Assessment of right ventricular function in critically ill patients
VIdeo tutorial
RV assessment on PLAXAs a practical rule, you can divide the left atrium, aorta, and right ventricular outflow tract by 1/3 in a well-acquired PLAX view. If an off-axis view is acquired, then this view is less accurate. While this view if less sensitive for RV dilatation (more sensitive for RVOT dilatation), it is very specific if the RV/RVOT segment is clearly enlarged.
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RV functionThe predominant movement of the RV is longitudinal, that is from the base to the apex. Tricuspid annular systolic plane excursion (TAPSE) measures vertical displacement of the tricuspid annulus in systole. A normal vertical displacement is ~1.7 cm and greater. Notably, this is only one element of RV function and can easily be incorrect.
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RV dysfunction with normal TAPSE
Here is an example of RV dysfunction with preserved TAPSE. The lateral annulus appears to be moving well, but
Advanced topics
Ventricular interdependenceThe most challenging aspect of managing a patient with RV dysfunction is the acute patient with obstructive shock. In this case, RV dilatation prevents diastolic filling of the LV. Although the LV may be hyper-dynamic, its diastolic filling may be exceptionally low. Management of this problem is exceptionally complex and requires a multi-disciplinary approach.
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SPontaneous echo contrastIf the RV pressure is higher than the right sided filling pressure, you may see "spontaneous echo contrast" or "smoke" as a consequence of an unfavourable gradient for filling. In this condition, blood or occasionally infused saline microbubbles may swirl around the right sided circulation. This is more common in cardiac arrest and terminal PE/ severe pulmonary hypertension.
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