Abstract WP239: Real Time Prospective Measurement of aPTT Predicts Paradoxical Embolism in Cryptogenic Stroke
Bibliographic record
Abstract
Patent foramen ovale (PFO) is an important underlying source of cryptogenic stroke (CS) associated with hematologic procoagulability. However, the association of genetically identified hyperocagulability and paradoxical embolism has been difficult to establish due to retrospective analysis and the limited numbers of of known genetically identified hypercoagulable conditions. In this study, we explored the utility of conventional coagulation status in PFO related stroke, as the patients may harbor genetically unidentified hyperocoagulable conditions. Method: Eligible pts were prospectively recruited in accordance with IRB, and underwent conventional coagulation testing (PT/PTT) testing within 12 hours of stroke. All patients underwent full cryptogenic workup such as MRI/MRA, mobile cardiac outpatient telemetry (>30 days), cardiac echo, and hypercoagulable testing. Results: We screened 4,831 pts admitted with acute neurologic diseases, and recruited 358 eligible acute ischemic stroke pts. 54 (15.1%) pts had CS and 32 pts had PFO related stroke. While there is no difference between PFO-related CS and PFO-unrelated CS on full hypercaogulable screen (protein S, protein C, FVL, PTGM, ATIII, APLAb, LA, hcy), aPTT was statistically significantly shortened in PFO-related stroke patients (PFO CS vs. non-PFO CS: aPTT 27.2±4.1s vs. 29.9±2.3s). ROC curve indicates early shortened aPTT can predict PFO related stroke (sensitivity 70%, specificity 81.5%, p=0.017) (see Figure). Conclusion: We found real time aPTT to be significantly shortened in patients eventually diagnosed with paradoxical embolism related to PFO. While studies in larger pt cohorts accounting for other potential confounders are underway, this proof-of-concept study demonstrates the importance and utility of early conventional coagulation testing in identifying paradoxical embolism. Pts with shortened aPTT may need additional workup for other underlying hypercoagulable conditions.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".