What is the risk of Cerebrovascular Accident (CVA) for aortic graft surgery?

Risk of Cerebrovascular Accident (CVA) in Aortic Graft Surgery

The risk of cerebrovascular accident (CVA) in aortic graft surgery varies by procedure type, with stroke rates ranging from 2-7% for total arch replacements and lower rates for other aortic procedures.

Risk Stratification by Procedure Type

• Composite valve graft procedures have a mortality rate of 1-5%, with stroke being one of the potential complications 1
• Total arch replacement procedures carry a 2-7% risk of stroke, with higher rates (up to 14%) for emergency operations 1
• Descending thoracic aortic repairs have a lower risk of CVA but carry a 2-4% risk of spinal cord ischemia which can lead to paralysis 1
• Thoracoabdominal repairs have a 3-10% risk of spinal cord ischemia, which is a different but significant neurological complication 1

Risk Factors for CVA During Aortic Surgery

• Aortic manipulation is a significant independent predictor of CVA, particularly in patients with extracoronary vasculopathy 2
• Severe atherosclerosis and intraluminal thrombus of the aorta increase the risk of embolic stroke during catheter and guidewire manipulation 1
• Advanced age and prolonged cardiopulmonary bypass time are independent predictors of stroke in patients undergoing aortic valve surgery after previous CABG 3
• Intentional coverage of the left subclavian artery during endovascular procedures may increase the risk of perioperative stroke 1

Endovascular vs. Open Surgical Approach

• There are no conclusive data demonstrating that endovascular approaches have a lower prevalence of neurological complications compared to open surgical repair 1
• Endovascular procedures involving the aortic arch pose significant risk to cerebral blood flow 1
• In the Talent VALOR trial, approximately 50% of thoracic endograft implants required intentional coverage of the left subclavian artery, which may increase stroke risk 1

Risk Mitigation Strategies

• Preoperative assessment of the patency of the contralateral right subclavian and vertebral arteries is recommended when left subclavian artery coverage is planned 1
• Verification of vertebral artery communication at the basilar artery by transcranial Doppler or angiography is recommended before covering the left subclavian artery 1
• Cerebrospinal fluid (CSF) pressure monitoring and drainage are important strategies to minimize the risk of paraplegia, especially when covering most of the descending thoracic aorta or in patients with previous abdominal aneurysm repair 1
• Preventive cerebrospinal fluid drainage should be considered in high-risk patients 1

Special Considerations

• Patients with previous abdominal aneurysm repairs (either open or endovascular) have a 10-12% risk of spinal cord ischemia during thoracic endovascular procedures, compared to 2% in those without previous repairs 1
• Postoperative atrial fibrillation after cardiac surgery is associated with a higher long-term risk of CVA (6.3% vs. 3.7% at 10 years) 4
• The STS risk calculator may overestimate risk for all but the highest risk patients undergoing aortic valve replacement after prior CABG 5

Mortality and Morbidity Implications

• The 30-day mortality for patients who experience a postoperative CVA is approximately 34.7% 2
• Maintaining good hemodynamic status is crucial to reduce CVA incidence in all patients 2
• For patients with Marfan syndrome, connective tissue disorders, or bicuspid aortic valves who undergo appropriate surgical repair, the long-term prognosis is excellent with an average survival of 70 years 1

Remember that risk assessment should be performed using validated tools such as the STS PROM (Society of Thoracic Surgeons Predicted Risk of Mortality), considering factors such as age, frailty, organ system compromise, and procedure-specific impediments 1.