High jet velocities type II endoleak post endovascular abdominal aortic aneurysm repair (EVAR)
The most common complication of an endovascular aneurysm repair (EVAR) is the occurrence of an endoleak, defined as the persistent presence of blood flow within the thrombosed aneurysm sac despite endograft deployment.
This is a case of a 68-year old male patient, previously undergone an elective endovascular repair for a 5.5 cm abdominal aortic aneurysm (AAA). The patient was added to the local post-EVAR surveillance programme which includes regular ultrasound scans in order to diagnose the occurrence of complications. The 12 month follow up ultrasound scan reported a reduction in the original AAA sac size, from 5.5 cm to 5 cm with patent stents and the absence of endoleaks. However, the 18 month ultrasound scan identified an increase of the maximum antero- posterior diameter of 4 mm (from 5 cm to 5.4 cm), and the presence of a high jet velocity type II endoleak.
Type II endoleaks are the most common types of endoleaks, occurring in 10%–44% of patients and comprising approximately half of all endoleaks. Type II endoleak results when increased pressure within the side branches of the aorta (often the inferior mesenteric and lumbar arteries) forces blood to leak into the lower-pressure aneurysm sac. These types of endoleaks are generally considered benign; however, their natural history can be unpredictable and intervention is typically offered for persistent endoleaks associated with sac expansion or increased intrasac pressure.
TAKE HOME MESSAGE: type II endoleaks are the most common endoleaks and can be detected using colour Doppler flow and pulsed wave Doppler.