuous Flow Left Ventricular Assist Device: A Prospective Study Using the INTERMACS Registry (Interagency Registry for Mechanically Assisted Circulatory Support). J Am Coll Cardiol 2014;63:1751–1757. [DOI] [PubMed] [Google Scholar]
  • 10.Kirklin JK, Naftel DC, Stevenson LW et al. INTERMACS Database for Durable Devices for Circulatory Support: First Annual Report. The Journal of Heart and Lung Transplantation 2008;27:1065–1072. [DOI] [PubMed] [Google Scholar]
  • 11.UAB School of Medicine. Interagency Registry for Mechanically Assisted Circulatory Support - Appendices. Accessed September 26, 2022. https://www.uab.edu/medicine/intermacs/intermacs-documents.
  • 12.Bahrami H, Kronmal R, Bluemke DA et al. Differences in the incidence of congestive heart failure by ethnicity: the multi-ethnic study of atherosclerosis. Arch Intern Med 2008;168:2138–45. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 13.Tsao CW, Aday AW, Almarzooq ZI et al. Heart Disease and Stroke Statistics-2022 Update: A Report From the American Heart Association. Circulation 2022;145:e153–e639. [DOI] [PubMed] [Google Scholar]
  • 14.Ziaeian B, Kominski GF, Ong MK, Mays VM, Brook RH, Fonarow GC. National Differences in Trends for Heart Failure Hospitalizations by Sex and Race/Ethnicity. Circ Cardiovasc Qual Outcomes 2017;10. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 15.Rethy L, Petito LC, Vu THT et al. Trends in the Prevalence of Self-reported Heart Failure by Race/Ethnicity and Age From 2001 to 2016. JAMA Cardiol 2020;5:1425–1429. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 16.Bibbins-Domingo K, Pletcher MJ, Lin F et al. Racial differences in incident heart failure among young adults. N Engl J Med 2009;360:1179–90. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 17.Glynn P, Lloyd-Jones DM, Feinstein MJ, Carnethon M, Khan SS. Disparities in Cardiovascular Mortality Related to Heart Failure in the United States. J Am Coll Cardiol 2019;73:2354–2355. [DOI] [PubMed] [Google Scholar]
  • 18.Breathett K, Knapp SM, Carnes M, Calhoun E, Sweitzer NK. Imbalance in Heart Transplant to Heart Failure Mortality Ratio Among African American, Hispanic, and White Patients. Circulation 2021;143:2412–2414. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 19.Hsich EM. Sex Differences in Advanced Heart Failure Therapies. Circulation 2019;139:1080–1093. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 20.Breathett K, Knapp SM, Carnes M, Calhoun E, Sweitzer NK. Imbalance in Heart Transplant to Heart Failure Mortality Ratio by Sex. Journal of the American Heart Association 2021;10:e020146. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 21.Benjamin EJ, Virani SS, Callaway CW et al. Heart Disease and Stroke Statistics-2018 Update: A Report From the American Heart Association. Circulation 2018;137:e67–e492. [DOI] [PubMed] [Google Scholar]
  • 22.Chang PP, Wruck LM, Shahar E et al. Trends in Hospitalizations and Survival of Acute Decompensated Heart Failure in Four US Communities (2005–2014). Circulation 2018;138:12–24. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 23.Lampropulos JF, Kim N, Wang Y et al. Trends in left ventricular assist device use and outcomes among Medicare beneficiaries, 2004–2011. Open Heart 2014;1:e000109. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 24.Cascino TM, Somanchi S, Colvin M et al. Racial and Sex Inequities in the Use of and Outcomes After Left Ventricular Assist Device Implantation Among Medicare Beneficiaries. JAMA Netw Open 2022;5:e2223080. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 25.Cascino TM, Colvin MM, Lanfear DE et al. Racial Inequities in Access to Ventricular Assist Device and Transplant Persist After Consideration for Preferences for Care: A Report From the REVIVAL Study. Circ Heart Fail 2023;16:e009745. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 26.Breathett K, Liu WG, Allen LA et al. African Americans Are Less Likely to Receive Care by a Cardiologist During an Intensive Care Unit Admission for Heart Failure. JACC Heart Fail 2018;6:413–420. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 27.Breathett K, Yee R, Pool N et al. Group Dynamics and Allocation of Advanced Heart Failure Therapies—Heart Transplants and Ventricular Assist Devices—By Gender, Racial, and Ethnic Group. Journal of the American Heart Association 2023;12:e027701. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 28.Morris AA, Khazanie P, Drazner MH et al. Guidance for Timely and Appropriate Referral of Patients With Advanced Heart Failure: A Scientific Statement From the American Heart Association. Circulation 2021;144:e238–e250. [DOI] [PubMed] [Google Scholar]
  • 29.McIlvennan CK, Magid KH, Ambardekar AV, Thompson JS, Matlock DD, Allen LA. Clinical outcomes after continuous-flow left ventricular assist device: a systematic review. Circ Heart Fail 2014;7:1003–13. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 30.Allen LA, McIlvennan CK, Thompson JS et al. Effectiveness of an Intervention Supporting Shared Decision Making for Destination Therapy Left Ventricular Assist Device: The DECIDE-LVAD Randomized Clinical Trial. JAMA Intern Med 2018;178:520–529. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 31.Givens RC. Are the current evaluation tools for advanced therapies biased? Curr Opin Cardiol 2021;36. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 32.Bui QM, Allen LA, LeMond L, Brambatti M, Adler E. Psychosocial Evaluation of Candidates for Heart Transplant and Ventricular Assist Devices: Beyond the Current Consensus. Circ Heart Fail 2019;12:e006058. [DOI] [PubMed] [Google Scholar]
  • 33.Sperry BW, Ikram A, Alvarez PA et al. Standardized Psychosocial Assessment Before Left Ventricular Assist Device Implantation. Circ Heart Fail 2019;12:e005377. [DOI] [PubMed] [Google Scholar]
  • 34.Bui QM, Braun OO, Brambatti M et al. The value of Stanford integrated psychosocial assessment for transplantation (SIPAT) in prediction of clinical outcomes following left ventricular assist device (LVAD) implantation. Heart Lung 2019;48:85–89. [DOI] [PubMed] [Google Scholar]
  • 35.Cagliostro M, Bromley A, Ting P et al. Standardized Use of the Stanford Integrated Psychosocial Assessment for Transplantation in LVAD Patients. J Card Fail 2019;25:735–743. [DOI] [PubMed] [Google Scholar]
  • 36.Devine PG, Forscher PS, Cox WTL, Kaatz A, Sheridan J, Carnes M. A Gender Bias Habit-Breaking Intervention Led to Increased Hiring of Female Faculty in STEMM Departments. J Exp Soc Psychol 2017;73:211–215. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 37.Qt Capers, Clinchot D, McDougle L, Greenwald AG. Implicit Racial Bias in Medical School Admissions. Acad Med 2017;92:365–369. [DOI] [PubMed] [Google Scholar]
  • 38.ClinicalTrials.gov. NCT05390411: Seeking Objectivity in Allocation of Advanced Heart Failure (SOCIAL HF) Therapies Trial. 2022. Accessed November 13, 2022. https://clinicaltrials.gov/ct2/show/NCT05390411.
  • 39.Breathett K, Yee RH, Pool N et al. Pilot test of a multicomponent implementation strategy for equity in advanced heart failure allocation. Am J Transplant 2023:S1600–6135(23)00348–9. [DOI] [PMC free article] [PubMed] [Google Scholar]

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