Predictive Value of Mean Platelet Volume in Saphenous Vein Graft Disease

The Prognostic Significance of Red Cell Distribution Width in Cardiac Surgery: A Systematic Review and Meta-Analysis

RED CELL DISTRIBUTION WIDTH (RDW) is a routinely available biomarker of likely erythropoietic dysfunction, which may be associated with adverse outcomes after cardiac surgery. This systematic review and meta-analysis aimed to clarify the prognostic value of RDW in patients undergoing cardiac surgery. The authors searched MEDLINE, Embase, and the Cochrane Library from inception to May 10, 2022 for studies investigating the association between elevated RDW (as defined by the authors of included studies) and adverse outcomes after cardiac surgery. Herein, the authors extracted maximally adjusted hazard ratios (HRs) and odds ratios (ORs) with associated CIs, and pooled them using random-effects inverse- variance modeling. The authors explored interstudy heterogeneity using metaregression. The authors included 26 studies involving 48,092 patients who had undergone cardiac surgery. Elevated preoperative RDW was associated with long-term mortality (pooled HR 1.63, 95% CI 1.05-2.52), short-term mortality (pooled OR 2.16, 95% CI 1.21-3.87), acute kidney injury (AKI; pooled OR 1.30, 95% CI 1.19-1.41) and postoperative atrial fibrillation (POAF; pooled OR 1.44, 95% CI 1.05-1.96). Some studies suggested a significant association between preoperative RDW elevation and neurologic complications; however, their number was insufficient for meta-analysis. The postoperative RDW levels were less consistently reported and could not be meta-analyzed. In conclusion, the authors found that elevated preoperative RDW was associated with increased short- and long-term mortality, POAF, and AKI after cardiac surgery. Further research is needed to investigate its role in the risk stratification of patients undergoing cardiac surgery.

Ultrastructural Study of Platelet Behavior and Interrelationship in Sprouting and Intussusceptive Angiogenesis during Arterial Intimal Thickening Formation

Platelets in atherosclerosis, bypass stenosis, and restenosis have been extensively assessed. However, a sequential ultrastructural study of platelets in angiogenesis during the early phases of these lesions has received less attention. Our objective was the study of platelets in angiogenesis and vessel regression during intimal thickening (IT) formation, a precursor process of these occlusive vascular diseases. For this purpose, we used an experimental model of rat occluded arteries and procedures for ultrastructural observation. The results show (a) the absence of platelet adhesion in the de-endothelialized occluded arterial segment isolated from the circulation, (b) that intraarterial myriad platelets contributed from neovessels originated by sprouting angiogenesis from the periarterial microvasculature, (c) the association of platelets with blood components (fibrin, neutrophils, macrophages, and eosinophils) and non-polarized endothelial cells (ECs) forming aggregates (spheroids) in the arterial lumen, (d) the establishment of peg-and-socket junctions between platelets and polarized Ecs during intussusceptive angiogenesis originated from the EC aggregates, with the initial formation of IT, and (e) the aggregation of platelets in regressing neovessels (‘transitory paracrine organoid’) and IT increases. In conclusion, in sprouting and intussusceptive angiogenesis and vessel regression during IT formation, we contribute sequential ultrastructural findings on platelet behavior and relationships, which can be the basis for further studies using other procedures.

Mean platelet volume-to-platelet count ratio after elective cardiac surgical procedures is superior in reflecting platelets metabolic hyperactivity compared to other routine morphological platelet indices: A preliminary report

BACKGROUND

Excessive metabolic excitation of platelets after cardiac procedures may be related to some adverse events but assessment of their metabolic activity is not routine. The purpose of this study was to evaluate which of the basic platelet morphological parameters best reflects their metabolic status.

METHODS

The blood samples of 22cardiac surgical patients (mean age of 62.3 ± 10.3 years) were taken before surgery (BS), and 1, 24 and 48 hours after the operation. Correlations between morphological platelet parameters (platelet count [PLT], mean platelet volume [MPV], platelet distribution width [PDW] and MPV/PLT) and their metabolic activity (total concentration of malondialdehyde [MDA] and MDA/PLT) were estimated.

RESULTS

Significant decline in PLT after operation (from 223 ± 44 × 10¹²/L to 166 ± 57 × 10¹²/L) was accompanied by marked increase in MPV (from 8.4 ± 0.9 fL to 9.1 ± 1.2 fL) and no change of PDW. Consequently, MPV/PLT index increased significantly after procedures from (median with IQR) 0.038 (0.030-0.043) to 0.053 (0.043-0.078). Simultaneously, a significant increase in total platelet MDA content and MDA/PLT was noted reaching peak levels soon after operation. The strongest correlation was observed between MPV/PLT and MDA/PLT (r = 0.56; p < 0.001), although the others were also found to be significant (MDA/PLT vs. MPV; r = 0.35; MDA/PLT vs. PDW; r = 0.34).

CONCLUSIONS

Among basic morphological parameters and indices, the MPV-to-PLT ratio reflects the best metabolic status of platelets in cardiac surgical patients.

The Value of Inflammation Indexes in Predicting Patency of Saphenous Vein Grafts in Patients With Coronary Artery Bypass Graft Surgery

Aim:Our study aimed to investigate the predictive values of inflammation markers in predicting postoperative saphenous vein graft patency in patients who underwent coronary artery bypass grafting (CABG).

Method: We retrospectively analyzed 89 patients who undergone CABG, and 49 patients diagnosed with non-critical coronary artery disease (less than ≤50% stenosis) on coronary angiography were included in the study as a control group. Eighty-nine patients who underwent CABG were divided into two groups according to the presence of 50% or more stenosis in saphenous vein grafts. In these three groups of patients, neutrophil to lymphocyte ratio (NLR), derived NLR (dNLR; neutrophils/white blood cells-neutrophils), platelet to lymphocyte ratio (PLR), lymphocyte to monocyte ratio (LMR), systemic inflammation response index (SIRI; neutrophils × monocytes/lymphocytes), systemic inflammation index (SII; platelet × neutrophil/lymphocyte), and the aggregate index of systemic inflammation (AISI; neutrophil × platelet × monocyte/lymphocyte ratio) were calculated from blood tests. The primary endpoint was more than 50% of saphenous vein stenosis or occlusion, and the aim is to predict this saphenous vein graft disease by inflammation indexes.

Results: The groups were similar in terms of the frequency of stroke, diabetes mellitus, and chronic obstructive pulmonary disease. The frequency of heart failure and hypertension was higher in group 2 (p=0.045, p=0.005), respectively. Multivariate logistic regression analysis showed that LMR and NLR levels were independent predictors of saphenous vein graft disease (SVGD; OR: 0.896; 95%CI: 0.465-0.957; P<0.001) , (OR: 0.592; 95%CI: 0.450-0.875; P=0.034, respectively).The cut-off value of the LMR <2.625 was associated with 78.4% sensitivity and 78% specificity to predict saphenous vein graft disease in patients with CABG.

Conclusion: LMR and NLR may be useful predictors for SVGD.

High mean platelet volume to platelet count ratio as a predictor on poor outcomes after CABG

OBJECTIVES

To determine the effect of mean platelet volume (MPV) to platelet count (PC) ratio on postoperative poor outcomes, early mortality and long-term survival rate in patients undergoing CABG.

METHODS

Between February 2016 and September 2018, all patients undergoing CABG in our department were retrospectively reviewed. A total of 213 consecutive patients were included in the study.

RESULTS

Mean age was 61.5 ± 9.7 years and mean follow-up of all patients was 1.4 ± 0.5 years. All patients were divided into two groups as high and low MPV/PC ratio in terms of 3.825 of cut-off point. 72 patients had a high MPV/PC ratio, whereas, 141 patients had low MPV/PC ratio. The rates of reoperation for early vein-graft occlusion, low cardiac output syndrome and respiratory complication were significantly higher in group 1 (p = 0.03, 0.04 and 0.01). The mean hospital length of stay was higher in group 1 (p = 0.03). MPV/PC ratio for reoperation for early vein-graft occlusion; MPV and ejection fraction for low cardiac output syndrome; hyperlipidemia, chronic renal failure history and MPV/PC ratio for sepsis; male gender, CRF history and CPB time for atrial fibrillation; age, congestive heart failure history, myocardial infarction history and CPB time for the early mortality were found to be independent predictors. Peripheral arterial diseases, USAP and MPV/PC ratio were found to be independent predictors for the late mortality.

CONCLUSIONS

A high MPV/PC ratio is associated with early vein-graft occlusion and poor postoperative outcomes in the early period after CABG. Furthermore, it has a negative effect on late survival.