Association of Post-operative Systolic Blood Pressure Variability With Mortality After Coronary Artery Bypass Grafting

Zhuoming Zhou; Jiantao Chen; Guangguo Fu; Xiaodong Zhuang; Jian Hou; Sida Chen; Suiqing Huang; Yuan Yue; Liqun Shang; Keke Wang; Linhua Lv; Mengya Liang; Zhongkai Wu

doi:10.3389/fcvm.2021.717073

Association of Post-operative Systolic Blood Pressure Variability With Mortality After Coronary Artery Bypass Grafting

Front Cardiovasc Med. 2021 Aug 12:8:717073. doi: 10.3389/fcvm.2021.717073. eCollection 2021.

Authors

Zhuoming Zhou^{1

2}, Jiantao Chen^{1

2}, Guangguo Fu^{1

2}, Xiaodong Zhuang^{2

3

4}, Jian Hou^{1

2}, Sida Chen^{1

2}, Suiqing Huang^{1

2}, Yuan Yue^{1

2}, Liqun Shang^{1

2}, Keke Wang⁵, Linhua Lv^{1

2}, Mengya Liang^{1

2}, Zhongkai Wu^{1

2}

Affiliations

¹ Department of Cardiac Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.
² NHC Key Laboratory of Assisted Circulation, Sun Yat-Sen University, Guangzhou, China.
³ Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.
⁴ Center for Information Technology & Statistics, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.
⁵ Department of Emergency, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.

Abstract

Background: Blood pressure variability (BPV) has long been considered a risk factor for cardiovascular events. We aimed to investigate whether post-operative systolic BPV was associated with early and late all-cause mortality in patients undergoing coronary artery bypass grafting (CABG). Methods: Clinical variables and blood pressure records within the first 24 h in the post-operative intensive care unit stay from 4,509 patients operated on between 2001 and 2012 were extracted from the Medical Information Mart for Intensive Care III (MIMIC-III) database. BPV was measured as the coefficient of the variability of systolic blood pressure, and we compared patients in the highest quartile with patients in the other three quartiles. Results: After full adjustment, patients in the highest quartile of BPV were at a higher risk of intensive care unit mortality (OR = 2.02, 95% CI: 1.11-3.69), 30-day mortality (OR = 1.92, 95% CI: 1.22-3.02), and 90-day mortality (HR = 1.64, 95% CI: 1.19-2.27). For 2,892 patients with a 4-year follow-up, the association between a higher post-operative BPV and the risk of 4-year mortality was not significant (HR = 1.17, 95% CI: 0.96-1.42). The results were supported by the comparison of survival curves and remained generally consistent in the subgroup analyses and sensitivity analyses. Conclusions: Our findings demonstrated that in patients undergoing CABG, a higher post-operative BPV was associated with a higher risk of early mortality while the association was not significant for late mortality. Post-operative BPV can support doctors in identifying patients with potential hemodynamic instability and making timely clinical decisions.

Keywords: blood pressure; coronary artery bypass grafting; intensive care; mortality; variability.