DefinePK

Abstract

The recent study by Shah and colleagues, "Association of Hemoglobin Level with In-Hospital Outcomes in Patients with STEMI Treated with Primary Percutaneous Coronary Intervention," brings renewed attention to the clinical impact of anemia in patients presenting with ST-elevation myocardial infarction (STEMI) [1]. Conducted at the Hayatabad Medical Complex in Pakistan, this retrospective study highlights a compelling association: lower hemoglobin levels at presentation correlate with higher rates of major adverse cardiac events (MACE) and in-hospital mortality. These findings underscore the need to reevaluate the role of hemoglobin as a prognostic marker—and potentially, a modifiable factor—in acute cardiac care.
Despite significant advances in reperfusion strategies and emergency care, STEMI remains a leading cause of morbidity and mortality worldwide [2]. Among the modifiable risk factors that often go unrecognized in this context is anemia, typically defined as a hemoglobin level below 13 g/dL in men and 12 g/dL in women [3]. Anemia is prevalent in patients with acute coronary syndromes and may exacerbate myocardial ischemia by impairing oxygen delivery to already compromised tissue [4].
In Shah et al.'s cohort, mortality ranged from approximately 4% in patients with normal hemoglobin to nearly 20% in those with severe anemia. MACE—including heart failure, arrhythmias, and cardiogenic shock—was also significantly more common among anemic individuals. Notably, the statistical analysis demonstrated that severe anemia was an independent predictor of in-hospital mortality, with the risk of death more than doubling in this group.
These findings have practical implications for clinical decision-making. While early reperfusion remains the cornerstone of STEMI management, the initial evaluation should not overlook hemoglobin levels, which may offer valuable prognostic information. Current transfusion guidelines advocate for a restrictive strategy, generally recommending transfusion only when hemoglobin drops below 7–8 g/dL or when symptoms of anemia emerge. Yet this study suggests that even moderate anemia may carry prognostic weight. This raises important questions about whether clinical thresholds for intervention should be reconsidered, or at least more individualized.
Rather than defaulting to transfusion—which carries its own risks—clinicians might consider broader strategies: optimizing hemodynamics, minimizing procedural blood loss, and addressing reversible causes of anemia such as iron deficiency or chronic disease. Early detection of anemia could enable timely and targeted interventions, potentially improving outcomes without relying solely on transfusion-based strategies.
Nevertheless, the study has important limitations. Its retrospective nature precludes causal inference, and its single-center setting in Pakistan may limit generalizability to other healthcare systems or populations. Larger prospective, multicenter trials are needed to validate these findings and guide evidence-based protocols. Future research should explore optimal hemoglobin thresholds for intervention, the timing and volume of transfusion when warranted, and the utility of adjunctive therapies such as iron supplementation or erythropoietin.
An additional opportunity lies in better understanding how anemia interacts with common STEMI comorbidities like diabetes and chronic kidney disease. These interactions may demand a more personalized approach to risk stratification and management.
Beyond the clinical sphere, this study also carries public health implications. In countries where nutritional deficiencies and chronic diseases are prevalent, population-level anemia screening and prevention strategies could play a pivotal role in reducing the burden of cardiovascular events. Integrating early hemoglobin assessment into STEMI protocols and educating frontline providers on its importance could enhance both patient care and system-level efficiency.
The association between anemia and poor in-hospital outcomes in STEMI patients undergoing PCI, as demonstrated by Shah et al., invites renewed attention to a potentially modifiable risk factor in acute cardiac care. Their findings reinforce the need for routine hemoglobin evaluation at presentation and support the integration of anemia management into comprehensive STEMI care pathways. As the field moves toward increasingly personalized and precise cardiovascular medicine, even modest adjustments—like addressing anemia early—could make a significant difference in patient outcomes.
References

Shah SK, Danish N, Akhtar S, Khalil MSUD, Ali N, Amin QNU. Association of Hemoglobin Level with In-Hospital Outcomes in Patients with STEMI Treated with Primary Percutaneous Coronary Intervention. Pak Heart J. 2025;58(02):252-7. DOI: 10.47144/phj.v58i2.2786
Vernon ST, Coffey S, D'Souza M, Chow CK, Kilian J, Hyun K, et al. ST-Segment-Elevation Myocardial Infarction (STEMI) Patients Without Standard Modifiable Cardiovascular Risk Factors-How Common Are They, and What Are Their Outcomes? J Am Heart Assoc. 2019;8(21):e013296. DOI: 10.1161/JAHA.119.01329.
Prabhakar SK, Abbott JD. Factors influencing the outcomes of percutaneous coronary intervention in the stent era. Interv Cardiol. 2012;4(5):557-68. DOI:10.2217/ica.12.59
Rhodes CE, Denault D, Varacallo MA. Physiology, oxygen transport [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan– [updated 2022 Nov 14; cited 2025 Jun 5]. Available from: https://www.ncbi.nlm.nih.gov/books/NBK538336/