Stearns Joshua D, Dávila-Román Victor G, Barzilai Benico, Thompson Richard E, Grogan Kelly L, Thomas Betsy, Hogue Charles W
Department of Anesthesiology and Critical Care Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21287, USA.
Anesth Analg. 2009 Mar;108(3):719-26. doi: 10.1213/ane.0b013e318193fe73.
Adverse cardiac events that follow cardiac surgery are an important source of perioperative morbidity and mortality for women. Troponin I provides a sensitive measure of cardiac injury, but the levels after cardiac surgery may vary between sexes. Our purpose in this study was to evaluate the prognostic value of troponin I levels for predicting cardiovascular complications in postmenopausal women undergoing cardiac surgery.
The cohort of this study were women enrolled in a previously reported clinical trial evaluating the neuroprotective potential of 17beta-estradiol in elderly women. In that study, 175 postmenopausal women not receiving estrogen replacement therapy and scheduled to undergo coronary artery bypass graft (with or without valve surgery) were prospectively randomized to receive 17beta-estradiol or placebo in a double-blind manner beginning the day before surgery and continuing for 5 days postoperatively. Serial 12-lead electrocardiograms were performed and serum troponin I concentrations were measured before surgery, after surgery on arrival in the intensive care unit, and for the first four postoperative days. The primary end-point of the present study was major adverse cardiovascular events (MACE) defined as a Q-wave myocardial infarction, low cardiac output state or death within 30 days of surgery. The diagnosis of Q-wave myocardial infarction was made independently by two physicians blinded to treatment and patient outcomes with the final diagnosis requiring consensus. Low cardiac output state was defined as cardiac index <2.0 L x min(-1) x m(-2) for >8 h regardless of treatment.
Troponin I levels on postoperative day 1 were predictive of MACE (area under the receiver operator curve = 0.862). A cutoff point for troponin I of >7.6 ng/mL (95% confidence interval, 6.4-10.8) provided the optimal sensitivity and specificity for identifying patients at risk for MACE. The negative predictive value of a troponin I level for identifying a patient with a composite cardiovascular outcome was high (96%) and the positive predictive value moderate (40%). Postoperative troponin I levels were not different between women receiving perioperative 17beta-estradiol treatment compared with placebo and the frequency of MACE was not influenced by 17beta-estradiol treatment.
In postmenopausal women, elevated troponin I levels on postoperative day 1 are predictive of MACE. Monitoring of perioperative troponin I levels might provide a means for stratifying patients at risk for adverse cardiovascular events.
心脏手术后的不良心脏事件是女性围手术期发病和死亡的重要原因。肌钙蛋白I是心脏损伤的敏感指标，但心脏手术后其水平在不同性别间可能存在差异。本研究的目的是评估肌钙蛋白I水平对预测接受心脏手术的绝经后女性心血管并发症的预后价值。
本研究队列来自一项先前报道的评估17β-雌二醇对老年女性神经保护作用的临床试验。在该研究中，175名未接受雌激素替代治疗且计划接受冠状动脉旁路移植术（有或无瓣膜手术）的绝经后女性被前瞻性随机分为两组，从手术前一天开始以双盲方式接受17β-雌二醇或安慰剂治疗，并持续至术后5天。在手术前、术后进入重症监护病房时以及术后头四天进行系列12导联心电图检查并测量血清肌钙蛋白I浓度。本研究的主要终点是主要不良心血管事件（MACE），定义为术后30天内发生的Q波心肌梗死、低心排血量状态或死亡。Q波心肌梗死的诊断由两名对治疗和患者结局不知情的医生独立做出，最终诊断需达成共识。低心排血量状态定义为无论治疗情况如何，心脏指数<2.0L·min⁻¹·m⁻²持续超过8小时。
术后第1天的肌钙蛋白I水平可预测MACE（受试者工作特征曲线下面积=0.862）。肌钙蛋白I>7.6ng/mL（95%置信区间，6.4 - 10.8）的截断点为识别有MACE风险的患者提供了最佳敏感性和特异性。肌钙蛋白I水平对识别复合心血管结局患者的阴性预测值较高（96%），阳性预测值中等（40%）。接受围手术期17β-雌二醇治疗的女性与接受安慰剂治疗的女性术后肌钙蛋白I水平无差异，且MACE的发生率不受17β-雌二醇治疗的影响。
在绝经后女性中，术后第1天肌钙蛋白I水平升高可预测MACE。围手术期监测肌钙蛋白I水平可能为对有不良心血管事件风险患者进行分层提供一种方法。
