Open Repair of Residual Type B Aortic Dissection Following Revised Type A Aortic Dissection Repair

A. Amundson

Purpose: Aortic dissections (AD) are an acute aortic syndrome which involve disruption of the tunica intima of the aorta, leading to a dissection plane with blood penetrating into the tunica media. Type A AD, those with entry tears in the ascending aorta, require emergent surgery. Type A hemiarch repairs control the immediate threat to life but often leave a residual Type B AD. The management of residual Type B AD strives to tackle malperfusion or aneurysmal degeneration.

Materials and Methods: A 51-year-old male with a past medical history of hypertension and hyperlipidemia presented to the emergency department with chest pain. Investigation revealed recent open repair of acute Type A AD at an outside hospital, prompting computed tomography angiography revealing a 1.6cm by 1.0cm mediastinal hematoma. An echocardiogram demonstrated tamponade physiology, necessitating urgent intervention. Redo-sternotomy, aortic valve replacement, and aorto-right axillary bypass with a 10mm Dacron graft were performed without complication. An additional residual Type B AD, in zones 1-10, measuring 4.5cm in the abdominal section was noted and medically managed. Two-year post-op surveillance revealed distal degeneration of the dissection to 6.3cm in zone 9, crossing the threshold from medical to surgical management.

Results: Open aortic repair with 24mm by 12mm bifurcated Dacron graft and open fenestration of the septum was successfully performed. Post-operative imaging showed a stable interval dissection segment which will undergo continued surveillance.

Conclusions: Aortic dissections are a life-threatening condition that requires efficient identification, prompt management and regular post-operative monitoring. The management of a residual Type B AD is an evolving field. This patient’s aneurysmal degeneration of the abdominal section required intervention to prevent rupture and death. The lack of a dissection free landing zone made endovascular repair unfavorable, prompting open repair. With ongoing surveillance strategies residual Type B AD can be successfully managed to prevent late complications.