Physiology of pericardial fluid production and drainage

Pericardial fluid troponin in cardiac surgery

BACKGROUND AND OBJECTIVE

Pericardial Fluid (PF) is a rich reservoir of biologically active factors. Due to its proximity to the heart, the biochemical structure of PF may reflect the pathological changes in the cardiac interstitial environment. This manuscript aimed to determine whether the PF level of cardiac troponins changes in patients undergoing cardiac surgery.

METHODS

This scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Medline, EMBASE, Cochrane, ClinicalTrials.gov, and Google Scholar databases were electronically searched for primary studies using the keywords "pericardial fluid," "troponin," and "cardiac surgery." The primary outcome of interest was changes in troponin levels within the PF preoperatively and postoperatively. Secondary outcomes of interest included comparisons between troponin level changes in the PF compared to plasma.

RESULTS

A total of 2901 manuscripts were screened through a title and abstract stage by two independent blinded reviewers. Of those, 2894 studies were excluded, and the remaining seven studies underwent a full-text review. Studies were excluded if they did not provide data or failed to meet inclusion criteria. Ultimately, six articles were included that discussed cardiac troponin levels within the PF in patients who had undergone cardiac surgery. Pericardial troponin concentration increased over time after surgery, and levels were significantly higher in PF compared to serum. All studies found that the type of operation did not affect these overall observations.

CONCLUSION

Our review of the literature suggest that the PF level of cardiac troponins increases in patients undergoing cardiac surgery, irrespective of the procedure type. However, these changes' exact pattern and clinical significance remain undefined.

Spatiotemporal development and the regulatory mechanisms of cardiac resident macrophages: Contribution in cardiac development and steady state

Cardiac resident macrophages (CRMs) are integral components of the heart and play significant roles in cardiac development, steady-state, and injury. Advances in sequencing technology have revealed that CRMs are a highly heterogeneous population, with significant differences in phenotype and function at different developmental stages and locations within the heart. In addition to research focused on diseases, recent years have witnessed a heightened interest in elucidating the involvement of CRMs in heart development and the maintenance of cardiac function. In this review, we primarily concentrated on summarizing the developmental trajectories, both spatial and temporal, of CRMs and their impact on cardiac development and steady-state. Moreover, we discuss the possible factors by which the cardiac microenvironment regulates macrophages from the perspectives of migration, proliferation, and differentiation under physiological conditions. Gaining insight into the spatiotemporal heterogeneity and regulatory mechanisms of CRMs is of paramount importance in comprehending the involvement of macrophages in cardiac development, injury, and repair, and also provides new ideas and therapeutic methods for treating heart diseases.

Accumulation of Inflammatory Mediators in the Normal Pericardial Fluid

There is paucity of studies that focus on the composition of pericardial fluid under resting conditions. The purpose of this study is to determine the levels of inflammatory mediators in pericardial fluid and their correlation with plasma levels in patients undergoing elective cardiac surgery. We conducted a prospective cohort study on candidates for elective aortic valve replacement surgery. Pericardial fluid and peripheral venous blood samples were collected after opening the pericardium. Levels of interleukin 1α (IL-1α); interleukin 1β (IL-1β); interleukin 2 (IL-2) interleukin 4 (IL-4); interleukin 6 (IL-6); interleukin 8 (IL8); interleukin 10 (IL10); tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1 (MCP-1) epidermal growth factor (EGF), soluble E-selectin, L-selectin, P-selectin, intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) were determined in both pericardial fluid and serum samples. A total of 45 patients with a mean age of 74 years were included of which 66% were males. Serum levels of all study mediators were within normal limits. Serum and pericardial levels of IL-1 α, IL-1 β, IL-2, IL-4, and IL-10 were similar. Levels of VEGF, EGF, VCAM-2, ICAM 1, E-selectin, P-selectin, and L-selectin were significantly lower in pericardial fluid than in serum. However, levels of IL-6, IL-8, TNF-α, IFN-γ, MCP-1, and MCP-1 were significantly higher in the pericardial fluid than in serum. Under normal conditions, the pattern of distribution of different inflammatory mediators in the pericardial fluid does not reflect serum levels. This may either reflect the condition of the underlying myocardium and epicardial fat or the activity of the mesothelial and mononuclear cells present in pericardial fluid.

Metabolomics investigation of post-mortem human pericardial fluid

INTRODUCTION

Due to its peculiar anatomy and physiology, the pericardial fluid is a biological matrix of particular interest in the forensic field. Despite this, the available literature has mainly focused on post-mortem biochemistry and forensic toxicology, while to the best of authors' knowledge post-mortem metabolomics has never been applied. Similarly, estimation of the time since death or post-mortem interval based on pericardial fluids has still rarely been attempted.

OBJECTIVES

We applied a metabolomic approach based on 1H nuclear magnetic resonance spectroscopy to ascertain the feasibility of monitoring post-mortem metabolite changes on human pericardial fluids with the aim of building a multivariate regression model for post-mortem interval estimation.

METHODS

Pericardial fluid samples were collected in 24 consecutive judicial autopsies, in a time frame ranging from 16 to 170 h after death. The only exclusion criterion was the quantitative and/or qualitative alteration of the sample. Two different extraction protocols were applied for low molecular weight metabolites selection, namely ultrafiltration and liquid-liquid extraction. Our metabolomic approach was based on the use of 1H nuclear magnetic resonance and multivariate statistical data analysis.

RESULTS

The pericardial fluid samples treated with the two experimental protocols did not show significant differences in the distribution of the metabolites detected. A post-mortem interval estimation model based on 18 pericardial fluid samples was validated with an independent set of 6 samples, giving a prediction error of 33-34 h depending on the experimental protocol used. By narrowing the window to post-mortem intervals below 100 h, the prediction power of the model was significantly improved with an error of 13-15 h depending on the extraction protocol. Choline, glycine, ethanolamine, and hypoxanthine were the most relevant metabolites in the prediction model.

CONCLUSION

The present study, although preliminary, shows that PF samples collected from a real forensic scenario represent a biofluid of interest for post-mortem metabolomics, with particular regard to the estimation of the time since death.

Chronic Pericardial Effusion: Causes and Management

Chronic pericardial effusion is a common pericardial syndrome whose approach has been well standardised in recent years. The main challenge associated with this condition is the progression (sometimes unheralded) to cardiac tamponade. Pericardial effusions may present either as an isolated finding or in the context of a specific etiology including autoimmune, neoplastic, or metabolic disease. Among investigations used during diagnostic work-up, echocardiography is of paramount importance for the diagnosis, sizing, and serial evaluation of the hemodynamic impact of effusions on heart diastolic function. In an individualised manner, advanced imaging including computed tomography and cardiac magnetic resonance imaging should be performed, especially if baseline tests are inconclusive. Triage of these patients according to the most recent 2015 European Society of Cardiology Guidelines for the diagnosis and management of pericardial diseases should take into account the presence of hemodynamic compromise as well as suspicion of malignant or purulent pericarditis as first step, C-reactive protein serum level measurement as second step, investigations for a specific condition known to be associated with pericardial effusion as third step, and finally the size and the duration of the effusion. Treatment depends on the evaluation of the above-mentioned parameters and should ideally be tailored to the individual patient. Prognosis of chronic pericardial effusions depends largely on the underlying etiology. According to novel data, the prognosis of individuals with idiopathic, chronic (> 3 months), large (> 2 cm), asymptomatic pericardial effusions is usually benign and a watchful waiting strategy seems more reasonable and cost-effective than routine drainage as previously recommended.

Cardiac tamponade

Cardiac tamponade is a medical emergency caused by the progressive accumulation of pericardial fluid (effusion), blood, pus or air in the pericardium, compressing the heart chambers and leading to haemodynamic compromise, circulatory shock, cardiac arrest and death. Pericardial diseases of any aetiology as well as complications of interventional and surgical procedures or chest trauma can cause cardiac tamponade. Tamponade can be precipitated in patients with pericardial effusion by dehydration or exposure to certain medications, particularly vasodilators or intravenous diuretics. Key clinical findings in patients with cardiac tamponade are hypotension, increased jugular venous pressure and distant heart sounds (Beck triad). Dyspnoea can progress to orthopnoea (with no rales on lung auscultation) accompanied by weakness, fatigue, tachycardia and oliguria. In tamponade caused by acute pericarditis, the patient can experience fever and typical chest pain increasing on inspiration and radiating to the trapezius ridge. Generally, cardiac tamponade is a clinical diagnosis that can be confirmed using various imaging modalities, principally echocardiography. Cardiac tamponade is preferably resolved by echocardiography-guided pericardiocentesis. In patients who have recently undergone cardiac surgery and in those with neoplastic infiltration, effusive-constrictive pericarditis, or loculated effusions, fluoroscopic guidance can increase the feasibility and safety of the procedure. Surgical management is indicated in patients with aortic dissection, chest trauma, bleeding or purulent infection that cannot be controlled percutaneously. After pericardiocentesis or pericardiotomy, NSAIDs and colchicine can be considered to prevent recurrence and effusive-constrictive pericarditis.

Pericarditis caused by Proteus mirabilis in sheep

Pericarditis means inflammation in the pericardial sac. Pericarditis is divided into three categories based on morphology, including fibrinous, purulent, and constrictive. In the present study, a 7-month-old male Ghezel breed sheep was examined for low weighting rate for three months. Tachypnea, tachycardia, heart friction sound, absence of fever and normal appetite were recorded in the clinical examination. In the patient's history, there was a history of perforated chest trauma behind the left scapula about three months ago. After the echocardiography examination and bacteriology procedures, purulent pericarditis caused by Proteus mirabilis was diagnosed. The bacterium was analysed using genome sequencing and new strain called Abhar114 was diagnosed. This is the first report of pericarditis caused by Proteus mirabilis in sheep.

Dysregulation of metalloproteins in ischemic heart disease patients with systolic dysfunction

Ischemic heart disease (IHD) is the leading cause of mortality worldwide. Metalloproteins have been linked to human health and diseases. The molecular functions of metalloproteins in IHD is not well understood and require further exploration. The objective of this study was to find out the role of metalloproteins in the pericardial fluid of IHD patients having normal (EF > 45) and impaired (EF < 45) left ventricular ejection fraction (LVEF). IHD patients were grouped into two categories: LVEF<45 (n = 12) and LVEF >45 (n = 33). Pooled samples of pericardial fluid were fractionated by using ZOOM-isoelectric focusing (IEF) followed by further processing using one-dimensional gel electrophoresis (1D SDS-PAGE) and filter-aided sample preparation (FASP). Tryptic peptides of each fraction and differential bands were then analyzed by nano-LC-ESI-MS/MS. Protein identification was performed through a Mascot search engine using NCBI-Prot and SwissProt databases. A total of 1082 proteins including 154 metalloproteins were identified. In the differential bands, 60 metalloproteins were identified, while 115 metalloproteins were identified in all ZOOM-IEF fractions. Twelve differentially expressed metalloproteins were selected in the intense bands according to their molecular weight (MW) and isoelectric point (pI). The 12 differentially expressed metalloprotein includes ceruloplasmin, Prothrombin, Vitamin K-dependent protein, Fibulin-1, Ribosomal protein S6 kinase alpha-6, nidogen, partial, Serum albumin, Hemopexin, C-reactive protein, Serum amyloid P-component, and Intelectin-1 protein which were all up-regulated while serotransferrin is the only metalloprotein that was down-regulated in impaired (LVEF<45) group. Among the metalloproteins, Zn-binding proteins are 36.5 % followed by Ca-binging 32.2 %, and Fe-binging 12.2 %. KEGG, pathway analysis revealed the association of ceruloplasmin and serotransferrin with the ferroptosis pathway. In conclusion, 154 metalloproteins were identified of them the Zn-binding protein followed by Ca-binding and Fe-binding proteins were the most abundant metalloproteins. The two metalloproteins, the Cu-binding protein ceruloplasmin, and Fe-binding protein serotransferrin are involved in the ferroptosis pathway, an iron-dependent form of regulated cell death that has been linked to cardiac pathology, especially in IHD patients having impaired systolic (LVEF<45) dysfunction. However, further research is required to validate these findings.

Methods to Measure Water Permeability

Water permeability is a key feature of the cell plasma membranes, and it has seminal importance for several cell functions such as cell volume regulation, cell proliferation, cell migration, and angiogenesis to name a few. The transport of water occurs mainly through plasma membrane water channels, aquaporins. Aquaporins have very important function in physiological and pathophysiological states. Due to the above, the experimental assessment of the water permeability of cells and tissues is necessary. The development of new methodologies of measuring water permeability is a vibrant scientific field that constantly develops during the last three decades along with the advances in imaging mainly. In this chapter we describe and critically assess several methods that have been developed for the measurement of water permeability both in living cells and in tissues with a focus in the first category.

Myeloperoxidase Levels in Pericardial Fluid Is Independently Associated with Postoperative Atrial Fibrillation after Isolated Coronary Artery Bypass Surgery

BACKGROUND

Postoperative atrial fibrillation (POAF) is the most common complication after surgery for atherosclerotic cardiovascular disease (ASCVD) and leads to extended hospital stays and increased mortality. Myeloperoxidase (MPO) in postoperative pericardial drainage fluid is associated with an increased risk of POAF; however, the correlations between MPO in intraoperative pericardial fluid and POAF remain largely unknown. The aim of the study was to evaluate whether MPO is associated with POAF.

METHODS

A total of 97 patients with no history of atrial arrhythmia who had undergone coronary artery bypass surgery (CABG) were identified. We prospectively measured the levels of MPO in intraoperative pericardial fluid and blood using the human magnetic Luminex assay. Then, the occurrence of atrial fibrillation was continuously observed by postoperative ECG and telemetry strips until discharge.

RESULTS

Our data showed that POAF occurred in 24 of 97 patients (24.74%). MPO levels in blood were higher in the POAF group than the SR group (p = 0.064). Patients with POAF had significantly higher intraoperative pericardial fluid MPO levels than patients who remained in SR (p = 0.021). There was no significant correlation between pericardial fluid MPO levels and blood MPO levels (r = -0.47, p = 0.770). In a multivariable logistic regression model, pericardial fluid MPO levels were significantly associated with a higher risk of POAF (odds ratio = 1.016, 95% confidence interval, 1.001-1.031; p = 0.031).

CONCLUSIONS

Higher intraoperative pericardial fluid MPO levels are linked with POAF in patients undergoing CABG. This finding provides insight into a possible mechanism of MPO in pericardial fluid increase susceptibility to developing POAF in patients undergoing CABG.

Intrapericardial Exosome Therapy Dampens Cardiac Injury via Activating Foxo3

BACKGROUND

Mesenchymal stem cell (MSC)-derived exosomes are well recognized immunomodulating agents for cardiac repair, while the detailed mechanisms remain elusive. The Pericardial drainage pathway provides the heart with immunosurveillance and establishes a simplified model for studying the mechanisms underlying the immunomodulating effects of therapeutic exosomes.

METHODS

Myocardial infarction (MI) models with and without pericardiectomy (corresponding to Tomy MI and NonTomy MI) were established to study the functions of pericardial drainage pathway in immune activation of cardiac-draining mediastinal lymph node (MLN). Using the NonTomy MI model, MSC exosomes or vehicle PBS was intrapericardially injected for MI treatment. Via cell sorting and RNA-seq (RNA-sequencing) analysis, the differentially expressed genes were acquired for integrated pathway analysis to identify responsible mechanisms. Further, through functional knockdown/inhibition studies, application of cytokines and neutralizing antibodies, western blot, flow cytometry, and cytokine array, the molecular mechanisms were studied. In addition, the therapeutic efficacy of intrapericardially injected exosomes for MI treatment was evaluated through functional and histological analyses.

RESULTS

We show that the pericardial draining pathway promoted immune activation in the MLN following MI. Intrapericardially injected exosomes accumulated in the MLN and induced regulatory T cell differentiation to promote cardiac repair. Mechanistically, uptake of exosomes by major histocompatibility complex (MHC)-II+ antigen-presenting cells (APCs) induced Foxo3 activation via the protein phosphatase (PP)-2A/p-Akt/forkhead box O3 (Foxo3) pathway. Foxo3 dominated APC cytokines (IL-10, IL-33, and IL-34) expression and built up a regulatory T cell (Treg)-inducing niche in the MLN. The differentiation of Tregs as well as their cardiac deployment were elevated, which contributed to cardiac inflammation resolution and cardiac repair.

CONCLUSIONS

This study reveals a novel mechanism underlying the immunomodulation effects of MSC exosomes and provides a promising candidate (PP2A/p-Akt/Foxo3 signaling pathway) with a favorable delivery route (intrapericardial injection) for cardiac repair.

Effect of hyperglycemia on tbx5a and nppa gene expression and its correlation to structural and functional changes in developing zebrafish heart

The objective of the current study is to analyze the effects of gestational diabetes on structural and functional changes in correlation with these two essential regulators of developing hearts in vivo using zebrafish embryos. We employed fertilized zebrafish embryos exposed to a hyperglycemic condition of 25 mM glucose for 96 h postfertilization. The embryos were subjected to various structural and functional analyses in a time-course manner. The data showed that exposure to high glucose significantly affected the embryo's size, heart length, heart rate, and looping of the heart compared to the control. Further, we observed an increased incidence of ventricular standstill and valvular regurgitation with a marked reduction of peripheral blood flow in the high glucose-exposed group compared to the control. In addition, the histological data showed that the high-glucose exposure markedly reduced the thickness of the wall and the number of cardiomyocytes in both atrium and ventricles. We also observed striking alterations in the pericardium like edema, increase in diameter with thinning of the wall compared to the control group. Interestingly, the expression of tbx5a and nppa was increased in the early development and found to be repressed in the later stage of development in the hyperglycemic group compared to the control. In conclusion, the developing heart is more susceptible to hyperglycemia in the womb, thereby showing various developmental defects possibly by altering the expression of crucial gene regulators such as tbx5a and nppa.

Non-invasive characterization of pleural and pericardial effusions using T1 mapping by magnetic resonance imaging

AIMS

Differentiating exudative from transudative effusions is clinically important and is currently performed via biochemical analysis of invasively obtained samples using Light's criteria. Diagnostic performance is however limited. Biochemical composition can be measured with T1 mapping using cardiovascular magnetic resonance (CMR) and hence may offer diagnostic utility for assessment of effusions.

METHODS AND RESULTS

A phantom consisting of serially diluted human albumin solutions (25-200 g/L) was constructed and scanned at 1.5 T to derive the relationship between fluid T1 values and fluid albumin concentration. Native T1 values of pleural and pericardial effusions from 86 patients undergoing clinical CMR studies retrospectively analysed at four tertiary centres. Effusions were classified using Light's criteria where biochemical data was available (n = 55) or clinically in decompensated heart failure patients with presumed transudative effusions (n = 31). Fluid T1 and protein values were inversely correlated both in the phantom (r = -0.992) and clinical samples (r = -0.663, P < 0.0001). T1 values were lower in exudative compared to transudative pleural (3252 ± 207 ms vs. 3596 ± 213 ms, P < 0.0001) and pericardial (2749 ± 373 ms vs. 3337 ± 245 ms, P < 0.0001) effusions. The diagnostic accuracy of T1 mapping for detecting transudates was very good for pleural and excellent for pericardial effusions, respectively [area under the curve 0.88, (95% CI 0.764-0.996), P = 0.001, 79% sensitivity, 89% specificity, and 0.93, (95% CI 0.855-1.000), P < 0.0001, 95% sensitivity; 81% specificity].

CONCLUSION

Native T1 values of effusions measured using CMR correlate well with protein concentrations and may be helpful for discriminating between transudates and exudates. This may help focus the requirement for invasive diagnostic sampling, avoiding unnecessary intervention in patients with unequivocal transudative effusions.

Chronic pericardial effusion: current concepts and emerging trends

INTRODUCTION

Pericardial effusion (PEF) is a common and challenging pericardial syndrome with a variety of clinical manifestations ranging from asymptomatic, incidentally uncovered small PEFs, to life-threatening cardiac tamponade.

AREAS COVERED

: This review focuses on the pathophysiology, epidemiology, etiology, classification, clinical findings, diagnostic work-up, management and outcome of PEFs. Particular emphasis has been given on the most recent evidence concerning the contribution of imaging for the detection, differential diagnosis and evaluation of the hemodynamic impact of PEFs on the diastolic filling of the heart. Moreover, simplified algorithms for PEF triage and management have been included.

EXPERT OPINION

The management of patients with PEFs is mainly based on four parameters namely hemodynamic impact on diastolic function, elevation of inflammatory markers, presence of a specific underlying condition known to be associated with PEF and finally size and duration of the effusion. Novel data have contributed to change our view towards large, asymptomatic, "idiopathic" PEFs and dictated a rather conservative approach in most cases. It is also stressed that there is a compelling need for additional research, which is essential for tailored treatments aiming at the improvement of quality of life and containment of health care costs.

Left hemothorax resulting from delayed right ventricular apical pacing lead perforation without hemopericardium, a case report

INTRODUCTION AND IMPORTANCE

Right ventricular pacemaker lead perforation is a rare but well documented complication of pacemaker implantation. Lead perforation can cause an array of symptoms ranging from none to hemodynamic instability and tamponade. In previously reported cases, lead perforation has always been able to be confirmed by imaging, with computed tomography (CT) scan considered to be the gold standard diagnostic imaging modality.

CASE PRESENTATION

An 80-year-old male underwent uncomplicated implantation of a dual chamber pacemaker for sick sinus syndrome as an outpatient. Thirty-nine days later, the patient presented to the emergency department complaining of new-onset, left-sided, pleuritic chest pain. He was found to have unilateral hemothorax and abnormal pacemaker lead interrogation. Pacemaker lead perforation was suspected but not confirmed with imaging. Lead perforation was only identified after surgical exploration.

CLINICAL DISCUSSION

This patient had multiple risk factors for pacemaker lead perforation. However, imaging, including CT scan was unable to confirm perforation. The presence of an otherwise unexplained left hemothorax strongly suggested that surgical intervention was indicated. The lead perforation was subsequently confirmed with subxiphoid exploration of the pericardial space. The mechanism of lead perforation resulting in hemothorax in this case is not straight forward, as no direct communication between the pericardial and pleural spaces was identified. However, previously described visceral pericardial self-sealing may contribute to the small pericardial accumulation described herein.

CONCLUSION

This patient's presentation and clinical course underscore the importance of maintaining a high index of suspicion for pacemaker lead perforation despite a lack of confirmation with imaging.

Prediction of cardiac events following concurrent chemoradiation therapy for non-small-cell lung cancer using FDG PET

OBJECTIVE

No imaging biomarkers are available for the prediction of cardiac events following concurrent chemoradiation therapy (CCRT) for non-small-cell lung cancer (NSCLC). We evaluated whether F-18 fluorodeoxyglucose positron emission tomography (FDG PET) early after CCRT, in addition to cardiac dosimetry, could predict late cardiac events in NSCLC.

METHODS

We retrospectively enrolled 133 consecutive patients with locally advanced, unresectable stage III NSCLC, who underwent FDG PET early after CCRT and survived at least 6 months. The primary endpoint was cardiac event ≥ grade 2 according to the Common Terminology Criteria for Adverse Events (version 5.0). Myocardial FDG uptake was measured and its association with the risk of cardiac events was evaluated.

RESULTS

FDG PET was performed after a median interval of 11 days of completing CCRT. Overall, 42 (32%) patients experienced cardiac events during a median follow-up of 45 months. The mean heart dose, maximum left ventricular (LV) standardized uptake value (SUV), changes in maximum and mean LV SUV, right ventricular uptake, tumor stage, white blood cell count, and diabetes were associated with cardiac events in univariable analysis. In multivariable analysis, maximum LV SUV (cutoff > 12.84; hazard ratio [95% confidence interval] = 2.140 [1.140-4.016]; p = 0.018) was an independent predictor of cardiac events along with the mean heart dose (> 11.1 Gy; 3.646 [1.792-7.417]; p < 0.001) and tumor stage (IIIB; 1.986 [1.056-3.734]; p = 0.033). It remained predictive of cardiac events in those with higher mean heart dose but not in those with lower mean heart dose.

CONCLUSIONS

Early FDG PET after CCRT for NSCLC could aid in predicting late cardiac events, especially in patients with higher mean heart dose.

Physiology, pathology and the biomolecular corona: the confounding factors in nanomedicine design

The biomolecular corona that forms on nanomedicines in different physiological and pathological environments confers a new biological identity. How the recipient biological system's state can potentially affect nanomedicine corona formation, and how this can be modulated, remains obscure. With this perspective, this review summarizes the current knowledge about the content of biological fluids in various compartments and how they can be affected by pathological states, thus impacting biomolecular corona formation. The content of representative biological fluids is explored, and the urgency of integrating corona formation, as an essential component of nanomedicine designs for effective cargo delivery, is highlighted.

Use of Combination of Oral Levothyroxine and Liothyronine in Severe Hypothyroidism With Massive Pericardial Effusion

Thyroid hormone plays an important role in cardiovascular function. Pericardial effusions are commonly seen in cases of severe hypothyroidism. However, large to massive pericardial effusions with cardiac tamponade are exceptionally rare. Herein, we present two cases of severe hypothyroidism with massive pericardial effusion. Our first case demonstrates that a patient with large pericardial effusion can be managed conservatively with aggressive thyroid hormone replacement therapy. In our second case, pericardiocentesis was performed in addition to thyroid hormone replacement therapy as the underlying aetiology of effusion could not be reasonably limited to hypothyroidism. These two cases served to highlight and demonstrate rapid normalisation of thyroid function test by using aggressive oral thyroid hormone replacement therapy using liothyronine, in combination with levothyroxine, which led to resolution of pericardial effusion and prevent its re-accumulation.

The epicardial delivery of cardiosphere derived cells or their extracellular vesicles is safe but of limited value in experimental infarction

The epicardial administration of therapeutics via the pericardial sac offers an attractive route, since it is minimally invasive and carries no risks of coronary embolization. The aim of this study was to assess viability, safety and effectiveness of cardiosphere-derived cells (CDCs), their extracellular vesicles (EVs) or placebo administered via a mini-thoracotomy 72 h after experimental infarction in swine. The epicardial administration was completed successfully in all cases in a surgery time (knife-to-skin) below 30 min. No significant differences between groups were found in cardiac function parameters evaluated using magnetic resonance imaging before therapy and at the end of the study, despite a trend towards improved function in CDC-treated animals. Moreover, infarct size at 10 weeks was smaller in treated animals, albeit not significantly. Arrhythmia inducibility did not differ between groups. Pathological examination showed no differences, nor were there any pericardial adhesions evidenced in any case 10 weeks after surgery. These results show that the epicardial delivery of CDCs or their EVs is safe and technically easy 3 days after experimental myocardial infarction in swine, but it does not appear to have any beneficial effect on cardiac function. Our results do not support clinical translation of these therapies as implemented in this work.

Rare association of severe iron-deficiency anaemia and moderate pericardial effusion

Pericardial effusion secondary to isolated severe iron-deficiency anaemia is an extremely rare condition. We present a case with severe anaemia presented with moderate pericardial effusion. Pericardial effusion completely resolved with correction of anaemia.

Primer on Pulsed Electrical Field Ablation: Understanding the Benefits and Limitations

Pulsed electrical field (PEF) energy is a promising technique for catheter ablation of cardiac arrhythmias. In this article, the key aspects that need to be considered for safe and effective PEF delivery are reviewed, and their impact on clinical feasibility is discussed. The most important benefit of PEF appears to be the ability to kill cells through mechanisms that do not alter stromal proteins, sparing sensitive structures to improve safety, without sacrificing cardiomyocyte ablation efficacy. Many parameters affect PEF treatment outcomes, including pulse intensity, waveform shape, and number of pulses, as well as electrode configuration and geometry. These physical and electrical characteristics must be titrated carefully to balance target tissue effects with collateral implications (muscle contraction, temperature rise, risk of electrical arcing events). It is important to note that any combination of parameters affecting PEF needs to be tested for clinical efficacy and safety. Applying PEF clinically requires knowledge of the fundamentals of this technology to exploit its opportunities and generate viable, durable health improvements for patients.

Ischemic heart disease: Cellular and molecular immune contributions of the pericardium

Ischemic heart disease promotes complex inflammatory and remodeling pathways which contribute to the development of chronic heart failure. Although blood-derived and local cardiac mediators have traditionally been linked with these processes, the pericardial space has more recently been noted as alternative contributor to the injury response in the heart. The pericardial space contains fluid rich in physiologically active mediators, and immunologically active adipose tissue, which are altered during myocardial infarction. Key immune cells in the pericardial fluid and adipose tissue have been identified which act as mediators for cell recruitment and function after myocardial infarction have been identified in experimental models. Here, we provide an overview of the current understanding of the inflammatory mechanisms of the pericardial space and their role in post-myocardial infarction remodeling and the potential for the use of the pericardial space as a delivery vehicle for treatments to modulate heart healing.

Pericardial fluid and vascular tissue engineering: A preliminary study

BACKGROUND

The heart is surrounded by a membrane called pericardium or pericardial cavity.

OBJECTIVE

In this study, we investigated the pericardial fluid (PF) for coating polycaprolactone (PCL) scaffolds. PFS, which is a PF component, was used for the coating material. In addition to using PFS for surface coating, MED and fetal bovine serum (FBS) were also used for comparison.

METHODS

Pericardial fluid cells (PFSc) isolated from PF were cultured on coated PCL scaffolds for 1, 3, and 5 days. Cell viability was determined using 3-(4, 5-di-methylthiazol- 2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay.

RESULTS

The MTT assay results showed that the viability of cells on PCL scaffold coated with PFS increased over time (P < 0.005), and cell viability was significantly different between PCL scaffolds coated with PFS and non-coated PCL scaffolds. However, cell viability was significantly higher in the PCL scaffolds coated with PFS than non-coated and coated with FBS, MED, and PCL scaffolds. Scanning electron microscopy (SEM) microscopy images and MTT assay indicated that PFSc are attached, proliferated, and spread on PCL scaffolds, especially on PCL scaffolds coated with PFS.

CONCLUSIONS

These results suggest that PFS is a biocompatible material for surface modification of PCL scaffolds, which can be used as a suitable material for tissue engineering applications.

Pathological Findings of Canine Idiopathic Pericarditis and Pericardial Mesotheliomas: Correlation with Clinical and Survival Data

Idiopathic pericarditis (IP) and pericardial mesothelioma (PM) are causes of pericardial effusion in dogs. Pericardiectomy can be a definitive treatment in the case of idiopathic pericardial effusion or a short-term intervention for mesothelioma. The aim of the present study was to investigate which histopathologic parameters are correlated with clinical outcomes in a cohort of dogs that underwent pericardiectomy. The histopathological findings of 22 IPs and 5 PMs were compared with clinical and survival data and the immunohistochemical characterization of immune cells (CD3, CD79α, Iba1). In IP, the mesothelium was lost in 20 cases, reactive in 9, atypical in 3, and mesothelial papillary hyperplasia (MPH) was observed in 4 cases. Numerous macrophages were found in both IPs and PMs especially at the superficial layer of the pericardium. T lymphocytes were observed in mild to moderate numbers and were more numerous than B lymphocytes in both IPs and PMs. MPH was correlated with the quantity of lymphoplasmacytic infiltrate in the superficial layer, inversely related to the thickness of the pericardium, and associated with a longer overall survival. Pericardial fibrosis was present in 19 out of 22 IPs and in all mesotheliomas and was correlated with increased time from initial presentation and pericardiectomy and lymphoplasmacytic infiltrate in the deep zone. Pericardial thickness was correlated with the amount of lymphoplasmacytic and macrophagic infiltrate in the deep zone. Mesothelioma was associated with an increased number of pericardiocentesis procedures before pericardiectomy and with the presence of macrophages in the superficial pericardial layer, edema, fibrin, and hemorrhage. Disease-free interval and overall survival were significantly shorter in patients with mesothelioma compared with IP.

New Approaches to Management of Pericardial Effusions

Purpose of Review

Pericardial effusion is a challenging pericardial syndrome and a cause of serious concern for physicians and patients due to its potential progression to life-threatening cardiac tamponade. In this review, we summarize the contemporary evidence of the etiology; diagnostic work-up, with particular emphasis on the contribution of multimodality imaging; therapeutic options; and short- and long-term outcomes of these patients.

Recent Findings

In recent years, an important piece of information has contributed to put together several missing parts of the puzzle of pericardial effusion. The most recent 2015 guidelines of the European Society of Cardiology for the diagnosis and management of pericardial diseases are a valuable aid for a tailored approach to this condition. Actually, current guidelines suggest a 4-step treatment algorithm depending on the presence or absence of hemodynamic impairment; the elevation of inflammatory markers; the presence of a known or first-diagnosed underlying condition, possibly related to pericardial effusion; and finally the duration and size of the effusion. In contrast to earlier perceptions, based on the most recent evidence, it seems that in the subgroup of asymptomatic patients with large (> 2-cm end-diastolic diameter), chronic (> 3 months) C-reactive protein negative, idiopathic (without an apparent cause) pericardial effusion, a conservative approach is the most reasonable option.

Summary

At present there is an increasing interest in the pericardial syndromes in general and pericardial effusions in specific, which has consistently expanded our knowledge in this “hazy landscape.” Apart from general recommendations applied to all cases, an individualized, etiologically driven treatment is of paramount importance.

Targeted delivery of therapeutic agents to the heart

For therapeutic materials to be successfully delivered to the heart, several barriers need to be overcome, including the anatomical challenges of access, the mechanical force of the blood flow, the endothelial barrier, the cellular barrier and the immune response. Various vectors and delivery methods have been proposed to improve the cardiac-specific uptake of materials to modify gene expression. Viral and non-viral vectors are widely used to deliver genetic materials, but each has its respective advantages and shortcomings. Adeno-associated viruses have emerged as one of the best tools for heart-targeted gene delivery. In addition, extracellular vesicles, including exosomes, which are secreted by most cell types, have gained popularity for drug delivery to several organs, including the heart. Accumulating evidence suggests that extracellular vesicles can carry and transfer functional proteins and genetic materials into target cells and might be an attractive option for heart-targeted delivery. Extracellular vesicles or artificial carriers of non-viral and viral vectors can be bioengineered with immune-evasive and cardiotropic properties. In this Review, we discuss the latest strategies for targeting and delivering therapeutic materials to the heart and how the knowledge of different vectors and delivery methods could successfully translate cardiac gene therapy into the clinical setting.

An overview of human pericardial space and pericardial fluid

The pericardium is a double-layered fibro-serous sac that envelops the majority of the surface of the heart as well as the great vessels. Pericardial fluid is also contained within the pericardial space. Together, the pericardium and pericardial fluid contribute to a homeostatic environment that facilitates normal cardiac function. Different diseases and procedural interventions may disrupt this homeostatic space causing an imbalance in the composition of immune mediators or by mechanical stress. Inflammatory cells, cytokines, and chemokines are present in the pericardial space. How these specific mediators contribute to different diseases is the subject of debate and research. With the advent of highly specialized assays that can identify and quantify various mediators we can potentially establish specific and sensitive biomarkers that can be used to differentiate pathologies, and aid clinicians in improving clinical outcomes for patients.

Sterile Injury Repair and Adhesion Formation at Serosal Surfaces

Most multicellular organisms have a major body cavity containing vital organs. This cavity is lined by a mucosa-like serosal surface and filled with serous fluid which suspends many immune cells. Injuries affecting the major body cavity are potentially life-threatening. Here we summarize evidence that unique damage detection and repair mechanisms have evolved to ensure immediate and swift repair of injuries at serosal surfaces. Furthermore, thousands of patients undergo surgery within the abdominal and thoracic cavities each day. While these surgeries are potentially lifesaving, some patients will suffer complications due to inappropriate scar formation when wound healing at serosal surfaces defects. These scars called adhesions cause profound challenges for health care systems and patients. Therefore, reviewing the mechanisms of wound repair at serosal surfaces is of clinical importance. Serosal surfaces will be introduced with a short embryological and microanatomical perspective followed by a discussion of the mechanisms of damage recognition and initiation of sterile inflammation at serosal surfaces. Distinct immune cells populations are free floating within the coelomic (peritoneal) cavity and contribute towards damage recognition and initiation of wound repair. We will highlight the emerging role of resident cavity GATA6+ macrophages in repairing serosal injuries and compare serosal (mesothelial) injuries with injuries to the blood vessel walls. This allows to draw some parallels such as the critical role of the mesothelium in regulating fibrin deposition and how peritoneal macrophages can aggregate in a platelet-like fashion in response to sterile injury. Then, we discuss how serosal wound healing can go wrong, causing adhesions. The current pathogenetic understanding of and potential future therapeutic avenues against adhesions are discussed.

Access routes, devices and guidance methods for intrapericardial delivery in cardiac conditions

Drug deposition into the intrapericardial space is favourable for achieving localised effects and targeted cardiac delivery owing to its proximity to the myocardium as well as facilitating optimised pharmacokinetic profiles and a reduction in systemic side effects. Access to the pericardium requires invasive procedures but the risks associated with this have been reduced with technological advances, such as combining transatrial and subxiphoid access with different guidance methods. A variety of introducer devices, ranging from needles to loop-catheters, have also been developed and validated in pre-clinical studies investigating intrapericardial delivery of therapeutic agents. Access techniques are generally well-tolerated, self-limiting and safe, although some rare complications associated with certain approaches have been reported. This review covers these access techniques and how they have been applied to the delivery of drugs, cells, and biologicals, demonstrating the potential of intrapericardial delivery for treatments in cardiac arrhythmia, vascular damage, and myocardial infarction.

Different Expressions of Pericardial Fluid MicroRNAs in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy and Ischemic Heart Disease Undergoing Ventricular Tachycardia Ablation

Introduction: Pericardial fluid is enriched with biologically active molecules of cardiovascular origin including microRNAs. Investigation of the disease-specific extracellular microRNAs could shed light on the molecular processes underlying disease development. Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart disease characterized by life-threatening arrhythmias and progressive heart failure development. The current data about the association between microRNAs and ARVC development are limited.

Methods and Results: We performed small RNA sequence analysis of microRNAs of pericardial fluid samples obtained during transcutaneous epicardial access for ventricular tachycardia (VT) ablation of six patients with definite ARVC and three post-infarction VT patients. Disease-associated microRNAs of pericardial fluid were identified. Five microRNAs (hsa-miR-1-3p, hsa-miR-21-5p, hsa-miR-122-5p, hsa-miR-206, and hsa-miR-3679-5p) were found to be differentially expressed between patients with ARVC and patients with post-infarction VT. Enrichment analysis of differentially expressed microRNAs revealed their close linkage to cardiac diseases.

Conclusion: Our data extend the knowledge of pericardial fluid microRNA composition and highlight five pericardial fluid microRNAs potentially linked to ARVC pathogenesis. Further studies are required to confirm the use of pericardial fluid RNA sequencing in differential diagnosis of ARVC.

Minimally invasive delivery of therapeutic agents by hydrogel injection into the pericardial cavity for cardiac repair

Cardiac patches are an effective way to deliver therapeutics to the heart. However, such procedures are normally invasive and difficult to perform. Here, we develop and test a method to utilize the pericardial cavity as a natural "mold" for in situ cardiac patch formation after intrapericardial injection of therapeutics in biocompatible hydrogels. In rodent models of myocardial infarction, we demonstrate that intrapericardial injection is an effective and safe method to deliver hydrogels containing induced pluripotent stem cells-derived cardiac progenitor cells or mesenchymal stem cells-derived exosomes. After injection, the hydrogels form a cardiac patch-like structure in the pericardial cavity, mitigating immune response and increasing the cardiac retention of the therapeutics. With robust cardiovascular repair and stimulation of epicardium-derived cells, the delivered therapeutics mitigate cardiac remodeling and improve cardiac functions post myocardial infarction. Furthermore, we demonstrate the feasibility of minimally-invasive intrapericardial injection in a clinically-relevant porcine model. Collectively, our study establishes intrapericardial injection as a safe and effective method to deliver therapeutic-bearing hydrogels to the heart for cardiac repair.

Contemporary management of pericardial effusion

Pericardial effusion is a relatively common clinical condition with a variety of clinical manifestations ranging from incidentally discovered asymptomatic cases to life-threatening cardiac tamponade. The etiology encompasses idiopathic cases and forms secondary to different conditions, including autoimmune diseases, malignancies, metabolic disorders, etc. While medical therapy should be offered to patients with elevation of inflammatory markers, in specific forms treatment should be appropriate to the underlying disorder. In cases with hemodynamic compromise pericardial drainage either with pericardiocentesis or pericardial "window" is indicated for therapeutic and diagnostic purposes. In the remainder, factors like comorbidities, size and location of the pericardial effusion will influence the clinical decision making. In asymptomatic or minimally symptomatic chronic large idiopathic pericardial effusions, according to recent evidence, a conservative approach with watchful waiting seems the most reasonable option. The prognosis of pericardial effusions largely depends on the underlying etiologies. Metastatic spread to the pericardium has an ominous prognosis whereas large to moderate effusions have been often associated with known or newly discovered specific underlying causes. Chronic small idiopathic effusions have an excellent prognosis and do not require specific monitoring. Large chronic idiopathic effusions in clinically stable patients require a 3 to 6-month assessment ideally in a specialized unit.

Myxoedematous tamponade as initial presentation of Hashimoto's thyroiditis

Cardiac tamponade as the initial presentation of hypothyroidism is extremely rare. We report the case of a 48-year-old man admitted for acute respiratory distress, with cardiac ultrasound showing compressive pericardial effusion. Percutaneous pericardiocentesis was performed leading to a rapid clinical improvement. Laboratory tests confirmed severe hypothyroidism related to Hashimoto's disease. Despite hormone replacement therapy, pericardial effusion recurred after 3 weeks, requiring surgical drainage. Pericardial histology highlighted slight chronic fibrous pericarditis. The cardiac ultrasound scan performed 4 months later showed a well-tolerated chronic pericardial effusion. In conclusion, hypothyroidism should be suspected in case of cardiac tamponade especially in the absence of tachycardia, or in winter when myxoedema is prone to decompensation. Prognosis is generally good under hormone replacement therapy but ultrasound monitoring should be carried out at least until euthyroidism is achieved.

Pericardial fluid proteomic label-free quantification of differentially expressed proteins in ischemic heart disease patients with systolic dysfunction by nano-LC-ESI-MS/MS analysis

Left ventricular systolic dysfunction (LVSD) is common in patients with pre-existing ischemic heart disease (IHD) and myocardial infarction. An untargeted proteomic approach is used to improve the understanding of the molecular mechanisms associated with LVSD and to find out potential proteomic signatures in pericardial fluid. The pericardial fluid of IHD (n = 45) patients was grouped into two categories according to the left ventricular ejection fraction, LVEF ≥45 (n = 33) and LVEF <45 (n = 12), and analyzed by using nano-liquid chromatography-mass spectrometry (nano-LC-MS/MS) technique. The nano-LC-MS/MS analysis resulted in the identification of 709 pericardial fluid (PF) proteins in both normal and impaired systolic functional groups (LVEF ≥45 vs. LVEF <45). Sixteen proteins were found to be differentially expressed (p < 0.05, fold change >2) including 12 down-regulated and 4 up-regulated in the impaired systolic functional group (LVEF <45) compared to the normal group (LVEF ≥45). Among the differentially expressed proteins the inflammatory marker albumin, atherosclerosis marker apolipoprotein A-IV and hedgehog-interacting protein marker of angiogenesis were predominantly associated with the impaired LVEF <45 group. KEGG pathway analysis revealed that the hedgehog (Hh) signalling pathway is up-regulated in LVSD reflecting the underlying molecular and pathophysiological processes.

Local IGF Bioactivity Associates with High PAPP-A Activity in the Pericardial Cavity of Cardiovascular Disease Patients

OBJECTIVE

Pregnancy-associated plasma protein-A (PAPP-A) has been suggested as a proatherogenic enzyme by its ability to locally increase insulin-like growth factor (IGF) activity through proteolytic cleavage of IGF binding protein-4 (IGFBP-4). Recently, stanniocalcin-2 (STC2) was discovered as an inhibitor of PAPP-A. This study aimed to investigate IGFBP-4, PAPP-A, and STC2 as local regulators of IGF bioactivity in the cardiac microenvironment by comparing levels in the pericardial fluid with those in the circulation of patients with cardiovascular disease.

METHODS

Plasma and pericardial fluid were obtained from 39 patients undergoing elective cardiothoracic surgery, hereof 15 patients with type 2 diabetes. Concentrations of IGF-I, intact and fragmented IGFBP-4, PAPP-A, and STC2 were determined by immunoassays and IGF bioactivity by a cell-based assay.

RESULTS

In pericardial fluid, the concentrations of total IGF-I, intact IGFBP-4, and STC2 were 72 ± 10%, 91 ± 5%, and 40 ± 24% lower than in plasma, while PAPP-A was 15 times more concentrated. The levels of the 2 IGFBP-4 fragments generated by PAPP-A and reflecting PAPP-A activity were elevated by more than 25%. IGF bioactivity was 62 ± 81% higher in the pericardial fluid than plasma. Moreover, pericardial fluid levels of both IGFBP-4 fragments correlated with the concentration of PAPP-A and with the bioactivity of IGF. All protein levels were similar in pericardial fluid from nondiabetic and diabetic subjects.

CONCLUSIONS

PAPP-A increases IGF bioactivity by cleavage of IGFBP-4 in the pericardial cavity of cardiovascular disease patients. This study provides evidence for a distinct local activity of the IGF system, which may promote cardiac dysfunction and coronary atherosclerosis.

Ionomic profiling of pericardial fluid in ischemic heart disease

Metals are essential cofactors that play a crucial role in heart function at the cell and tissue level. Information regarding the role of metals in the pericardial fluid and its ionome in ischemic heart disease (IHD) is limited. We aimed to determine the association of elements in pericardial fluid and serum samples of IHD patients and their correlation with systolic and diastolic function. IHD patients have been studied with systolic and diastolic dysfunction categorized on the basis of echocardiographic parameters. We measured concentrations of sixteen elements in the pericardial fluid and serum of 46 patients obtained during open heart surgery with IHD by ICP-MS. The levels of chromium and nickel in pericardial fluid were significantly higher as compared with serum samples of IHD patients (p < 0.05). The chromium, nickel and manganese levels in pericardial fluid were lower in patients with ejection fraction (EF) < 45% as compared to EF > 45% (p < 0.05). There was no significant difference in pericardial concentrations of elements in diastolic dysfunction grade 0-1 with 2 in IHD patients. We also found that decreased concentration of these elements in pericardial fluid is associated with decreased systolic function. These results suggest that pericardial fluid concentrations of these metals may reflect the extent of ischemic heart disease. These findings are hypothesis generating with regards to a role in the pathogenesis of the disorder.

Effect of pericardial incision on left ventricular morphology and systolic function in patients during coronary artery bypass grafting

Background

Accurate assessment of left ventricular (LV) systolic function is important after coronary artery bypass grafting (CABG). LV ejection fraction (LVEF) is conventionally used to evaluate LV systolic function; deformation parameters can be used to detect subtle LV systolic dysfunction. It is unclear whether an incised pericardium without sutures during CABG could affect LV morphology and function. We investigated the effect of pericardial incision on LV morphology and systolic function during CABG.

Methods

Intraoperative transesophageal echocardiography was performed in 27 patients during elective off-pump beating heart CABG 5 min before and after pericardial incision. LV longitudinal and mid-cavity transversal diameters, sphericity index, volumes, and LVEF were measured. LV global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), and twist obtained by two-dimensional speckle tracking echocardiography were measured simultaneously.

Results

LV mid-cavity transversal diameter increased, while the LV sphericity index decreased (P < 0.001) immediately after pericardial incision. The GLS, GCS, and twist significantly decreased, while the GRS notably increased (P < 0.001). The LV volumes and LVEF remained unchanged.

Conclusions

Pericardial incision immediately transformed LV morphology from an ellipsoid to sphere, with decreased longitudinal and circumferential strain and twist, and increased radial strain, while LVEF remained unchanged. This should be considered when evaluating LV systolic function in patients after CABG.

Effectiveness and outcomes of 2 therapeutic interventions for cardiac tamponade: A retrospective observational study

Pericardial effusions can either be drained by percutaneous pericardiocentesis (PCC) or by surgical pericardiotomy (SP), with limited evidence of superiority for the management of cardiac tamponade (CTa).This study uses the US Nationwide Emergency Department Sample database to investigate the effectiveness of SP and PCC in patients with CTa in terms of clinical outcomes and healthcare costs.Retrospective observational study conducted on the US Nationwide Emergency Department Sample 2014 dataset CTa patients. Descriptive and multivariate logistic regression analyses were done to assess the impact of different procedures (none, SP, PCC, SP, and PCC) on mortality.A total of 10,410 CTa patients were included, of which 28.9% underwent no procedure, 32.9% underwent SP, 30.2% underwent PCC and 8.0% underwent SP and PCC. Mortality rates were highest in patients undergoing no procedure (22.3%) followed by PCC (15.0%), SP and PCC (11.5%), and then SP (9.6%) (P < .001). SP patients had longer length of stay (11.65 vs 8.16 days, P < .001) and higher total charges ($162,889.1 vs $100,802, P < .001) compared to PCC patients. Undergoing any procedure for CTa reduced the rate of mortality compared to no procedure with SP being the most effective (OR = 0.323, 95%CI 0.244-0.429), followed by SP & PCC (OR = 0.387, 95% CI 0.239-0.626), and then PCC (OR = 0.582, 95% CI 0.446-0.760).Adult CTa patients treated with SP had lower mortality rates but longer length of stay and higher healthcare expenses. This SP associated benefit remained consistent across different subpopulations after stratifying by age and potential disease etiology.

Long-Term Outcome of Pericardial Drainage in Cases of Chronic, Large, Hemodynamically Insignificant, C-Reactive Protein Negative, Idiopathic Pericardial Effusions

Pericardial effusion (PE) prognosis depends on the underlying etiology. We sought to assess the outcome of patients with chronic (>3 months), large (diastolic echo-free space >2 cm), idiopathic (without apparent etiology), C-reactive protein (CRP) negative PE, a topic where data are lacking. A total of n = 74 patients were enrolled in this study. Patients were treated by pericardiocentesis (n = 39) or surgical pericardial "window" (PW) (n = 13) or conservatively (n = 22). The median follow-up was 24 months (interquartile range: 15 to 38). Among those patients who had PE drained (n = 52), PE re-accumulation occurred in 32 cases (61.5%) and the rate was significantly higher in the pericardiocentesis subgroup (76.9% for pericardiocentesis vs 15.4% for PW group, p <0.001). Patients with re-accumulation had longer disease duration (32.1 ± 25.7 months vs 19.5 ± 23.8 months, p = 0.01), higher maximum PE diameter (32.2 ± 9.4 mm vs 26.1 ± 4.9 mm, p = 0.003) and larger PE volume drained at baseline (1,912 ± 707 mL vs 1,508 ± 387 mL, p = 0.04). Large PE re-accumulation occurred in 41% of patients who underwent pericardiocentesis and in 7.7% of those who underwent PW. In Cox survival analysis the only independent predictor of fluid re-accumulation was the type of intervention, with PW being associated with significantly reduced risk (hazard ratio 0.115, 95% confidence interval 0.015 to 0.875, p = 0.037). Major complications needing treatment were recorded in 12.8% and 15.4% (p = 0.999) of patients who underwent pericardiocentesis and PW, respectively. Moreover, invasive procedures were not helpful in establishing new diagnoses and guide treatment. In conclusion, in asymptomatic patients with chronic, large, hemodynamically insignificant, CRP negative, idiopathic PE, conservative management seems a more reasonable approach in most cases.

Hemopericardio por disparo sin lesión cardíaca, descripción de un mecanismo de trauma

Introducción. Durante muchos siglos, las heridas del corazón se consideraron fatales. Actualmente, el trauma cardíaco sigue siendo una de las lesiones más letales. Los resultados de pacientes con lesión cardíaca penetrante pueden variar de lesiones letales a arritmias que se resuelven espontáneamente. El hemopericardio en el trauma generalmente es debido a la lesión cardíaca penetrante, pero el saco pericárdico puede llenarse de sangre de grandes vasos y de la ruptura de la arteria pericardiofrénica asociada a laceración pericárdica contusa. Métodos. Para la organización de este estudio, se realizó una búsqueda bibliográfica en la literatura científica. Dos casos fueron observados por el equipo de Cirugía General al describir este raro mecanismo de trauma. Resultados. Descripción de una causa diferente de hemopericardio, ocasionada por la sangre de la cavidad peritoneal. Discusión. En los casos presentados, la lesión por arma de fuego rompió la barrera entre las cavidades pericárdica y peritoneal (diafragma), colocando cavidades con diferentes niveles de presión, favoreciendo la entrada de sangre de la cavidad peritoneal al saco pericárdico. Conclusión. En los casos observados el proyectil pasó muy cerca del corazón, pero sin lesionarlo. La ruptura de la superficie diafragmática del pericardio permitió que la presión de la cavidad peritoneal se igualara con la presión del pericardio.

Hypothyroidism Causing Pericardial Effusion: A Case Report

Hypothyroidism is an endocrine disorder with worldwide prevalence that can affect multiple organ systems. It can be asymptomatic and subclinical or overtly symptomatic with a potential to get complicated by fatal pathologies. It is an established cause of pericardial effusion, which in turn can be complicated by cardiac tamponade and severe hemodynamic instability. Herein we report the case of a 68-year-old male with history of Graves' disease treated with radioiodine ablation and consequent hypothyroidism, presenting with moderate pericardial effusion.

Technologies for intrapericardial delivery of therapeutics and cells

The pericardium, which surrounds the heart, provides a unique enclosed volume and a site for the delivery of agents to the heart and coronary arteries. While strategies for targeting the delivery of therapeutics to the heart are lacking, various technologies and nanodelivery approaches are emerging as promising methods for site specific delivery to increase therapeutic myocardial retention, efficacy, and bioactivity, while decreasing undesired systemic effects. Here, we provide a literature review of various approaches for intrapericardial delivery of agents. Emphasis is given to sustained delivery approaches (pumps and catheters) and localized release (patches, drug eluting stents, and support devices and meshes). Further, minimally invasive access techniques, pericardial access devices, pericardial washout and fluid analysis, as well as therapeutic and cell delivery vehicles are presented. Finally, several promising new therapeutic targets to treat heart diseases are highlighted.

Diagnostic Roles of Postmortem cTn I and cTn T in Cardiac Death with Special Regard to Myocardial Infarction: A Systematic Literature Review and Meta-Analysis

Background: Cardiac troponin I (cTn I) and cardiac troponin T (cTn T) are currently widely used as diagnostic biomarkers for myocardial injury caused by ischemic heart diseases in clinical and forensic medicine. However, no previous meta-analysis has summarized the diagnostic roles of postmortem cTn I and cTn T. The aim of the present study was to meta-analyze the diagnostic roles of postmortem cTn I and cTn T for cardiac death in forensic medicine, present a systematic review of the previous literature, and determine the postmortem cut-off values of cTn I and cTn T. Methods: We searched multiple databases for the related literature, performed a meta-analysis to investigate the diagnostic roles of postmortem cardiac troponins, and analyzed the receiver operating characteristic (ROC) curve to determine their postmortem cut-off values. Results and Conclusions: The present meta-analysis demonstrated that postmortem cTn I and cTn T levels were increased in pericardial fluid and serum in cardiac death, especially in patients with acute myocardial infarction (AMI). We determined the postmortem cut-off value of cTn I in the pericardial fluid at 86.2 ng/mL, cTn I in serum at 9.5 ng/mL, and cTn T in serum at 8.025 ng/mL.

Comparison between optical microscopy and automation for cytometric analysis of pericardial fluids in a cohort of adult subjects undergoing cardiac surgery

Aims

Limited information is available on number and type of cells present in the pericardial fluid (PF). Current evidence and has been garnered with inaccurate application of guidelines for analysis of body fluids. This study was aimed at investigating the performance of automate cytometric analysis of PF in adult subjects.

Methods

Seventy-four consecutive PF samples were analysed with Sysmex XN with a module for body fluid analysis (XN-BF) and optical microscopy (OM). The study also encompassed the assessment of limit of blank, limit of detection and limit of quantitation (LoQ), imprecision, carryover and linearity of XN-BF module.

Results

XN-BF parameters were compared with OM for the following cell classes: total cells (TC), leucocytes (white blood cell [WBC]), polymorphonuclear (PMN) and mononuclear (MN) cells. The relative bias were −4.5%, 71.2%, 108.2% and −47.7%, respectively. Passing and Bablok regression yielded slope comprised between 0.06 for MN and 5.8 for PMN, and intercept between 0.7 for PMN and 220.3 for MN. LoQ was comprised between 3.8×106 and 6.0×106 cells/L for WBC and PMN. Linearity was acceptable and carryover negligible.

Conclusions

PF has a specific cellular composition. Overall, automated cell counting can only be suggested for total number of cells, whereas OM seems still the most reliable option for cell differentiation.

BNP and NT-proBNP as Diagnostic Biomarkers for Cardiac Dysfunction in Both Clinical and Forensic Medicine

Currently, brain natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) are widely used as diagnostic biomarkers for heart failure (HF) and cardiac dysfunction in clinical medicine. They are also used as postmortem biomarkers reflecting cardiac function of the deceased before death in forensic medicine. Several previous studies have reviewed BNP and NT-proBNP in clinical medicine, however, few articles have reviewed their application in forensic medicine. The present article reviews the biological features, the research and application status, and the future research prospects of BNP and NT-proBNP in both clinical medicine and forensic medicine, thereby providing valuable assistance for clinicians and forensic pathologists.

Pericardial diseases in patients with hypothyroidism

Hypothyroidism is a well-known cause of pericardial effusion (with an incidence of 3%-37%) and can cause cardiac tamponade in severe cases. In this review, we present the current knowledge on the epidemiology of hypothyroid-induced pericardial diseases, the mechanism through which low thyroid hormone levels affect the pericardium, the associated clinical manifestations, diagnostic tests and management options. Hypothyroidism causes pericardial effusion through increased permeability of the epicardial vessels and decreased lymphatic drainage of albumin, resulting in accumulation of fluid in the pericardial space. Interestingly, autoimmunity does not seem to play a major role in the pathophysiology, and a majority of effusions are asymptomatic due to slow fluid accumulation. The diagnosis is generally made when the pericardial disease is associated with an elevated thyroid-stimulating hormone level, and other secondary causes are excluded. Management consists of thyroid replacement therapy, along with pericardial drainage in case of tamponade.In conclusion, hypothyroidism-induced pericardial diseases are underdiagnosed. Initiating treatment early in the disease process and preventing complications relies on early diagnosis through systematic screening per guidelines.

Biochemical investigations performed in pericardial fluid in forensic cases that underwent postmortem angiography

Postmortem biochemical investigations in vitreous humor samples collected before and after performing multiphase postmortem computed tomography angiography were performed in the past and demonstrated that specific contrast material injection allowed perfusion and radiological identification of the main vessels of the eye to be obtained without any changes in vitreous humor composition. In the study presented herein, we aimed to test whether the injection of the same contrast material using the same postmortem angiography protocol might influence pericardial fluid composition. Postmortem biochemical investigations were performed on pericardial fluid samples collected from bodies that underwent postmortem angiography (n = 16) prior to and post angiography. Two pericardial fluid samples were analyzed. No statistically significant differences were noticed among levels of any tested markers (urea nitrogen, creatinine, uric acid, C-reactive protein, procalcitonin, beta-hydroxybutyrate, and total IgE levels) in pericardial fluid samples collected prior to and post angiography, leading to the conclusion that pericardial fluid sampling can be delayed until after postmortem angiography when a specific contrast material injection is used.