Aortic regurgitation due to back-and-forth intimal flap movement detected by both multidetector computed tomography and transesophageal echocardiography

Abstract

A 46-year-old man with a history of hypertension, chronic kidney disease, and chronic aortic dissection classified as DeBakey type IIIB was referred to our hospital with chest and back pain. The patient underwent 64-row multidetector computed tomography (MDCT), which revealed new-onset DeBakey type II aortic dissection. The intimal flap prolapsed into left ventricle in the diastolic phase of cardiac cycle and stuck to the right coronary cusp (RCC) of the aortic valve. He also underwent transesophageal echocardiography (TEE) to assess the relationship between the intimal flap and aortic valve in detail. The intimal flap overlaid the RCC and prolapsed into the left ventricle outflow tract in the diastolic phase. These images suggested that the circumferential intimal flap stuck to the aortic valve, resulting in severe aortic regurgitation. One day after the admission, the patient underwent replacement of ascending aorta with a prosthetic graft. Intraoperative observation exhibited the intimal flap inverted to the left ventricle. MDCT could detect the flat movement, as well as TEE, in addition to the extent of aortic dissection. <Learning objective: Acute aortic regurgitation is one of the complications in aortic dissection involving the ascending aorta. The mechanisms are aortic root dilatation, asymmetry of the aortic root, and diastolic prolapse of the intimal flap into the left ventricle. Evaluation of the mechanism is beneficial for surgical procedure and TEE is a useful tool. With the advancement of MDCT, MDCT could also detect the flap movement and become a useful tool for evaluating mechanism, in addition to the extent of aortic dissection.>

Role of transesophageal echocardiography in surgical treatment of aortic dissection

“…3. Intimo-intimal intussusception: Rarely, a highly mobile intimal flap in the ascending aorta results in intimo-intimal intussusception or invagination into the aortic valve [6][7][8][9][10]. If there is a tear on the invaginated flap, regurgitation ensues (Figure 4d).…”