Anemia Linked to Adverse Outcomes After Percutaneous Coronary Intervention

William W. O’Neil, MD

Credit: Henry Ford Health Care System

Baseline anemia is frequently identified in patients undergoing Impella-supported high-risk percutaneous coronary intervention (HRPCI), according to the results of a recent post hoc analysis of the PROTECT III study.¹

The presence of anemia in this population undergoing PCI was correlated with major adverse cardiovascular and cerebrovascular events (MACCE), bleeding events, and death, suggesting the need to consider the hematologic condition during risk stratification.

“Current clinical guidelines lack recommendations for the concurrent management of anemia in patients undergoing PCI or large-bore procedures such as Impella-supported HRPCI, other than advising measures to minimize bleeding risks and utilizing risk scores to guide dual antiplatelet therapy,” wrote the investigative team, led by William W. O’Neil, MD, center for structural heart disease, department of cardiology, Henry Ford Health Care System.

Nearly one-quarter of the global population is affected by anemia, particularly among individuals aged ≥65 years.² Underlying anemia has been linked with worse outcomes in patients with coronary artery disease, those undergoing transcatheter aortic valve replacement, and those undergoing PCI, including in-hospital and long-term adverse events.

Impella is a percutaneous left ventricular assistant device (pLVAD) increasingly utilized for mechanical circulatory support during PCI to provide hemodynamic support and allow for complete revascularization.³ Notably, large-bore access procedures, including Impella-supported HRPCI can increase the risk of bleeding.

Given the lack of clear guidelines on the management of anemia in patients undergoing PCI, O’Neil and colleagues investigated patient characteristics to evaluate the link between anemia and adverse outcomes in the cVAD PROTECT III study.¹

PROTECT III enrolled 1237 patients who underwent Impella-supported HRPCI across 46 centers in North America between March 2017 and March 2020. This analysis focused on patients with baseline hemoglobin levels available, according to World Health Organization criteria.

Patients were separated into three cohorts based on WHO hemoglobin criteria, including no anemia (≥12 mg/dL for women and ≥13 mg/dL for men), mild anemia (≥10 to <12 mg/dL in women and ≥10 to <13 mg/dL in men), and moderate or severe anemia (<10 mg/dL in men and women).

The analysis’ primary endpoint was MACCE at 30 and 90 days, with major bleeding events, duration of hospitalization, major vascular or structural complications requiring surgery, and 1-year all-cause mortality comprising the secondary endpoints.

Among the total study population, 1071 had baseline hemoglobin data available. At baseline, 37.9% had no anemia, 43.4% had mild anemia, and 18.7% had moderate or severe anemia. Those with anemia were characterized by older age and exhibited a greater burden of comorbidities, including chronic kidney disease and diabetes.

Upon analysis, moderate to severe anemia was linked to significantly higher MACCE rates than patients with mild anemia or no anemia at 30 days (12.3% vs. 9.8% vs. 5.4%, respectively; overall log-rank P-value = .02). These differences continued at 90 days in those with moderate to severe anemia (18.7% vs. 14.6% vs. 8.3%; P = .004).

Multivariable analysis was performed to adjust for age, sex, left ventricular ejection fraction, and eGFR. Overall, these data showed both mild and moderate to severe anemia were correlated with higher MACCE rates at 30 days and 90 days. Sensitivity analysis, excluding patients with dialysis, reported similar results.

In addition, a higher number of patients with moderate to severe anemia and mild anemia experienced major bleeding incidnts, compared with those without anemia (5.5% vs. 1.2%; P = .002). After relevant adjustment, multivariable logistic regression models found moderate to severe anemia was independently associated with major bleeding (adjusted odds ratio [aOR], 2.53; 95% CI, 1.37–4.68; P = .003).

“The extent to which these associations between anemia and adverse events after complex PCI can be mitigated by optimized anemia management and tailored interventions remains to be established,” O’Neil and colleagues wrote.

Reference

1. _{Falah B, Redfors B, Zhao D, et al. Implications of anemia in patients undergoing PCI with Impella-support: insights from the PROTECT III study. Front Cardiovasc Med. 2024;11:1429900. Published 2024 Jul 18. doi:10.3389/fcvm.2024.1429900}
2. _{GBD 2021 Anaemia Collaborators. Prevalence, years lived with disability, and trends in anaemia burden by severity and cause, 1990-2021: findings from the Global Burden of Disease Study 2021 [published correction appears in Lancet Haematol. 2023 Oct;10(10):e796. doi: 10.1016/S2352-3026(23)00283-1] [published correction appears in Lancet Haematol. 2024 Jan;11(1):e10. doi: 10.1016/S2352-3026(23)00373-3]. Lancet Haematol. 2023;10(9):e713-e734. doi:10.1016/S2352-3026(23)00160-6}
3. _{Amin AP, Spertus JA, Curtis JP, et al. The Evolving Landscape of Impella Use in the United States Among Patients Undergoing Percutaneous Coronary Intervention With Mechanical Circulatory Support. Circulation. 2020;141(4):273-284. doi:10.1161/CIRCULATIONAHA.119.044007}