Prognosis of Patients with Chronic and Hospital-Acquired Anaemia After Acute Coronary Syndromes

Postoperative anemia in cardiac surgery patients: a narrative review

PURPOSE

Anemia reduces the blood's ability to carry and deliver oxygen. Following cardiac surgery, anemia is very common and affects up to 90% of patients. Nevertheless, there is a paucity of data examining the prognostic value of postoperative anemia. In this narrative review, we present findings from the relevant literature on postoperative anemia in cardiac surgery patients, focusing on the incidence, risk factors, and prognostic value of postoperative anemia. We also explore the potential utility of postoperative anemia as a therapeutic target to improve clinical outcomes.

SOURCE

We conducted a targeted search of MEDLINE, Embase, and the Cochrane Database of Systematic Reviews up to September 2022, using a combination of search terms including postoperative (post-operative), perioperative (peri-operative), anemia (anaemia), and cardiac surgery.

PRINCIPAL FINDINGS

The reported incidence of postoperative anemia varied from 29% to 94% across the studies, likely because of variations in patient inclusion criteria and classification of postoperative anemia. Nonetheless, the weight of the evidence suggests that postoperative anemia is common and is an independent risk factor for adverse postoperative outcomes such as acute kidney injury, stroke, mortality, and functional outcomes.

CONCLUSIONS

In cardiac surgery patients, postoperative anemia is a common and prognostically important risk factor for postoperative morbidity and mortality. Nevertheless, there is a lack of data on whether active management of postoperative anemia is feasible or effective in improving patient outcomes.

Prognostic implication of hemoglobin reduction with and without clinical bleeding after percutaneous coronary intervention in patients with acute coronary syndromes

BACKGROUND

Bleeding events are associated with higher mortality rates in patients with cardiovascular diseases, including patients presenting with acute coronary syndrome (ACS) undergoing coronary revascularization. We aimed to determine whether a reduction in hemoglobin (Hgb) from pre- to postpercutaneous coronary intervention (PCI), with or without evidence of clinical bleeding, is a correlate of in-hospital mortality for patients presenting with ACS who underwent primary PCI.

METHODS

We divided 33816 consecutive patients with ACS who underwent PCI into three categories: (1) target group (defined as Hgb reduction without overt bleeding [n = 112]); (2) Hgb reduction with overt bleeding (n = 48); and (3) control group (defined as no Hgb reduction and no overt bleeding [n = 3156]). Hgb reduction was defined as a drop of >3 g/dL in Hgb value from preprocedure and postprocedure during the index hospitalization. The primary outcome was in-hospital mortality. We used logistic regression to examine the relationship between Hgb reduction with and without bleeding and in-hospital mortality.

RESULTS

In crude analysis, the Hgb reduction with overt bleed group had a higher in-hospital mortality rate (16.7%) than the target (9.8%) and control groups (0.6%). Adjusted logistic regression estimates a 0.393 (95% confidence interval [CI]: 0.137, 1.869) odds ratio for in-hospital death of the target group over the Hgb reduction with bleed group, and a 54.517 (95% CI: 2.07, >1000) odds ratio of the target group over the control group.

CONCLUSIONS

In patients presenting with ACS undergoing PCI, Hgb reduction with and without overt bleeding were both independently associated with in-hospital mortality.

Pharmacological treatment of cardiogenic shock - A state of the art review

Cardiogenic shock is a clinical syndrome of impaired tissue perfusion caused by primary cardiac dysfunction and inadequate cardiac output. It represents one of the most lethal clinical conditions in intensive care medicine with mortality >40%. Management of different clinical presentations of cardiogenic shock includes guidance of cardiac preload, afterload, heart rate and contractility by differential pharmacological modulation of volume, systemic and pulmonary vascular resistance and cardiac output besides reversing the triggering cause. Data from large registries and randomized controlled trials on optimal diagnostic guidance as well as choice of pharmacological agents has accrued significantly in recent years. This state-of-the-art review summarizes the basic concepts of cardiogenic shock, the diagnostic work-up and currently available evidence and guideline recommendations on pharmacological treatment of cardiogenic shock.

The role of anemia on admission in acute coronary syndrome - An umbrella review of systematic reviews and meta-analyses

INTRODUCTION

The role of erythrocytes in the acute coronary syndrome (ACS) is complex. The aim of this review in terms of PICO (P: patients; I: intervention; C: comparison; O: outcome) was to summarize systematic reviews in patients (P) with acute coronary syndrome, evaluating the effects of (I) 1) iron deficiency, 2) administration of an erythropoiesis-stimulating agent (ESA), 3) anemia on admission, 4) red blood cell transfusion, 5) a restrictive transfusion strategy in comparison (C) to 1) no iron deficiency, 2) no ESA 3) no anemia on admission, 4) no red blood cell transfusion, 5) a liberal transfusion strategy on mortality (O).

METHODS

We used AMSTAR2 to assess the methodological quality of systematic reviews and grade the available research. The primary endpoint was all-cause mortality.

RESULTS

Using the data from 2,787,005 patients, the following conditions were associated with worse outcome in patients with ACS: anemia on admission (RR 2.08 95%CI 1.70-2.55) and transfusion (1.93 95%CI 1.12-3.34) of red blood cells. A liberal transfusion (RR 0.86 95%CI 0.70-1-05), administration of ESA (RR 0.55 95%CI 0.22-1.33) and iron deficiency (OR 1.24 95%CI 0.12-13.13) were not associated with altered all-cause mortality.

CONCLUSION

Patients suffering from ACS and anemia on admission are at particular risk for adverse outcome. There is evidence of associations between adverse outcomes and receiving red blood cell transfusions.

Association of In-Hospital Hemoglobin Drop With Decreased Myocardial Salvage and Increased Long-Term Mortality in Patients With Acute ST-Segment-Elevation Myocardial Infarction

Background

Anemia and blood loss occur often in patients with ST‐segment–elevation myocardial infarction (STEMI). In‐hospital hemoglobin drop is associated with 1‐year mortality in patients with acute coronary syndrome. However, data on the effect of hemoglobin reduction on myocardial salvage and long‐term outcomes are scarce. We investigated the impact of in‐hospital hemoglobin drop on myocardial salvage and 5‐year mortality in patients with STEMI treated with primary percutaneous coronary intervention.

Methods and Results

In‐hospital hemoglobin drop was defined as a decrease in hemoglobin levels from admission and nadir hemoglobin values. Patients were categorized as having the following: no drop, minimal drop (<3 g/dL), minor drop (≥3 to <5 g/dL), and major drop (≥5 g/dL). Myocardial area at risk and infarct size were measured using serial single‐photon emission computerized tomography imaging. The co‐primary outcomes were myocardial salvage and 5‐year all‐cause mortality. Of 1204 patients, 1169 (97.1%) showed a hemoglobin drop during hospitalization: minimal, minor, and major drop occurred in 894 (74.3%), 214 (17.8%), and 61 (5.1%) patients, respectively. Myocardial salvage was reduced in patients with minimal (median, 0.53 [interquartile range, 0.27–0.83]), minor (median, 0.40 [interquartile range, 0.18–0.62]), and major (median, 0.40 [interquartile range, 0.14–0.77]) drop compared with patients without drop (median, 0.70 [interquartile range, 0.44–1.0], P<0.001). After adjusting for covariates, hemoglobin drop remained an independent correlate of poor myocardial salvage. A drop of ≥3 g/dL was associated with reduced left ventricular function at 6 months and with increased mortality at 5‐year follow‐up after STEMI.

Conclusions

In patients with STEMI undergoing primary percutaneous coronary intervention, in‐hospital hemoglobin drop was associated with reduced myocardial salvage, left ventricular function, and increased long‐term mortality.

Acute Anemia and Myocardial Infarction

Various studies have established the prognosis of anemia in myocardial infarction (MI). Both chronic and acute anemia lead to poor outcomes in MI. Regardless, the association of anemia with MI and its management varies. In this study, the literature was analyzed to determine the association between acute anemia and MI based on the pathophysiology, outcomes, and management options. Acute anemia results in decreased blood supply and sudden hypoxia to the heart. Additionally, it exacerbates the preexisting compromised coronary blood supply in patients with MI. Thus, there is a disproportionate oxygen supply and demand ratio to the heart. It was found that anemia increases all-cause mortality in acute MI. However, it is unclear whether anemia is the direct contributor to mortality in these patients. For the management of MI, percutaneous coronary intervention (PCI) is commonly used. Increased incidence of hospital-acquired anemia (HAA) is reported in patients after PCI. However, the cause of HAA in these patients is not well established. Antiplatelet therapy in these patients is also considered to be the culprit for HAA. Nonetheless, no clear evidence is available. There is no consensus or criteria for the treatment of acute anemia in MI patients. Researchers have explored management options such as blood transfusion, erythropoietin-stimulating agent, and iron therapy. Further studies are warranted for a better understanding and management of MI in patients with anemia and vice versa.

Prognostic Implications of Declining Hemoglobin Content in Patients Hospitalized With Acute Coronary Syndromes

BACKGROUND

Contemporary definitions of bleeding endpoints are restricted mostly to clinically overt events. Whether hemoglobin drop per se, with or without overt bleeding, adversely affects the prognosis of patients with acute coronary syndrome (ACS) remains unclear.

OBJECTIVES

The aim of this study was to examine in the MATRIX (Minimizing Adverse Haemorrhagic Events by Transradial Access Site and Systemic Implementation of Angiox) trial the incidence, predictors, and prognostic implications of in-hospital hemoglobin drop in patients with ACS managed invasively stratified by the presence of in-hospital bleeding.

METHODS

Patients were categorized by the presence and amount of in-hospital hemoglobin drop on the basis of baseline and nadir hemoglobin values and further stratified by the occurrence of adjudicated in-hospital bleeding. Hemoglobin drop was defined as minimal (<3 g/dl), minor (≥3 and <5 g/dl), or major (≥5 g/dl). Using multivariate Cox regression, we modeled the association between hemoglobin drop and mortality in patients with and without overt bleeding.

RESULTS

Among 7,781 patients alive 24 h after randomization with available hemoglobin data, 6,504 patients (83.6%) had hemoglobin drop, of whom 5,756 (88.5%) did not have overt bleeding and 748 (11.5%) had overt bleeding. Among patients without overt bleeding, minor (hazard ratio [HR]: 2.37; 95% confidence interval [CI]: 1.32 to 4.24; p = 0.004) and major (HR: 2.58; 95% CI: 0.98 to 6.78; p = 0.054) hemoglobin drop were independently associated with higher 1-year mortality. Among patients with overt bleeding, the association of minor and major hemoglobin drop with 1-year mortality was directionally similar but had wider CIs (minor: HR: 3.53 [95% CI: 1.06 to 11.79]; major: HR: 13.32 [95% CI: 3.01 to 58.98]).

CONCLUSIONS

Among patients with ACS managed invasively, in-hospital hemoglobin drop ≥3 g/dl, even in the absence of overt bleeding, is common and is independently associated with increased risk for 1-year mortality. (Minimizing Adverse Haemorrhagic Events by Transradial Access Site and Systemic Implementation of Angiox; NCT01433627).