Human monocyte-derived macrophages: Pathogenetic role in plaque rupture associated to systemic inflammation

[Features of the course of non-ST elevation myocardial infarction in patients with a history of COVID-19]

Aim      To study the clinical course of non-ST segment elevation myocardial infarction (NSTEMI) in hospitalized patients after COVID-19 and to evaluate the effect of baseline characteristics of patients on the risk of complications.Material and methods  The study included 209 patients with NSTEMI; 104 of them had had COVID-19. The course of myocardial infarction (MI) was analyzed at the hospital stage, including evaluation of the incidence rate of complications (fatal outcome, recurrent MI, life-threatening arrhythmias and conduction disorders, pulmonary edema, cardiogenic shock, ischemic stroke, gastrointestinal bleeding).Results Mean age of patients after COVID-19 was 61.8±12.2 years vs. 69.0±13.0 in the comparison group (p<0.0001). The groups were comparable by risk factors, clinical data, and severity of coronary damage. Among those who have had СOVID-19, there were fewer patients of the GRACE high risk group (55.8 % vs. 74.3 %; p<0.05). Convalescent COVID-19 patients had higher levels of C-reactive protein and troponin I (p<0.05). The groups did not significantly differ in the incidence of unfavorable NSTEMI course (p>0.05). However, effects of individual factors (postinfarction cardiosclerosis, atrial fibrillation, decreased SpO2, red blood cell concentration, increased plasma glucose) on the risk of complications were significantly greater for patients after COVID-19 than for the control group (p<0.05).Conclusion      Patients with NSTEMI, despite differences in clinical history and laboratory data, are characterized by a similar risk of death at the hospital stage, regardless of the past COVID-19. Despite the absence of statistically significant differences in the incidence of in-hospital complications, in general, post-COVID-19 patients showed a higher risk of complicated course of NSTEMI compared to patients who had not have COVID-19. In addition, for this category of patients, new factors were identified that previously did not exert a clinically significant effect on the incidence of complications: female gender, concentration of IgG to SARS-CoV-2 ≥200.0 U/l, concentration of С-reactive protein ≥40.0 mg/l, total protein <65 g/l. These results can be used for additional stratification of risk for cardiovascular complications in patients with MI and also for development of individual protocols for evaluation and management of NSTEMI patients with a history of COVID-19.

Neutrophil Counts, Neutrophil-to-Lymphocyte Ratio, and Systemic Inflammatory Response Index (SIRI) Predict Mortality after Off-Pump Coronary Artery Bypass Surgery

Background: Several perioperative inflammatory markers are postulated to be significant factors for long-term survival after off-pump coronary artery bypass surgery (OPCAB). Hematological parameters, whether single or combined as indices, provide higher predictive values. Methods: The study group comprised 538 consecutive patients (125 (23%) females and 413 (77%) males) with a mean age of 65 ± 9 years, who underwent OPCAB with a mean follow-up time of 4.7 ± 1.7 years. This single-center retrospective analysis included perioperative inflammatory markers such as the neutrophil-to-lymphocyte ratio (NLR), systemic inflammatory response index (SIRI), aggregate index of systemic inflammation (AISI), and systemic inflammatory index (SII). Results: Multivariable analysis identified levels of neutrophils above 4.3 × 109/L (HR 13.44, 95% CI 1.05−3.68, p = 0.037), values of SIRI above 5.4 (HR 0.29, 95% CI 0.09−0.92, p = 0.036) and values of NLR above 3.5 (HR 2.21, 95% CI 1.48−3.32, p < 0.001) as being significant predictors of long-term mortality. The multifactorial models revealed the possibility of strong prediction by combining preoperative factors (COPD, stroke, PAD, and preoperative PLR) and postoperative neutrophil counts (p = 0.0136) or NLR (p = 0.0136) or SIRI (p = 0.0136). Conclusions: Among the postoperative inflammatory indices, the levels of neutrophils, NLR, and SIRI are the most prominent markers for long-term survival after off-pump coronary artery bypass surgery, when combined with preoperative characteristics.

A Novel Monocyte Subset as a Unique Signature of Atherosclerotic Plaque Rupture

The evaluation of monocyte subset distribution among acute coronary syndrome (ACS) patients according to culprit coronary plaque morphology has never been explored. We evaluated whether there were significant differences in frequency of circulating monocyte subsets isolated from ACS patients according to optical coherence tomography (OCT) investigation of plaque erosion and rupture. We enrolled 74 patients with non-ST-elevation ACS (NSTE-ACS), 21 of them underwent OCT investigation of the culprit coronary plaque and local macrophage infiltration (MØI) assessment. As control, we enrolled 30 chronic coronary syndrome (CCS) patients. We assessed the frequency of monocyte subsets in the whole study population, in reliance on their CD14 and CD16 expression (classical, CM: CD14⁺⁺CD16^–; intermediates, IM: CD14⁺⁺CD16⁺; non-classical, NCM: CD14⁺CD16⁺⁺). Then, we tested the effect of lipopolysaccharide (LPS) (a CD14 ligand) on peripheral blood mononuclear cells (PBMCs) of NSTE-ACS patients, quantifying the inflammatory cytokine levels in cell-culture supernatants. Our data proved that monocyte subsets isolated from NSTE-ACS patients represent a peculiar biological signature of the pathophysiological mechanism lying beneath atherosclerotic plaque with a ruptured fibrous cap (RFC) as compared with plaque erosion. Moreover, the magnitude of LPS-mediated effects on IL-1β, IL-6, and IL-10 cytokine release in cell-culture supernatants appeared to be greater in NSTE-ACS patients with RFC. Finally, we described a fourth monocyte population never explored before in this clinical setting (pre-classical monocytes, PCM: CD14⁺CD16^–) that was prevalent in NSTE-ACS patients as compared with CCS and, especially, in patients with RFC and culprit plaque with MØI.