From angiotensin-converting enzyme 2 disruption to thromboinflammatory microvascular disease: A paradigm drawn from COVID-19

Infectious diseases, cardio-cerebrovascular health and vaccines: pathways to prevention

Cardiovascular and infectious diseases both feature among the leading causes of death among men and women in the world. The pathophysiological pathways of infection and cardiovascular disease intersect, and there is a bidirectional relationship between the two. Vaccines are available for the most common infectious diseases affecting older adults, such as influenza, pertussis, pneumococcal disease, herpes zoster, COVID and respiratory syncytial virus (RSV). In many countries, these vaccines are recommended systematically for older adults and any adults with comorbidities, who are also those most likely to suffer from cardiovascular disease. There is a large body of evidence attesting to the benefits of vaccination on cardio- and cerebrovascular health. The European Interdisciplinary Council for Aging (EICA) and the Italian Society for Cardiovascular Prevention (Società Italiana per la Prevenzione Cardiovascolare, SIPREC) convened a 2-day meeting in June 2024 to review the state of the evidence on the relationship between cardio- and cerebrovascular health and the most common infectious diseases, and the role of vaccines in preventing both infection and its adverse consequences in terms of cardiovascular and cerebrovascular outcomes. We present here the Executive Summary of the proceedings of this meeting.

Choroidal vascularity ındex findings ın patients recovered from mild course COVID-19 pneumonia

PURPOSE

To assess the choroidal vascularity index (CVI) in individuals who have recovered from moderate pneumonia caused by COVID-19, using enhanced depth imaging optical coherence tomography (EDI-OCT).

METHODS

This study included 43 patients who had recovered from SARS-CoV-2 infection with mild pneumonia (Group 1-COVID group), as well as 45 healthy individuals (Group 2- healthy control group). The study comprised COVID-19 patients who fully recovered from COVID-19 pneumonia. These patients were assessed 6 months after their pneumonia had totally resolved. The measurements were acquired via EDI-OCT investigations of the choroidal structures. The primary measure of interest was the CVI, which is defined as the ratio of the luminal area (LA) to the total choroidal area (TCA).

RESULTS

Patients from Group 1 (COVID group) who had totally recovered exhibited significantly higher mean TCA, stromal area (SA), and LA compared to patients from Group 2 (control or healthy group). The two groups did not show a significant difference in CVI (p = 0.080).

CONCLUSION

Choroidal vascularity index can reveal the choroidal vascular physiology in patients who have fully recovered from COVID-19 pneumonia. EDI-OCT can be utilized to evaluate choroidal vascular alterations, serving as a non-invasive indicator for early vascular impairment following SARS-CoV-2 infection.

Evaluation of the early effects of the first-dose administration of the Sinovac vaccine on the retina, choroid, and optic disc using optical coherence tomography (OCT) and OCT-angiography

AIM

To determine the effects of the first-dose administration of the Sinovac vaccine on the retina, choroid, and optic disc in healthy participants.

METHODS

This prospective design study was conducted with 27 healthy healthcare workers who received the first dose of Sinovac vaccine and 25 healthy controls who were not vaccinated. In the vaccinated group, ophthalmological examinations and measurements were performed before vaccination and one week and one month after vaccination. Subfoveal, nasal, and temporal choroidal thicknesses (CTs), retinal nerve fiber layer (RNFL) thickness, and macular thickness (MT) were determined using spectral domain-optical coherence tomography at all visits. Superficial, deep, and peripapillary radial capillary plexus (superficial capillary plexus, deep capillary plexus (DCP), and radial peripapillary capillary, respectively), choriocapillaris vascular density, and foveal avascular zone parameters were measured on optical coherence tomography-angiography (OCT-A).

RESULTS

No significant difference was detected between the two groups in terms of the parameters measured by OCT and OCT-A (p > 0.05 for all). The CT values measured in all quadrants were significantly higher at the first week after vaccination (p < 0.05 for all), and they returned to their pre-vaccination values at the first month post-vaccination measurement (p > 0.05 for all). Concerning the RNFL and MT values, there was no significant difference between the pre-vaccination and post-vaccination first-week measurements (p > 0.05 for all), but a statistically significant increase was detected in the post-vaccination first-month MT and RNFL measurements (p < 0.05 for all). Only the decreases in the foveal DCP and choriocapillaris vascular density values were significant at the first week after vaccination (p < 0.05 for all).

CONCLUSION

The early changes detected after vaccination in this study suggest the possibility that autoimmune, vascular, and inflammatory diseases may simultaneously emerge in the early post-vaccination period or may be triggered after vaccination, or that the vaccine may unmask these diseases.

Border-Zone Cerebral Infarcts Associated with COVID-19 in CADASIL: A Report of 3 Cases and Literature Review

INTRODUCTION

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common inherited cerebral small vessel disease and is a cause of early onset ischemic lacunar stroke. COVID-19 infection may lead, in addition to acute respiratory syndrome, to vascular complications including stroke. Herein, we report three CADASIL patients presenting with cerebral border-zone infarcts concomitant to COVID-19 infection and summarize similar cases previously published in literature.

METHODS

Clinical and radiological features of the 3 patients were collected and described. A narrative review of literature was performed in PubMed and Google Scholar by the end of 2022 using the "CADASIL" AND "COVID-19" AND "stroke" terms.

RESULTS

In our 3 patients, aged 40-58 years, stroke symptoms occurred one to 11 days after the first COVID-19 manifestations. Pulmonary symptoms were mild or absent. One patient presented with hemodynamic failure presumably related to acute cardiomyopathy. Brain magnetic resonance imaging revealed in all cases, ischemic lesions within border-zone areas in both cerebral hemispheres, lesions in the genu of the corpus callosum or in the medium cerebellar peduncles in two cases. The watershed pattern of ischemic lesions was detected in two cases despite any blood pressure drop or severe respiratory dysfunction. Seven CADASIL patients presenting with acute brain infarcts (multiple in 4/7) in context of SARS-CoV-2 infection were identified in literature, despite no fall in blood pressure except for one of them.

CONCLUSION

Our observations, in line with previous reports, further suggest that COVID-19 infection may alter blood flow autoregulation in the deepest cerebral white matter in CADASIL patients. The thrombocytopathy and endotheliopathy developing during COVID-19 infection may participate to the underlying vascular processes.

Assessment of the optic nerve, macular, and retinal vascular effects of COVID-19

OBJECTIVE

To evaluate the effects of SARS-CoV-2 infection on the optic nerve, macula, and retinal vascular structures.

METHODS

This study included 129 participants recovering from COVID-19 and 130 healthy control subjects aged 18 to 55 years. The study was designed as observational and cross-sectional and was conducted between June 2020 and February 2021. The average thicknesses of the retinal nerve fibre layer (RNFL), ganglion cell complex (GCC), and macula also were measured using a spectral domain optical coherence tomography analysis. The vessel densities of the superficial and deep capillary plexuses of the macula, foveal avascular zone, and radial peripapillary capillary plexus of the optic disc were quantified by optical coherence tomography angiography.

RESULTS

In all quadrants, the RNFL and GCC were thinner in patients with neurologic symptoms of COVID-19 (p < 0.05). None of the measurements of the Early Treatment Diabetic Retinopathy Study regions significantly differed between patients with and without COVID-19 symptoms (p > 0.05). The foveal avascular zone area, perimeter, circularity index, and vessel densities (%) of the global and inner and outer circles of superficial capillary plexuses and deep capillary plexus and global and superior and inferior halves of the radial peripapillary capillary plexus measurements were found to significantly differ between the symptomatic COVID-19 group and the asymptomatic COVID-19 and control groups (p < 0.05).

CONCLUSION

RNFL and GCC thickness evaluation with optical coherence tomography and vessel density evaluation with optical coherence tomography angiography can be considered remarkable diagnostic methods for retinal neurovascular abnormalities and a biomarker for microvascular abnormalities after infection with SARS-CoV-2.

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.

Myositis als postakute Folge einer COVID-19-Erkrankung?

Es wird über eine an COVID-19 erkrankte Patientin mit Verdacht auf eine Myositis als Folge einer SARS-CoV-2-Infektion berichtet. Initial führte wenig Information über die Krankengeschichte zur erschwerten histopathologischen Interpretation. Im Verlauf konnten weitere Details eruiert und die Diagnose einer infektassoziierten thrombotischen Mikroangiopathie im Rahmen einer Morganella-morganii-Myositis gestellt werden. Der Fall zeigt, dass auch in Zeiten der allgegenwärtigen Pandemie und selbst bei positivem COVID-19-Test Differentialdiagnosen sowie der integrative klinisch-pathologische Ansatz bei der Befundung von Muskelbiopsien nicht außer Acht gelassen werden sollten.

Retinal microvascular morphology versus COVID-19: What to anticipate?

BACKGROUND

To investigate retinal microvascular morphological changes in previously COVID-19 infected patients using optical coherence tomography angiography (OCTA), and compare the findings to age- and gender-matched healthy subjects.

METHODS

In this cross-sectional study, OCTA findings (6.0 × 6.0 mm scan size and scan quality index ≥7/10) from previously COVID-19 infected patients (group 1, 32 patients, 64 eyes) with ≥1 month of complete recovery were compared to healthy subjects (group 2, 33 subjects, 66 eyes) with no history of COVID-19 infection. A positive real-time reverse transcription-polymerase chain reaction test on a naso-pharyngeal swab sample confirmed the diagnosis. The AngioVueAnalytics, RTVue-XR 2017.1.0.155 software measured and recorded OCTA parameters.

RESULTS

Group 1 had significantly lower superficial capillary plexus vessel densities in all foveal regions than group 2 (P<0.05). Foveal deep capillary plexus vessel density in group 1 was also significantly lower than in group 2 (P=0.009); however, no significant differences were found in other regions (P>0.05). All foveal avascular zone (FAZ) parameters were higher in group 1 than in group 2, with significant differences in FAZ area (P=0.019) and foveal vessel density 300 μm area around FAZ (P=0.035), but not FAZ perimeter (P=0.054). The outer retina and choriocapillaris flows were significantly lower in group 1 than in group 2 (P<0.05).

CONCLUSIONS

Prior COVID-19 infection seems to be associated with significant changes in retinal microvascular density, as well as FAZ and flow parameters, which may be attributed to different pathogenic mechanisms that lead to SARS-CoV-2 infection, such as thrombotic microangiopathy and angiotensin-converting enzyme 2 disruption.

Immunopathological changes, complications, sequelae and immunological memory in COVID-19 patients

Confirmed SARS-CoV-2-caused disease (COVID-19) cases have reached 275.65 million worldwide. Although the majority of COVID-19 patients present mild to moderate symptoms, some have severe complications including death. We first reviewed the pathogenesis on ACE2, a binding receptor of SARS-CoV-2 expressed in multiple organs, and prevalent multinucleate syncytia in the lung tissues of COVID-19 patients. Then, we evaluated the pathological, immunological changes and sequelae in the major organs. Finally, we reviewed the immunological memory after SARS-CoV-2 infection and vaccination. The binding of SARS-Cov-2 to ACE2 receptor results in reduced ACE2 protein levels, which may lead to elevated susceptibility to inflammation, cell death, organ failure, and potentially severe illness. These damages increase the risk of health problems over a long period, which result in many complications. The complications in multiple organs lead to the increased risk of long-term health problems that require additional attention. A multidisciplinary care team is necessary for further management and recovery of the COVID-19 survivors. Many COVID-19 patients will probably make antibodies against SARS-CoV-2 virus for most of their lives, and the immunity against reinfection would last for 3-61 months.

The state of complement in COVID-19

Hyperactivation of the complement and coagulation systems is recognized as part of the clinical syndrome of COVID-19. Here we review systemic complement activation and local complement activation in response to the causative virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and their currently known relationships to hyperinflammation and thrombosis. We also provide an update on early clinical findings and emerging clinical trial evidence that suggest potential therapeutic benefit of complement inhibition in severe COVID-19.

Neurological update: COVID-19

Coronavirus Disease 2019 is predominantly a disorder of the respiratory system, but neurological complications have been recognised since early in the pandemic. The major pathophysiological processes leading to neurological damage in COVID-19 are cerebrovascular disease, immunologically mediated neurological disorders and the detrimental effects of critical illness on the nervous system. It is still unclear whether direct invasion of the nervous system by the Severe Acute Respiratory Syndrome Coronavirus 2 occurs; given the vast numbers of people infected at this point, this uncertainty suggests that nervous system infection is unlikely to represent a significant issue if it occurs at all. In this review, we explore what has been learnt about the neurological complications of COVID-19 over the course of the pandemic, and by which mechanisms these complications most commonly occur.

The role of antirheumatics in patients with COVID-19

The COVID-19 pandemic has resulted in more than 2 million deaths globally. Two interconnected stages of disease are generally recognised; an initial viral stage and a subsequent immune response phase with the clinical characteristics of hyperinflammation associated with acute respiratory distress syndrome. Therefore, many immune modulators and immunosuppressive drugs, which are widely used in rheumatological practice, have been proposed as treatments for patients with moderate or severe COVID-19. In this Review, we provide an overview of what is currently known about the efficacy and safety of antirheumatic therapies for the treatment of patients with COVID-19. Dexamethasone has been shown to reduce COVID-19 related mortality, interleukin-6 inhibitors to reduce risk of cardiovascular or respiratory organ support, and baricitinib to reduce time to recovery in hospitalised patients requiring oxygen support. Further studies are needed to identify whether there is any role for glucocorticoids in patients with less severe COVID-19. Although evidence on the use of other antirheumatic drugs has suggested some benefits, results from adequately powered clinical trials are urgently needed. The heterogeneity in dosing and the absence of uniform inclusion criteria and defined stage of disease studied in many clinical trials have affected the conclusions and comparability of trial results. However, after the success of dexamethasone in proving the anti-inflammatory hypothesis, the next 12 months will undoubtedly bring further clarity about the clinical utility and optimal dose and timing of other anti-rheumatic drugs in the management of COVID-19.