Revisiting One of the Dreaded Outcomes of the Current Pandemic: Pulmonary Embolism in COVID-19

Advanced Imaging Supports the Mechanistic Role of Autoimmunity and Plaque Rupture in COVID-19 Heart Involvement

The cardiovascular system is frequently affected by coronavirus disease-19 (COVID-19), particularly in hospitalized cases, and these manifestations are associated with a worse prognosis. Most commonly, heart involvement is represented by myocarditis, myocardial infarction, and pulmonary embolism, while arrhythmias, heart valve damage, and pericarditis are less frequent. While the clinical suspicion is necessary for a prompt disease recognition, imaging allows the early detection of cardiovascular complications in patients with COVID-19. The combination of cardiothoracic approaches has been proposed for advanced imaging techniques, i.e., CT scan and MRI, for a simultaneous evaluation of cardiovascular structures, pulmonary arteries, and lung parenchyma. Several mechanisms have been proposed to explain the cardiovascular injury, and among these, it is established that the host immune system is responsible for the aberrant response characterizing severe COVID-19 and inducing organ-specific injury. We illustrate novel evidence to support the hypothesis that molecular mimicry may be the immunological mechanism for myocarditis in COVID-19. The present article provides a comprehensive review of the available evidence of the immune mechanisms of the COVID-19 cardiovascular injury and the imaging tools to be used in the diagnostic workup. As some of these techniques cannot be implemented for general screening of all cases, we critically discuss the need to maximize the sustainability and the specificity of the proposed tests while illustrating the findings of some paradigmatic cases.

Secondary Infections in Patients with COVID-19 Pneumonia Treated with Tocilizumab Compared to Those Not Treated with Tocilizumab: A Retrospective Study at a Tertiary Hospital in Kenya

INTRODUCTION

From the first case of SARS-Co-2 in Wuhan, China, to the virus being declared as a pandemic in March 2020, the world has witnessed morbidity and mortality on a global scale. Scientists have worked at a record pace to deliver a vaccine for the prevention of this deadly disease. Tocilizumab, an interleukin-6 (IL-6) blocker, received an emergency use authorization (EUA) by the Federal Drug Agency (FDA) in June 2021.

METHODS

This retrospective observational cohort study was conducted at the Aga Khan University Hospital, Nairobi, from March 8, 2020, to December 31, 2020. All patients with PCR confirmed COVID-19 pneumonia were included. Data were obtained from the medical records, and the admission registry was used to identify the patients, and both their electronic and paper-based files were retrieved from the medical records. Patient demographic data, medical history, baseline comorbidities, clinical characteristics, and outcome data were collected to study the infectious complications of Tocilizumab in patients affected by COVID-19 pneumonia.

RESULTS

A total of 913 patients who were diagnosed with COVID-19 were included. The overall superinfection infection rate among the COVID-19 patients was 6%. Superinfection in patients who received the Tocilizumab was 17.2% and in the non-Tocilizumab group was 4.8%. The superinfection rate among severe and critically ill patients was even higher at 41.8% and 69.9% (Tocilizumab group) and 2.1% and 11.8% (non-Tocilizumab group), respectively (p < 0.001). There was no difference in mortality observed between the groups (p = 0.846). Infection among HIV co-infection was very low at 2.3%.

CONCLUSION

Contrary to some studies, a higher rate of infection was observed among the Tocilizumab group, and no difference in mortality was observed between Tocilizumab and the non-Tocilizumab group. Infection among patients with HIV remains low in this susceptible population.