Spontaneous coronary artery dissection: insights from intravascular ultrasound
Bibliographic record
Abstract
Abstract Introduction Spontaneous Coronary Artery Dissection (SCAD) may be at the origin of up to 25% of acute coronary events in women <50 yo with no or few risk factors. The diagnosis of SCAD is challenging and in some cases it may be ascertained only by intracoronary imaging such as intravascular ultrasound (IVUS) or optical coherence tomography (OCT). IVUS is widely available and has a better depth penetration compared to OCT, showing the extent of the false lumen and the aspect of the adventitia but its lower resolution does not always allow the visualization of smaller structures such as fenestrations. In a previous study we investigated the role of OCT in understanding the pathophysiology of SCAD and we reported a number of OCT complications. It is not known if these also apply to IVUS but since IVUS does not require additional contrast injection, the risk of false lumen (FL) propagation should be lower. Aim of the study To analyze the value of IVUS in the assessment of key features of SCAD and to explore the feasibility of three-dimensional (3D) reconstruction using IVUS imaging. Methods We collated the imaging findings of 15 cases of SCAD for which IVUS was used as part of routine clinical care. Images were assessed to determine the visualisation of the true lumen, the false lumen extent and its contents, the intima-media membrane, the presence of fenestrations, the external elastic lamina and underlying adventitia. Furthermore, we performed a 3D reconstruction of a type 2a dissection of the right coronary artery. The IVUS images were exported in DICOM format. The segmentation of the true and false lumens in the regions of interest was manually done using the ImageJ software. Subsequent images were processed using 3D Slicer and Paraview in order to obtain the 3D reconstruction of the dissected segment. Results The false lumen was entirely visible in 13/15 cases (87%) and the external elastic lamina in 12/15 cases (80%). In 3/15 cases (20%) the dissection was circumferential. The false lumen content had lower echogenicity compared to the surrounding tissue in all 15 cases. There was no visible fenestration. The 3D reconstruction (Figure 1) showed that the false lumen was larger than the true lumen. The general cross-sectional appearance was that of a “horseshoe” dissection but there was also a short segment of circumferential dissection and the intima-media membrane looked thickened. Conclusion Despite its resolution being lower than OCT, IVUS has a deep penetration and provides adequate imaging of the key features of SCAD. Perspectives We plan to further expand these findings in a larger series, intending to better characterize the false lumen and the adventitia in SCAD. IVUS findings in SCAD, 3D reconstruction Funding Acknowledgement Type of funding source: None
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 | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
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".