Stroke after Cardiac Surgery and its Association with Asymptomatic Carotid Disease: An Updated Systematic Review and Meta-analysis

Objectives(i) Prevalence of stroke in neurologically symptomatic/asymptomatic patients with unilateral/bilateral carotid disease (including occlusion) undergoing cardiac surgery without prophylactic carotid endarterectomy (CEA) or carotid stenting (CAS). (ii) Prevalence of stroke in asymptomatic patients with unilateral/bilateral carotid disease (excluding occlusion) who underwent isolated cardiac surgery. (iii) Prevalence of stroke in the hemisphere ipsilateral to a non-operated asymptomatic stenosis in patients with severe bilateral carotid disease undergoing a synchronous unilateral CEA + cardiac procedure.MethodsSystematic Review and meta-analysis.ResultsCardiac surgery patients with a symptomatic/asymptomatic 50–99% stenosis or occlusion incurred a 7.4% stroke risk (95%CI 4.8–9.9), increasing to 9.1% (95%CI 4.8–16) in those with 80–99% stenoses or occlusion. After excluding patients with a history of stroke/TIA and those with isolated/bilateral occlusions, the stroke risk fell to 3.8% (95%CI 2.0–4.8) in patients with asymptomatic 50–99% stenoses and 2.0% in those with 70–99% stenoses (95%CI 1.0–5.7). The prevalence of ipsilateral stroke in patients with a unilateral, asymptomatic 50–99% stenosis was 2.0% (1.0–3.8), while the risk of any stroke was only 2.9% (2%–5.7%). These risks did not increase with stenosis severity (70–99%, 80–99%). Patients with bilateral, asymptomatic 50–99% stenoses or a 50–99% stenosis + contralateral occlusion incurred a 6.5% stroke risk following cardiac surgery, while the risk of death/stroke was 9.1% (3.8%–20.6%). Patients with bilateral 80–99% stenoses undergoing a unilateral synchronous cardiac/carotid revascularisation incurred a 5.7% risk of stroke in the hemisphere ipsilateral to the non-operated, contralateral stenosis.ConclusionsThere is no compelling evidence supporting a role for prophylactic CEA/CAS in cardiac surgery patients with unilateral asymptomatic carotid disease. Prophylactic CEA/CAS might still be considered in patients with severe, bilateral asymptomatic carotid disease, but such a strategy would only benefit 1–2% of all cardiac surgery patients.