[Risk Factors of Perioperative Cardiac Events in Elderly Patients with Coronary Heart Disease Undergoing Non-cardiac Surgery].

Objective: To identify the incidence and risk factors of perioperative major adverse cardiac events (MACE) in elderly patients with coronary heart disease (CHD) undergoing non-cardiac surgery.

Methods: We prospectively analyzed the clinical data of 360 CHD patients who aged 75 years or older undergoing elective intermediate-to high-risk surgery in five medical centers across China from January 2008 to January 2010. The clinical variables included the 12-lead ECG and Troponin I levels after surgery. The combined outcome was defined as all the perioperative MACE in hospital. The risk factors of MACE and their indexes were analyzed with univariate analysis and multivariable logistic regression in SPSS software,together with a risk scoring and stratification system established.

Results: Perioperative MACE occurred in 11.94% of elderly CHD patients undergoing non-cardiac surgery. Seven independent risk factors of perioperative MACE for this population were identified,which included angina within 6 months (P=0.001), hypertension(P=0.014), preoperative haematocrit (HCT) <40% (P=0.050), serum creatinine (Scr)>150 mmol/L (P=0.014), ejection fraction(EF) <50% (P=0.019), intraoperative hyoxemia (P=0.019), and operative time>150 min (P=0.001). The risk indexes of these factors were 4,3,3,6,4,5, and 4, respectively. The rate of perioperative MACE increased significantly as the level of risk stratification elevated.

Conclusions: Elderly CHD patients undergoing non-cardiac surgery are at high risk of perioperative MACE. Angina within 6 months,hypertension, preoperative HCT<40%, Scr>150 mmol/L, EF<50%, intraoperative hyoxemia, and operative time>150 min can increase the risk of MACE. The risk scoring and stratification system based on the risk factor index can be a valuable parameter for assessing the perioperative cardiac risk of noncardiac surgery for elderly CHD patients.