CT Derived Pulmonary Vascular Measurements in COVID-19 Pneumonia and Correlation with the CT Severity Score, Oxygen Requirement and ICU Admission: An Indian Perspective

The novel 2019 coronavirus disease (COVID-19) has become a pandemic. Many studies have reported on the computed tomography (CT) manifestations of COVID-19, however, the pulmonary vascular enlargement has not been adequately examined. The present study aimed to measure the pulmonary arteries in COVID-19 patients and correlate the vascular metrics with the lung parenchymal abnormalities and admission to intensive care units. This is a retrospective study. All RT-PCR confirmed cases of COVID-19 of age more than 18 years, managed at the institute, either at COVID-19 ward or ICU, and whose scans were performed at the department from November 2020 to June 2021 were included in the study. Two radiologists evaluated the lung findings and the vascular measurements, and the clinical information was extracted from the charts and the hospital information system. All the data was tabulated in Microsoft Excel 2019, and ANOVA was used in SPSS 23.0 for statistical analysis. A total of 158 patients were included, 119 (75.3\%) being males and 39 (24.7\%) females with mean age 53.45 ± 15.3 years and 50.26 ± 14.59 years respectively (overall mean age 52.66 ± 15.17 years). The CT severity score and oxygen requirement significantly correlated with the main pulmonary artery diameter (\(p<.001\)). The main pulmonary artery to aorta diameter ratio (P/A ratio) was significantly higher in patients requiring ICU admission (30.4\% cases, mean ratio 0.88 ± 0.13), as opposed to those managed in ward (69.6\% cases, mean ratio 0.83 ± 0.13). MPA diameter was significantly higher in patients requiring oxygen as compared to those who did not (\(p=0.023\)). Higher P/A ratio is associated with ICU admissions in COVID-19 patients. Larger main pulmonary artery diameter is associated with increased oxygen requirement and with the CT severity score.