Association between circulating levels of miR-29 and postoperative neurological complications in acute type A aortic dissection patients.

Objectives: Postoperative neurological complications (PONC), which are associated with substantial morbidity and mortality, represent a prevalent clinical challenge following surgical repair of acute type A aortic dissection (AAD). This study aimed to identify novel biomarkers for the early diagnosis of PONC, facilitating timely clinical intervention. Methods: We established deep hypothermic circulatory arrest (DHCA) rat models, extracted total RNA from the hippocampus of rats (DHCA and control groups), performed microRNA (miRNA) sequencing, screened for differentially expressed genes (DEGs) between the two groups, and analysed their associated biological processes and pathways. A cohort of 95 patients with AAD was included in this study. Comprehensive clinical assessments and a standardized neuropsychological test battery were systematically conducted. Serum miR-29 levels were quantified via reverse transcription quantitative real-time polymerase chain reaction. Results: Transcriptomic profiling of the rat hippocampus under DHCA/cardiopulmonary bypass (CPB) revealed 31 differentially expressed miRNAs (FC > 1.5, Conclusions: This study identified dysregulated miR-29 as a key mechanism linked to PONC after CPB/DHCA and validated circulating miR-29b-3p as an independent predictor of PONC and mortality in AAD patients, providing a basis for early risk assessment.