Sex Disparities in Mechanical Circulatory Support: Implications for Critical Care Anesthesiologists

by Amanda Arnzen, MD
WICC Member, SOCCA
University of Nebraska Medical Center, Omaha, Nebraska

Nazish K Hashmi, MD, MBBS
WICC Member, SOCCA
Vice Chair, SOCCA Program Directors Advisory Council
Duke University Hospital, Durham, NC

Amanda Kore Schilling, DO
WICC Member, SOCCA Membership Committee
University of Arizona, Banner University Medical Center, Tucson, AZ

Volume 36 | Issue 4 | Dec 2025

Life it is not just a series of calculations and a sum total of statistics, it’s about experience, it’s about participation, it is something more complex and more interesting than what is obvious.

-Daniel Libeskind

Women are less likely to receive mechanical circulatory support, regardless of modality: extracorporeal cardiopulmonary resuscitation (ECPR), extracorporeal membrane oxygenation (ECMO), Impella, and intra-aortic balloon pump (IABP).1

It is a long-standing anecdote within the scientific community that statistics can be manipulated to fit an agenda. It is nonetheless concerning that healthcare disparities regarding advanced cardiac life support are consistent and reproducible, with statistically significant P- values demonstrating disparities in the numbers of women, compared to men, placed on mechanical circulatory support (MCS). Conversations among critical care physicians regarding the “why?” and “how can this be modified in the future?” need to begin. From the mid-2000’s onward, a growing trend of articles describing sex disparities among patients receiving MCS have been published. While the etiology of cardiogenic shock refractory to medical therapy varies among men and women, when controlling for confounders, a multitude of databases conclude that there is a disparity in utilization of mechanical circulatory support according to sex, including the Journals of the Canadian Cardiovascular Society, American College of Cardiology, Annals of American Thoracic Society.1,3-10

In Sex-Based Disparities In Mechanical Circulatory Support Usage Among Postmenopausal Patients with Cardiogenic Shock, a sample group from the National Inpatient Sample database for 2018-2021 demonstrated a statistically significant disparity in the application of mechanical circulatory support; including IABP, Impella, and ventricular assist devices.10,14 Specifically, when compared to men, women tended to be slightly older with lower comorbidity index, and lower MCS usage. Despite adjusting for age, Elixhauser index, race, type of insurance, and income, women still had 27.5% lower odds of receiving MCS and 17% higher odds of inpatient mortality.14 According to one study of patients with cardiogenic shock due to acute myocardial infarction (AMI-CS), women placed on MCS were on average older, more likely to be Black, and had a higher burden of comorbidities as defined by the Charleson comorbidity index. These patients also experienced higher in-hospital mortality, palliative care, and DNR status.10

Why?
The negative medical outcomes associated with gender disparities beg us to evaluate the differences in morbidity and clinical management in the subset of AMI-CS patients. The understanding that these gender disparities are rooted in variations of pathophysiology may be imperative to quickly and safely implementing the changes needed to save lives.

In the AMI-CS population, women initially present at older ages and with different comorbidities than their male counterparts. Diabetes and hypertension contribute to a frequently-silent coronary artery disease (CAD) process in women, whereas men predominantly present with symptomatic CAD, resulting in interventions prior to their cardiogenic shock.7 The delayed presentation of AMI in women results in longer ischemic times and higher baseline acuity as measured by CardShock scores.11 It is unclear whether this leads to the higher incidences of heart failure and subsequent hemodynamic instability, which in turn decrease their rates of percutaneous coronary intervention.10 Women with AMI-CS receive fewer MCS devices, less escalation to ECMO support, and have a higher incidence of respiratory failure leading to mechanical ventilation. Ultimately, women show higher inpatient mortality and a more frequent use of palliative care consultations. These higher mortality rates mirror the gender disparity trends noted in all areas of acute cardiovascular care.10

How can we bring change? Moving forward, how can teams address implicit bias?
Should we extrapolate the risk factors seen in AMI-CS women to our preoperative considerations and intraoperative management? Based on the current literature, we can say that women with a known history of diabetes and hypertension may warrant greater caution when clinicians assess their cardiac risk for adverse intraoperative cardiac events due to their silent and delayed presentations. Understanding that women with non-ST-elevation myocardial infarctions (NSTEMIs) may present in a more critical state and deteriorate faster, allows us to advocate for MCS devices earlier in the perioperative period or temporarily defer cases until a shock team has evaluated the patient’s candidacy for MCS. There remains a need for sex-specific considerations in cardiogenic shock management, including recognition of unique presentations in pregnancy-related conditions, spontaneous coronary artery dissection, and Takotsubo cardiomyopathy.12 Vascular access planning becomes particularly crucial to reduce femoral vessel complications in women with smaller anatomy.13 Lastly, highlighting these gender differences in pathophysiology may allow quicker recognition of a decompensating cardiogenic shock patient in the perioperative period. Information is powerful when it comes to saving lives. Truly understanding the issues of gender disparities in the MCS population can be an asset to our practice as anesthesiologists.

References

  1. Mehta, A.B., et al., Disparities in Adult Patient Selection for Extracorporeal Membrane Oxygenation in the United States: A Population-Level Study. Annals of the American Thoracic Society, 2023. 20(8): p. 1166–1174.
  2. Steverson, M. Aging and Health. 2025; Available from: https://www.who.int/news-room/fact-sheets/detail/ageing-and-health.
  3. Abdallah, N., et al., OR6-4 | Gender Disparities in Temporary Mechanical Circulatory Support in Patients with Acute Myocardial Infarction and Cardiogenic Shock. Journal of the Society for Cardiovascular Angiography & Interventions, 2024. 3(5).
  4. Balucani, C., et al., Sex-Related Differences in Utilization and Outcomes of Extracorporeal Cardio-Pulmonary Resuscitation for Refractory Cardiac Arrest. Asaio j, 2024. 70(9): p. 750–757.
  5. Bhardwaj, A. and J. Contreras, Understanding and Eliminating Disparities for Women Needing Mechanical Circulatory Support. JACC Heart Fail, 2023. 11(12): p. 1705–1707.
  6. Castro, L., et al., Worldwide Gender Differences during Mechanical Circulatory Support: An Analysis of the International Society for Heart and Lung Transplantation Mechanically Assisted Circulatory Support Registry Data. The Journal of Heart and Lung Transplantation, 2021. 40(4, Supplement): p. S102.
  7. Diaz-Arocutipa, C., et al., Gender Disparities on the Use and Outcomes of Mechanical Circulatory Support in Patients With Cardiogenic Shock Complicating Acute Myocardial Infarction. Am J Cardiol, 2024. 233: p. 65–73.
  8. Luna, P., et al., Sex Disparities in the Management, Outcomes, and Transfer of Patients Hospitalized for Cardiogenic Shock. J Soc Cardiovasc Angiogr Interv, 2024. 3(3Part A): p. 101212.
  9. Spaulding, C., Racial, Ethnic, and Sex Disparities in Cardiogenic Shock Due to STEMI: ACT NOW! JACC Cardiovasc Interv, 2021. 14(6): p. 661–663.
  10. Vallabhajosyula, S., et al., Sex Disparities in the Use and Outcomes of Temporary Mechanical Circulatory Support for Acute Myocardial Infarction-Cardiogenic Shock. CJC Open, 2020. 2(6): p. 462–472.
  11. Epps, K.C., et al., Sex-Related Differences in Patient Characteristics, Hemodynamics, and Outcomes of Cardiogenic Shock: INOVA-SHOCK Registry. J Soc Cardiovasc Angiogr Interv, 2023. 2(5).
  12. Davis, M.B., et al., Peripartum Cardiomyopathy: JACC State-of-the-Art Review. J Am Coll Cardiol, 2020. 75(2): p. 207–221.
  13. Cheng, R., et al., Complications of extracorporeal membrane oxygenation for treatment of cardiogenic shock and cardiac arrest: a meta-analysis of 1,866 adult patients. Ann Thorac Surg, 2014. 97(2): p. 610–6.
  14. Gupta S, Syed TW, Timilsina B, Beshai R. Abstract 4362359: Sex-Based Disparities In Mechanical Circulatory Support Usage Among Postmenopausal Patients With Cardiogenic Shock. Circulation. 2025;152(Suppl_3):A4362359-A4362359.