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Cardiac Imaging for Assessment of Left Ventricular Thrombus
Figure 2: Improved Detection of Intracavitary Left Ventricular Thrombus by Contrast Echocardiography
A. Non-contrast B. Contrast
echocardiography echocardiography
In this representative example, non-contrast echocardiography (A) was interpreted as negative for left ventricular thrombus, with apical findings attributed to prominent acoustic shadowing.
Contrast echocardiography (B), shown in corresponding four-chamber orientation, demonstrated an apical thrombus (arrow). Note the improved cavity opacification and endocardial border
definition provided by use of sonographic contrast.
in a study by Thanigaraj et al., use of sonographic contrast yielded a 90% diagnosis.
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Recent product safety considerations have prompted the US
reduction in the number of echoes interpreted as non-diagnostic for LV Food and Drug Administration (FDA) to issue a boxed label warning that
thrombus.
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The clinical utility of contrast echo was also demonstrated by includes revised contraindications to the use of perflutren-containing
Kurt et al., who studied 632 consecutive patients with technically difficult echo contrast (Definity).
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Use of this contrast agent is prohibited for
non-contrast echoes.
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Compared with non-contrast echo, contrast echo patients with known or suspected right-to-left, bi-directional, or
reduced the number of uninterpretable (11.7 to 0.3%) and technically transient right-to-left cardiac shunts, as well as for patients with
difficult studies (86.7 to 9.8%; both p<0.0001). Contrast echo also yielded hypersensitivity to perflutren contrast agents. Additionally, for patients
a greater than two-fold increase in patients with definite thrombus (eight with pulmonary hypertension or unstable cardiopulmonary conditions,
versus three), while markedly reducing the number of patients with manufacturer guidelines recommend that monitoring of vital signs,
suspected but indefinite thrombus (35 versus one; p<0.0001). electrocardiography (ECG), and cutaneous oxygen saturation be
performed during and for at least 30 minutes following administration,
The diagnostic benefits of contrast echo have been linked to with resuscitation and trained personnel readily available.
improvements in clinical care. For example, among the cohort studied
by Kurt et al.,
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contrast echo use resulted in avoidance of additional While it is important to recognize that rare but serious cardiopulmonary
diagnostic procedures in 32.8% of patients and alteration in therapeutic reactions (including fatalities) have occurred during or following
management in 10.4%, with a total impact (procedures avoided, change administration of perflutren-containing microsphere contrast, multiple
in therapy) in 35.6% of patients. In this study, cost–benefit analysis outcomes studies have demonstrated that adverse events are very
demonstrated significant cost savings ($122/patient) resulting from uncommon. In a study of 18,671 hospitalized patients who underwent
echo contrast use. clinically requested echo, Kusnetzky et al. reported no difference in
acute mortality (24 hours post-echo) between patients who received
Consensus guidelines currently recommend that echo contrast be echo contrast (n=6,196) and those who underwent non-contrast echo
utilized when non-enhanced images are sub-optimal for definitive alone (n=12,475).
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Both the contrast and non-contrast groups
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