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Katz et al. Vessel Plus 2023;7:1 https://dx.doi.org/10.20517/2574-1209.2022.52 Page 5 of 16

[14]
inflammatory . Large TAAAs can compress adjacent structures, including pulmonary vessels, leading to
unilateral pulmonary edema and dyspnea. Rarely, aortopulmonary fistulas can be caused by aneurysm
erosion into lung parenchyma, potentially causing massive hemoptysis, respiratory failure, and hemorrhagic
shock [14,15] .

Cardiovascular
Coexisting cardiac disease, especially coronary artery disease, is prevalent in approximately 30% of extent I
and II patients and approximately 50% of extent III and IV patients . In our 2016 case series, 15% of
[1]
[7]
patients undergoing open TAAA repair had previously undergone coronary artery bypass grafting . Of
particular importance is preoperative assessment of any left internal mammary graft, as clamping during
repair of extent I or II aneurysms can injure the graft or occlude its takeoff from the left subclavian artery.
Moreover, aortic cross-clamping without left-heart bypass greatly increases afterload on the heart, which in
turn amplifies myocardial oxygen demand. When the coronary blood supply is not capable of sustaining
this increased demand, myocardial ischemia results. Postoperatively, coronary ischemia can be caused by
blood loss, graft or stent occlusion, or embolic events. The extent of coronary artery disease and urgency of
the TAAA or DTA will influence the choice of revascularization strategy and the timing of the repair.

Detecting coexisting cardiac disease requires a comprehensive cardiac evaluation, starting with baseline
electrocardiography, echocardiographic evaluation of ventricular and valvular function, and, if warranted, a
myocardial perfusion scan and cardiac catheterization . Patients should be risk-stratified for perioperative
[16]
[17]
cardiac complications by using predictive tools such as the Revised Cardiac Risk Index , which considers
the type of surgery and history of ischemic heart disease, heart failure, cerebrovascular disease, diabetes, and
preoperative renal failure to estimate 30-day risk for death, myocardial infarction, and cardiac arrest. In our
[18]
practice, we follow current guidelines to help guide further workup and diagnostic testing .
For patients presenting with acute dissection or rupture, anti-impulse therapy is promptly initiated with
intravenous labetalol or esmolol as first-line agents; other vasodilators (nicardipine) are administered as
needed.

Renal
Acute kidney injury (AKI) is a common complication of thoracic aortic surgery, with higher rates in extent
II repairs . Preoperative renal dysfunction, advanced age, long intraoperative renal ischemia times due
[7]
primarily to aortic clamping and renal artery disruption, and transfusion of packed red cells are known risk
[21]
factors for postoperative AKI [7,19,20] . Reported postoperative dialysis rates range from 2% to 12% . Chronic
kidney disease (CKD) considerably increases the risk for renal replacement therapy and early death .
[22]
Permanent renal failure with dialysis is associated with a significant increase in mortality, with one large
[7]
case series reporting an in-hospital mortality rate of 57% . Thus, in patients with CKD, preoperative
nephrology consultation and discussion of the potential need for renal replacement therapy is worthwhile.

Close preoperative assessment of renal function is warranted. If a patient is on dialysis that uses an
arteriovenous fistula or graft, we place a temporary dialysis catheter at the time of surgery to provide for
continuous renal replacement therapy in the postoperative period. This is done to minimize the
hemodynamic effects of premature initiation of hemodialysis during this early postoperative period, which
may induce hypotension and risk spinal cord ischemia. Similarly, a temporary dialysis catheter is routinely
placed in the operating room for patients at increased risk for needing dialysis (primarily those with
advanced CKD). A dialysis catheter placed femorally can be relocated to an alternative site as needed to
reduce the risk for postoperative infection.