Case of the Month #3 – Answer
Case 3 – Answers and Discussion
The parasternal long-axis view shows a hyperdynamic, underfilled left ventricle (LV) with an unusually large right ventricular outflow tract. Though we seldom make conclusions about anything RV related in this view, this finding is immediately suspicious for severe RV dilation.
The parasternal short axis view shows increased right ventricle (RV) pressures resulting in the intraventricular septum being pushed into the LV, creating a “D” shaped septum.
The image of the IVC shows a plethoric IVC with a clot within the IVC.
Another hyperechoic clot briefly enters the IVC superiorly (screen right):
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The ultrasound images of a hyperdynamic LV, increased RV pressures and plethoric IVC with clot within the IVC are supportive of a cor pulmonale state related to an acute pulmonary embolism. Additional echo support for significant heart strain (not shown here) include relative chamber size enlargement (RV:LV ratio – best seen from the apical 4 chamber plane) and Doppler measurements, including right ventricular systolic pressure (RVSP).
In this patient, CT pulmonary angiography confirmed a large saddle embolism with extensive bilateral filling defects. This patient was admitted to the ICU, received fibrinolysis and was intubated for 24 hours. The patient made a striking recovery and was discharged home in stable condition after 2 days in the ICU.
The choice of thrombolysis for PE remains a controversial (and therefore exciting) topic.
In 2011, the American Heart Association published guidelines with recommendations on the management of massive and submassive PE. Massive PE was described as acute PE with sustained hypotension (SBP < 90mmHg) for at least 15 minutes or requiring inotropes. Submassive PE was described as acute PE without systemic hypotension but with either RV dysfunction or myocardial necrosis.
Several methods were suggested to assess for RV dysfunction, including echocardiographic evidence of RV dilation or RV systolic dysfunction. The RV is considered dilated on an apical 4-chamber view when RV diameter/LV diameter > 0.9. The apical 4-chamber view was not provided with this case, but RV dilation can be seen (but not measured) on the parasternal short axis view provided and elevated RV pressure is evident when the septum is flattened and pushed into the LV during systole (“D” shaped septum).
The literature on fibrinolytics for PE has been conflicting, however the AHA has created an algorithm for the use of fibrinolytics in PE. Fibrinolytics are suggested for massive PE when there are no contraindications, and the AHA states that fibrinolytics may be considered for submassive PE depending on the clinical judgement of the physician with the assistance of the below algorithm. With 2 large RCT’s in progress, we should have more data on the use of lytics for the submassive version of this disease to further inform our clinical judgment soon.
Algorithm from AHA Guidelines on Management of Massive and Submassive PE: