the 99th percentile谢谢？

A pproximately 17.2 million surgeries are performed annually in the US.Multiple cardiovascular risk factors such as hypertension and hyperlipidemia are present in 45% of patients aged 45 years or older undergoing noncardiac surgery, and nearly 25% have a history of atherosclerotic cardiovascular disease.The incidence of perioperative cardiovascular events is related to the risk for cardiovascular events in the individual patient before surgery. In a retrospective study of more than 10 million hospitalizations for noncardiac surgery in adults across the US, the combined rate of perioperative death, myocardial infarction, and ischemic stroke was 3.0%. Myocardial injury, defined as an elevated troponin level above the 99th percentile, occurs in up to 20% of patients after noncardiac surgery.This review summarizes evidence regarding risk assessment, testing, and optimal medical therapy to reduce perioperative cardiovascular risk prior to noncardiac surgery (Box 1).

美国每年大约有1720万例手术。在接受非心脏手术的≥45岁的患者中，45%的患者存在多种心血管危险因素（如高血压和高脂血症），近25%的患者有动脉粥样硬化性心血管疾病的病史。围术期心血管事件的发生率与每个患者在术前发生心血管事件的风险有关。在一项对全美1000多万成人非心脏手术住院的回顾性研究中，围术期死亡、心肌梗死和缺血性中风的总发生率为3.0%。心肌损伤（定义为肌钙蛋白水平升高到正常范围99%以上）在非心脏手术后发生的比例高达20%。本综述总结了有关非心脏手术前风险评估、实验室检查和降低围术期心血管风险的最佳药物治疗的证据（表1）。

the 99th percentile正常范围99%？谢谢