Case presentation
A 67-year-old female with a history of obesity, gastric acid reflux disease, and hiatal hernia repair presented with persistent chest pain of 1-day duration. Her husband had weakness and fatigue of 1-week duration. Laboratory testing is presented in Figure . Given exposure to her husband who had non-specific symptoms, nasal swab testing for the SARS-CoV-2 was done which returned positive. She did not have respiratory symptoms, hypoxia, or fevers suggestive of COVID-19 pneumonia. Chest radiography showed clear lung fields (Figure Panel A) . She was admitted for a non-ST elevation myocardial infarction. Cardiac catheterization revealed severe three-vessel coronary artery disease (CAD), a culprit lesion in a large branching first diagonal with complete occlusion and grade 2 left to left collaterals; diffuse, severe, proximal and mid-left anterior descending artery CAD, and severe proximal right coronary artery CAD. There was severe distal left circumflex and left posterior descending artery CAD. Echocardiography revealed normal ventricular function and wall motion.
In the setting of continued symptoms from the acute coronary syndrome and multivessel CAD, cardiac surgical consultation was requested. Laboratory testing to identify inflammatory markers elevations associated with COVID-19 were normal; Figure. Computed tomographic (CT) chest imaging confirmed clear lung fields without pulmonary parenchymal pathology (Figure Panel B) . After ruling out active COVID-19 infection, we decided to proceed with CABG surgery.
Following uneventful induction of general anesthesia, aorta-bicaval cannulation was utilized for cardiopulmonary bypass. Myocardium was protected with cold blood cardioplegia. Coronary revascularization was performed with an in situ left internal mammary arterial graft to the left anterior descending artery, saphenous venous graft to the first diagonal, and saphenous venous graft to the left posterior descending artery. The patient was weaned from cardiopulmonary bypass without difficulty and transferred to the ICU. She was extubated within 4 hours of ICU admission and transitioned to nasal cannula oxygen at 2 L/min. Acute blood loss anemia was managed with transfusion\souts. Post-operative day 1 chest radiograph showed atelectasis which was managed with incentive spirometry and pain control. Subsequent radiographs showed the development of bilateral small pleural effusions (Figure Panel C), accompanied by the requirement for increase in nasal oxygen support to 5 L/min. The effusions were successfully treated with furosemide. The patient was then transferred to the step-down unit on post-operative day 4. She was afebrile during this period with no significant laboratory abnormalities. Respiratory status continued to improve, with improvement in chest radiography findings and nasal oxygen support was gradually weaned off (Figure Panel D ). The patient was discharged home on post-operative day 6.