Lower-limb oedema
Is venous pressure raised? The IVC and RV answer in one view — then find why.
Echo approach, step by step
Bilateral oedema is cardiac when systemic venous pressure is raised. A normal-sized, collapsing IVC with a normal RV makes cardiac oedema unlikely. Then look for low oncotic pressure (liver, kidney, nutrition), drugs, venous insufficiency or hypothyroidism [3,201].
- IVCDiameter and collapse → RA pressure [3,50].
- RVSize, function, TAPSE; PASP [3,8].
- TRMechanism and severity [4].
- LVLVEF, filling pressure (left-sided HF causes right-sided congestion) [2,12].
- PericardiumConstriction (septal bounce, e′, hepatic vein reversal), effusion [57].
- Restrictive diseaseAmyloid features [30].
- Hepatic veinsSystolic reversal (severe TR) [4].
- IVC and RA pressure
- RV size and function
- PASP
- TR grade
- LVEF and filling pressure
- Constriction screen
- Amyloid screen
Causes & echo clues
| Cause | Echo clue | Next |
|---|---|---|
| Heart failure (HFrEF or HFpEF) | Low EF or raised filling pressure; dilated IVC | NT-proBNP, GDMT [12] |
| Severe TR / RV failure | Dilated RV and RA, TR, systolic hepatic reversal | TR pathway [6] |
| Pulmonary hypertension | High TR velocity, D-shaped LV | PH work-up [8] |
| Constriction | Septal bounce, preserved e′, expiratory hepatic reversal | CT, CMR [57] |
| Restrictive cardiomyopathy (amyloid) | Thick walls, low e′ | Amyloid work-up [30] |
| Hypoalbuminaemia (liver, nephrotic) | Normal IVC and RV | Albumin, urine protein [208] |
| Drugs (dihydropyridine CCB), venous insufficiency | Normal echo | Review drugs; venous duplex |
| Hypothyroidism | Pericardial effusion, bradycardia | TSH [201] |
Clinical pathway to the diagnosis
- Unilateral or bilateral? Pitting?Unilateral → venous duplex.
- JVP, hepatojugular reflux, ascites, lung crackles.
- BloodsNT-proBNP, albumin, creatinine, urine protein, LFTs, TSH [12].
- EchoIf the JVP is raised, NP is high or the cause is unclear [12].
- Drug reviewCalcium-channel blockers, NSAIDs, steroids, pioglitazone.
Clinical pearls & pitfalls
Practical tipThe IVC is the fastest discriminator. Small and collapsing → look outside the heart. Plethoric → cardiac, pericardial or TR [3].
- Constriction is misdiagnosed as liver disease for years. Check the JVP and the septal motion [57].
- Athletes and ventilated patients have large IVCs without raised RA pressure [3].
Red flags
- Unilateral, painful oedema → DVT (compression ultrasound) [124]
- Oedema with dyspnoea and orthopnoea → heart failure [12]
- Oedema with ascites and a raised JVP but normal EF → constriction, TR or restrictive disease [57]