血栓弹力图在初发急性心肌梗死患者中的临床应用

目的 探讨血栓弹力图(thromboelastography,TEG)监测与急性心肌梗死患者的冠状动脉病变严重程度是否相关、与住院期间主要心血管不良事件(major adverse cardiac events,MACE)是否相关.方法 选择我院初发急性心肌梗死(acute myocardial infarction,...     

冠状动脉造影正常的急性心肌梗死的临床特点和预后

【目的】探讨冠状动脉造影正常的急性心肌梗死(AMI)患者的临床特点及相关病因和预后。【方法】对432例临床诊断为AMI患者进行冠状动脉造影,冠状动脉造影正常的AMI为观察组,冠状动脉造影异常者为对照组。观察冠状动脉造影正常的AMI患者的易患因素、临床特点及预后。【结果】432例AMI患者中,22例冠状动脉造影显示正常(占5.09%),观察组年龄明显低于对照组(P<0.05),呼吸道感染、吸烟、过度悲伤、高脂饮食、过敏和免疫系统疾病较对照组明显增多(P<0.01),而高血压、高血脂及糖尿病较对照组明显降低(P<0.01),同时观察组左室功能较好,梗死后心绞痛发生率低(P<0.05)。【结论】AMI患者中约有5.09%的患者冠状动脉造影正常。此类患者既往多无高血压、糖尿病及高血脂病史,以年龄轻、呼吸道感染、吸烟、高脂饮食和过度悲伤、患有过敏和免疫系统疾病、心功能预后较好为其临床特点。     

青年人急性心肌梗死41例临床分析

【目的】分析青年人（〈45岁）急性心肌梗死（AMI）发病的临床和冠状动脉病变特点,探讨其病因及防治措施。【方法】对41例青年人AMI和同期中老年（≥50岁）AMI患者进行回顾性分析,观察危险因素及诱因、临床表现、心电图、冠状动脉病变特点等。【结果】青年组危险因素主要为吸烟、高脂血症／肥胖;多在大量吸烟、暴饮暴食、过度劳累、精神紧张等诱因后发病,胸痛典型,并发症少,预后较好。心电图检查多表现为前壁和ST段抬高心肌梗死（STEMI）;冠状动脉造影检查提示病变血管以单支病变多见,主要累及左前降支（LAD）,狭窄程度较轻,侧支循环少,很少累及主干。青年组冠脉造影正常7例（17％）亦明显高于中老年组（0例）。【结论】青年人AMI病因以动脉粥样硬化（83％）为主,各种诱因造成的冠状动脉痉挛或斑块破裂是发病的重要原因。掌握其临床特点有助于早期诊断,改变不良生活方式及减轻精神紧张有利于减少心梗的发生。     

ST Elevation in the COVID-19 Era: A Diagnostic Challenge

BackgroundSevere acute respiratory syndrome coronavirus 2 induces a marked prothrombotic state with varied clinical presentations, including acute coronary artery occlusions leading to ST-elevation myocardial infarction (STEMI). However, while STEMI on electrocardiogram (ECG) is not always associated with acute coronary occlusion, this diagnostic uncertainty should not delay cardiac catheterization.Case ReportsWe present 2 cases of patients with COVID-19 that presented with STEMI on ECG. While both patients underwent cardiac catheterization, a delay in time to intervention in the patient found to have acute coronary artery occlusion may have contributed to a poor outcome.Why Should an Emergency Physician Be Aware of This?These cases highlight the fact that while not all COVID-19 patients with STEMI on ECG will have acute coronary artery occlusions, there is continued need for prompt percutaneous coronary intervention during the severe acute respiratory syndrome coronavirus 2 pandemic.     

One-year Outcomes Following Coronary Computerized Tomographic Angiography for Evaluation of Emergency Department Patients with Potential Acute Coronary Syndrome

Objectives:  Coronary computerized tomographic angiography (CTA) has high correlation with cardiac catheterization and has been shown to be safe and cost-effective when used for rapid evaluation of low-risk chest pain patients from the emergency department (ED). The long-term outcome of patients discharged from the ED with negative coronary CTA has not been well studied.
Methods:  The authors prospectively evaluated consecutive low- to intermediate-risk patients who received coronary CTA in the ED for evaluation of a potential acute coronary syndrome (ACS). Patients with cocaine use, known cancer, and significant comorbidity reducing life expectancy and those found to have significant disease (stenosis ≥ 50% or ejection fraction < 30%) were excluded. Demographics, medical and cardiac history, labs, and electrocardiogram (ECG) results were collected. Patients were followed by telephone contact and record review for 1 year. The main outcome was 1-year cardiovascular death or nonfatal acute myocardial infarction (AMI).
Results:  Of 588 patients who received coronary CTA in the ED, 481 met study criteria. They had a mean (±SD) age of 46.1 (±8.8) years, 63% were black or African American, and 60% were female. There were 53 patients (11%) rehospitalized and 51 patients (11%) who received further diagnostic testing (stress or catheterization) over the subsequent year. There was one death (0.2%; 95% confidence interval [CI] = 0.01% to 1.15%) with unclear etiology, no AMI (0%; 95% CI = 0 to 0.76%), and no revascularization procedures (0%; 95% CI = 0 to 0.76%) during this time period.
Conclusions:  Low- to intermediate-risk patients with a Thrombosis In Myocardial Infarction (TIMI) score of 0 to 2 who present to the ED with potential ACS and have a negative coronary CTA have a very low likelihood of cardiovascular events over the ensuing year.     

Obstructive coronary artery disease in patients hospitalized for severe sepsis or septic shock with concomitant acute myocardial infarction

PurposeIt is difficult to differentiate type 1 acute myocardial infarction (AMI) with obstructive coronary artery disease (OCAD) from type 2 AMI in patients admitted for severe sepsis. The aims of this study were to assess the risk factors and prognosis of OCAD in patients admitted to the intensive care unit for severe sepsis with concomitant AMI.Materials and methodsThis is a single-center retrospective cohort study including all consecutive patients who were hospitalized for severe sepsis or septic shock between March 2006 and September 2014 and who underwent coronary angiography in the intensive care unit to identify AMI.ResultsOverall, 78 (5.5%) of 1418 patients hospitalized for severe sepsis underwent coronary angiography to identify concomitant AMI. Thirty-two patients (41%) had OCAD. Following multivariate analysis, the risk factors of OCAD were peripheral vascular disease (odds ratio [OR] = 5.7; 95% confidence interval [CI], 1.1-30.4; P = .042) and at least 2 cardiovascular risk factors (OR = 6.7; 95% CI, 1.9-23.8; P = .003). Obstructive coronary artery disease was associated with a significant mortality increase at 60 days (OR = 8.1; 95% CI, 1.9-30.2; P = .004).ConclusionsObstructive coronary artery disease is a poor prognosis factor in patients hospitalized for severe sepsis with concomitant AMI. In this setting, medical treatment should be considered for patients with peripheral vascular disease or with at least 2 cardiovascular risk factors; the need to perform coronary angiography should be considered carefully.     

急性冠脉综合征患者血清胆红素水平的相关研究

目的探讨人血清胆红素水平与急性冠脉综合征患者病变程度的关系。方法以80例行冠脉造影的患者为研究对象,其中确诊为急性冠脉综合征的67例为试验组,包括ST段抬高型心肌梗死29例,非ST段抬高型心肌梗死18例,不稳定型心绞痛20例;造影结果为阴性的非冠心病患者13例为对照组,包括X综合征患者8例,心血管神经症患者5例。所有研究对象均依据Gensini评分而分为4组,同时检测患者胆红素及各项生化指标。结果(1)急性冠脉综合征患者各组血清直接胆红素、间接胆红素与总胆红素水平均低于正常对照组(P<0.05)。随冠状动脉狭窄程度加重,胆红素水平逐渐下降。(2)血清胆红素水平与冠状动脉的狭窄程度、低密度脂蛋白、甘油三酯呈负相关(P<0.05),与高密度脂蛋白呈正相关。结论血清胆红素水平随冠状动脉狭窄程度的加重呈进行性下降,低胆红素血症可能是急性冠脉综合征发生发展的独立危险因素。     

急性心肌梗死患者血清生长分化因子15、肌钙蛋白及脑钠肽的表达及其临床意义

目的:探讨血清生长分化因子15(GDF-15)和肌钙蛋白I(cTnI)、脑钠肽(BNP)在急性心肌梗死(AMI)患者中的关系及对其近期预后的预测价值。方法:选择因胸痛(发病时间<12h)入院诊断为AMI患者122例为研究对象,冠状动脉造影正常者40例为对照组。采用ELISA法测定GDF-15及BNP浓度,采用免疫荧光定量技术测定cTnI浓度。记录患者住院和平均随访12个月期间的心血管事件(心血管死亡、心力衰竭、再发心绞痛或再发心肌梗死)的发生情况。结果:AMI组GDF-15与BNP和cTnI浓度呈正相关;发生心血管事件组GDF-15水平高于未发生心血管事件组;多变量logistic逐步回归表明GDF-15是预测近期心血管事件的危险因素(OR=0.79,95%CI:0.67～0.84,P<0.05)。结论:GDF-15与BNP和cTnI浓度呈正相关,GDF-15水平是预测近期心血管事件的有效指标之一。     

Performance and efficacy of 320-row computed tomography coronary angiography in patients presenting with acute chest pain: results from a clinical registry

The purpose of this study was to evaluate the performance of 320-row computed tomography angiography (CTA) in the identification of significant coronary artery disease (CAD) in patients presenting with acute chest pain and to examine the relation to outcome during follow-up. A total of 106 patients with acute chest pain underwent CTA to evaluate presence of CAD. Each CTA was classified as: normal, non-significant CAD (<50% luminal narrowing) and significant CAD (≥50% luminal narrowing). CTA results were compared with quantitative coronary angiography. After discharge, the following cardiovascular events were recorded: cardiac death, non-fatal infarction, and unstable angina requiring revascularization. Among the 106 patients, 23 patients (22%) had a normal CTA, 19 patients (18%) had non-significant CAD on CTA, 59 patients (55%) had significant CAD on CTA, and 5 patients (5%) had non-diagnostic image quality. In total, 16 patients (15%) were immediately discharged after normal CTA and 90 patients (85%) underwent invasive coronary angiography. Sensitivity, specificity, and positive and negative predictive values to detect significant CAD on CTA were 100, 87, 93, and 100%, respectively. During mean follow-up of 13.7?months, no cardiovascular events occurred in patients with a normal CTA examination. In patients with non-significant CAD on CTA, no cardiac death or myocardial infarctions occurred and only 1 patient underwent revascularization due to unstable angina. In patients presenting with acute chest pain, an excellent clinical performance for the non-invasive assessment of significant CAD was demonstrated using CTA. Importantly, normal or non-significant CAD on CTA predicted a low rate of adverse cardiovascular events and favorable outcome during follow-up.     

Acute myocardial infarction in twin pregnancy after assisted reproduction: A case report

BACKGROUNDAcute myocardial infarction (AMI) during pregnancy is rare, especially in twin pregnancy, and it can endanger the lives of the mother and children. Except for conventional cardiovascular risk factors, pregnancy and assisted reproduction can increase the risk of AMI during pregnancy. AMI develops secondary to different etiologies, such as coronary spasm and spontaneous coronary artery dissection.CASE SUMMARYA 33-year-old woman, with twin pregnancy in the 31^st week of gestation, presented to the hospital with intermittent chest tightness for 12 wk, aggravation for 1 wk, and chest pain for 4 h. Combined with the electrocardiogram and hypersensitive troponin results, she was diagnosed with acute ST-elevation myocardial infarction. Although the patient had no related medical history, she presented several risk factors, such as age greater than 30 years, assisted reproduction, and hyperlipidemia. After diagnosis, the patient received antiplatelet and anticoagulant treatment. Cesarean section and coronary angiography performed 7 d later showed stenosis and thrombus shadow of the right coronary artery. After receiving medication, the patient was in good condition.CONCLUSIONThis case suggests that, with the widespread use of assisted reproductive technology, more attention should be paid to perinatal healthcare, especially when chest pain occurs, to facilitate early diagnosis and intervention of AMI, and the etiology of AMI in pregnancy needs to be differentiated, especially between coronary spasm and spontaneous coronary artery dissection.     

冠状动脉造影正常的急性心肌梗死的临床特点

目的探讨冠状动脉造影正常的急性心肌梗死(AMI)患者的临床特点及相关病因和可能的发病机制。方法对419例临床诊断为AMI患者进行冠状动脉造影,冠状动脉造影正常的AMI为观察组,冠状动脉造影异常者为对照组。观察冠状动脉造影正常的AMI患者的易患因素、临床特点及可能的发病机制。结果419例AMI患者中,21例冠状动脉造影显示正常(占5.01%),观察组年龄明显低于对照组(P<0.05),吸烟、过度悲伤较对照组明显增多(P<0.05),过敏和免疫系统疾病较对照组增多(P<0.01),而高血压、高血脂及糖尿病较对照组明显降低(P<0.001),同时观察组左室功能较好且梗死部位以下壁者居多(P<0.05)。结论约有5.01%的AMI患者冠状动脉造影正常。此类患者既往多无高血压、糖尿病及高血脂病史,以年龄轻、吸烟和过度悲伤、患有过敏和免疫系统疾病、梗死部位多为下壁、心功能较好为临床特点。发病机制可能是冠状动脉病变较轻,由于冠状动脉发生痉挛或微小斑块破裂形成血栓,继而发生血栓自溶而致造影无异常。     

糖尿病酮症酸中毒并发急性ST段抬高型心肌梗死4例临床分析

目的探讨糖尿病酮症酸中毒(DKA)合并急性ST段抬高型心肌梗死(STEMI)的临床特点及救治方法。方法回顾性分析4例DKA合并急性STEMI患者临床特点及救治过程,总结救治经验。结果DKA并发急性STEMI患者女性多于男性,患者均为高血糖(>29 mmol/L),酸中毒严重(pH<7.1),酮症阳性(尿酮体+++)。4例患者中,1例为男性,3例为女性。1例女性因心源性休克死亡。2例急诊冠脉造影提示冠脉血栓形成,其中1例支架治疗,1例冠脉未见明显狭窄;1例择期造影显示冠脉内无血栓,右冠状动脉仅约30%狭窄,未予支架治疗。3例患者均顺利出院。结论尽快就医,及时补液降糖纠酸治疗,快速开通闭塞冠脉血管,可能是DKA合并急性STEMI患者救治成功的关键。     

Cross-sectional study of healthcare accessibility in rural regions among patients with acute myocardial infarction

BackgroundPatients suffering from acute myocardial infarction (AMI), mainly with ST elevation (STEMI), are at a great disadvantage in rural regions due to the lack of nearby hospitals with percutaneous coronary intervention (PCI).ObjectiveThis study aimed to analyse AMI patients’ interhospital referrals in a rural emergency department (ED), as well as the factors contributing to its system delayMethodsA cross-sectional observational study was carried out. An analysis of hospital referral was conducted as well for time intervals: from the first medical contact (FMC), first electrocardiogram (ECG), contact with the PCI hospital, ED exit, and arrival at the catheterization laboratory ward.ResultsOf the 48 eligible patients, 62.5% suffered from STEMI, and 50.0% were transferred to a PCI hospital. The median time to coronary intervention facilities was 214 min. The median time spent in the ED was 131 min, and time spent in transport was 101 min. The time interval to the first ECG was 6 to 10 min.ConclusionsInterhospital referral of AMI patients in rural settings is inconsistent and often not in compliance with international guidelines. A long system delay time is related mainly to organizational issues. STEMI patients still experience significant delays in healthcare accessibility. Nurses’ timely execution and interpretation of ECG can improve healthcare accessibility.     

急性非ST段抬高心肌梗死患者临床特点分析

目的 分析急性非ST段抬高心肌梗死(NSTEMI)患者的临床特点.方法 对211例NSTEMI和急性ST段抬高心肌梗死(STEMI)116例患者行冠状动脉造影、超声心动图检查,采集病史和症状特征进行分析.结果 与STEMI患者相比,NSTEMI患者危险因素较多,梗死后心绞痛常见,重度冠状动脉病变和三支病变多见,对心功能影响相对较小.结论 NSTEMI患者冠状动脉病变严重,梗死后心肌缺血常见,应重视对其治疗.     

Impact of the COVID-19 Pandemic on Emergency Department Use: Focus on Patients Requiring Urgent Revascularization

BackgroundThe novel coronavirus (2019-nCOV) appeared in China and precipitously extended across the globe. As always, natural disasters or infectious disease outbreaks have the potential to cause emergency department (ED) volume changes.ObjectiveWe aimed to assess the influence of the Coronavirus Disease 2019 (COVID-19) pandemic on ED visits and the impact on the handling of patients requiring urgent revascularization.MethodsWe reviewed the charts of all patients presenting to the ED of Hospital Sainte Anne (Toulon, France) from March 23 to April 5, 2020 and compared them with those of the same period in 2019. Then we analyzed complementary data on acute coronary syndrome (ST-elevation myocardial infarction [STEMI] and non-ST-elevation myocardial infarction [NSTEMI]) and neurovascular emergencies (strokes and transient ischemic attacks).ResultsThe total number of visits decreased by 47%. The number of people assessed as triage level 2 was 8% lower in 2020. There were five fewer cases of NSTEMI in 2020, but the same number of STEMI. The number of neurovascular emergencies increased (27 cases in 2019 compared with 30 in 2020). We observed a reduction in the delay between arrival at the ED and the beginning of coronary angiography for STEMI cases (27 min in 2019 and 22 min in 2020). In 2020, 7 more stroke patients were admitted.ConclusionThe COVID-19 pandemic probably dissuaded “non-critical” patients from coming to the hospital, whereas the same number of patients with a critical illness attended the ED as attended prior to the pandemic. There does not seem to have been any effect of the pandemic on patients requiring reperfusion therapy (STEMI and stroke).     

Correlation of antecedent stress myocardial perfusion imaging with the infarct related artery in ST-elevation myocardial infarction

Background While stress myocardial perfusion imaging (MPI) has strong prognostic power, it predicts the site of a subsequent acute myocardial infarction (AMI) in only 47–77% of patients. Prior studies have included small number of subjects and the interval between the stress test and the AMI has varied. The objective of the present study was to further evaluate the relationship between antecedent stress MPI and subsequent AMI. Methods We screened 600 patients admitted to our institution with acute ST-elevation MI and identified 21 patients who had a stress MPI an average of 4.8 months prior to the event. The location of perfusion defects on MPI were compared to the angiographic findings at the time of the subsequent AMI. Results Sixteen patients (76%) with AMI had defects on antecedent stress MPI while 5 patients (24%) had normal scans. Reversible or fixed perfusion defects in the territory corresponding to the site of AMI were seen in 62% of patients. All 5 patients with normal scans had multiple risk factors for coronary artery disease. Conclusion Although a normal stress MPI portends an excellent outcome, a small proportion of patients with normal scans, but with risk factors go on to develop AMI. Stress MPI has reasonable power in predicting future STEMI, but a lesser degree for the location of the future MI. Complementary imaging approaches such as coronary calcium scoring or CT angiography may be beneficial in the assessment of patients at high risk for MI.     

Emergency Medical Service Predictive Instrument–Aided Diagnosis and Treatment of Acute Coronary Syndromes and ST-segment Elevation Myocardial Infarction in the IMMEDIATE Trial

Abstract

Background. A challenge for emergency medical service (EMS) is accurate identification of acute coronary syndromes (ACS) and ST-segment elevation myocardial infarction (STEMI) for immediate treatment and transport. The electrocardiograph-based acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI) and the thrombolytic predictive instrument (TPI) have been shown to improve diagnosis and treatment in emergency departments (EDs), but their use by paramedics in the community has been less studied. Objective. To identify candidates for participation in the Immediate Myocardial Metabolic Enhancement During Initial Assessment and Treatment in Emergency Care (IMMEDIATE) Trial, we implemented EMS use of the ACI-TIPI and the TPI in out-of-hospital electrocardiographs and evaluated its impact on paramedic on-site identification of ACS and STEMI as a community-based approach to improving emergency cardiac care. Methods. Ambulances in the study municipalities were outfitted with electrocardiographs with ACI-TIPI and TPI software. Using a before–after quasi-experimental design, in Phase 1, for seven months, paramedics were provided with the ACI-TIPI/TPI continuous 0–100% predictions automatically printed on electrocardiogram (ECG) text headers to supplement their identification of ACS; in Phase 2, for 11 months, paramedics were told to identify ACS based on an ACI-TIPI cutoff probability of ACS ≥ 75% and/or TPI detection of STEMI. In Phase 3, this cutoff approach was used in seven additional municipalities. Confirmed diagnoses of ACS, acute myocardial infarction (AMI), and STEMI were made by blinded physician review for 100% of patients. Results. In Phase 1, paramedics identified 107 patients as having ACS; in Phase 2, 104. In Phase 1, 45.8% (49) of patients so identified had ACS confirmed, which increased to 76.0% (79) in Phase 2 (p < 0.001). Of those with ACS, 59.2% (29) had AMI in Phase 1 versus 84.8% (67) with AMI in Phase 2 (p < 0.01), and STEMI was confirmed in 40.8% (20) versus 68.4% (54), respectively (p < 0.01). In Phase 3, of 226 patients identified by paramedics as having ACS, 74.3% (168) had ACS confirmed, of whom 81.0% (136) had AMI and 65.5% (110) had STEMI. Among patients with ACS, the proportion who received percutaneous coronary intervention (PCI) was 30.6% (15) in Phase 1, increasing to 57.0% (45) in Phase 2 (p < 0.004) and 50.6% (85) in Phase 3, and the proportions of patients with STEMI receiving PCI rose from 75.0% (15) to 83.3% (45) (p < 0.4) and 82.7% (91). Conclusions. In a wide range of EMS systems, use of electrocardiographs with ACI-TIPI and TPI decision support using a 75% ACI-TIPI cutoff improves paramedic diagnostic performance for ACS, AMI, and STEMI and increases the proportions of patients who receive PCI.     

Rescue经皮血栓吸除术治疗急性心肌梗死血栓性病变的疗效

目的评价Rescue经皮血性吸除术对急性心肌梗死(AMI)血栓性病变的临床疗效及安全性。方法2000年11月至2002年11月用经皮血性吸除装置Rescue治疗8例急诊冠状动脉造影显示血栓性病变的AMI患者,均为男性,年龄46～75岁。重点观察Rescue血栓吸除术前后表面冠状动脉TIMI血流。结果8例AMI患者使用Rescue血栓吸除术后7例梗死相关血管(IRA)血流达TIMI3级,1例达TIMI2级,无1例出现栓塞和无复流现象。术后随访1年无主要心血管不良事件发生。结论Rescue血栓吸除术是治疗AMI血栓性病变的有效方法,可明显减少术后无复流的发生。     

Acute coronary artery stent thrombosis caused by a spasm: A case report

BACKGROUNDAcute stent thrombosis (AST) is a serious complication of percutaneous coronary intervention (PCI). The causes of AST include the use of stents of inappropriate diameters, multiple overlapping stents, or excessively long stents; incomplete stent expansion; poor stent adhesion; incomplete coverage of dissection; formation of thrombosis or intramural hematomas; vascular injury secondary to intraoperative mechanical manipulation; insufficient dose administration of postoperative antiplatelet medications; and resistance to antiplatelet drugs. Cases of AST secondary to coronary artery spasms are rare, with only a few reports in the literature.CASE SUMMARYA 55-year-old man was admitted to the hospital with a chief complaint of back pain for 2 d. He was diagnosed with coronary heart disease and acute myocardial infarction (AMI) based on electrocardiography results and creatinine kinase myocardial band, troponin I, and troponin T levels. A 2.5 mm × 33.0 mm drug-eluting stent was inserted into the occluded portion of the right coronary artery. Aspirin, clopidogrel, and atorvastatin were started. Six days later, the patient developed AST after taking a bath in the morning. Repeat coronary angiography showed occlusion of the proximal stent, and intravascular ultrasound showed severe coronary artery spasms. The patient’s AST was thought to be caused by coronary artery spasms and treated with percutaneous transluminal coronary angioplasty. Postoperatively, he was administered diltiazem to inhibit coronary artery spasms and prevent future episodes of AST. He survived and reported no discomfort at the 2-mo follow-up after the operation and initiation of drug treatment. CONCLUSIONCoronary spasms can cause both AMI and AST. For patients who exhibit coronary spasms during PCI, diltiazem administration could reduce spasms and prevent future AST.     

血管内超声显像在造影无显著狭窄病变的急性冠脉综合征中的应用

目的探讨血管内超声显像(IVUS)在冠状动脉造影无显著狭窄病变的急性冠状动脉综合征的病变检测和指导治疗中的应用价值.方法选取临床诊断急性冠状动脉综合征患者21例,4例为急性Q波性心肌梗死,3例为非Q波性心肌梗死,14例为不稳定型心绞痛,所有病例经冠状动脉造影主要冠脉未见直径狭窄>60%的病变.对靶血管(LAD 17例,RCA 3例,LCX 1例)行IVUS检查.结果 21例21处病变中14例(66.7%)为软斑块,2例(9.5%)为纤维斑块,4例(19.0%)为钙化斑块,1例(4.8%)为混合型斑块;共19例(90.5%)为偏心性斑块;13例(61.9%)正性重构,8例(38.1%)负性重构;重构指数为1.02±0.10(￣x±s).21例患者中有5例发现有斑块破裂,占23.8%;2例发现血栓,占9.5%.面积狭窄率(斑块负荷)范围从43.0%至79.1%,平均为70.0%±8.8%.病变处最小管腔直径(MLD)为(2.29±0.50) mm.IVUS测得的直径狭窄率、面积狭窄率、最小管腔面积和参照血管直径均大于定量冠状动脉造影所测得的数值(P均<0.05).根据IVUS检查结果,15例进行了血运重建术(1例冠脉搭桥术,14例支架植入术).结论在冠状动脉造影无显著狭窄病变的急性冠状动脉综合征病人中,血管内超声检查有助于明确病变的程度、性质并指导治疗方案的选择,病变的偏心性和正性重构可能是造成冠脉造影低估病变程度的主要原因.