Coronary microvascular dysfunction pathophysiology in COVID-19

Assessment of myocardial injury by SPECT myocardial perfusion imaging in patients with COVID-19 infection in a single center after lifting the restrictions in China

PURPOSE

To assess myocardial injury using rest single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in patients with COVID-19 and to evaluate whether myocardial injury detected by rest MPI predict the prognosis of symptoms after 6 months follow-up.

METHODS

Patients suspected of myocarditis between December 2022 and March 2023, after the lifting of COVID-19 pandemic restrictions, and between December 2018 and March 2019, prior to the pandemic, were referred to our study. All patients underwent rest MPI. One hundred and sixty four patients with COVID-19 infection after the lifting of pandemic restrictions and 101 patients before the pandemic were included as the study and control groups, respectively. One hundred and fifty three patients of the study group and 83 of the control group presented symptoms when they initially visit to our department. Compare the parameters of myocardial injury detected by rest SPECT MPI between the two groups and then investigate the association between myocardial injury and symptom prognosis in symptomatic patients of both groups.

RESULTS

Total perfusion defect (TPD) (4.2% ± 3.3% vs. 2.3% ± 2.2%, P < 0.001), summed rest score (SRS) (5.3 ± 5.4 vs. 2.7 ± 2.0, P < 0.001), the proportion of patients with TPD > 4% (43.3% vs. 17.8%, P < 0.001), TPD > 10% (6.71% vs 0, P < 0.001), SRS > 4 (40.2% vs 15.8%, P < 0.001), SRS > 10 (12.8% vs 0, P < 0.001), the number of abnormal perfusion segments (3.9 ± 3.1 vs. 2.4 ± 1.7, P < 0.001) were all significantly higher in the study group. All the parameters of rest MPI were not associated with the prognosis of symptoms in symptomatic patients of both groups after 6 months follow-up.

CONCLUSION

Myocardial injury in COVID-19 patients could be assessed by rest SPECT MPI. The COVID-19 patients could exhibited a higher frequency and greater severity of myocardial injury than uninfected control patients. Myocardial injury assessed by rest MPI did not predict for the prognosis of symptoms in symptomatic patients of both COVID-19 patients and uninfected patients.

Coronary Implications of COVID-19

Patients with SARS-CoV-2 infection carry an increased risk of cardiovascular disease encompassing various implications, including acute myocardial injury or infarction, myocarditis, heart failure, and arrhythmias. A growing volume of evidence correlates SARS-CoV-2 infection with myocardial injury, exposing patients to higher mortality risk. SARS-CoV-2 attacks the coronary arterial bed with various mechanisms including thrombosis/rupture of preexisting atherosclerotic plaque, de novo coronary thrombosis, endotheliitis, microvascular dysfunction, vasculitis, vasospasm, and ectasia/aneurysm formation. The angiotensin-converting enzyme 2 receptor plays pivotal role on the cardiovascular homeostasis and the unfolding of COVID-19. The activation of immune system, mediated by proinflammatory cytokines along with the dysregulation of the coagulation system, can pose an insult on the coronary artery, which usually manifests as an acute coronary syndrome (ACS). Electrocardiogram, echocardiography, cardiac biomarkers, and coronary angiography are essential tools to set the diagnosis. Revascularization is the first-line treatment in all patients with ACS and obstructed coronary arteries, whereas in type 2 myocardial infarction treatment of hypoxia, anemia and systemic inflammation are indicated. In patients presenting with coronary vasospasm, nitrates and calcium channel blockers are preferred, while treatment of coronary ectasia/aneurysm mandates the use of antiplatelets/anticoagulants, corticosteroids, immunoglobulin, and biologic agents. It is crucial to untangle the exact mechanisms of coronary involvement in COVID-19 in order to ensure timely diagnosis and appropriate treatment. We have reviewed the current literature and provide a detailed overview of the pathophysiology and clinical spectrum associated with coronary implications of SARS-COV-2 infection.

The COVID-19 thrombus: distinguishing pathological, mechanistic, and phenotypic features and management

A heightened risk for thrombosis is a hallmark of COVID-19. Expansive clinical experience and medical literature have characterized small (micro) and large (macro) vessel involvement of the venous and arterial circulatory systems. Most events occur in patients with serious or critical illness in the hyperacute (first 1-2 weeks) or acute phases (2-4 weeks) of SARS-CoV-2 infection. However, thrombosis involving the venous, arterial, and microcirculatory systems has been reported in the subacute (4-8 weeks), convalescent (> 8-12 weeks) and chronic phases (> 12 weeks) among patients with mild-to-moderate illness. The purpose of the current focused review is to highlight the distinguishing clinical features, pathological components, and potential mechanisms of venous, arterial, and microvascular thrombosis in patients with COVID-19. The overarching objective is to better understand the proclivity for thrombosis, laying a solid foundation for screening and surveillance modalities, preventive strategies, and optimal patient management.

Soluble platelet selectin and platelets in COVID-19: a multifaceted connection

The COVID-19 pandemic has brought to light the intricate relationship between platelets, soluble platelet selectin (sP-selectin), and disease pathogenesis. Platelets, traditionally recognized for their role in hemostasis, have emerged as key contributors to the immunothrombotic complications observed in COVID-19 patients. Concurrently, elevated levels of sP-selectin, indicative of platelet activation and endothelial injury, have been consistently identified in COVID-19 patients and have shown associations with disease severity and adverse outcomes. This multifaceted connection underscores the pivotal role of platelets and sP-selectin in orchestrating thromboinflammation, vascular dysfunction, and disease progression in COVID-19. Platelet activation triggers the release of inflammatory mediators and promotes platelet-leukocyte interactions, amplifying the systemic inflammatory response and exacerbating endothelial injury. Additionally, platelet-derived factors contribute to microvascular thrombosis, further exacerbating tissue damage and organ dysfunction in severe COVID-19. Elevated sP-selectin levels serve as biomarkers for disease severity and prognostication, aiding in risk stratification and early identification of patients at higher risk of adverse outcomes. Therapeutic strategies targeting platelet dysfunction and sP-selectin-mediated pathways hold promise in mitigating thromboinflammation and improving outcomes in COVID-19 patients. Antiplatelet agents, platelet inhibitors, and anti-inflammatory therapies represent potential interventions to attenuate platelet activation, inhibit platelet-leukocyte interactions, and alleviate endothelial dysfunction. A comprehensive understanding of the multifaceted connection between platelets, sP-selectin, and COVID-19 pathogenesis offers opportunities for tailored therapeutic approaches aimed at mitigating thromboinflammation and improving patient outcomes in this complex and challenging clinical setting.

Coronary microvascular dysfunction in childhood: An emerging pathological entity and its clinical implications

Coronary microvascular dysfunction (CMD) encompasses a spectrum of structural and functional alterations in coronary microvasculature resulting in impaired coronary blood flow and consequent myocardial ischemia without obstruction in epicardial coronary artery. The pathogenesis of CMD is complex involving both functional and structural alteration in the coronary microcirculation. In adults, CMD is predominantly discussed in context with anginal chest pain or existing ischemic heart disease and its risk factors. The presence of CMD suggests increased risk of adverse cardiovascular events independent of coronary atherosclerosis. Coronary microvascular dysfunction is also known in children but is rarely recognized due to paucity of concommitent coronary artery disease. Thus, its clinical presentation, underlying mechanism of impaired microcirculation, and prognostic significance are poorly understood. In this review article, we will overview variable CMD reported in children and delineate its emerging clinical significance.

COVID-19 vaccines-associated Takotsubo cardiomyopathy: A narrative review

Takotsubo cardiomyopathy (TTC) is a severe, acute, reversible, and self-limited cardiac dysfunction. It usually affects postmenopausal women and is mostly triggered by physical or emotional stressors. Following the COVID-19 pandemic, millions of doses of different types of COVID-19 vaccines are being administered globally. There have been reports of different cardiac complications after receiving COVID-19 vaccines. To our knowledge, there have been 16 reported cases of COVID-19 vaccination-associated TTC. In this study, we first provide a brief overview of TTC and then an overview of selected reported TTC cases following COVID-19 vaccinations. It is crucial to highlight that the occurrence of TTC after vaccination does not establish a direct cause-and-effect relationship between immunization and TTC. Further investigations are necessary to examine any potential association between COVID-19 vaccines and the incidence of TTC. Additionally, the benefits of receiving COVID-19 vaccines significantly outweigh the potential risks of developing adverse events.

Association of the COVID-19 Pandemic on Treatment Times for ST-Elevation Myocardial Infarction: Observations from the Los Angeles County Regional System

Previous studies have documented longer treatment times and worse outcomes for patients with ST-elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PCI) during the COVID-19 pandemic. The objective of the present study was to evaluate the impact of the COVID-19 pandemic on treatment times and outcomes for patients with STEMI who underwent primary PCI within a regional system of care. This was a retrospective study using data from the Los Angeles County Emergency Medical Services Agency. Data on the emergency medical service activations were abstracted for patients with STEMI from March 19, 2020 to January 31, 2021, during the COVID-19 pandemic and for the same interval the previous year. All adult patients (≥18 years) with STEMI who underwent emergent coronary angiography were included. The primary end point was the first medical contact (FMC) to device time. The secondary end points included treatment time intervals, vascular complications, need for emergent coronary artery bypass surgery, length of hospital stay, and in-hospital mortality. During the study period, 3,017 patients underwent coronary angiography for STEMI, 1,893 patients pre-COVID-19 and 1,124 patients during COVID-19 (40% lower). A total of 2,334 patients (77%) underwent PCI. During the COVID-19 period, rates of PCI were significantly lower compared with the control period (75.1% vs 78.7%, p = 0.02). FMC to device time was shorter during the COVID-19 period compared with the control period (median 77.0 vs 81.0 minutes, p = 0.004). For patients with STEMI complicated by out-of-hospital cardiac arrest, FMC to device time was similar during the COVID-19 period compared with the control period (median 95.0 [33.0] vs 100.0 [40.0] minutes, p = 0.34). Vascular complications, the need for emergent bypass surgery, length of hospital stay, and in-hospital mortality were similar between the periods. In conclusion, in this large regional system of care, we found a relatively small but significant decrease in treatment times, yet overall, similar clinical outcomes for patients with STEMI who underwent primary PCI and were treated during the COVID-19 period compared with a control period. These findings suggest that mature cardiac systems of care were able to maintain efficient care despite the challenges of the COVID-19 pandemic.

Endothelial Senescence: From Macro- to Micro-Vasculature and Its Implications on Cardiovascular Health

Endothelial cells line at the most inner layer of blood vessels. They act to control hemostasis, arterial tone/reactivity, wound healing, tissue oxygen, and nutrient supply. With age, endothelial cells become senescent, characterized by reduced regeneration capacity, inflammation, and abnormal secretory profile. Endothelial senescence represents one of the earliest features of arterial ageing and contributes to many age-related diseases. Compared to those in arteries and veins, endothelial cells of the microcirculation exhibit a greater extent of heterogeneity. Microcirculatory endothelial senescence leads to a declined capillary density, reduced angiogenic potentials, decreased blood flow, impaired barrier properties, and hypoperfusion in a tissue or organ-dependent manner. The heterogeneous phenotypes of microvascular endothelial cells in a particular vascular bed and across different tissues remain largely unknown. Accordingly, the mechanisms underlying macro- and micro-vascular endothelial senescence vary in different pathophysiological conditions, thus offering specific target(s) for therapeutic development of senolytic drugs.

[Lung pathology in children with a long-term novel coronavirus infection COVID-19]

New coronavirus infection is registered less frequently in children than in adults. Among all patients with COVID-19, the share of children is 8.6%. Clinical practice shows that in children, COVID-19 can be severe and even fatal. Articles have been published reflecting the clinical manifestations of Long Covid in children, while data on pathomorphological examination of the lungs during long-term COVID-19 in children are not available in the literature. On the basis of the Department of Pathological Anatomy with a course of Forensic Medicine and the Pathological-Anatomical Department of the Clinic of St. Petersburg State Pediatric Medical University, an analysis of medical documentation was carried out, autopsy materials were selected from 3 observations of the death of children from COVID-19. The selection criterion was the duration of the disease. A histological examination using standard methods and IHC analysis using antibodies to the nucleocapsid of SARS-Cov-2, CD95, CD31 were carried out on the lung tissue of 3 children aged 2 months to 2 years who died from a new coronavirus infection. Microscopically, all three patients showed microvessels damage, their thrombosis, angiogenesis, as well as signs of diffuse alveolar damage The combination of expression of the SARS-CoV-2 nucleocapsid and the apoptosis marker on the vascular endothelium of the MCR is of interest.

CONCLUSION

The data obtained indicate infection with coronavirus and death of endothelial cells due to apoptosis. Endothelial damage in the microvessels of the lungs is the initiating factor in the development of capillary-alveolar block, tissue hypoxia, and disseminated intravascular coagulation syndrome, leading in some cases to respiratory/multiple organ failure and death.

Protective role of N-acetylcysteine and Sulodexide on endothelial cells exposed on patients' serum after SARS-CoV-2 infection

Severe acute respiratory syndrome coronavirus-2 causes hyperinflammation and activation of coagulation cascade and, as a result, aggravates endothelial cell dysfunction. N-acetylcysteine and Sulodexide have been found to mitigate endothelial damage. The influence on coronary artery endothelial cells of serum collected after 4 ± 1 months from coronavirus infection was studied. The concentrations of serum samples of interleukin 6, von Willebrand Factor, tissue Plasminogen Activator, and Plasminogen Activator Inhibitor-1 were studied. The cultures with serum of patients after coronavirus infection were incubated with N-acetylcysteine and Sulodexide to estimate their potential protective role. The blood inflammatory parameters were increased in the group of cultures incubated with serum from patients after coronavirus infection. Supplementation of the serum from patients after coronavirus infection with N-acetylcysteine or Sulodexide reduced the synthesis of interleukin 6 and von Willebrand Factor. No changes in the synthesis of tissue Plasminogen Activator were observed. N-acetylcysteine reduced the synthesis of Plasminogen Activator Inhibitor-1. N-acetylcysteine and Sulodexide increased the tPA/PAI-1 ratio. N-acetylcysteine may have a role in reducing the myocardial injury occurring in the post-COVID-19 syndrome. Sulodexide can also play a protective role in post-COVID-19 patients.

COVID-19 STEMI related to microthrombi may lead to coronary microvascular dysfunction

Coronavirus disease 2019 (COVID-19) increases the risk of ST-segment elevation myocardial infarction (STEMI), and is associated with a higher occurrence of nonobstructive coronary artery disease. We present a unique case of STEMI with concomitant COVID-19 infection in a young female found to have slow flow in multiple vessels on angiography, likely due to microvascular thrombi. Three months later, the patient developed coronary microvascular dysfunction (CMD), suggesting an evolution of microvascular thrombi and injury into subsequent CMD.

Tako-Tsubo syndrome in patients with COVID-19: a single-center retrospective case series

Growing evidence shows that COVID-19 is associated with an increase in Tako-Tsubo syndrome (TTS) incidence. We collected data from patients hospitalized in our multidisciplinary COVID-19 department who had a diagnosis of TTS during the second and third waves of the pandemic in Italy. We reported four cases of TTS associated with COVID-19. Except for COVID-19, no patient had any classical TTS triggers. The mean age was 72 years (67-81) and all patients had COVID-19-related interstitial pneumonia confirmed by computed tomography. Typical apical ballooning and transitory reduction in left ventricle (LV) systolic function with a complete recovery before discharge were observed in all patients. The mean LV ejection fraction at TTS onset was 42% (40-48%). The electrocardiogram showed ST-segment elevation in two cases, while an evolution with negative T waves and corrected QT prolongation was observed in all patients. Three patients underwent coronary angiography. Two patients had Alzheimer's disease. The time interval from hospital admission to TTS onset was 4 (2-6) days, and the time interval from COVID-19 symptom onset to TTS diagnosis was 10 (8-12) days. COVID-19 may be a trigger for TTS, though TTS pathophysiology in COVID-19 patients remains unclear, likely due to its multifactorial nature.

Unveiling the Enigma: Exploring the Intricate Link Between Coronary Microvascular Dysfunction and Takotsubo Cardiomyopathy

This review article delves into the intricate and evolving relationship between coronary microvascular dysfunction (CMD) and takotsubo cardiomyopathy (TCM), two intriguing cardiovascular conditions increasingly recognised for their potential interplay. We examine their characteristics, shared pathophysiological mechanisms, diagnostic challenges, and management strategies. Emerging evidence suggests a link between microvascular dysfunction and the development of TCM, leading to a deeper exploration of their connection. Accurate diagnosis of both conditions becomes essential, as microvascular dysfunction may modify TCM outcomes. We underscore the significance of understanding this connection for improved patient care, emphasising the need for tailored interventions when CMD and TCM coexist. Collaborative research and heightened clinical awareness are advocated to advance our comprehension of this relationship. Through interdisciplinary efforts, we aim to refine diagnostic precision, develop targeted therapies, and enhance patient outcomes in cardiovascular medicine.

Familial hypercholesterolemia: The nexus of endothelial dysfunction and lipoprotein metabolism in COVID-19

PURPOSE OF REVIEW

Patients with heterozygous familial hypercholesterolemia (HeFH) are at increased risk for COVID-19 cardiovascular complications in the acute phase of the infection. Elevated levels of LDL-C and often lipoprotein(a) are present from birth and lead to endothelial dysfunction, which is aggravated by a direct viral attack of the endothelial cells and their exposure to the toxic levels of circulating proinflammatory and prothrombotic mediators during the hyperinflammatory reaction typical of COVID-19.

RECENT FINDINGS

Evidence to date shows the benefit of lipid-lowering therapy in patients with COVID-19. In HeFH patients who are at much higher cardiovascular risk, the focus should, therefore, be on the effective lowering of LDL-C levels, the root cause of the greater cardiovascular vulnerability to COVID-19 infection in these patients. The ongoing use of statins and other lipid-lowering therapies should be encouraged during the ongoing COVID pandemic to mitigate the risk of cardiovascular complications from COVID-19, particularly in HeFH patients.

SUMMARY

Epidemiologic registry data show that the incidence of myocardial infarction is increased in SARS-CoV-2-infected HeFH patients. There is a need to study whether the risk for acute cardiovascular events is increased in the long-term and if there are changes in lipid metabolism after SARS-CoV infection(s) in patients with HeFH.

Home-Based Exercise Training in the Recovery of Multisystem Inflammatory Syndrome in Children: A Case Series Study

OBJECTIVE

To assess the potential therapeutic role of exercise on health-related quality of life, assessed by the Pediatric Outcomes Data Collection Instrument (PODCI), coronary flow reserve (CFR), cardiac function, cardiorespiratory fitness, and inflammatory and cardiac blood markers in multisystemic inflammatory syndrome in children (MIS-C) patients.

METHODS

This is a case series study of a 12-wk, home-based exercise intervention in children and adolescents after MIS-C diagnosis. From 16 MIS-C patients followed at our clinic, 6 were included (age: 7-16 years; 3 females). Three of them withdrew before the intervention and served as controls. The primary outcome was health-related quality of life, assessed PODCI. Secondary outcomes were CFR assessed by 13N-ammonia PET-CT imaging, cardiac function by echocardiography, cardiorespiratory fitness, and inflammatory and cardiac blood markers.

RESULTS

In general, patients showed poor health-related quality of life, which seemed to be improved with exercise. Additionally, exercised patients showed improvements in coronary flow reserve, cardiac function, and aerobic conditioning. Non-exercised patients exhibited a slower pattern of recovery, particularly in relation to health-related quality of life and aerobic conditioning.

CONCLUSIONS

Our results suggest that exercise may play a therapeutic role in the treatment of post-discharge MIS-C patients. As our design does not allow inferring causality, randomized controlled trials are necessary to confirm these preliminary findings.

COVID-19 as a trigger of Guillain-Barré syndrome: A review of the molecular mechanism

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a pandemic with serious complications. After coronavirus disease 2019 (COVID-19), several post-acute COVID-19 syndromes (PACSs) and long-COVID sequels were reported. PACSs involve many organs, including the nervous, gustatory, and immune systems. One of the PACSs after SARS-CoV-2 infection and vaccination is Guillain-Barré syndrome (GBS). The incidence rate of GBS after SARS-CoV-2 infection or vaccination is low. However, the high prevalence of COVID-19 and severe complications of GBS, for example, autonomic dysfunction and respiratory failure, highlight the importance of post-COVID-19 GBS. It is while patients with simultaneous COVID-19 and GBS seem to have higher admission rates to the intensive care unit, and demyelination is more aggressive in post-COVID-19 GBS patients. SARS-CoV-2 can trigger GBS via several pathways like direct neurotropism and neurovirulence, microvascular dysfunction and oxidative stress, immune system disruption, molecular mimicry, and autoantibody production. Although there are few molecular studies on the molecular and cellular mechanisms of GBS occurrence after SARS-CoV-2 infection and vaccination, we aimed to discuss the possible pathomechanism of post-COVID-19 GBS by gathering the most recent molecular evidence.

Atherosclerosis, Cardiovascular Disorders and COVID-19: Comorbid Pathogenesis

The article describes how atherosclerosis and coronavirus disease 19 (COVID-19) may affect each other. The features of this comorbid pathogenesis at various levels (vascular, cellular and molecular) are considered. A bidirectional influence of these conditions is described: the presence of cardiovascular diseases affects different individuals' susceptibility to viral infection. In turn, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can have a negative effect on the endothelium and cardiomyocytes, causing blood clotting, secretion of pro-inflammatory cytokines, and thus exacerbating the development of atherosclerosis. In addition to the established entry into cells via angiotensin-converting enzyme 2 (ACE2), other mechanisms of SARS-CoV-2 entry are currently under investigation, for example, through CD147. Pathogenesis of comorbidity can be determined by the influence of the virus on various links which are meaningful for atherogenesis: generation of oxidized forms of low-density lipoproteins (LDL), launch of a cytokine storm, damage to the endothelial glycocalyx, and mitochondrial injury. The transformation of a stable plaque into an unstable one plays an important role in the pathogenesis of atherosclerosis complications and can be triggered by COVID-19. The impact of SARS-CoV-2 on large vessels such as the aorta is more complex than previously thought considering its impact on vasa vasorum. Current information on the mutual influence of the medicines used in the treatment of atherosclerosis and acute COVID-19 is briefly summarized.

Coronary Flow Velocity Reserve by Echocardiography: Beyond Atherosclerotic Disease

Coronary flow velocity reserve (CFVR) is defined as the ratio between coronary flow velocity during maximal hyperemia and coronary flow at rest. Gold-standard techniques to measure CFVR are either invasive or require radiation and are therefore inappropriate for large-scale adoption. More than 30 years ago, echocardiography was demonstrated to be a reliable tool to assess CFVR, and its field of application rapidly expanded. Although initially validated to assess the hemodynamic relevance of a coronary stenosis, CFVR by echocardiography was later used to investigate coronary microcirculation. Microvascular dysfunction was detected in many different conditions, ranging from organ transplantation to inflammatory disorders and from metabolic diseases to cardiomyopathies. Moreover, it has been proven that CFVR by echocardiography not only detects coronary microvascular involvement but is also an effective prognostic factor that allows a precise risk stratification of the patients. In this review, we will summarize the many applications of CFVR by echocardiography, focusing on the coronary involvement of systemic diseases.

Exosomal miR-145 and miR-885 Regulate Thrombosis in COVID-19

We hypothesized that exosomal microRNAs could be implied in the pathogenesis of thromboembolic complications in coronavirus disease 2019 (COVID-19). We isolated circulating exosomes from patients with COVID-19, and then we divided our population in two arms based on the D-dimer level on hospital admission. We observed that exosomal miR-145 and miR-885 significantly correlate with D-dimer levels. Moreover, we demonstrate that human endothelial cells express the main cofactors needed for the internalization of the "Severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2), including angiotensin converting enzyme 2, transmembrane protease serine 2, and CD-147. Interestingly, human endothelial cells treated with serum from COVID-19 patients release significantly less miR-145 and miR-885, exhibit increased apoptosis, and display significantly impaired angiogenetic properties compared with cells treated with non-COVID-19 serum. Taken together, our data indicate that exosomal miR-145 and miR-885 are essential in modulating thromboembolic events in COVID-19. SIGNIFICANCE STATEMENT: This work demonstrates for the first time that two specific microRNAs (namely miR-145 and miR-885) contained in circulating exosomes are functionally involved in thromboembolic events in COVID-19. These findings are especially relevant to the general audience when considering the emerging prominence of post-acute sequelae of COVID-19 systemic manifestations known as Long COVID.

Non-Dipper Blood Pressure Impact on Coronary Slow Flow in Hypertensive Patients With Normal Coronary Arteries

OBJECTIVE

Coronary slow flow (CSF) is linked to myocardial ischemia, malignant arrhythmias, and cardiovascular mortality. On the other hand, hypertension (HTN) is an important risk factor for vascular disorders. There is limited research on the relationship between CSF and HTN. This study aimed to investigate TIMI frame count (TFC), which is an indicator of CSF, in dipper and non-dipper hypertensive individuals with normal coronary arteries.

METHODS

The study was conducted as a retrospective observational study. Patients diagnosed with CSF and dipper or non-dipper hypertension were included in this study. Blood tests were routinely conducted for all patients. ECG was conducted for each patient, and echocardiography was performed. Coronary artery images were obtained in the CAG laboratory. Blood pressure (BP) measurements were obtained from the ambulatory Holter records. The patients were separated into two groups based on ambulatory Holter monitoring. The relationship between CSF and HTN was also examined.

RESULTS

A total of 71 patients, comprising 25 women (37.2%) and 46 men (62.8%) with an average age of 52.75±9.42 years, were enrolled in the research. Based on ambulatory BP, the individuals were separated into two groups: non-dipper (n=36) and dipper (n=35). The pulse rate was significantly higher in the non-dipper group (p<0.001). In terms of mean systolic and diastolic blood pressure, there were no substantial differences across the groups (p = 0.326 and p = 0.654, respectively). The daytime mean systolic and diastolic BP did not significantly differ across the groups (p = 0.842 and p = 0.421). The dipper group had substantially lower nighttime systolic and diastolic BP values (p <0.001). The LAD, Cx, and RCA TIMI frame scores were significantly lower in the dipper group (p<0.001).

CONCLUSION

In this study, non-dipper patients had a greater CSF rate than dipper.

Long-term effect of SARS-CoV-2 infection on cardiovascular outcomes and all-cause mortality

Since the very beginning of the coronavirus disease 2019 (COVID-19) pandemic in early 2020, it was evident that patients with cardiovascular disease (CVD) were at an increased risk of developing severe illness, and complications spanning cerebrovascular disorders, dysrhythmias, acute coronary syndrome, ischemic and non-ischemic heart disease, pericarditis, myocarditis, heart failure, thromboembolic disease, stroke, and death. Underlying these was excessive systemic inflammation and coagulopathy due to SARS-COV-2 infection, the effects of which also continued long-term as evidenced by post-COVID-19 cardiovascular complications. The acute and chronic cardiovascular effects of COVID-19 occurred even among those who were not hospitalized and had no previous CVD or those with mild symptoms. This comprehensive review summarizes the current understanding of molecular mechanisms triggered by the SARS-CoV-2 virus on various cells that express the angiotensin-converting enzyme 2, leading to endothelial dysfunction, inflammation, myocarditis, impaired coagulation, myocardial infarction, arrhythmia and a multisystem inflammatory syndrome in children or Kawasaki-like disease.

Prognostic value of von Willebrand factor and ADAMTS13 in patients with COVID-19: A systematic review and meta-analysis

BACKGROUND

Endotheliopathy and coagulopathy appear to be the main causes for critical illness and death in patients with coronavirus disease 2019 (COVID-19). The adhesive ligand von Willebrand factor (VWF) has been involved in immunothrombosis responding to endothelial injury. Here, we reviewed the current literature and performed meta-analyses on the relationship between both VWF and its cleaving protease ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin type 1 motif, member 13) with the prognosis of COVID-19.

METHODS

We searched MEDLINE, Cochrane Library, Web of Science, and EMBASE databases from inception to 4 March 2022 for studies analyzing the relationship between VWF-related variables and composite clinical outcomes of patients with COVID-19. The VWF-related variables analyzed included VWF antigen (VWF:Ag), VWF ristocetin cofactor (VWF:Rco), ADAMTS13 activity (ADAMTS13:Ac), the ratio of VWF:Ag to ADAMTS13:Ac, and coagulation factor VIII (FVIII). The unfavorable outcomes were defined as mortality, intensive care unit (ICU) admission, and severe disease course. We used random or fixed effects models to create summary estimates of risk. Risk of bias was assessed based on the principle of the Newcastle-Ottawa Scale.

RESULTS

A total of 3764 patients from 40 studies were included. The estimated pooled means indicated increased plasma levels of VWF:Ag, VWF:Rco, and VWF:Ag/ADAMTS13:Ac ratio, and decreased plasma levels of ADAMTS13:Ac in COVID-19 patients with unfavorable outcomes when compared to those with favorable outcomes (composite outcomes or subgroup analyses of non-survivor versus survivor, ICU versus non-ICU, and severe versus non-severe). In addition, FVIII were higher in COVID-19 patients with unfavorable outcomes. Subgroup analyses indicated that FVIII was higher in patients admitting to ICU, while there was no significant difference between non-survivors and survivors.

CONCLUSIONS

The imbalance of the VWF-ADAMTS13 axis (massive quantitative and qualitative increases of VWF with relative deficiency of ADAMTS13) is associated with poor prognosis of patients with COVID-19.

The Effect of COVID-19 on the Perioperative Course of Acute Coronary Syndrome in Poland: The Estimation of Perioperative Prognosis and Neural Network Analysis in 243,515 Cases from 2020 to 2021

COVID-19 causes thromboembolic complications that affect the patient’s prognosis. COVID-19 vaccines significantly improve the prognosis for the course of the infection. The aim of this study was to evaluate the impacts of patient characteristics, including COVID-19 vaccinations, on perioperative mortality in acute coronary syndrome in Poland during the pandemic. We analyzed the data of 243,515 patients from the National Registry of Invasive Cardiology Procedures (Ogólnopolski Rejestr Procedur Kardiologii Inwazyjnej [ORPKI]). In this group, 7407 patients (21.74%) had COVID-19. The statistical analysis was based on a neural network that was verified by the random forest method. In 2020, the most significant impact on prognosis came from a diagnosis of unstable angina, a short period (<2 h) from pain occurrence to first medical contact, and a history of stroke. In 2021, the most significant factors were pre-hospital cardiac arrest, female sex, and a short period (<2 h) from first medical contact to coronary angiography. After adjusting for a six-week lag, a diagnosis of unstable angina and psoriasis were found to be relevant in the data from 2020, while in 2021, it was the time from the pain occurrence to the first medical contact (2−12 h) in non-ST segment elevation myocardial infarction and the time from first contact to balloon inflation (2−12 h) in ST-segment elevation myocardial infarction. The number of vaccinations was one of the least significant factors. COVID-19 vaccination does not directly affect perioperative prognosis in patients with acute coronary syndrome.

miR-142 Targets TIM-1 in Human Endothelial Cells: Potential Implications for Stroke, COVID-19, Zika, Ebola, Dengue, and Other Viral Infections

T-cell immunoglobulin and mucin domain 1 (TIM-1) has been recently identified as one of the factors involved in the internalization of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in human cells, in addition to angiotensin-converting enzyme 2 (ACE2), transmembrane serine protease 2 (TMPRSS2), neuropilin-1, and others. We hypothesized that specific microRNAs could target TIM-1, with potential implications for the management of patients suffering from coronavirus disease 2019 (COVID-19). By combining bioinformatic analyses and functional assays, we identified miR-142 as a specific regulator of TIM-1 transcription. Since TIM-1 has been implicated in the regulation of endothelial function at the level of the blood-brain barrier (BBB) and its levels have been shown to be associated with stroke and cerebral ischemia-reperfusion injury, we validated miR-142 as a functional modulator of TIM-1 in human brain microvascular endothelial cells (hBMECs). Taken together, our results indicate that miR-142 targets TIM-1, representing a novel strategy against cerebrovascular disorders, as well as systemic complications of SARS-CoV-2 and other viral infections.

The Relationship Between In-Hospital Mortality and Frontal QRS-T Angle in Patients With COVID-19

Background

Recent studies have demonstrated that the frontal QRS-T angle, defined as the angle between the mean QRS and T vectors, is a strong independent predictor of mortality in patients with cardiovascular disease and in the normal population. In this study, we aimed to investigate the relationship between frontal QRS-T angle and in-hospital mortality in COVID-19 patients.

Methods

A total of consecutive 532 patients with positive polymerase chain reaction (PCR) tests were enrolled. The patients were divided into two groups as in-hospital mortality and survival groups. Frontal QRS-T angle was automatically calculated from the admission electrocardiography (ECG).

Results

The median age in the study population was 62 (49-72) years and 273 (51.4%) of the patients were male. The median frontal QRS-T angle was 40 degrees (20-67 IQR) in the in-hospital mortality group, while it was 27 (11-48 IQR) in the survival group (p=0.001). In multivariable logistic regression analysis, frontal QRS-T angle was found to be an independent predictor of mortality (Odds ratio (OR):1.01, 95% Confidence interval (CI):1.00-1.02, p=0.036).

Conclusion

Frontal QRS-T angle, which was observed wider in the in-hospital mortality group, was found to be associated with in-hospital mortality in patients hospitalized for COVID-19.

The effect of coronavirus disease 2019 pneumonia on myocardial ischemia detected by single-photon emission computed tomography myocardial perfusion imaging

OBJECTIVE

We aimed to examine the effects of COVID-19 pneumonia on cardiac ischemia detected by myocardial perfusion imaging with single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) in patients presenting with chest pain and shortness of breath after recovery from COVID-19.

MATERIALS AND METHOD

Patients with a history of COVID-19 confirmed by reverse transcriptase-PCR test who underwent SPECT-MPI for the evaluation of ischemia with the complaints of chest pain and shortness of breath were screened for this study. Patients who underwent thorax CT during the acute period of the COVID-19 were included. Patients with and without pneumonia were determined based on computed tomographic criteria. The patients with a summed stress score of at least 4 on SPECT-MPI were considered to have abnormal MPI in terms of ischemia.

RESULTS

A total of 266 patients were included in the study. Sixty-five (24%) patients had ischemia findings on SPECT-MPI. Thorax CT showed pneumonia in 152 (57%) patients, and the patients were divided into two groups as pneumonia and nonpneumonia. Abnormal SPECT-MPI scores, which represented myocardial ischemia, were higher in the pneumonia group. Multivariate logistic regression analyses showed that the presence of hyperlipidemia and pneumonia on CT increased the risk of ischemia on SPECT-MPI (OR, 2.08; 95% CI, 1.08-3.99; P-value = 0.029; and OR, 2.90; 95% Cl, 1.52-5.54; P-value = 0.001, respectively).

CONCLUSION

COVID-19 pneumonia was identified as an independent predictor of ischemia on SPECT-MPI. Symptoms including chest pain and shortness of breath in patients who have had COVID-19 pneumonia may be attributed to coronary ischemia.

Coronary Microvascular Dysfunction is Common in Patients Hospitalized with COVID-19 Infection

Background and Aims

Microvascular disease is considered as one of the main drivers of morbidity and mortality in severe COVID‐19, and microvascular dysfunction has been demonstrated in the subcutaneous and sublingual tissues in COVID‐19 patients. The presence of coronary microvascular dysfunction (CMD) has also been hypothesized, but direct evidence demonstrating CMD in COVID‐19 patients is missing. In the present study, we aimed to investigate CMD in patients hospitalized with COVID‐19, and to understand whether there is a relationship between biomarkers of myocardial injury, myocardial strain and inflammation and CMD.

Methods

39 patients that were hospitalized with COVID‐19 and 40 control subjects were included to the present study. Biomarkers for myocardial injury, myocardial strain, inflammation, and fibrin turnover were obtained at admission. A comprehensive echocardiographic examination, including measurement of coronary flow velocity reserve (CFVR), was done after the patient was stabilized.

Results

Patients with COVID‐19 infection had a significantly lower hyperemic coronary flow velocity, resulting in a significantly lower CFVR (2.0 ± 0.3 vs. 2.4 ± 0.5, p < .001). Patients with severe COVID‐19 had a lower CFVR compared to those with moderate COVID‐19 (1.8 ± 0.2 vs. 2.2 ± 0.2, p < .001) driven by a trend toward higher basal flow velocity. CFVR correlated with troponin (p = .003, r: −.470), B‐type natriuretic peptide (p < .001, r: −.580), C‐reactive protein (p < .001, r: −.369), interleukin‐6 (p < .001, r: −.597), and d‐dimer (p < .001, r: −.561), with the three latter biomarkers having the highest areas‐under‐curve for predicting CMD.

Conclusions

Coronary microvascular dysfunction is common in patients with COVID‐19 and is related to the severity of the infection. CMD may also explain the “cryptic” myocardial injury seen in patients with severe COVID‐19 infection.

Pathophysiology of Cardiac Injury in COVID-19 Patients with Acute Ischaemic Stroke: What Do We Know So Far?-A Review of the Current Literature

With the onset of the COVID-19 pandemic, it became apparent that, in addition to pulmonary infection, extrapulmonary manifestations such as cardiac injury and acute cerebrovascular events are frequent in patients infected with SARS-CoV-2, worsening clinical outcome. We reviewed the current literature on the pathophysiology of cardiac injury and its association with acute ischaemic stroke. Several hypotheses on heart and brain axis pathology in the context of stroke related to COVID-19 were identified. Taken together, a combination of disease-related coagulopathy and systemic inflammation might cause endothelial damage and microvascular thrombosis, which in turn leads to structural myocardial damage. Cardiac complications of this damage such as tachyarrhythmia, myocardial infarction or cardiomyopathy, together with changes in hemodynamics and the coagulation system, may play a causal role in the increased stroke risk observed in COVID-19 patients. These hypotheses are supported by a growing body of evidence, but further research is necessary to fully understand the underlying pathophysiology and allow for the design of cardioprotective and neuroprotective strategies in this at risk population.

The SARS-CoV-2 Spike protein disrupts human cardiac pericytes function through CD147 receptor-mediated signalling: a potential non-infective mechanism of COVID-19 microvascular disease

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a broad range of clinical responses including prominent microvascular damage. The capacity of SARS-CoV-2 to infect vascular cells is still debated. Additionally, the SARS-CoV-2 Spike (S) protein may act as a ligand to induce non-infective cellular stress. We tested this hypothesis in pericytes (PCs), which are reportedly reduced in the heart of patients with severe coronavirus disease-2019 (COVID-19). Here we newly show that the in vitro exposure of primary human cardiac PCs to the SARS-CoV-2 wildtype strain or the α and δ variants caused rare infection events. Exposure to the recombinant S protein alone elicited signalling and functional alterations, including: (1) increased migration, (2) reduced ability to support endothelial cell (EC) network formation on Matrigel, (3) secretion of pro-inflammatory molecules typically involved in the cytokine storm, and (4) production of pro-apoptotic factors causing EC death. Next, adopting a blocking strategy against the S protein receptors angiotensin-converting enzyme 2 (ACE2) and CD147, we discovered that the S protein stimulates the phosphorylation/activation of the extracellular signal-regulated kinase 1/2 (ERK1/2) through the CD147 receptor, but not ACE2, in PCs. The neutralisation of CD147, either using a blocking antibody or mRNA silencing, reduced ERK1/2 activation, and rescued PC function in the presence of the S protein. Immunoreactive S protein was detected in the peripheral blood of infected patients. In conclusion, our findings suggest that the S protein may prompt PC dysfunction, potentially contributing to microvascular injury. This mechanism may have clinical and therapeutic implications.

The SARS-CoV-2 Spike protein disrupts human cardiac pericytes function through CD147 receptor-mediated signalling: a potential non-infective mechanism of COVID-19 microvascular disease

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a broad range of clinical responses including prominent microvascular damage. The capacity of SARS-CoV-2 to infect vascular cells is still debated. Additionally, the SARS-CoV-2 Spike (S) protein may act as a ligand to induce non-infective cellular stress. We tested this hypothesis in pericytes (PCs), which are reportedly reduced in the heart of patients with severe coronavirus disease-2019 (COVID-19). Here we newly show that the in vitro exposure of primary human cardiac PCs to the SARS-CoV-2 wildtype strain or the α and δ variants caused rare infection events. Exposure to the recombinant S protein alone elicited signalling and functional alterations, including: (1) increased migration, (2) reduced ability to support endothelial cell (EC) network formation on Matrigel, (3) secretion of pro-inflammatory molecules typically involved in the cytokine storm, and (4) production of pro-apoptotic factors causing EC death. Next, adopting a blocking strategy against the S protein receptors angiotensin-converting enzyme 2 (ACE2) and CD147, we discovered that the S protein stimulates the phosphorylation/activation of the extracellular signal-regulated kinase 1/2 (ERK1/2) through the CD147 receptor, but not ACE2, in PCs. The neutralisation of CD147, either using a blocking antibody or mRNA silencing, reduced ERK1/2 activation, and rescued PC function in the presence of the S protein. Immunoreactive S protein was detected in the peripheral blood of infected patients. In conclusion, our findings suggest that the S protein may prompt PC dysfunction, potentially contributing to microvascular injury. This mechanism may have clinical and therapeutic implications.

SPECT myocardial perfusion imaging identifies myocardial ischemia in patients with a history of COVID-19 without coronary artery disease

We aimed to examine the effect of a history of COVID-19 on myocardial ischemia in single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in patients who presented with shortness of breath and/or chest pain after recovery. For this single-center retrospective study, patients who presented at cardiology outpatient clinics and had SPECT-MPI were screened. A total of 1888 patients were included in the study, 340 of whom had a history of COVID-19. 64 patients with > 50% stenosis on coronary angiography were excluded from the study. The primary outcome of the study was abnormal MPI. In the study population, the median age was 56 (49–64 IQR) years, and 1127 (65%) of the patients were female. Abnormal MPI was detected in 77 patients (23%) in the COVID-19 group and in 244 patients (16%) in the non–COVID-19 group. After adjustment was performed for clinical predictors using Bayesian logistic regression, an important association was found between the presence of a confirmed prior COVID-19 infection and abnormal MPI (posterior median odds ratio, 1.70 [95% CrI, 1.20–2.40], risk difference, 9.6% [95% CrI, 1.8%, 19.7%]). In SPECT-MPI, ischemia rates were observed to be higher in COVID-19 group and it was found that a confirmed prior COVID-19 might predict of abnormal MPI.

Coronary microvascular dysfunction pathophysiology in COVID-19

Recently, accumulating evidence has highlighted the role of endothelial dysfunction in COVID-19 progression. Coronary microvascular dysfunction (CMD) plays a pivotal role in cardiovascular disease (CVD) and CVD-related risk factors (eg, age, gender, hypertension, diabetes mellitus, and obesity). Equally, these are also risk factors for COVID-19. The purpose of this review was to explore CMD pathophysiology in COVID-19, based on recent evidence. COVID-19 mechanisms were reviewed in terms of imbalanced renin-angiotensin-aldosterone-systems (RAAS), systemic inflammation and immune responses, endothelial dysfunction, and coagulatory disorders. Based on these mechanisms, we addressed CMD pathophysiology within the context of COVID-19, from five perspectives. The first was the disarrangement of local RAAS and Kallikrein-kinin-systems attributable to SARS-Cov-2 entry, and the concomitant decrease in coronary microvascular endothelial angiotensin I converting enzyme 2 (ACE2) levels. The second was related to coronary microvascular obstruction, induced by COVID-19-associated systemic hyper-inflammation and pro-thrombotic state. The third was focused on how pneumonia/acute respiratory distress syndrome (ARDS)-related systemic hypoxia elicited oxidative stress in coronary microvessels and cardiac sympathetic nerve activation. Fourthly, we discussed how autonomic nerve dysfunction mediated by COVID-19-associated mental, physical, or physiological factors could elicit changes in coronary blood flow, resulting in CMD in COVID-19 patients. Finally, we analyzed reciprocity between the coronary microvascular endothelium and perivascular cellular structures due to viremia, SARS-CoV-2 dissemination, and systemic inflammation. These mechanisms may function either consecutively or intermittently, finally culminating in CMD-mediated cardiovascular symptoms in COVID-19 patients. However, the underlying molecular pathogenesis remains to be clarified.