Abstract

Aim: This study aimed to investigate the presence of SARS-CoV-2 RNA in atherosclerotic plaque and tissue samples obtained intraoperatively from patients with a history of COVID-19 who underwent coronary artery bypass grafting (CABG).
Material and Methods: This retrospective study included 235 patients with a documented history of COVID-19 who underwent CABG. Tissue samples were placed in tubes containing an RNA stabilization solution, incubated at 4–8°C for 8–12 hours, and then stored at −80°C until analysis. Reverse transcription and denaturation were performed at 55°C for 20 minutes and 95°C for 2 minutes, respectively. Amplification was conducted using the manufacturer’s recommended thermal cycling protocol: 95°C for 15 seconds, 55°C for 45 seconds, and 72°C for 15 seconds. Samples with at least one target gene showing a Ct value below 45 were considered positive.
Results: SARS-CoV-2 RNA was detected in tissue samples from six patients. The Ct values of the positive samples ranged from 34 to 40. Our findings suggest that SARS-CoV-2 RNA may persist in peripheral vascular tissues beyond the pulmonary system in patients with a history of COVID-19.
Conclusion: This observation may have prognostic implications regarding the systemic effects of the disease. The results highlight the need for further large-scale and long-term studies to elucidate the clinical significance of SARS-CoV-2 persistence in extrapulmonary tissues.

Key words: Severe acute respiratory syndrome coronavirus 2, COVID-19, coronary artery bypass grafting, vascular tissue, RNA detection, RT-PCR