Imaging Evaluation of Pulmonary and Non-Ischaemic Cardiovascular Manifestations of COVID-19

Abstract

Coronavirus Disease 2019 (COVID-19) has been a pandemic challenge for the last year. Cardiovascular disease is the most described comorbidity in COVID-19 patients, and it is related to the disease severity and progression. COVID-19 induces direct damage on cardiovascular system, leading to arrhythmias and myocarditis, and indirect damage due to endothelial dysfunction and systemic inflammation with a high inflammatory burden. Indirect damage leads to myocarditis, coagulation abnormalities and venous thromboembolism, Takotsubo cardiomyopathy, Kawasaki-like disease and multisystem inflammatory syndrome in children. Imaging can support the management, assessment and prognostic evaluation of these patients. Ultrasound is the most reliable and easy to use in emergency setting and in the ICU as a first approach. The focused approach is useful in management of these patients due its ability to obtain quick and focused results. This tool is useful to evaluate cardiovascular disease and its interplay with lungs. However, a detailed echocardiography evaluation is necessary in a complete assessment of cardiovascular involvement. Computerized tomography is highly sensitive, but it might not always be available. Cardiovascular magnetic resonance and nuclear imaging may be helpful to evaluate COVID-19-related myocardial injury, but further studies are needed. This review deals with different modalities of imaging evaluation in the management of cardiovascular non-ischaemic manifestations of COVID-19, comparing their use in emergency and in intensive care.

Keywords: cardiovascular involvement; cardiovascular magnetic resonance; coronavirus disease 2019; echocardiography; emergency; heart computerized tomography; intensive care; lung ultrasound; nuclear imaging; point-of-care ultrasonography.

Figure 1

COVID-19 heavily affects patients’ cardiovascular system: it can induce direct damages, leading to arrythmias and myocarditis, and indirect damages, mediated by cytokine storm, systemic vasculitis and vascular thrombosis. The indirect damage contributes to the development of myocarditis and leads to Kawasaki-like Disease and Multisystem inflammatory syndrome, coagulation abnormalities and venous thromboembolism, and Takotsubo cardiomyopathy. ACE2: Angiotensin Converting Enzyme 2; IFN-γ = interferon-γ, MCP1 = monocyte chemoattractant protein 1, MIP1-α = macrophage inflammatory protein 1-α; ROS = Reactive Oxygen Species; TMPRSS2: Transmembrane protease, serine 2; TNF-α = tumour necrosis factor-α.

Figure 2

Lung ultrasonography grading score is part of BLUE protocol for evaluation of dyspnoea in emergency setting. (A) Score 0: normal pattern, A-lines or <3 B-lines; (B) score 1: moderate loss, ≥3 B-lines; (C) score 2: severe loss, coalescent B-lines; (D) score 3: complete loss, white lung and/or lung consolidations. Legend: pleural line is indicated by star; A-lines are indicated by triangles; B-lines are indicated by continue lines; coalescent B-lines are indicated by dashed lines; Consolidation is indicated by circles, aerial bronchogram is indicated by arrow, while pleural effusion is indicated by stars.

Figure 3

Left heart evaluation needs a complete echocardiography evaluating parasternal long-axis (A) and apical 4 chamber (B) views. Using pulsed wave Doppler trans-mitral flow is evaluated (C). The apical 4 chamber view allows to perform tissue Doppler imaging analysis (D), able to make a doppler spectral analysis of the myocardial contraction velocity wave (E). A complete evaluation also includes the Speckle tracking evaluation to obtain the longitudinal strain (F). In particular the shown image was obtained in a 28-year old girl with a COVID-19 myocarditis.

Figure 4

Right heart evaluation needs an apical 4 chamber view (A) useful to detect the tricuspid regurgitation velocity (B) and the tricuspid annular plane excursion (TAPSE) (C). The parasternal short-axis view (D) allows another possible evaluation of tricuspid regurgitation as well as the pulmonary artery analysis (E). A right ventricle longitudinal strain (F) is possible in advanced imaging from an apical 4 chamber view.

Figure 5

CT scan is able to identify both gross pulmonary embolism (A,B) and tinier obstructions in subsegmental artery (C,D). Embolism (Circles) is not related to site of pneumonia but to endotheliitis and not to pulmonary inflammation (Triangles).

Figure 6

Viral replication and host immune response cooperate in disease progression. Through the three stages, different chest imaging modalities are useful to study the cardiovascular involvement. Transthoracic echocardiography (TTE) can identify left ventricle impairment as well as increased pulmonary hypertension and right ventricular dysfunction. Viral infection or to systemic inflammation can induce cardiovascular complications at different stages of the disease, inducing an increased risk for adverse outcome. To assess cardiovascular involvement specific multimodality imaging is required. CT: computed tomography; CTPA: computed tomography pulmonary arteriography; LUS: lung ultrasound; TTE: transthoracic echocardiography.