Abstract 176: A simple, low resource approach to thrombus and blood collection for patients undergoing endovascular thrombectomy yields good RNA integrity

IntroductionGenomic research on thrombectomy samples is often resource‐intensive. We describe a streamlined workflow that reduces the need for extensive staff and materials in RNA extraction from these samples.MethodsThrombi and blood samples were collected from 9 patients with large vessel occlusion ischemic stroke. Demographic and clinical data were recorded. Blood samples were stored in EDTA tubes at 4°C until centrifugation, after which plasma and buffy coats were separated and frozen at ‐80°C. Thrombi were divided into a portion fixed in 10% formalin for 24‐48 hours, then transferred to 70% ethanol, and another portion initially stored at ‐20°C before being frozen at ‐80°C. RNA was extracted from the fresh frozen portion using a simple commercial kit, and RNA integrity numbers (RIN) were assessed.ResultsThe median patient age was 70 years (IQR 59‐78), and the median NIHSS score was 12 (IQR 7‐15). The median time from last known well‐to‐clot retrieval was 7.9 hours (IQR 6.3‐14.8), and the median time from sample collection‐to‐processing was 23.2 h (IQR 8.4‐34.5). Despite minimal resources, we achieved a median thrombi RIN score of 4.2 (IQR 2.8‐6.5) and a median blood RIN score of 5.2 (IQR 3.1‐6.5). Thrombi RIN scores showed a trend toward negative correlation with time from last known well‐to‐removal (r2=0.29, p=0.1), suggesting that longer delays may worsen RNA integrity. Blood RIN scores suggested a correlation with processing times (r2=0.40, p=0.06). No significant associations were found between RIN scores and demographic variables.ConclusionEndovascular labs can initiate genomic research on thrombectomy samples with limited resources. Blood samples are more sensitive to processing times, while thrombi may present RNA integrity challenges in cases with longer delays from last known well, a consideration for research on extended‐window cases. Further studies with larger sample sizes are needed to confirm these trends.