3.1 Baseline Clinical Characteristics
Of the initial 3,046 patients with COVID-19 enrolled in our study, 48 patients with no record of survival status, 29 patients without classification of disease severity, and 15 patients with suspected CAD but with no diagnosis were excluded. Among the final cohort of 2,954 patients, the median age was 60 years (range, 50-68 years), 1,461 (49.5%) were female, and 1,515 (51.3%) were severe/critical cases. The median hospital stay for severe/critical patients was significantly longer than that for mild/moderate cases. Compared with mild/moderate cases, severe/critical patients were more likely to experience chest congestion. Comorbidities were more prevalent among severe/critical patients compared to mild/moderate cases, including hypertension, diabetes, cardiovascular disease, cerebrovascular disease, cancer, and chronic obstructive pulmonary disease ( Table 1 ).
In terms of radiological and laboratory findings, severe/critical patients had more incidences of fuzzy boundaries and consolidation (Table 1) and significantly higher levels of C-reactive protein (CRP), D-dimer, interleukin-6 (IL-6), procalcitonin (PCT), and higher percentages of neutrophils (NEUT%), lymphocytes (LYM%), and monocytes (MONO%) within the first week of admission (Figure 1) . Serum cardiac markers, namely, BNP, hs-TNI, α-HBDH, CK-MB, and LDH, were also drastically elevated in severe/critical patients during the first week (Figure 1 ). In general, the results showed more pronounced activation of pathophysiological pathways in more severe cases of COVID-19.