key: cord-0979498-z9opvznb
authors: Erdoğan, Mehmet; Öztürk, Selçuk; Erdöl, Mehmet Akif; Kasapkara, Ahmet; Beşler, Muhammed Said; Kayaaslan, Bircan; Hasanoğlu, İmran; Durmaz, Tahir; Güner, Rahmet
title: Prognostic utility of pulmonary artery and ascending aorta diameters derived from computed tomography in COVID‐19 patients
date: 2021-08-06
journal: Echocardiography
DOI: 10.1111/echo.15170
sha: 254ce2597221d977be3ae0f9710ae6f3d0093417
doc_id: 979498
cord_uid: z9opvznb

AIM: Chest computed tomography (CT) imaging plays a diagnostic and prognostic role in Coronavirus disease 2019 (COVID‐19) patients. This study aimed to investigate and compare predictive capacity of main pulmonary artery diameter (MPA), ascending aorta diameter (AAo), and MPA‐to‐AAo ratio to determine in‐hospital mortality in COVID‐19 patients. MATERIALS AND METHODS: This retrospective study included 255 hospitalized severe or critical COVID‐19 patients. MPA was measured at the level of pulmonary artery bifurcation perpendicular to the direction of the vessel through transverse axial images and AAo was measured by using the same CT slice at its maximal diameter. MPA‐to‐AAo ratio was calculated by division of MPA to AAo. RESULTS: Multivariate logistic regression model yielded MPA ≥29.15 mm (OR: 4.95, 95% CI: 2.01–12.2, p = 0.001), MPA (OR: 1.28, 95% CI: 1.13–1.46, p < 0.001), AAo (OR: .90, 95% CI: .81–.99, p = 0.040), and MPA‐to‐AAo ratio ≥.82 (OR: 4.67, 95% CI: 1.86–11.7, p = 0.001) as independent predictors of in‐hospital mortality. Time‐dependent multivariate Cox‐proportion regression model demonstrated MPA ≥29.15 mm (HR: 1.96, 95% CI: 1.03–3.90, p = 0.047) and MPA (HR: 1.08, 95% CI: 1.01–1.17, p = 0.048) as independent predictors of in‐hospital mortality, whereas AAo and MPA‐to‐AAo ratio did not reach statistical significance. CONCLUSION: Pulmonary artery enlargement strongly predicts in‐hospital mortality in hospitalized COVID‐19 patients. MPA, which can be calculated easily from chest CT imaging, can be beneficial in the prognostication of these patients.

A new infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and named as the Coronavirus disease 2019 has become a threatening health crisis, since December 2019. Because the infection spread globally in a very short time, COVID-19 was characterized as a pandemic in March 2020. 1 primarily affects the lungs and respiratory system. Besides, it has detrimental effects on vascular endothelium by impairing its functional and structural integrity. 1, 2 Chest computed tomography (CT) imaging plays a diagnostic and prognostic role in COVID-19 patients, and therefore, it is widely used in both diagnosed and suspected COVID-19 patients in order to examine the lungs and for risk stratification. 3 Indices derived from chest CT such as main pulmonary artery diameter (MPA), ascending aorta diameter (AAo), and MPA-to-AAo ratio were shown to be useful parameters for predicting clinical outcomes in various lung diseases 4, 5 and COVID-19. 6, 7 For instance, increased MPA-to-AAo ratio was associated with the severity of lung involvement 6 and enlarged MPA was associated with death in COVID-19 patients. 7 This study aimed to investigate and compare predictive capacity of MPA, AAo, and MPA-to-AAo ratio to determine in-hospital outcomes in a relatively large COVID-19 patient population.

The study was designed in a retrospective fashion and included con- The multicollinearity assessment was performed by correlation r coefficient value. Independent variables with correlation r coefficient above .7 were considered to comprise multicollinearity and were not evaluated in the same model. The results of regression analysis were reported with odds ratio (OR), hazard ratio (HR) and 95% CI. A two-tailed pvalue lower than 0.05 was considered to be statistically significant.

After the application of exclusion criteria, the remaining 255 patients

were categorized according to their survival status namely survivor (n = 199) and non-survivor (n = 56). The mean age of the overall study cohort was 55±19 years and 52% of the patients were male.

Hypertension was the most common comorbidity with a percentage of 37%. Myalgia or fatigue, cough, dyspnea, and fever were the most frequent admission symptoms, respectively. 

Patients treated with antiviral agents, antibiotic therapy, corticosteroids, anticoagulant therapy were more frequent in non-survivor group, whereas the percentage of patients treated with hydroxychloroquine was higher in survived group.

During follow-up, the rate of patients that needed ICU stay and invasive mechanical ventilation were 38% and 23%, respectively, in the whole study group and the median length of hospitalization period was 12.0 days (IQR 8.0-17.0). The percentage of patients that required ICU stay and invasive mechanical ventilation significantly differed (p < 0.001 for both) but length of hospitalization was similar between survivor and non-survivor groups (p = 0.31) ( Table 1 ).

Glucose, creatinine, aspartate amino transferase, ferritin, CRP, hs-TnI, white blood cell, and neutrophil levels were significantly higher in nonsurvivor group. On the other hand, sodium, albumin levels, lymphocyte count, and hemoglobin levels were significantly lower in non-survivor group patients. Platelet count was comparable between groups.

CT scanning was normal in 13% of the patients and significantly differed between groups. The percentage of patients with bilateral ground glass opacity, pleural effusion, and fibrotic changes were significantly higher in non-survivor group, whereas unilateral ground-glass opacity was significantly higher in survivor group. Patchy infiltration was comparable between groups. MPA, AAo, and MPA-to-AAo ratio calculations were significantly higher in non-survivor group compared to survivor group (p < 0.001 for all) ( sensitivity and 67% specificity. The cut-off value of MPA-to-AAo ratio (.82) was associated with 61% sensitivity and 69% specificity ( Figure 2 and Table 3) .

Optimal cutoff value of each CT-based main pulmonary artery diameter, ascending aortic diameter and MPA/AAo ratio measurements predicting for in-hospital mortality 

Receiver operating characteristic (ROC) curve analyses were conducted in order to determine and compare the optimal cut-off values of main pulmonary artery diameter (MPA), ascending aorta diameter (AAo) and MPA-to-AAo ratio that predict in-hospital mortality

Cumulative survival rates were calculated as 43% and 92% for MPA ≥29.15 mm and MPA < 29.15 mm, respectively (p < 0.001), 66% and 86% for AAo ≥34 mm and AAo < 34 mm, respectively (p = 0.33), and 65% and 86% for MPA-to-AAo ratio ≥.82 and MPA-to-AAo ratio < .82, respectively (p = 0.04) (Figure 3-5) .

Multivariate binary logistic regression model yielded MPA (Table 4 ).

Besides being a primary lung disease, COVID-19 is an infectious pathology that also disrupts the endothelial system by activating numerous inflammatory and prothrombotic cascades. Acute lung injury and respiratory distress syndrome is the most severe form of the disease and associated with impairments in pulmonary vasculature functioning. Therefore, alterations in pulmonary hemodynamics and vascular anatomy and development of pulmonary hypertension (PH) might provide prognostic clues in COVID-19 patients. Evidence coming from various patient populations underlies that enlargement of pulmonary arteries, which can be calculated easily by CT scanning, is a parameter that helps to predict adverse outcomes. 9, 10 In parallel, in our study which comprises a relatively large patient population, we found that pulmonary artery enlargement predicts in-hospital mortality in COVID-19 patients. MPA both as a continuous and categorical variable predicted in-hospital mortality in various regression models.

Mortality rates in severe COVID-19 patients hospitalized in intensive care units may vary depending on various factors. In the early stages of the pandemic, mortality rates of up to 65% have been

reported. 11 Mortality rates may vary due to factors such as regional experiences, different treatment strategies between countries and health care systems. In addition, these mortality rates, which were higher in the early stages of the pandemic, have decreased gradually, thanks to the increasing experience and health care support and have decreased to approximately 20% nowadays. 11 

There are several limitations of this study that need to be mentioned.

This was a single center, retrospective, and non-randomized study.

Our study cohort included hospitalized severe or critical patients with chest CT imaging and for this reason these results cannot be generalized to all COVID-19 patients. In addition, MPA and AAo calculations were performed through non-contrast CT imaging and without electrocardiography gating. Our study lacks data from transthoracic echocardiography and right heart catheterization that could make us to yield more firm conclusions about hemodynamic status and pulmonary artery enlargement. Furthermore, we lacked data of previous CT scanning which hindered us to suggest that pulmonary artery enlargement occurred subsequent to SARS-CoV-2 infection. Besides, follow-up CT scanning could give more beneficial results.

Pulmonary artery enlargement strongly predicts in-hospital mortality in hospitalized COVID-19 patients. MPA, which can be calculated easily from chest CT imaging, can be beneficial in the prognostication of these patients.

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COVID-19 is, in the end, an endothelial disease

Chest CT features of the novel coronavirus disease (COVID-19)

CT-determined pulmonary artery to aorta ratio as a predictor of elevated pulmonary artery pressure and survival in idiopathic pulmonary fibrosis

CT scan-measured pulmonary artery to aorta ratio and echocardiography for detecting pulmonary hypertension in severe COPD

The association of CT-measured cardiac indices with lung involvement and clinical outcome in patients with COVID-19

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Prognostic utility of pulmonary artery and ascending aorta diameters derived from computed tomography in COVID-19 patients

None.

The authors received no financial support for the research, authorship, and/or publication of this article.

None declared.

Mehmet Akif Erdöl MD https://orcid.org/0000-0002-2721-440X