Select View
Apical 4-Chamber (A4C)
The apical 4-chamber view is the most important view for contrast echocardiography. It provides the best visualisation of the LV apex (the most common site for thrombus), enables biplane EF calculation, and allows assessment of all apical and mid-ventricular segments. Steep left lateral positioning is essential.
Transducer Positioning
Step-by-Step Acquisition
- 1Position patient in steep left lateral decubitus — 60–90° tilt is essential
- 2Raise left arm above head to open intercostal spaces
- 3Palpate cardiac apex — typically 5th–6th ICS, midaxillary line
- 4Place probe at apex with indicator toward patient's left (3 o'clock)
- 5Tilt probe slightly anteriorly to open the apex
- 6Activate contrast mode (low MI 0.1–0.2); reduce gain significantly
- 7Adjust depth to include full LV — do NOT foreshorten the apex
- 8Wait for complete LV opacification before acquiring cine loops
Structures Visible
Contrast-Specific Tips
LV apex is the last region to opacify — wait for complete apical filling before assessing for thrombus
Apical thrombus: avascular filling defect at apex — does NOT enhance with contrast
Apical HCM: spade-shaped cavity with apical obliteration — contrast dramatically improves diagnosis
LVNC: deep trabecular recesses fill with contrast — NC:C ratio >2.3 (systole) supports diagnosis
Takotsubo: apical ballooning with basal hyperkinesis — contrast confirms extent of apical akinesis
Biplane EF: trace endocardial border at end-diastole and end-systole — contrast improves accuracy by 15–20%
Common Pitfalls
Foreshortening — most common error. Ensure apex is at top of screen; move probe laterally if needed
Near-field artifact — high gain causes bright artifact near probe; reduce gain to avoid pseudo-thrombus
Apical dropout — signal dropout at apex can mimic thrombus; use contrast to confirm
Inadequate left lateral positioning — supine position causes LV to fall away from chest wall
Artifacts at This View
Bright artifact near probe tip mimics thrombus. Reduce gain — true thrombus persists; artifact disappears.
Signal dropout at apex due to beam angle. Contrast fills the cavity and eliminates this artifact.
Side lobes from strong reflectors (MV annulus) project into LV cavity. Contrast confirms true cavity filling.
Clinical Pearls
Contrast increases sensitivity for apical thrombus detection from ~33% to >90%
If apical thrombus is suspected on unenhanced echo, ALWAYS use contrast to confirm or exclude
Apical HCM is frequently missed on unenhanced echo — contrast is essential for diagnosis
LVNC: contrast fills deep recesses (>2.3x compacted layer in systole) — confirms diagnosis
EF measured with contrast is more reproducible and accurate than unenhanced EF