A 45 year old woman with chronic alcoholic liver disease presents to the ED with exertional dyspnoea and is noted to have a SpO2 of 90% at rest despite having a normal chest examination and CXR. She has numerous spider naevi on her chest.
She describes dyspnoea that is improved when she lays down in bed.
An echocardiogram is performed to look for evidence of heart failure, pericardial effusion or pulmonary hypertension. This clip was taken during the echocardiogram:
Which view of the heart is this? How is it acquired?
This is an apical 3 chamber view.
This is done by finding the best apical window and from the standard 4 chamber view we rotate the probe 90 degrees counterclockwise to get a view with just the left ventricle and left atrium in plane.
What is the abnormal finding on this clip?
The left atrium and ventricle appear to be contracting normally with a reasonable ejection fraction.
The mitral valve is moving normally with no obvious pathology.
However…if you look closely there are tiny bright “bubbles” moving through the left ventricle – this is consistent with spontaneous gas within the left side of the heart.
In order to identify the possible cause of these bubbles an echo “bubble study” was performed. Agitated blood, saline and air are rapidly injected into a proximal vein as the heart is viewed in the apical 4 chamber window.
What does the video clip show?
In a normal patient the bubbles should fill the right heart then be filtered by the lungs with little or no bubbles reaching the left side of the heart.
This clip shows the right heart filling with bubbles as the agitated saline is injected. Then after approximately 3 heart beats the left side fills with bubbles also.
So what is happening to this patient?
How do those bubbles get to the left ventricle?
In order for bubbles to make it from right to left – there must be a shunt present. There are two main shunts that may occur.
- A intracardiac shunt such as a patent foramen ovale (PFO) would result in very early filling of the left ventricle within 1 or 2 heart cycles. The bubbles would be seen crossing the interatrial septum into the RA. This is not the case here.
- A pulmonary shunt occurs when there is abnormal vascular shunting of blood through the lungs. IN this case the bubbles never pass through the microcirculation of the lungs. This is typically delayed to the 3rd to 5th cycle after injection and we can see the bubbles return to the left atrium via the pulmonary veins.
What is the diagnosis?
This patient has hepatopulmonary syndrome.
This is a complex syndrome associated with portal hypertension and advanced liver disease.
Hepatopulmonary syndrome is the result of chronic inflammation and accumulation of macrophages in the lung which secrete various substances which results in angiogenesis, nitric oxide synthase induction and pulmonary vasodilation. The end result is the formation of a significant pulmonary vascular shunt.
- Nickson C. Hepatopulmonary Syndrome. LITFL
- Bansal K, Gore M, Mittal S. Hepatopulmonary Syndrome. StatPearls
- Hopkins WE, Waggoner AD, Barzilai B. Frequency and significance of intrapulmonary right-to-left shunting in end-stage hepatic disease. Am J Cardiol. 1992 Aug 15;70(4):516-9.
TOP 100 ULTRASOUND CASES
An Emergency physician based in Perth, Western Australia. Professionally my passion lies in integrating advanced diagnostic and procedural ultrasound into clinical assessment and management of the undifferentiated patient. Sharing hard fought knowledge with innovative educational techniques to ensure knowledge translation and dissemination is my goal. Family, wild coastlines, native forests, and tinkering in the shed fills the rest of my contented time. | SonoCPD | Ultrasound library | Top 100 | @thesonocave |