Pulmonary Artery Dissection

Pulmonary artery dissection is an uncommon cause of chest pain. Pulmonary arterial hypertension (either primary or due to collagen vascular diseases, chronic obstructive pulmonary disease, congenital heart diseases, etc.) is the most common cause, but less common etiologies like Marfan syndrome (our patient), instrumentation, tuberculosis, syphilis, pregnancy, idiopathic cystic medial necrosis, and amyloidosis have also been described.

CT, MRA and echocardiography will demonstrate the intimal flap. A potential pitfall is a pseudoflap due to motion artifact from aortic and cardiac motion. A similar pseudoflap in the aorta or superior vena cava can suggest that what you're seeing is artifact. Cardiac gating (as seen in our case) would be ideal; however, this is not standard in pulmonary embolism protocol CTAs.

In this patient we see an intimal flap on a cardiac-gated CTA (pink arrow), a large left subclavian artery aneurysm (blue arrow) and a stent-graft (yellow arrow) within an aortic aneurysm in a patient with Marfan syndrome.

References

• Neimatallah MA, Hassan W, Moursi M, Al Kadhi Y. CT findings of pulmonary artery dissection. Br J Radiol. 2007 Mar;80(951):e61-3.
• Pua U, Tan CH. CT diagnosis of pulmonary artery dissection--potential pitfall of multidetector CT. Br J Radiol. 2009 Jan;82(973):82-3.
• Sehdev A, Dhoble A. Pulmonary artery dissection (PAD): A very unusual cause of chest pain. J Hosp Med. 2010 Jun 9;5(5):313-316.