Retrosternal Deformations after Coronary Artery Bypass Surgery Using Statistical Shape Analysis

Abstract Introduction: In this study, we aimed to evaluate the anatomical deformations of the major vascular structures in the retrosternal area caused by adhesions following coronary artery bypass grafting (CABG). Methods: This single-center, retrospective study included a total of 40 patients with a previous CABG who were admitted to our emergency unit for any reason and underwent a contrast-enhanced chest computed tomography (patient group) and 40 patients without previous cardiac surgery (control group) between January 2018 and November 2019. The retrosternal area was compared between the groups using the statistical shape analysis method. The distance between the sternum and the ascending aorta and pulmonary artery was measured and anatomical deformations of the retrosternal area were examined. Results: There was a statistically significant difference in the anatomical structures of the retrosternal area between the patient and control groups (P<0.001). The distance from the midsternal line to the highest point of the pulmonary artery was statistically significantly shorter in the patient group, compared to the control group (P=0.013). The distance from the sternum to the ascending aorta was also shorter in the patient group, although it did not reach statistical significance (P>0.05). Conclusions: Our study results showed narrowing of the retrosternal area following CABG and a shorter distance from the sternum to the pulmonary artery than the ascending aorta. Based on these findings, surgeons should be cautious about possible injuries in patients requiring cardiac surgery with repeated median sternotomy.

Consequence of ischemic stroke after coronary surgery with cardiopulmonary bypass according to stroke subtypes

Abstract Introduction: The aim of this study was to determine the outcomes of patients developing ischemic stroke after coronary artery bypass grafting (CABG). Methods: From March 2012 to January 2017, 5380 consecutive patients undergoing elective coronary surgery were analyzed. Ninety-five patients who developed ischemic strokes after on-pump coronary surgery were included in the study, retrospectively. The cohort was divided into four subgroups [total anterior circulation infarction (TACI), partial anterior circulation infarction (PACI), posterior circulation infarction (POCI), and lacunar infarction (LACI)] according to the Oxfordshire Community Stroke Project (OCSP) classification. The primary endpoints were in-hospital mortality, total mortality, and survival analysis over an average of 30 months of follow-up. The secondary endpoints were the extent of disability and dependency according to modified Rankin Scale (mRS). Results: The incidence of stroke was 1.76% (n=95). The median age was 62.03±10.06 years and 68 (71.6%) patients were male. The groups were as follows: TACI (n=17, 17.9%), PACI (n=47, 49.5%), POCI (n=20, 21.1%), and LACI (n=11, 11.6%). Twenty-eight (29.5%) patients died in hospital and 34 (35.8%) deaths occurred. The overall mortality rate of the TACI group was significantly higher than that of the LACI group (64.7% vs. 27.3%, P=0.041). The mean mRS score of the TACI group was significantly higher than that of the other groups (P=0.003). Conclusion: Patients in the TACI group had higher in-hospital and cumulative mortality rates and higher mRS scores. We believe that use of the OCSP classification and the mRS may render it possible to predict the outcomes of stroke after coronary surgery.