Pulse deficit & inter-arm BP difference
Acute: dissection until proved otherwise. Chronic: subclavian stenosis, coarctation or aortitis.
Echo approach, step by step
A pulse deficit or a large inter-arm pressure difference is a high-risk feature for acute aortic syndrome [9,203]. In the chronic setting, it suggests subclavian artery stenosis, coarctation or large-vessel vasculitis [25,174].
- Aortic root and ascending aortaFlap, dilatation, AR [9,173].
- SuprasternalArch and branch origins; descending aorta flap [173].
- CoarctationCW of the descending aorta: peak velocity with a diastolic tail [25].
- Aortic valveBicuspid (associated with coarctation and aortopathy) [9,25].
- PericardiumEffusion (type A dissection) [9].
- Abdominal aortaFlap, aneurysm [174].
- Root and ascending aorta
- Arch and descending aorta
- Coarctation Doppler
- Aortic valve morphology
- Effusion
- Abdominal aorta
Causes & echo clues
| Cause | Echo clue | Confirm |
|---|---|---|
| Aortic dissection | Flap, AR, effusion | CT angiography [9] |
| Coarctation | High descending velocity with diastolic tail; bicuspid valve | CT or CMR [25] |
| Subclavian stenosis | Normal heart | Duplex, CT [174] |
| Takayasu / giant-cell arteritis | Aortic wall thickening, AR | CT, MR, PET [174] |
| Embolic occlusion | LA or LV thrombus, AF, vegetation | Arterial imaging [176] |
Clinical pathway to the diagnosis
- Measure BP in both arms and one leg.
- Acute with pain→ ADD-RS, then CT angiography [174,203].
- ChronicArterial duplex, CT or MR angiography, inflammatory markers [174].
Clinical pearls & pitfalls
PitfallA pulse deficit with chest pain is a contraindication to thrombolysis until dissection is excluded [9].
- Always record BP in the arm with the higher reading in long-term management [26].
Red flags
- Acute onset with pain → aortic dissection (pulse deficit is an ADD-RS feature) [203]
- Neurological deficit with a pulse deficit → dissection involving the arch branches [9]
- Absent femoral pulses in a young hypertensive patient → coarctation [25]