Patients with COVID-19 who have higher levels of coronary artery calcium (CAC) face increased risk of death from the disease, according to research presented at the RSNA 2021 meeting.
The study findings could help clinicians assess the prognosis of COVID-19 patients, said Dr. Jaime Verdugo of the German Hospital of Santiago in Chile in his presentation.
"Recent studies have shown a close relationship between cardiovascular risk and [the evolution of disease in] infected patients," he said. "Imaging biomarkers such as CAC have an established role in cardiovascular disease risk stratification but might also provide prognostic information [for COVID-19 patients]. The purpose of our study was to evaluate the relationship between noncontrast chest CT findings and clinical outcomes in a representative sample of inpatients with COVID-19 pneumonia during the first wave of the pandemic in Chile."
As the COVID-19 pandemic has continued, research efforts have shifted somewhat from how best to diagnose the disease to how to predict its course and thus tailor treatment. In this vein, Verdugo and colleagues sought to explore any connections between noncontrast chest CT findings and clinical outcomes in a sample of 326 patients hospitalized with COVID-19 disease during the first wave of the pandemic in Chile, between May and June 2020.
Verdugo's group tracked patient demographics such as age, sex, and health insurance coverage, as well as risk factors (asthma, diabetes, chronic obstructive pulmonary disease, high blood pressure); clinical data such as symptom onset, positive polymerase chain reaction (PCR) date, and hospital admission/discharge dates; and whether the patient had been ventilated and how. The team also considered the following CT findings:
- Presence of organizing pattern
- Presence of coronary artery calcium
- Total volume and average density of pulmonary opacities
- Lung injury extent
- Average liver density
The study authors found that, of the patient cohort, 103 had coronary artery calcium, with a mean score of 486 Agaston units (AU) (scores higher than 300 indicate the person has a high risk of heart attack). They also found the following:
- 52.8% of patients had organizing pneumonia pattern.
- 22.2% had mediastinal lymph nodes.
- 31.1% had anterior descending artery coronary artery disease (CAD).
- 21.3% had circumflex CAD.
- 21.6% had right coronary artery CAD.
- 9% had left main CAD.
Those COVID-19 patients with no organizing pneumonia pattern, higher average density of pulmonary opacities, and coronary artery calcium in the left main and right coronary artery were at higher risk of death -- and for every 100 AU increase, their mortality risk increased by 5%, Verdugo noted.
"COVID-19 patients with CAC had a higher risk of dying, and the risk increased as Agaston score value climbed," he said. "[Our study suggests that determining] early prognostic factors [such as CAC score could help] tailor the treatment of COVID-19 patients."
In related research that used dual-energy CT to evaluate the long-term effects of COVID-19, presenter Dr. Martine Remy-Jardin, PhD, of the University Center of Lille in France, shared findings from a study that investigated the incidence of lung vascular abnormalities three months after patients with COVID-19 had been hospitalized, noting that COVID-19's manifestations go beyond pneumonia.
"The main manifestations of the disease are not only pneumonia but also coagulation disorders," she said.
The study included 320 patients with confirmed COVID-19 who were admitted to the hospital between March and April of 2020 and who underwent follow-up at three months post discharge, as well as 67 patients with ongoing respiratory symptoms after hospital discharge who were referred for follow-up. Of the total patient cohort, 55 underwent a dual-energy angiographic CT exam.
Of these 55, all had partial (72.7%) or complete (27.3%) resolution of COVID-19 lung infection. CT angiographic images were normal in 94.6% of patients; the remaining patients showed nonobstructive thrombi. Lung perfusion was abnormal in 65.5% of these patients, however: 58% of those patients with abnormal lung perfusion findings showed residual COVID-19 opacities, the group noted.
The findings suggest that clinicians should keep watch for lung abnormalities in COVID-19 patients, even months after these patients have recovered, Remy-Martin noted.
"Dual-energy CT depicted unexpected arterial thrombosis ... perfusion abnormalities suggestive of microangiopathy ... and areas of increased perfusion matching residual SARS-CoV-2 pneumonia abnormalities," she concluded.
