Carotid Artery Stenosis does not Increase the Perioperative Risk of Stroke in Patients Undergoing Aortic Non-Clamping and No-touch off-pump Surgery- A Retrospective Single-Center Analysis

Objectives: In general, higher graded (>60%) Carotid-artery-stenosis (CAS) is associated with a stroke rate up to 9% when operated without any stroke prophylaxis. CAS therefore is accepted as an independent risk factor for mortality, morbidity and stroke and is associated with coronary artery disease up to 30%.The goal of our study is to compare the stroke rate and the long-term mortality of CAS and no CAS for patients undergoing OPCAB with aortic-no-clamp- (ANC) and no-touch technique (ANTT).

Methods: A retrospective data-base analysis with patients undergoing isolated ANC (71%; 2282 patients) and ANTT (29%; 930 patients)-OPCAB between July 2009 and March 2014 was performed. Patients were divided into three groups: (I) patients with >60% CAS (n = 190) (II) patients with < 60% CAS (n = 226) (III) patients without CAS (n = 2796). Primary endpoint was the incidence of perioperative- and in hospital stroke. Secondary endpoint was the mortality rate within a five year postoperative follow-up

Results: Two (1.1%), one (0.4%), and 21 (0.8%) strokes occurred in groups I, II, and III (p = 0,770). The age- and EuroScore-adjusted odds ratio for groups I and II (reference: group III) was 1.48 (95% CI: 0.34–6.40; p = 0.597) and 0.58 (95% CI: 0.08–4.35; p = 0.596) respectively. Five-year Kaplan Meier survival estimates were in groups I, II, and III 81.7%, 75.9%, and 84.9% (p = 0.232). After adjustment for age and EuroScore, the hazard ratio of mortality for groups I and II (reference: group III) was 1.55 (95% CI: 1.00–2.39;p = 0.050) and 0.79 (95% CI: 0.47–1.32;p = 0.361).

Conclusion: Patients with CAS (group I and II) had no higher risk of perioperative stroke after ANC and ANTT-OPCAB surgery in comparison to those patients without CAS (group III). Even CAS above 60% (group I) does not increase the risk of stroke in our cohort. The mortality rate in the long term follow-up did not differ significantly between patient without CAS and CAS < 60%, but was worse for CAS > 60%. The low stroke-risk in our study may suggest that preoperative intervention in case of ACS > 60% is not necessary in patients undergoing ANC and ANT OPCAB for coronary artery disease.