A 65 year old man in your ICU has had a myocardial infarction 7 days ago and undergoes an transthoracic echocardiogram. As you perform your echo, something catches your eye at the LV Apex. You decide to focus in on it. What is this suspicious of?
You remain unsure, and ask a colleague. She suggests applying some colour flow over it……
Several weeks later, the patient is being followed up and you perform a further echocardiogram.
You diagnose a large apical left ventricular thrombus. Thrombus forms in the LV at sites of stasis (e.g. dyskinetic or akinetic myocardium and aneurysm) or low flow (e.g. dilated cardiomyopathy with EF <20%). Inflamed endothelium is also a major risk factor, so the combination of akinesia and inflammation that occurs post large infarction makes this group particularly at risk for LV thrombus. Hyper coagulable states by themselves may also rarely result in thrombus. Other important risk factors are foreign bodies, such as around LVAD inflow cannulae.
LV thrombosis is important to diagnose as these patients are at risk of embolic phenomena, particular if the thrombi are large and independently mobile. Thrombus also tends to propagate if left untreated.
Echocardiographic features:
- Hyperechoic (if older) or hypoechoic (if acute) masses
- Convex usually but can be sessile.
- Distinct from the endocardial border (can be hard to determine)
- Apex is the most common site but can occur anywhere.
- Lamination if more chronic
- More common in patients with akinesis/dykinesis post large infarction, dilated cardiomyopathies, foreign bodies i.e. LVADs, or hyper coagulable states.
The main differentials include normal endocardium, and other variants such as trabeculations and redundant chordae – see intracardiac masses for a great overview. Here are some tips on how to distinguish these:
- Zoom on apex
- Visualise area from at least two planes, and often non standard views are needed.
- High frequency probes i.e. 5-7.5Mhz
- Colour doppler
- Contrast e.g. DEFINITY, or Cardiac MRI can helpful in equivocal cases
TTE AP4C zoom on LV apex using echo contrast to diagnose LV thrombus. Note how contrast highlights the spaces between clot and endocardium making the diagnosis more clear.
The patient was started on warfarin with a target of 2.0-2.5 and did not have any adverse embolic phenomena. Serial echocardiography showed the thrombus slowly dissolved, though was still present at 6 months post infarction.
