Recent Developments in Clinical Plasma Proteomics—Applied to Cardiovascular Research

The human plasma proteome mirrors the physiological state of the cardiovascular system, a fact that has been used to analyze plasma biomarkers in routine analysis for the diagnosis and monitoring of cardiovascular diseases for decades. These biomarkers address, however, only a very limited subset of cardiovascular diseases, such as acute myocardial infarct or acute deep vein thrombosis, and clinical plasma biomarkers for the diagnosis and stratification cardiovascular diseases that are growing in incidence, such as heart failure and abdominal aortic aneurysm, do not exist and are urgently needed. The discovery of novel biomarkers in plasma has been hindered by the complexity of the human plasma proteome that again transforms into an extreme analytical complexity when it comes to the discovery of novel plasma biomarkers. This complexity is, however, addressed by recent achievements in technologies for analyzing the human plasma proteome, thereby facilitating the possibility for novel biomarker discoveries. The aims of this article is to provide an overview of the recent achievements in technologies for proteomic analysis of the human plasma proteome and their applications in cardiovascular medicine.

MSC Pretreatment for Improved Transplantation Viability Results in Improved Ventricular Function in Infarcted Hearts

Many clinical studies utilizing MSCs (mesenchymal stem cells, mesenchymal stromal cells, or multipotential stromal cells) are underway in multiple clinical settings; however, the ideal approach to prepare these cells in vitro and to deliver them to injury sites in vivo with maximal effectiveness remains a challenge. Here, pretreating MSCs with agents that block the apoptotic pathways were compared with untreated MSCs. The treatment effects were evaluated in the myocardial infarct setting following direct injection, and physiological parameters were examined at 4 weeks post-infarct in a rat permanent ligation model. The prosurvival treated MSCs were detected in the hearts in greater abundance at 1 week and 4 weeks than the untreated MSCs. The untreated MSCs improved ejection fraction in infarcted hearts from 61% to 77% and the prosurvival treated MSCs further improved ejection fraction to 83% of normal. The untreated MSCs improved fractional shortening in the infarcted heart from 52% to 68%, and the prosurvival treated MSCs further improved fractional shortening to 77% of normal. Further improvements in survival of the MSC dose seems possible. Thus, pretreating MSCs for improved in vivo survival has implications for MSC-based cardiac therapies and in other indications where improved cell survival may improve effectiveness.

PERIODONTITIS AND MYOCARDIAL INFARCTION RISK: A CASE-CONTROL STUDY

Objectives: This study aimed to assess the association of periodontitis and Myocardial Infarction (MI) and contributes as a potential risk factor for its incidence. Methodology: This multi-centre, case-control study enrolled 125 participants. Case group comprising of Acute Myocardial Infarction (AMI) = 55, control group consisting of non – AMI = 70. Both groups were assessed for presence of periodontitis along with specific risk factors that were recorded in a modified proforma comprising of questions pertaining to demographics, oral hygiene practices and oral eating habits. Chi-square test was used to assess association and p-value was considered significant at ≤0.05. Results: Periodontitis was found to be prevalent in 71% of Myocardial Infarction (MI) patients with an OR 4.125 (95% CI, 1.934 - 8.797) as compared to 37% in Control (non-Myocardial Infarct). Increasing age, male gender, illiteracy, unemployment/retirement, low socio-economic status, being overweight, no dental visits, and smoking (both duration & frequency) were found to be statistically significantly associated with occurrence of periodontitis and myocardial infarction in the study. Conclusion: Periodontitis was found to be prevalent among the MI patients suggesting a causal link between these two conditions that can be reduced by adopting a healthy lifestyle, refraining from smoking, good oral hygiene and visiting a dentist for regular check-up.

Prognostic Value of Platelet-Lymphocyte Ratio and High-Density Lipoprotein in Patients with Acute Myocardial Infarct

Acute Myocardial Infarct (AMI) is the main reason for mortality. Platelet to Lymphocyte Ratio (PLR) describesthrombocyte aggregation and inflammation that is linked to cardiovascular disease. High-Density Lipoprotein (HDL) is antiatherogenic.This study aims to analyze the prognostic value of PLR and HDL in patients with AMI. This study was aretrospective observational study by obtaining laboratory results from complete blood count and lipid profiles frominpatients with AMI (STEMI and NSTEMI) medical records during Mei 2019–August 2020. Receiver Operating Characteristics(ROC) analysis was done to get the PLR and HDL cut-off. Prognostic value evaluation was based on sensitivity, specificity,positive and negative predictive value, and accuracy. Results obtained were from 302 subjects with a mean age of 58.4+9.6years old, with most male patients (74.5%). Receiver operating characteristics curve analysis showed an 0.514 Area UnderCurve (AUC) for PLR with p=0.685. High-density lipoprotein ROC was 0.573 with a p=0.033 (p< 0.05), with HDL cut-off = 50.0;sensitivity 72.7%, specificity 32.3%, positive predictive value 63.3%, negative predictive value 42.0% and 57.3% accuracy.Platelet to lymphocyte ratio mean was lower in the HDL <50 group (187.9) compared to the HDL > 50 (210.8), (p=0.009).High-density lipoprotein can be concluded as a potential prognostic factor of acute myocardial infarct. The lower the HDL,the greater the risk for a poor prognosis. A big-scale prospective study should be held to clarify and confirm these findings.

390 Late pleuro-pericardial effusion after atrial fibrillation radiofrequency ablation

Aims Post-cardiac injury syndrome (PCIS) is an inflammatory state involving pericardium, epicardium, and myocardium causing a clinical picture in which epicardial and pericardial symptoms are prevalent. It appears mediated by autoimmune mechanisms and may appear as late post myocardial infarction pericarditis (Dressler’s Syndrome) or as a post traumatic pericarditis in the case of spontaneous thoracic trauma or iatrogenic pericarditis. Apart from the acute setting, pericardial effusion can be a manifestation of PCIS after interventional procedures. Methods and results A 57 years old hypertensive woman suffering from recurrent atrial fibrillation episodes underwent a technically difficult radio-frequency catheter ablation because of complex pulmonary veins anatomy and wide scar in the left atrial wall. During the procedure she developed cardiac tamponade and 410 ml of blood were drained by pericardiocentesis and re-infused without recurrent pericardial effusion during further in-hospital stay. She was discharged on apixaban 5 mg b.i.d. with Hb value of 10.2 g/dl. Two weeks later the patient was hospitalized for worsening cough, atypical chest pain, dyspnoea and modest orthopnea. C-reactive protein levels were 8.7 mg/dl, Hb was 9.9 g/dl and platelet count 484 000/ml; blood cultures were negative. An urgent thoracic CT scan showed bilateral pleural effusion and ubiquitous pericardial effusion (2.5–3 cm), without signs of active bleeding from the cardiac chambers into the pericardium. After stopping apixaban, the patient was given colchicine (1 mg/die). A total of 1200 ml of hematic pericardial fluid was drained from the pericardium over a 5-day period. Autoimmune blood tests were negative, as well as antibodies to pericardiotropic viruses. Pericardial fluid was negative for quantiferon and direct BK. On day 9, the drain was removed and steroidal treatment was started (prednisone 25 mg/die with scheduled tapering). Further echocardiographic exams were stable without pericardial effusion; a chest X-ray scan (at day 16) showed reversal of the water bottle shaped heart and of the pleural effusion. Conclusions Early myocardial infarct-associated pericarditis and Dressler’s syndrome account for about 20% of cases of PCIS accompanied by symptoms of epicardial and pericardial origin. PCIS is quite common after cardiac surgery, but it may be also observed even after iatrogenic trauma occurring during cardiac interventions: PCI, pacemaker lead insertion, radiofrequency ablation and Swan–Ganz catheterization. Blood entering the pericardium is thought to play a pivotal etiological role in iatrogenic PCIS, with consequent huge inflammatory reaction in the mesothelial tissue resulting in clinical manifestations of pericarditis. In animal models of PCIS, systemic release of cardiac antigens and self-antigen specific responses has been hypothesized. In our case cardiac tamponade complicating the ablation procedure probably initiated the epicardial and pericardial inflammatory response. Even if based on few data, the patient was treated with colchicine first, avoiding aspirin because of the hemorrhagic pericardial fluid; glucocorticoids were then started when symptoms and signs of PCIS slowly resolved despite colchicine treatment. The pericardial fluid was hemorrhagic (Hb 5.9 g/dl) and treatment with apixaban, in the context of an inflammatory mesothelial response, could have caused this peculiar, hemorrhagic, pericardial reaction.

Impact of thrombus burden on long-term clinical outcomes in patients with either anterior or non-anterior ST-segment elevation myocardial infarction

Large thrombus burden (LTB) during ST-segment elevation myocardial infarction (STEMI) could translate into worse clinical outcomes. The impact of a LTB in terms of long-term clinical outcomes on different myocardial infarct territories has not yet been fully evaluated. From April 2002 to December 2004, consecutive patients with STEMI undergoing percutaneous coronary intervention with drug eluting stent were evaluated. The study sample was stratified in two groups: anterior STEMI and non-anterior STEMI. LTB was considered as a thrombus larger than or equal to 2-vessel diameters, and small thrombus burden less than 2-vessel diameters. Major adverse cardiac events (MACE) were evaluated at 10-year and survival data were collected up to 15-year. A total of 812 patients were evaluated, 6 patients were excluded due to inadequate angiographic images, 410 (50.9%) had an anterior STEMI and 396 (49.1%) a non-anterior STEMI. Patients with LTB had higher rates of 10-year mortality (aHR 2.27, 95%CI 1.42–3.63; p = 0.001) and 10-year MACE (aHR 1.46, 95%CI 1.03–2.08; p = 0.033) in anterior STEMI, but not in non-anterior STEMI (aHR 0.78, 95%CI 0.49–1.24; p = 0.298; aHR 0.71, 95%CI 0.50–1.02; p = 0.062). LTB was associated with increased 30-day mortality (aHR 5.60, 95%CI 2.49–12.61; p < 0.001) and 30-day MACE (aHR 2.72, 95%CI 1.45–5.08; p = 0.002) in anterior STEMI, but not in non-anterior STEMI (aHR 0.39, 95%CI 0.15–1.06; p = 0.066; aHR 0.67, 95%CI 0.31–1.46; p = 0.316). Beyond 30-day, LTB had no impact on mortality and MACE in both groups. In anterior STEMI, LTB is associated with worse long-term clinical outcomes, this effect was driven by early events.

Sevoflurane Postconditioning Upregulates HIF-1α Pathway Enhances BNIP3 Mediated Mitochondrial Autophagy in Myocardium of Aged Mice

BACKGROUND: Diminished mitochondrial autophagy in aged myocardium may be due to impaired HIF-1α protein expression. Previous studies confirmed that upregulation of HIF-1α expression protects myocardial tissue from ischemia/reperfusion (I/R) injury and found that sevoflurane post-conditioning (SpostC) mediated mitochondrial autophagy plays a significant role in myocardial protection. However, the protective mechanism of SpostC in aged myocardium is unclear. This study aimed to investigate whether SpostC regulates BNIP3 - mediated mitochondrial autophagy by upregulating HIF-1α expression, thus alleviating myocardial I/R injury in aged mice.Methods: An in vivo mouse model of myocardial I/R injury was established and treated with sevoflurane at the time of reperfusion, and at the end of reperfusion, echocardiographic changes, myocardial infarct size, mitochondrial ultrastructure, and autophagosomes were measured, mitochondrial respiratory function and enzyme activity were detected, serum LDH, CKM, CK-MB, TNNT2, IL-6 levels were determined, and Western blot was used to examine the expression levels of phosphorylated HIF-1α, LC3-II, BNIP3, Beclin1, TLR9, and IL-6 protein in myocardial tissue.RESULTS: In young, healthy myocardium, SpostC upregulated the expression of HIF-1α, activated the downstream target gene BNIP3 protein, and upregulated the expression levels of autophagy essential proteins LC3-II, Beclin-1, and TLR9, attenuated myocardial oxidative stress injury, stabilized mitochondrial ultrastructure, inhibited cardiomyocyte apoptosis, and ultimately reduced myocardial infarct size. In aged myocardium, SpostC also played an excellent myocardial protective role.CONCLUSION: SpostC was able to upregulate HIF-1α expression, promote BNIP3-mediated mitochondrial autophagy, reduce myocardial infarct size, and alleviate myocardial I/R injury in aged mice.

Possible Treatment of Myocardial Infarct Based on Tissue Engineering Using a Cellularized Solid Collagen Scaffold Functionalized with Arg-Glyc-Asp (RGD) Peptide

Currently, the clinical impact of cell therapy after a myocardial infarction (MI) is limited by low cell engraftment due to low cell retention, cell death in inflammatory and poor angiogenic infarcted areas, secondary migration. Cells interact with their microenvironment through integrin mechanoreceptors that control their survival/apoptosis/differentiation/migration and proliferation. The association of cells with a three-dimensional material may be a way to improve interactions with their integrins, and thus outcomes, especially if preparations are epicardially applied. In this review, we will focus on the rationale for using collagen as a polymer backbone for tissue engineering of a contractile tissue. Contractilities are reported for natural but not synthetic polymers and for naturals only for: collagen/gelatin/decellularized-tissue/fibrin/Matrigel™ and for different material states: hydrogels/gels/solids. To achieve a thick/long-term contractile tissue and for cell transfer, solid porous compliant scaffolds are superior to hydrogels or gels. Classical methods to produce solid scaffolds: electrospinning/freeze-drying/3D-printing/solvent-casting and methods to reinforce and/or maintain scaffold properties by reticulations are reported. We also highlight the possibility of improving integrin interaction between cells and their associated collagen by its functionalizing with the RGD-peptide. Using a contractile patch that can be applied epicardially may be a way of improving ventricular remodeling and limiting secondary cell migration.