Original Clinical Science
Presence and impact of anemia in patients supported with left ventricular assist devices

https://doi.org/10.1016/j.healun.2023.04.013Get rights and content

Background

Data on anemia and its effects on patients supported with continuous-flow left ventricular assist devices (LVADs) are lacking.

Objectives

This study sought to describe the presence of anemia over time and investigate its association with mortality, quality of life, exercise capacity, and adverse events in LVAD patients.

Methods

Adults receiving durable LVADs between 2008 and 2017 were identified from the INTERMACS database. The full cohort was stratified according to anemia severity (no anemia, mild, and moderate-severe).

Results

The analysis of 19,509 patients (females: 21.2%, age: 56.9 ± 12.9 years) showed that moderate-severe anemia affected 45.2% of patients at baseline, 33.5% of them at 6 months, and 32.3% in the fourth year after implantation. The presence of normal hemoglobin was 24.4% before surgery, 32.5% at 6 months, and 36.6% at 4 years after implantation. Multivariable linear mixed-effect regression revealed that the average hemoglobin over time was significantly lower (β, −0.233, 95% confidence interval (CI): −0.282 to −0.185), and the reduction of hemoglobin over time was bigger (β, −0.032 95% CI: −0.035 to −0.028) for LVAD nonsurvivors compared with LVAD survivors. Adjusted Cox regression showed that the severity of preimplant anemia was associated with higher mortality (HR, mild: 1.19; 95% CI: 1.05-1.35 and moderate-severe: 1.44; 95% CI: 1.28-1.62), with similar results in competing risk regression.

Anemia progression during follow-up was associated with decreased Kansas City Cardiomyopathy Questionnaire scores and shorter 6-minute walk distances.

Conclusions

In patients supported with LVADs, anemia is a frequent comorbidity, and deterioration over time is associated with poor prognosis.

Section snippets

Data source and ethical considerations

Analysis was conducted using the INTERMACS database, a prospective registry of all Food and Drug Administration-approved durable mechanical circulatory support devices in the United States.9 Data for the current study were requested via the Biologic Specimen and Data Repository Information Coordinating Center of the National Heart, Lung, and Blood Institute (https://biolincc.nhlbi.nih.gov/home/). This study was approved by the First Affiliated Hospital of Chongqing Medical University Ethics

Study population and baseline characteristics

A total of 22,008 patients who underwent a VAD implant were included in the INTERMACS registry between 2008 and 2017. Of them, 19,597 received a primary continuous-flow LVAD implant and were included in the current study (Figure 1). The primary analysis comprises 19,509 patients with available preimplant hemoglobin values: 4,758 (24.4%) patients did not show any preimplant anemia, 5,935 (30.4%) had mild anemia, and 8,816 (45.2%) had moderate-severe anemia. Baseline characteristics of patients

Discussion

This study analyzed data from the INTERMACS database to investigate anemia presence and its impact on advanced HF patients receiving LVAD implantations. The present study has 3 main findings (Central Illustration). First, more than 75% of LVAD candidates have preimplant anemia. Although hemoglobin values increased over time, anemia remains a significant problem after LVAD implantation, with 31.2%-34.0% and 32.3%-33.5% of LVAD patients characterized by mild or moderate-severe anemia,

Strengths and limitations

The structured and systematic data collection performed by the INTERMACS database, the regular audits on data quality, and the large participation of cardiac surgery centers guarantee data robustness and granularity. Nevertheless, our study is observational by nature limiting causal inferences, and this includes the trajectories over time. In fact, modeling the trajectories in hemoglobin over time using linear mixed-effect models has the advantage to estimate differences in hemoglobin between

Conclusions

Anemia can affect more than 75% of candidates for LVAD surgery and 60.4%-67.6% of LVAD recipients from 6 months to 4 years after implantation. Any degree of anemia is correlated with higher mortality risk, worse quality of life, and poor functional status after LVAD implantation, and it might drive higher rates of bleeding events, infections, renal dysfunction, and rehospitalizations. Consequently, preimplant anemia is a significant determinant of mortality in LVAD patients. Further studies

Perspectives

Competency in medical knowledge: Anemia is a frequent comorbidity in patients before and after LVAD implant. It is associated with worse quality of life, poor functional status, higher mortality risk, and higher adverse events after LVAD implantation.

Translational Outlook: Further studies should focus on identifying the best therapeutic approach for anemia to improve the quality of life and survival of LVAD patients.

Disclosures

RL is a consultant for Medtronic, Getinge, Abiomed, and LivaNova; Advisory Board Member of Eurosets, Hemocue, and Xenios (honoraria are paid as research funding). The remaining authors have nothing to disclose.

Funding

This work was supported by the National Natural Science Foundation of China (No. 81700602), the First-class Discipline Construction Project of First Clinical College, Chongqing Medical University (No. CYYY-BSHPYXM-2022-08), the Natural Science Foundation of Chongqing, China (No. CSTB2022NSCQ-MSX0840), the CQMU Program for Youth Innovation in Future Medicine (W0153), the First Affiliated Hospital of CQMU Young Outstanding Scientific and Technological Talents Program (ZYRC2022-04), and the Senior

Acknowledgments

This article was performed using the data from INTERMACS obtained from the National Heart, Lung, and Blood Institute (NHLBI) Biologic Specimen and Data Repository Information Coordinating Center.

References (32)

  • I.S. Anand et al.

    Anemia and iron deficiency in heart failure: current concepts and emerging therapies

    Circulation

    (2018)
  • T.A. McDonagh et al.

    ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: developed by the task force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC) With the special contribution of the Heart Failure Association (HFA) of the ESC

    Eur Heart J

    (2021)
  • B.N. Grote et al.

    Anemia in heart failure: still relevant?

    JACC Heart Fail

    (2018)
  • T. Li et al.

    Is there a sex gap in outcomes of comparable patients supported with left ventricular assist devices?

    Artif Organs

    (2022)
  • J. Suarez et al.

    Mechanisms of bleeding and approach to patients with axial-flow left ventricular assist devices

    Circ: Heart Fail

    (2011)
  • S. Mariani et al.

    Sex differences in outcomes following less-invasive left ventricular assist device implantation

    Ann Cardiothorac Surg

    (2021)
  • Cited by (2)

    View full text