Surgical Risk Factors for Ischemic Stroke Following Coronary Artery Bypass Grafting. A Multi-Factor Multimodel Analysis

Sandro Gelsomino; Cecilia Tetta; Francesco Matteucci; Stefano Del Pace; Orlando Parise; Edvin Prifti; Aleksander Dokollari; Gianmarco Parise; Linda Renata Micali; Mark La Meir; Massimo Bonacchi

doi:10.3389/fcvm.2021.622480

Surgical Risk Factors for Ischemic Stroke Following Coronary Artery Bypass Grafting. A Multi-Factor Multimodel Analysis

Front Cardiovasc Med. 2021 Jul 5:8:622480. doi: 10.3389/fcvm.2021.622480. eCollection 2021.

Authors

Sandro Gelsomino^{1

2}, Cecilia Tetta¹, Francesco Matteucci^{1

3}, Stefano Del Pace³, Orlando Parise^{1

3}, Edvin Prifti⁴, Aleksander Dokollari⁵, Gianmarco Parise¹, Linda Renata Micali¹, Mark La Meir^{1

2}, Massimo Bonacchi⁶

Affiliations

¹ Cardiovascular Research Institute Maastricht - CARIM, Maastricht University Medical Centre, Maastricht, Netherlands.
² Cardiac Surgery Department, Vrije Universiteit Brussels, Brussels, Belgium.
³ Cardio-Thoraco-Vascular Department, Careggi Hospital, Florenze, Italy.
⁴ Division of Cardiac Surgery, University Hospital Center of Tirana, Tirana, Albania.
⁵ Cardiac Surgery, St. Michael's Hospital, University of Toronto, Toronto, ON, Canada.
⁶ Cardiac Surgery Unit, Department of Experimental and Clinical Medicine, University of Florence, Firenze, Italy.

Abstract

Background: Ischemic stroke after coronary artery bypass (CABG) has been often linked to aortic manipulation during surgery. Objectives: The objective of the study was to estimate the rate of postoperative ischemic stroke within 30 days from CABG by surgical risk factors alone or in combination. Methods: The multinomial propensity score for multiple treatments was used to create six models with a total of 16,255 consecutive patients undergoing isolated CABG. For each model, a different classification variable was used to stratify patients. Results: Balance achieved in all models was substantial, enabling unbiased estimation of the treatment estimand. Both off-pump techniques with (0.009; 95% CI 0.006-0.011) or without proximal anastomoses (0.005; 0.005-0.003), and surgery performed on the beating heart using cardiopulmonary bypass with (0.009; 0.006-0.011) or without proximal anastomoses (0.024; 0.021-0.029) showed a mean stroke estimate significantly lower than the other techniques. Off-pump surgery and on-pump surgery without an aortic cross-clamp yielded nearly equal incidences of stroke (0.012; 0.008-0.015 and 0.018; 0.012-0.023, respectively). Using an aortic cross-clamp significantly increased the stroke estimate (0.075; 0.061-0.088), whereas using a side-biting clamp did not (0.039; 0.033-0.044). The number of aortic touches (0.029; 0.026-0.031) and the number of proximal anastomoses (0.044; 0.035-0.047) did not significantly increase the incidence of stroke. Conclusions: Aortic cross-clamping was found to be the primary cause of post-CABG ischemic stroke. Instead, additional aortic manipulation from a side-biting clamp, on-pump surgery, multiple aortic touches, number of proximal anastomoses, and aortic cannulation were found not to increase the estimate of stroke significantly. Further research on this topic is warranted.

Keywords: aortic cannulation; aortic manipulation; coronary artery bypass—adverse effects; off-pump artery bypass and grafting; proximal aortic anastomosis; stroke; surgical technique.