Tractor versus Motorcycle

Fred is a real motorcycle aficionado. He has a passion for the feeling of freedom when cruising the streets of Lower Austria on his Suzuki.
At least this was the case until July 30, 2008. A tractor with a large trailer carrying seeds tipped just as Fred was coming the other way on his motorcycle. There was no time to react. The result was a head-on collision with the tractor. Fred was lucky: he hit the large rubber tires of the tractor, which catapulted him back to more than 20 meters. He landed on a field at the roadside.

The motorcycle, the ambulance, the tractor and the trailer.
(original photographs of the accident)


What was left of the motorcycle.
(original photograph of the accident)

The tractor and its trailer upside down.
(original photograph of the accident)
Barely conscious, he was brought to the nearest hospital. He survived the crash but suffered a sternal fracture, multiple bruises, and a fractured arm.
Fred did not give up riding the motorcycle, but did drive more carefully from then on.
You can't escape the past:
Almost four years later he noticed that he had trouble climbing stairs. He neglected the symptoms, but when his heart started to beat rapidly and irregularly it was time to see a doctor. The immediate diagnosis was atrial fibrillation. Fred was sent to us for cardioversion. What was his underlying problem? Here are Fred's key echo images (click on images for video):


Short-axis view. The right ventricle is enlarged, right
ventricular  function is hyperdynamic, and left ventricular
function is impaired.
Fred has a huge right ventricle with septal flattening. Those of you who watch our lectures and read our blog posts (like this one, or this one) already know how pulmonary hypertension affects the right ventricle and septal motion. But this case is different. Right ventricular function is hyperdynamic, which points to the presence of right ventricular volume overload. Essentially, there are three common causes of right ventricular volume overload:
- shunt at the atrial level (ASD),
- tricuspid regurgitation, and
- pulmonary regurgitation.
The next image will show you which of the three options is applicable in this case:

Four-chamber view; color Doppler study of the tricuspid valve
showing severe tricuspid regurgitation.
Okay. Severe tricuspid regurgitation is the cause of right ventricular volume overload. Volume overload of the right atrium (dilated right atrium), obviously, is the reason for atrial fibrillation. But there is something else that is very peculiar. Let us now focus on the tricuspid valve.

 Four-chamber view
The anterior leaflet of the tricuspid valve is flail. It has ruptured. One can see that the head of papillary muscle is detached. No wonder the patient has severe tricuspid regurgitation.

Zoom view of the tricuspid valve

Transesophageal study showing the tricuspid valve
How does this relate to the motorcycle accident? Rupture must have occurred during the blunt chest trauma Fred had experienced 4 years ago, as he has no other predisposing factors for rupture (endocarditis, pacemaker, or a history of myocardial biopsy).
Sequelae of a blunt chest trauma

Tricuspid valve rupture is the most common valvular defect after blunt chest trauma. As even severe tricuspid regurgitation can be tolerated for a rather long period of time, the diagnosis is often missed. The anterior leaflet is most commonly involved (as in our case). The flail tricuspid leaflet is not easy to detect, as in this case, especially when the image is of poor quality. Always watch out for eccentric jets, as they may point to the presence of a flail leaflet (remember, we also talked about that in our last blog post entitled “catching the right moment”?)
What next?
The treatment of choice is certainly tricuspid valve repair, which might not be easy because a simple annuloplasty ring will not be enough. Special repair techniques will have to be used.
Help needed
There is one additional finding that calls for explanation in this case: Why is left ventricular function reduced? The patient's coronaries were normal and he did not have a history of systemic or other disease that would explain this finding. I don't have a definite answer, but I do have a few possible explanations. Please post your thoughts in the comments section below. 123sonography needs your help!

In the next post I will show you a few additional findings that may be important.
yours Tommy & the 123sonography team

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