Predictors of protein losing enteropathy after Fontan completion: An 8-year retrospective study at Sheikh Khalifa Medical City.

BACKGROUND: The Fontan procedure is the final stage of a three-stage palliation process in patients born with a univentricular heart as part of hypoplastic left heart syndrome (HLHS) or other pathologies with a univentricular heart. As essential as this procedure has proven to be for such cases, the Fontan physiology diminishes cardiac output and expands systemic venous pressure, which then leads to venous congestion that can be complicated by protein-losing enteropathy (PLE). This retrospective study aimed to identify the predictors of such complications in all patients who underwent completion of the Fontan procedure at our center (Sheikh Khalifa Medical City/SKMC) in the past eight years. METHODS: This study examined the medical records of patients who underwent completion of Fontan repair at our center since the inauguration of the cardiac surgery program of SKMC in the United Arab Emirates (UAE) - 01 Jan 2012 to 31 Dec 2020. Exclusion criteria included the absence of any of the undermentioned data in patient files. Patients were divided into two groups: those who developed PLE and those who did not. For each group, the following data were collected: demographics data (current age and age at completion of Fontan), clinical and laboratory data (oxygen saturation, serum albumin), echocardiographic data (classification of original cardiac diagnosis, degree of atrio-ventricular valve regurgitation, ventricular functions), hemodynamic data (mean pressures of superior vena cava and pulmonary arteries before Fontan completion), operative data (type of initial palliation, type of Fontan, presence of fenestrations and its size) and the need for any cardiac intervention prior to Fontan completion, such as atrio-ventricular valve repair, peripheral pulmonary stenting and arch balloon dilatation. RESULTS: Of the 48 included patients,13 (25%) developed PLE. Multivariate regression analysis proved that the best predictors of PLE were superior vena cava mean pressure (P = 0.012) and the degree of atrio-ventricular valve regurgitation (P = 0.013). An oxygen saturation <83% prior to Fontan completion was 92% sensitive in predicting PLE after Fontan completion. CONCLUSION: This is a single-center study of the predictors of PLE after Fontan procedure and, as expected from similar studies, SVC pressure higher than 11 mmHg and moderate-to-severe atrio-ventricular valve regurgitation were predictors of Fontan failure. The higher prevalence of PLE in our cohort, as well as lower cut-offs of SVC pressure that can predict complications, may be related to the predominance of hypoplastic left heart in the operated patients, which has been the main referral center for cardiac surgeries in UAE in the last decade.

Advanced Echocardiography Techniques: The Future Stethoscope of Systemic Diseases.

Cardiovascular disease (CVD) has been showing patterns of extensive rise in prevalence in the contemporary era, affecting the quality of life of millions of people and leading the causes of death worldwide. It has been a provocative challenge for modern medicine to diagnose CVD in its crib, owing to its etiological factors being attributed to a large array of systemic diseases, as well as its non-binary hideous nature that gradually leads to functional disability. Novel echocardiography techniques have enabled the cardiac ultrasound to provide a comprehensive analysis of the heart in an objective, feasible, time- and cost-effective manner. Speckle tracking echocardiography, contrast echocardiography, and 3D echocardiography have shown the highest potential for widespread use. The uses of novel modalities have been elaborately demonstrated in this study as a proof of concept that echocardiography has a place in routine general practice with supportive evidence being as recent as its role in the concurrent COVID-19 pandemic. Despite such evidence, many uses remain off-label and unexploited in practice. Generalization of echocardiography at the point of care can become a much-needed turning point in the clinical approach to case management. To actualize such aspirations, we recommend further prospective and interventional studies to examine the effect of implementing advanced techniques at the point of care on the decision-making process and evaluate their effectiveness in prevention of cardiovascular morbidities and mortalities.

JAK out of the Box; The Rationale behind Janus Kinase Inhibitors in the COVID-19 setting, and their potential in obese and diabetic populations.

The adaptive use of Janus kinase (JAK)-inhibitors has been suggested by rheumatology experts in the management of COVID-19. We recount the rationale behind their use in this setting, and the current evidence for and against their use in this review. JAK-inhibitors role in COVID-19 infection appears to be multifaceted, including preventing viral endocytosis and dampening the effect of excessive chemokines. This drug class may be able to achieve these effects at already preapproved dosages. Concerns arise regarding reactivation of latent viral infections and the feasibility of their use in those with severe disease. Most interestingly, JAK-Inhibitors may also have an additional advantage for diabetic and obese populations, where the dysregulation of JAK-signal transducer and activator of transcription pathway may be responsible for their increased risk of poor outcomes. Targeting this pathway may provide a therapeutic advantage for these patient groups.

PPAR agonists as effective adjuvants for COVID-19 vaccines, by modifying immunogenetics: a review of literature.

BACKGROUND: Several coronavirus vaccine have been fast-tracked to halt the pandemic, the usage of immune adjuvants that can boost immunological memory has come up to the surface. This is particularly of importance in view of the rates of failure of seroconversion and re-infection after COVID-19 infection, which could make the vaccine role and response debatable. Peroxisome proliferator-activated receptors (PPARs) have an established immune-modulatory role, but their effects as adjuvants to vaccination have not been explored to date. It is increasingly recognized that PPAR agonists can upregulate the levels of anti-apoptotic factors such as MCL-1. Such effect can improve the results of vaccination by enhancing the longevity of long-lived plasma cells (LLPCs). The interaction between PPAR agonists and the immune system does not halt here, as T cell memory is also stimulated through enhanced T regulatory cells, antagonizing PD-L1 and switching the metabolism of T cells to fatty acid oxidation, which has a remarkable effect on the persistence of T memory cells. What is even of a more significant value is the effect of PPAR gamma on ensuring a profound secretion of antibodies upon re-exposure to the offending antigen through upregulating lipoxin B4, therefore potentially assisting the vaccine response and deterring re-infection. SHORT CONCLUSION: In view of the above, we suggest the use of PPAR as adjuvants to vaccines in general especially the emerging COVID-19 vaccine due to their role in enhancing immunologic memory through DNA-dependent mechanisms.

The potential use of lactate blockers for the prevention of COVID-19 worst outcome, insights from exercise immunology.

Following the decline in Physical Activity (PA) due to COVID-19 restrictions in the form of government mandated lockdowns and closures of public spaces, the modulatory effect of physical exercise on immunity is being heavily revisited. In an attempt to comprehend the wide discrepancy in patient response to COVID-19 and the factors that potentially modulate it, we summarize the findings relating PA to inflammation and immunity. A distinction is drawn between moderate intensity and high intensity physical exercise based on the high lactate production observed in the latter. We hypothesize that, the lactate production associated with high intensity anaerobic exercise is implicated in the modulation of several components of the innate and adaptive immunity. In this review, we also summarize these immunomodulatory effects of lactate. These include increasing serum IL-6 levels, the main mediator of cytokine storms, as well as affecting NK cells, Macrophages, Dendritic cells and cytotoxic T-lymphocytes. The implications of high lactate levels in athletic performance are highlighted where athletes should undergo endurance training to increase VO2 max and minimize lactate production. Tumor models of hypoxia were also reported where lactate levels are elevated leading to increased invasiveness and angiogenesis. Accordingly, the novel lactate blocking strategy employed in cancer treatment is evaluated for its potential benefit in COVID-19 in addition to the readily available beta-blockers as an antagonist to lactate. Finally, we suggest the diagnostic/prognostic purpose of the elevated lactate levels that can be determined through sweat lactate testing. It is the detrimental effect of lactate on immunity and its presence in sweat that qualify it to be used as a potential non-invasive marker of poor COVID-19 outcome.

The overlooked left ventricle in persistent pulmonary hypertension of the newborn.

Introduction: Persistent pulmonary hypertension of the newborn (PPHN) is a rapidly increasing condition among neonates. It represents failure of adaptation of pulmonary circulation to the extrauterine environment causing severe hypoxemia in affected newborns. Few data have weighed the relationship of ventricular dysfunction in the context of PPHN and the outcome in involved patients. The aim of this paper is to study ventricular functions in newborns with PPHN and to determine whether short-term outcome is closely related or not to ventricular dysfunction occurring in PPHN.Methods: Thirty full-term neonates with PPHN were screened with conventional echocardiography and tissue Doppler imaging (TDI) for the assessment of ventricular functions at the start of treatment for PPHN, demographic data and Arterial blood gazes were performed as well. The echocardiographic data were compared to healthy age-matched controls. The sensitivity and specificity of relevant echocardiographic data to predict the short-term (Day 3) outcome of patients were measured.Results: Patients with PPHN had both left ventricular (LV) and right ventricular (RV) dysfunction when compared to controls, RV Tei (Cases: 0.39 ± 0.1 versus controls: 0.29 ± 0.08, p < .01) LV Tei (Cases: 0.3 ± 0.04 versus controls: 0.25 ± 0.02, p < .01), LV functions were found of greatest prediction of negative outcome in cases with PPHN than RV Tei.Conclusion: The aforementioned findings are sight opening towards the importance of LV dysfunction in PPHN, LV dysfunction might occur in PPHN as a result of RV-LV interactions and the observed involvement might be an important aggravating factor of PPHN.

Peroxisome proliferator-activated receptor agonists and reversal of vascular degeneration through DNA repair, a step toward drug-induced regenerative medicine.

Endothelial dysfunction with subsequent degeneration and vasoocclusive remodeling is the hallmark of many cardiovascular disorders including pulmonary vascular disease (PVD). To date, the available treatments slows disease progression but does not prevent deterioration. Reversing such pathologies would spare many patients risky surgeries and long waiting lists for a possible organ donor. Peroxisome proliferator-activated receptor agonists were first introduced as sole insulin sensitizers, however, there is increasing body of evidence that they have different actions on DNA which might help reverse vascular degeneration. This effect appears to be mainly achieved through enhancement of DNA damage responses (DDR). The aforementioned effect could offer new insights about repurposing drugs for achieving organ or tissue regeneration, an understudied field named drug-induced regenerative medicine.

Revisiting the pathogenic role of insulin resistance in Duchenne muscular dystrophy cardiomyopathy subphenotypes.

INTRODUCTION: Duchenne muscular dystrophy (DMD) is known to impact the subepicardial layer of the myocardium through chronic inflammation. Recent animal studies have shown predominant subendocardial involvement in rats with DMD. The primary outcome parameter was to determine by cardiovascular MRI (CMR) if two differential patterns of myocardial involvements exist in DMD; the secondary outcome parameters were to correlate the observed pattern with metabolic markers such as insulin resistance measures. METHODS: Forty patients with DMD were screened using CMR to determine which of them had predominantly subendocardial dysfunction (SENDO group), or subepicardial/midmyocardial involvement (SEPMI group). Patients were subjected to body mass index measurement, serum creatinine kinase, serum lactate dehydrogenase enzyme, fasting glucose-insulin ratio (FGIR), full lipid profile, left ventricular ejection fraction (LVEF), left ventricle E/E´ ratio (the ratio of early mitral inflow velocity to average early diastolic velocities of the basal septum and mitral annulus) for left ventricle diastolic function, and myocardial layer strain discriminating echocardiography (MLSD-STE). Results: 26 patients displayed SENDO while 34 displayed SEPMI. SENDO group displayed overt insulin resistance; (FGIR (SENDO: 7 ± 1 vs. SEPMI: 5 ± 1, P < 0.001). FGIR was negatively correlated with Subendocardial Global Longitudinal Strain (ENDO-LS) with r = -0.75. CONCLUSION: DMD does not seem to influence the heart uniformly; DMD cardiomyopathy probably has two separate phenotypes with different mechanisms. Insulin resistance might be implicated in its pathogenesis and its reversal may help to slow disease progression.

Right ventricular functions in subphenotypes of sickle cell disease.

OBJECTIVES: Sickle cardiomyopathy is the most important cause of death in patients with sickle cell disease (SCD). Based on recent evidence, SCD can be divided into two subphenotypes, namely, the viscosity vasoocclusion (VVO) subphenotype and the hemolysis endothelial dysfunction (HED) subphenotype. The aim of our series is to study right ventricular (RV) functions in both subphenotypes. METHODS: Echocardiography including conventional and tissue Doppler imaging as well as speckle tracking echocardiography was performed in 50 patients (23 from the VVO subgroup and 27 from the HED subgroup) based on a serum lactate dehydrogenase (LDH) level below or above 270 U/L, respectively, and in 50 controls. Reticulocyte count and hemoglobin levels were assessed in different groups of patients. RESULTS: The HED subgroup showed RV dysfunction. Patients in this subgroup also showed systolic and diastolic functions similar to those seen in the VVO subgroup and controls. In addition, a tight correlation exists between LDH and both RV global longitudinal strain (-0.68) and RV E/E' ratio (0.9), defined as the ratio of early diastolic tricuspid inflow velocity to tricuspid annular early diastolic velocity. CONCLUSIONS: Results reveal a marked discrepancy in RV functions between HED and VVO subphenotypes of SCD, with patients in the former subgroup being more prone to RV dysfunction. This warrants early screening of such patients in daily practice.

The potential use of ABO blood group system for risk stratification of COVID-19.

ABO blood groups is a cheap and affordable test that can be immediately retrieved from COVID-19 patients at the diagnosis. There is increasing evidence that non-O blood groups have both higher susceptibility and higher severity of COVID-19 infections. The reason behind such relationship seems elusive. Regarding susceptibility, Non-O individuals have Anti-A antibodies which can prevent viral entry across ACE-2 receptors, moreover, Non-O individuals are at higher risk of autoimmunity, hypercoagulable state, and dysbiosis resulting in an augmented tendency for vascular inflammatory sequelae of COVID-19. We can conclude, on the diagnostic level, that ABO blood groups can be potentially used for risk stratification of affected COVID-19 patients, to anticipate the deterioration of patients at higher risk for complications. On a therapeutic level, plasma from normal O blood group individuals might potentially replace the use of convalescent serum for the treatment of COVID-19.

Single cell sequencing unraveling genetic basis of severe COVID19 in obesity.

COVID-19 has shown a substantial variation in the rate and severity by which it impacts different demographic groups. Specifically, it has shown a predilection towards obese patients as well as well as other vulnerable groups including predilection of males over females, old age over young age and black races over Caucasian ones. Single cell sequencing studies have highlighted the role of cell polarity and the co-expression of proteases, such as Furin, along with ACE2 in the genesis of coronavirus disease rather than exclusively link tissue involvement with ACE2 levels thought previously. It has also forged a connection between the genetic and immune cellular mechanisms underlying COVID infection and the inflammatory state of obese patients, offering a more accurate explanation as to why obese patients are at increased risk of poor COVID outcomes. These commonalities encompass macrophage phenotype switching, genetic expression switching, and overexpression of the pro-inflammatory cytokines, depletion of the regulatory cytokines, in situ T cell proliferation, and T cell exhaustion. These findings demonstrate the necessity of single cell sequencing as a rapid means to identify and treat those who are most likely to need hospital admission and intensive care, in the hopes of precision medicine. Furthermore, this study underlines the use of immune modulators such as Leptin sensitizers, rather than immune suppressors as anti-inflammation therapies to switch the inflammatory response from a drastic immunological type 1 response to a beneficial type 2 effective one.

Is it infection or rather vascular inflammation? Game-changer insights and recommendations from patterns of multi-organ involvement and affected subgroups in COVID-19.

Coronavirus disease 2019 (COVID-19) is a serious illness that has rapidly spread throughout the globe. The seriousness of complications puts significant pressures on hospital resources, especially the availability of ICU and ventilators. Current evidence suggests that COVID-19 pathogenesis majorly involves microvascular injury induced by hypercytokinemia, namely interleukin 6 (IL-6). We recount the suggested inflammatory pathway for COVID-19 and its effects on various organ systems, including respiratory, cardiac, hematologic, reproductive, and nervous organ systems, as well examine the role of hypercytokinemia in the at-risk geriatric and obesity subgroups with upregulated cytokines' profile. In view of these findings, we strongly encourage the conduction of prospective studies to determine the baseline levels of IL-6 in infected patients, which can predict a negative outcome in COVID-19 cases, with subsequent early administration of IL-6 inhibitors, to decrease the need for ICU admission and the pressure on healthcare systems. Video abstract: http://links.lww.com/CAEN/A24.

Possible molecular and paracrine involvement underlying the pathogenesis of COVID-19 cardiovascular complications.

Coronavirus disease 2019 (COVID-19) has been declared a pandemic on 11 March 2020 by the WHO. Despite being mainly a respiratory virus, cardiac complications have been described. These range from sudden cardiac death to subtle diastolic dysfunction after recovery from COVID-19. The commonest cardiac presentation to date is acute heart failure resulting from biventricular or left ventricular hypokinesis and elevation of cardiac troponins. It has been shown that COVID-19 downregulates angiotensin-converting enzyme-2, which has protective effects on the endothelium and cardiomyocytes. It has also been proven that COVID-19 induces a state of hypercytokinaemia, some cytokines such as interleukin-1 and interleukin-6 have an injurious effect on the myocardium and endothelium, respectively. Such pathogenic mechanisms might play a crucial role in induction of cardiomyocyte injury and impaired myocardial perfusion probably through coronary endothelial dysfunction. The understanding and linking of such mechanisms might help in tailoring drug repurposing for treatment or prophylaxis of COVID-19 cardiovascular complications.

A multicenter consensus: A role of furin in the endothelial tropism in obese patients with COVID-19 infection.

Furin, a cleavage enzyme, is increasingly recognized in the pathogenesis of metabolic syndrome. Its cleavage action is an essential activation step for the endothelial pathogenicity of several viruses including SARS-CoV-2. This Furin-mediated endothelial tropism seems to underlie the multi-organ system involvement of COVID-19; which is a feature that was not recognized in the older versions of coronaviridae. Obese and diabetic patients, males, and the elderly, have increased serum levels of Furin, with its increased cellular activity; this might explain why these subgroups are at an increased risk of COVID-19 related complications and deaths. In contrast, smoking decreases cellular levels of Furin, this finding may be at the origin of the decreased severity of COVID-19 in smokers. Chinese herbal derived luteolin is suggested to be putative Furin inhibitor, with previous success against Dengue Fever. Additionally, Furin intracellular levels are largely dependent on concentration of intracellular ions, notably sodium, potassium, and magnesium. Consequently, the use of ion channel inhibitors, such as Calcium Channel blockers or Potassium Channel blockers, can prevent cellular transfection early in the course of the illness. Nicotine patches and Colchicine have also been suggested as potential therapies due to Furin mediated inhibition of COVID-19.

Biventricular reverse remodeling and relationship with mitral valve prolapse after transcatheter closure of ASD secundum, a 3D echocardiographic study.

Introduction: Mitral valve prolapse (MVP) is the most common anomaly of the mitral valve. Several studies have shown prevalence of MVP in atrial septal defect (ASD) especially secundum types (II). The aims of this study is to show the potential role of 3D echocardiography in improving the diagnosis of MVP and to depict the relationship between reverse remodeling of the right and left ventricles (RV, LV) and MVP after transcatheter closure of ASD II. Methods: Sixty patients underwent transcatheter closure of ASD II and completed follow up by 2D and 3D echocardiography in Cairo University Children Hospital before the procedure and at 24 hours, 1 and 6 months after the procedure. Results: 3D echocardiography was more accurate than 2D echocardiography in detecting MVP frequency in ASD II patients (75% vs. 50%). Maximum statistically significant remodeling was detected by 3D echocardiography 1 month after the procedure (RV: LV ratio by 3D echocardiography 1.9±0.03 24 hours after the procedure vs. 1.6±0.03 1 months after the procedure, P <0.01) while 2D echocardiography was delayed in detecting biventricular reverse remodeling. 3D derived RV: LV ratio was accurate in detecting MVP status with a sensitivity of 88%. Conclusion: MVP in ASD II may be related to Biventricular remodeling; 3D echocardiography is accurate in the detection of reverse remodeling as well as MVP in ASD II patients before and after device closure.

Discrepancy in patterns of myocardial involvement in beta-thalassaemia vs. sickle cell anaemia.

Introduction: Different mechanisms contribute to myocardial dysfunction in sickle cell disease [SCD] and beta thalassaemia major [TM]. TM mainly involves the highly vascular subepicardium by iron load and SCD mainly operates by inducing ischaemia in the relatively ischaemic subendocardium. The aim of this article was to determine if pattern of left ventricular [LV] dysfunction differ among the two groups of patients.Methods: Forty TM and 40 SCD patients and 40 age- and surface area-matched controls were subjected to conventional echocardiography, 2D Speckle tracking myocardial layer strain discriminating echocardiography (MLSD-STE) which is able to discriminate if myocardial dysfunction is predominantly subepicardial or subendocardial and 3D echocardiography for ejection fraction assessment as well as haemoglobin, ferritin, and lactate dehydrogenase levels.Results: TM patients had a deeper subepicardial dysfunction while SCD had prevalent subendocardial dysfunction, epicardial GLS (TM: -10.9 ± 2 vs. SCD: 19.9 ± 1.7; p value < 0.01); endocardial GLS (TM: -19.9 ± 1.7 vs. SCD: -10.6 ± 1.6, p value < 0.01).Conclusion: This study points towards divergent microcirculatory mechanisms in the pathogenesis of myocardial dysfunction in haemoglobinopathies. It shows predominant subendocardial dysfunction with underlying ischaemia of SCD and prevalent subepicardial iron-induced injury in cases of TM.

Low iron mitigates viral survival: insights from evolution, genetics, and pandemics-a review of current hypothesis.

Background: Upon re-examination of our human history, evolutionary perspectives, and genetics, a prevailing iron deficiency phenotype appears to have evolved to protect the human race from extinction. Body: In this review, we summarize the evolutionary and genetic perspectives pointing towards the hypothesis that low iron mitigates infection. The presence of infection promotes the generation of resistance alleles, and there are some evolutionary and genetic clues that suggest the presence of an iron deficiency phenotype that may have developed to protect against infection. Examples include the relative paucity of iron overload genes given the essential role of iron, as well as the persistence of iron deficiency among populations in spite of public health efforts to treat it. Additional examination of geographic areas with severe iron deficiency in the setting of pandemics including H1N1, SARS, and COVID-19 reveals that areas with higher prevalence of iron deficiency are less affected. RNA viruses have several evolutionary adaptations which suggest their absolute need for iron, and this dependency may be exploited during treatment. Conclusion: RNA viruses pose a unique challenge to modern healthcare, with an average of 2-3 new pathogens being discovered yearly. Their overarching requirements for iron, along with human evolutionary and genetic adaptations which favored an iron deficiency phenotype, ultimately suggest the potential need for iron control in these infections.

Development of tissue Doppler-derived predictors of hemodynamically significant patent ductus arteriosus and the ability to incorporate it in targeted neonatal echocardiography protocol.

BACKGROUND: Hemodynamically significant (HS) patent ductus arteriosus (PDA) is a significant cause of mortality in preterm neonates. Early detection of HS PDA and pre-symptomatic closure may help in avoiding complications. For this to happen, easily performed predictors must be available; the aim of this paper is to test the reliability and repeatability of tissue Doppler-derived parameters for prediction of HS PDA. METHODS: Preterm neonates <32 weeks were screened with echocardiography at Day 3 of life; 80 neonates with PDA were classified into HS group and hemodynamically insignificant (HIS) group based on benchmark parameter namely left ventricular outflow to superior vena caval flow ratio (LVO/SVC), and a ratio ≥4 was considered predictive of HS PDA. Tissue Doppler-derived left ventricular myocardial systolic and diastolic velocities were also performed. RESULTS: In total, 105 neonates (55 among HS and 60 among HIS groups) were included in the study. Septal systolic velocity (S') proved of high sensitivity (100%) in the prediction of HS PDA; nevertheless, it proved to be more repeatable than the initially discriminating parameter (LVO/SVC) with a Kappa of 0.92. CONCLUSION: This study concludes that septal S' can be reliably used even by neonatologists for pre-symptomatic detection of HS PDA. This may also indicate the need of adding tissue Doppler parameters to the standard protocol of targeted neonatal echocardiography.