Isolated subclavian artery: an echocardiographic diagnosis and explanation of unusual four-limb blood pressures
Bibliographic record
Abstract
A full term, 3.2-kg girl presented with signs of cardiogenic shock and diminished pulses on the first day of life. The four-limb blood pressure showed a 30 mmHg gradient between the left and right arm (82/39 vs. 52/43 mmHg, respectively) but insignificant gradient with the right leg (76/44 mmHg). The echocardiogram revealed a left aortic arch with type B interruption and bilateral ductus arteriosus (PDA) with an isolated right subclavian artery (RSA) arising from the right pulmonary artery (RPA) via a tortuous ipsilateral PDA (Figure 1, panels A and B and Supplementary Data online, Videos S1 and S2). Computed tomography confirmed the anatomy (Figure 1, panels C and D). The patient went to the operating room where a successful repair of the interrupted arch and isolated artery was achieved. Post-operative echocardiogram confirmed laminar flow across the vessels. Transthoracic echocardiogram (top images, A and B) and CT 3D reconstruction (bottom images, C and D) of the patient. (A) 2D image from a suprasternal, coronal view showing the right subclavian artery (RSA) via a tortuous right ductus arteriosus (Yellow arrow). (B) Same, with colour Doppler. (C) Posterior view of the cardiac CT, 3D reconstruction. (D) Lateral view (from the right) of the cardiac CT, 3D reconstruction. L-PDA: left ductus arteriosus. LSA: left subclavian artery; MPA: main pulmonary artery; RPA: right pulmonary artery; Ao: ascending aorta; LPA, left pulmonary artery. The combination of an isolated RSA with an interrupted left aortic arch is very rare and almost always associated with 22q11.2 microdeletion. Embryologic explanation involves the regression/involution of three arch segments, between: (i) the right carotid artery and the RSA, (ii) the RSA and the descending aorta (hence the isolated RSA), and (iii) the left carotid and left subclavian artery (resulting in type B arch interruption). The unusual four-limb blood pressure was secondary to the tortuosity and restriction of the right PDA that gave rise to the RSA. The other limbs were perfused by a larger unrestrictive left PDA and therefore demonstrated higher systolic pressures. The echocardiogram correctly diagnosed the anatomy and the cause of this relevant finding. Supplementary data are available at European Heart Journal – Cardiovascular Imaging online.
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 | 0.007 |
| Meta-epidemiology (narrow) | 0.003 | 0.001 |
| Meta-epidemiology (broad) | 0.002 | 0.002 |
| Bibliometrics | 0.005 | 0.002 |
| Science and technology studies | 0.002 | 0.003 |
| Scholarly communication | 0.001 | 0.004 |
| Open science | 0.003 | 0.002 |
| Research integrity | 0.010 | 0.007 |
| Insufficient payload (model declined to judge) | 0.004 | 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".