摘要目的:观察心血管急危重症患者晕厥发生情况，并探讨影响其死亡的危险因素。方法:选取2018年3月至2020年3月参与中国晕厥患者前瞻性、多中心注册研究项目在南阳市第二人民医院急诊科就诊或住院治疗925例急性心力衰竭（心衰）、急性心肌梗死、肺栓塞、心律失常、主动脉夹层破裂患者为研究对象。记录患者就诊期间晕厥发生情况和病死率，以是否伴发晕厥将患者分为晕厥组和未晕厥组，分析并比较不同心血管急危重症男性与女性患者晕厥发生率，以及是否发生晕厥两组心血管急危重症患者年龄及病死率的差异；采用多因素Logistic回归分析影响患者死亡的危险因素；并绘制受试者工作特征曲线（ROC曲线），评价危险因素对患者预后的预测价值。结果:5种心血管急危重症患者中晕厥发生率由高到低依次为：急性心肌梗死3.03%（28/925）、心律失常2.70%（25/925）、肺栓塞1.51%（14/925）、主动脉夹层破裂1.41%（13/925）、急性心衰0.65%（6/925），差异均有统计学意义（ χ2＝10.765， P＝0.010）。男性与女性肺栓塞、主动脉夹层破裂、急性心肌梗死、心律失常、急性心衰患者晕厥发生率比较差异均无统计学意义。晕厥组主动脉夹层破裂、急性心肌梗死、心律失常患者的年龄明显大于未晕厥组〔主动脉夹层破裂（岁）：66.29±15.64比57.63±14.23，急性心肌梗死（岁）：69.55±15.13比62.10±15.75，心律失常（岁）：70.48±14.93比60.29±16.31，均 P<0.05〕。晕厥组肺栓塞、主动脉夹层破裂、急性心肌梗死、心律失常、急性心衰患者的病死率明显高于未晕厥组〔肺栓塞：5.81% （5/86）比0.95%（8/839），主动脉夹层破裂：4.65%（4/86）比0.60% （5/839），急性心肌梗死：4.65% （4/86）比1.19% （10/839），心律失常：2.33% （2/86）比0.95% （8/839），急性心衰：2.33% （2/86）比0.60% （5/839），均 P<0.05〕。多因素Logistic回归分析显示，年龄〔优势比（ OR）＝2.158，95%可信区间（95% CI）为0.921～4.785， P＝0.000〕、肺栓塞（ OR＝15.391，95% CI为8.904～27.314， P＝0.001）、主动脉夹层破裂（ OR＝13.079，95% CI为6.237～25.509， P＝0.000）、急性心肌梗死（ OR＝18.826，95% CI为10.420～32.921， P＝0.000）、晕厥（ OR＝4.940，95% CI为1.764～9.287， P＝0.000）是影响心血管急危重症患者预后的危险因素。ROC曲线分析显示，晕厥对患者28 d预后有一定预测价值〔ROC曲线下面积（AUC）＝0.760， P＝0.000〕，当其截断值为4.12时，敏感度为88.51%，特异度为78.05%，阳性预测值为81.31%，阴性预测值为84.27%。 结论:晕厥是影响心血管急危重症患者死亡的独立危险因素；对于晕厥为主诉就诊的患者应快速鉴别诊断急危重症类型，评估猝死风险。

abstractsObjective:To observe the incidence of syncope in patients with acute and critical cardiovascular diseases and to explore the risk factors of death.Methods:925 cases of acute heart failure, acute myocardial infarction, pulmonary embolism, arrhythmia and aortic dissection rupture who participated in Prospective, Multi-CenterRegistered Research Project for Chinese Syncope Patients from March 2018 to March 2020, admitted to the department of emergency of Nanyang Second General Hospital were selected as the research objects. The incidence and mortality of syncope were recorded, and the patients were divided into syncope group and non-syncope group according to whether they were accompanied by syncope or not. The incidence of syncope in male and female patients with different cardiovascular critical diseases, the age and mortality of cardiovascular critical patients with syncope or not were analyzed and compared. Multivariate Logistic regression analysis was used to analyze the risk factors of death, and receiver operating characteristic curve (ROC curve) was drawn to evaluate the predictive value of risk factors on the prognosis of patients.Results:The incidence of syncope in 5 kinds of cardiovascular critical patients from high to low was: acute myocardial infarction 3.03% (28/925), arrhythmia 2.70% (25/925), pulmonary embolism 1.51% (14/925), aortic dissection rupture 1.41% (13/925), acute heart failure 0.65% (6/925), with statistically significant differences ( χ2 = 10.765, P = 0.010). There was no significant difference in the incidence of syncope between male and female patients with pulmonary embolism, aortic dissection rupture, acute myocardial infarction, arrhythmia and acute heart failure. The age of patients with aortic dissection rupture, acute myocardial infarction and arrhythmia in syncope group were significantly higher than those in non-syncope group [aortic dissection rupture (years old): 66.29±15.64 vs. 57.63±14.23, acute myocardial infarction (years old): 69.55±15.13 vs. 62.10±15.75, arrhythmia (years old): 70.48±14.93 vs. 60.29±16.31, all P < 0.05]. The mortality of patients with pulmonary embolism, aortic dissection rupture, acute myocardial infarction, arrhythmia, acute heart failure in syncope group were significantly higher than those in non-syncope group [pulmonary embolism: 5.81% (5/86) vs. 0.95% (8/839), aortic dissection rupture: 4.65% (4/86) vs. 0.60% (5/839), acute myocardial infarction: 4.65% (4/86) vs. 1.19% (10/839), arrhythmia: 2.33% (2/86) vs. 0.95% (8/839), acute heart failure: 2.33% (2/86) vs. 0.60% (5/839), all P < 0.05]. Multivariate Logistic regression analysis showed that age [odds ratio ( OR) = 2.158, 95% confidence interval (95% CI) was 0.921-4.785, P = 0.000], pulmonary embolism ( OR = 15.391, 95% CI was 8.904-27.314, P = 0.001), aortic dissection rupture ( OR = 13.079, 95% CI was 6.237-25.509, P = 0.000), acute myocardial infarction ( OR = 18.826, 95% CI was 10.420-32.921, P = 0.000), syncope ( OR = 4.940, 95% CI was 1.764-9.287, P = 0.000) were risk factors for the prognosis of patients with acute and critical cardiovascular diseases. ROC curve analysis showed that syncope had a certain predictive value for 28-day prognosis of patients [the area under the ROC curve (AUC) = 0.760, P = 0.000], when the cut-off value was 4.12, the sensitivity was 88.51%, the specificity was 78.05%, the positive predictive value was 81.31%, and the negative predictive value was 84.27%. Conclusions:Syncope is an independent risk factor of death in patients with acute and critical cardiovascular diseases. For patients with syncope as the chief complaint, we should quickly identify the types of acute and critical diseases and assess the risk of sudden death.