Case 4

Previous AVR and now has aneurysm of Ascending Aorta and Arch

A 65 year old lady is referred with 7cm ascending aorta and arch aneurysm that extends to the left subclavian. She had an AVR performed for bicuspid aortic valve disease 20 years ago. In addition she has a large thyroid in front of her innominate artery. The previous AVR is functioning well, and she has no other valvular problems, and has normal coronary arteries on angiography. What would you do ?

Plan

Unless unfit for an operation conservative management is not an option.

General operative plan

She needs her root, ascending and arch replaced. Even though not mentioned in the history, post AVR ascending aortic aneurysms virtually never spare the coronary sinuses, and in bicuspid aortic valve disease the whole wall of the aorta is abnormal.

After performing the sternotomy a hemi thyroidectomy should be performed if it gets in the way of operating on the innominate artery.

Bypass setup

The bypass machine needs to be set up for circulatory arrest. 

Two arterial lines are needed: 

Option 1 - one for central  perfusion and one with a second branch in it for selective cerebral perfusion. During the period of selective cerebral perfusion the central perfusion line is inserted into the proximal descending aorta via the open arch for distal body perfusion.

Option 2 - one for femoral perfusion and one with a second branch in it for selective cerebral perfusion.

Venous return is via a two stage cannula.

Venting of the RSPV is needed.

Cardioplegia line with a branch for anterograde and retrograde cardioplegia.

One or Two pump suckers.

Cannulation options

Arterial cannulation options include femoral artery or direct cannulation of the aneurysm. Directly cannulating the aneurysm theoretically reduces the risk of CVA due to retrograde flow in the descending aorta. 

Key operative points

Dissect as much of the root, ascending and arch as is possible before giving the heparin.

Cannulate aneurysm and RA

Clamp aneurysm

Arrest using anterograde and then retrograde cardioplegia

Perform a root replacement and cool to 18^oC at the same time

Encircle innomiate, left carotid and left subclavian arteries.

Open arch

Insert anterograde perfusion cannulae into innomiate and left carotid arteries (retrograde cannulae are useful here).

Snare left subclavian artery

Insert large cannulae with balloon into proximal descending aorta via open arch and use to perfuse the lower body.

Replace arch

Join arch to root graft

Rewarm

Alternative operative strategies are numerous but include:

Total circulatory arrest

Retrograde cerebral perfusion during total circulatory arrest

Wheat procedure for the root

Root replacement, extra anatomical bypass from ascending aorta to left and right carotid arteries and then stenting the arch from root graft to proximal descending aorta.