心脏磁共振及实验室检查联合评估心肌缺血

目的探讨心脏磁共振(cardiac magnetic resonance imaging,CMR)及实验室检查指标在评估心肌缺血中的临床价值。材料与方法 7只巴马小型猪成功构建心肌缺血模型,分别于术前、术后2 h、12 h、24 h、48 h、72 h、1周、2周、3周、4周检测心肌酶谱、肌钙蛋白、肌红蛋白等实验室检查指标,并于上述各时段行CMR检查,最终行病理检查。结果巴马猪术后2 h肌钙蛋白及肌红蛋白即明显升高,分别为[(0.005±0.002)、(0.338±0.768) ng/ml,P<0.05],72 h内诸心肌损伤标志物变化显著(均P<0.05),提示心肌损伤,1周后趋于平稳;CMR示缺血早期T2WI黑血序列显示心肌水肿,即危险心肌,电影(cine)序列出现局部室壁运动异常,首过灌注术后2 h即出现灌注减低或缺损,术后24 h部分心肌节段出现延迟强化,透壁程度随着缺血时间的延长,不断增加,最终经病理证实心肌坏死、纤维化。4周CMR所测心功能指标较术前显著降低(左室射血分数%:分别为62.71±8.33、45.97±6.37,P<0.05)。结论心肌酶谱及肌钙蛋白、肌红蛋白对心肌损伤有提示意义,CMR可确切地显示心肌缺血微观组织学变化,联合评估可为急性冠脉综合症提供详细的诊断信息并指导治疗。     

心肌梗死模型家猪存活心肌的磁共振延迟成像评价

背景:心脏磁共振延迟成像被认为是极有前景的无创性判断心肌存活状态的影像检查手段。目前常用的对比剂Gd-DTPA存在过高或过低评价存活心肌和不可逆性梗死心肌,而坏死亲和性对比剂ECIII-600可以准确地反映坏死心肌的面积。目的:对比冠脉内注射坏死亲和性对比剂在猪再灌注急性心肌梗死存活心肌诊断中的应用价值。方法:三四个月龄普通家猪12头,建立急性再灌注心肌梗死动物模型,分别冠脉内注射0.1mmol/kgGd-DTPA或0.005mmol/kgECIII-600。胸导R波触发心电门控,T1加权FAST序列,短轴面延迟强化扫描成像。扫描结束后沿短轴面将心脏切成6mm断面行氯化三苯基四氮唑染色和光镜检查。比较相应层面的MRI延迟强化区和氯化三苯基四氮唑染色所示梗死区的关系。结果与结论:注射Gd-DTPA的延迟成像10min时强化区面积与氯化三苯基四氮唑染色相比过高估计梗死心肌面积约21%,30min时强化区面积与氯化三苯基四氮唑染色结果一致,之后则过低估计坏死心肌的面积;注射ECIII-600的延迟磁共振成像在坏死区显示强烈而持续的对比增强,强化区面积与氯化三苯基四氮唑染色所示心肌梗死面积一致。说明ECIII-600增强磁共振延迟成像可以准确反映急性心肌梗死面积。Gd-DTPA评价心肌梗死面积不稳定,观察时间窗短,心脏磁共振成像应在对比剂注射后1h以内完成。     

心肌梗死模型家猪存活心肌的磁共振延迟成像评价

背景：心脏磁共振延迟成像被认为是极有前景的无创性判断心肌存活状态的影像检查手段。目前常用的对比剂Gd-DTPA存在过高或过低评价存活心肌和不可逆性梗死心肌,而坏死亲和性对比剂ECIII-600可以准确地反映坏死心肌的面积。目的：对比冠脉内注射坏死亲和性对比剂在猪再灌注急性心肌梗死存活心肌诊断中的应用价值。方法：三四个月龄普通家猪12头,建立急性再灌注心肌梗死动物模型,分别冠脉内注射0.1mmol/kgGd-DTPA或0.005mmol/kgECIII-600。胸导R波触发心电门控,T1加权FAST序列,短轴面延迟强化扫描成像。扫描结束后沿短轴面将心脏切成6mm断面行氯化三苯基四氮唑染色和光镜检查。比较相应层面的MRI延迟强化区和氯化三苯基四氮唑染色所示梗死区的关系。结果与结论：注射Gd-DTPA的延迟成像10min时强化区面积与氯化三苯基四氮唑染色相比过高估计梗死心肌面积约21%,30min时强化区面积与氯化三苯基四氮唑染色结果一致,之后则过低估计坏死心肌的面积;注射ECIII-600的延迟磁共振成像在坏死区显示强烈而持续的对比增强,强化区面积与氯化三苯基四氮唑染色所示心肌梗死面积一致。说明ECIII-600增强磁共振延迟成像可以准确反映急性心肌梗死面积。Gd-DTPA评价心肌梗死面积不稳定,观察时间窗短,心脏磁共振成像应在对比剂注射后1h以内完成。     

心脏磁共振延迟强化对心肌病心功能的诊断价值分析

目的:探讨心脏磁共振延迟强化对心肌病心功能的诊断价值.方法:选取2019年6月—2020年6月在泰州市人民医院收治的20例原发性扩张型心肌病患者,将其作为观察组,选择同期基础心律为窦性心律的20名健康体检者作为对照组.两组均进行心脏磁共振延迟强化检查,比较两组左心功能相关参数、心肌组织特征性追踪参数,观察心肌磁共振延迟...     

MRI心肌灌注及延迟增强对心肌梗死诊断价值的初步研究

目的评估MRI心肌灌注及延迟增强对心肌梗塞的诊断价值。方法52例疑诊心肌梗塞病例进行心脏MRI检查,男性41例,女性11例;平均年龄544Y,年龄范围：23-83岁。所有病例先后行FIESTA、心肌首过灌注及心肌延迟扫描检查。结果20例患者表现为首过灌注出现充盈缺损,可见延迟增强;1例患者出现首过充盈缺损,无延迟强化;31例既无首过充盈缺损,也无延迟强化。MRI诊断心肌梗塞的敏感性为90％,特异性为93．75％,准确性为92．31％。结论MRI首过灌注及延迟增强扫描对心肌梗塞的诊断具有较高的敏感性和特异性。     

心脏磁共振成像预测酒精性心肌病心力衰竭患者心脏不良事件

目的 探讨心脏磁共振（CMR）心肌对比剂延迟强化（LGE）对酒精性心肌病（ACM）心力衰竭患者心脏不良事件的预测能力。方法 纳入临床诊断为ACM并出现心力衰竭症状的患者58例,对所有患者行CMR,根据是否出现LGE将患者分为LGE（+）组和LGE（-）组。对所有患者进行随访,随访终点定义为发生心脏不良事件,对两组患者随访期间出现的心脏不良事件进行生存分析;将LGE、左心室舒张末期容积、左心室收缩末期容积、左心室射血分数、左心室心肌质量指数、心力衰竭出现时间、饮酒时间纳入多因素Cox比例风险模型,分析心脏不良事件的预测因子。结果 LGE（+）组22例,LGE（-）组36例,共10例发生心脏不良事件,LGE（+）组发生率[31.82%(7/22)]显著高于LGE（-）组[8.33%(3/36),P=0.02]。LGE是心脏不良事件的强预测因子（风险比值：5.74, P=0.02）。结论 CMR心肌LGE是出现心力衰竭症状的ACM患者不良心脏事件的强预测因子。     

心脏磁共振成像评价缺血性心力衰竭心肌纤维化研究进展及应用

心肌纤维化(MF)是缺血性心肌病发展至心力衰竭的重要中间环节。目前,检测MF存在较大困难,心肌活检虽然是检测MF的金标准,但精确度较低,并有一定致残、致死风险。心脏MR(如LGE、T1 mapping及近期出现的T1ρ技术)可无创量化评价MF,为临床评估和干预MF提供重要技术支持。本文对心脏MR技术在缺血性心力衰竭MF中的研究进展及应用进行综述。     

3.0T磁共振延迟强化技术检测存活心肌评估CTO-PCI术后心功能恢复情况

目的 探讨利用3.0T磁共振电影成像及心肌钆延迟强化(LGE)技术检测存活心肌,评估冠状动脉慢性完全闭塞(CTO)行经皮冠状动脉介入术(PCI)患者术后心功能恢复情况.方法 连续收集2017年12月至2019年12月就诊的CTO患者32例,所有患者在PCI术前及术后6个月行3.0T心脏磁共振检查,评估心脏结构、功能、心...     

心脏磁共振成像技术对OSAHS患者心脏的研究

目的利用心脏磁共振成像技术研究阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea-hypopnea syndrome,OSAHS)患者左心功能及心肌的变化,并对心肌组织进行量化分析。材料与方法选择符合2011年修订版OSAHS诊断标准,且经多导睡眠图(polysomnography,PSG)监测后诊断为OSAHS的男性患者24例,年龄40~60岁,及正常成年男性健康志愿者25名,年龄40~60岁,进行心脏磁共振基于梯度回波的多时相电影序列扫描、look-locker反转恢复(modified look-locker inversion recovery,MOLLI)序列对比剂注射前T1mapping扫描、基于T2平衡稳态自由进动序列(steady-state free-precession,SSFP)的T2 mapping扫描、T1 scout序列扫描、MOLLI序列对比剂注射后T1mapping扫描。获得左心功能参数左心室射血分数(left ventricular ejection fractions,LVEF)、左室舒张末期容积(left ventricular end diastolic volume,LVEDV)、收缩末期容积(left ventricular end systolic volume,LVESV)、每搏量(stroke volume,SV)、心输出量(cardiac output,CO)、心脏指数(cardiac index,CI)、左室心肌质量(left ventricular mass,LVM)、左室心肌T1值、T2值及细胞外体积分数(extracellular volume fractio,ECV)值。结果(1)心功能相关参数:OSAHS组LVEF、LVEDV及LVSV低于正常对照组,LVESV及LVM高于正常对照组,差异有统计学意义(P<0.05);收缩末期容积、每搏量、心输出量OSAHS组与正常对照组差异无统计学意义(P>0.05);(2)组织学参数:中间段T2值、心尖段T2值及左室心肌平均T2值OSAHS组高于对照组,差异有统计学意义(P<0.05);各段心肌及左室平均增强前T1值及ECV值OSAHS组高于对照组,但差异无统计学意义(P>0.05)。结论(1)心脏磁共振成像技术可以有效评估OSAHS患者心脏结构功能及心肌的早期改变,具有重要临床应用价值;(2)OSAHS患者的左心收缩及舒张功能均有不同程度的减低,心肌质量增加;(3)OSAHS患者左室心肌存在不同程度的心肌水肿和炎性改变。     

心脏磁共振特征追踪技术定量评价COPD左心室功能异常的研究

目的 利用心脏磁共振特征追踪（cardiovascular magnetic resonance feature tracking, CMR-FT）技术定量评价慢性阻塞性肺疾病（chronic obstructive pulmonary disease, COPD）患者左心室整体及各节段亚临床期心肌功能障碍。材料与方法 回顾性分析我院2021年10月至2023年2月符合纳入及排除标准的COPD患者病例47例（COPD组）,其中男25例,女22例,年龄（47.26±4.66）岁;28例COPD患者冠脉未见明显异常,19例COPD患者合并冠脉轻度狭窄（狭窄率<50%）。同时纳入年龄、性别及吸烟习惯相匹配的正常对照组30例,男17例,女13例,年龄（47.47±4.42）岁。所有纳入者均行3.0 T心脏磁共振（cardiovascular magnetic resonance, CMR）检查,分析COPD组与正常对照组左心室常规心功能、整体及节段心肌各方向（径向、周向及纵向）峰值应变（peak strain, PS）间的差异。因COPD患者多合并心血管疾病,本研究针对COPD冠脉正常和...     

Diagnostic value of routine clinical parameters in acute myocardial infarction: a comparison to delayed contrast enhanced magnetic resonance imaging

Aims: Contrast enhanced magnetic resonance imaging (ceMRI) has been shown to reliably identify irreversible myocardial injury. The aim of this study was to compare the findings on ceMRI with routine clinical markers of myocardial injury in patients with acute myocardial infarction (MI). Methods and results: Twenty-four patients with acute MI were investigated at 1.5 T. The global myocardial function was analysed with a standard cine MR protocol and a stack of short axis slices encompassing the entire left ventricle. Corresponding short axis slices were acquired for delayed ceMRI 15–20 min after the administration of 0.2 mmol gadolinium–DTPA/kg body weight. Mass of hyperenhancement and peak creatine kinase release (peak CK) was determined for each patient. The presenting 12-lead ECG was analysed for ST-elevation on admission and later development of Q-waves. Mass of hyperenhancement correlated moderately well to peak CK (r = 0.65, p < 0.01) and endsystolic volume index (r = 0.55, p < 0.01). Mass of hyperenhancement was inversely correlated to ejection fraction (r = –0.50, p = 0.02). Neither the presence of ST elevation on the admission ECG nor the later development of Q-waves did relate to the transmural extent of hyperenhancement and to the mass of hyperenhancement. Conclusion: Mass of hyperenhancement significantly correlates to global myocardial function and to peak CK. However, there is no relationship between the findings in ceMRI and 12-lead ECG abnormalities on admission suggesting an advantage of ceMRI in defining transmural extent and depicting small areas of necrosis.     

Contrast-enhanced magnetic resonance imaging reveals early decrease of transmural extent of reperfused acute myocardial infarction

In patients with myocardial infarction infarct size and transmural extent are of high prognostic value for clinical outcome and recovery of contractile function of the affected myocardium either spontaneously or after revascularisation. Delayed contrast-enhancement magnetic resonance imaging (DCE-MRI) is a non-invasive imaging technique of high accuracy for determination of myocardial infarct size and transmural extent. As decisions whether revascularisation procedures are promising in patients with coronary artery disease are increasingly based on the transmural infarct extent assessed by DCE-MRI we sought to examine whether the timing of MRI after acute myocardial infarction would influence the transmural extent. We performed DCE-imaging on a clinical 1.5 T scanner in patients at day-1 and day-7 after reperfused STEMI. We assessed the total number of segments displaying DCE as well as differentiated by the transmural infarct extent. The total number of affected segments as well as the number of segments with only subendocardial DCE did not change between day-1 and day-7. In contrast, we observed a significant decrease of the number of segments with DCE of ≥75% transmurality and a significant increase of segments with DCE grade III (51%–75% transmurality). We conclude that the transmural infarct extent is not stable over the first days after STEMI which should be taken into account when assessing viability in clinical and research settings. C. Merten and H. Steen contributed equally     

MR心肌延迟增强扫描在常见非缺血性心脏病中初步应用

目的研究常见非缺血性心脏病患者心肌病变的磁共振心肌延迟强化的影像学特征。方法回顾性分析25例非缺血性心脏病患者的磁共振心肌延迟强化特点及相应临床表现。结果 25例患者中9例患者心肌病变未出现延迟强化。6例为病毒性心肌炎,4例出现左室后壁、下壁心外膜下心肌可见斑片状延迟强化,1例室间隔部出现散在线状强化;6例为肥厚性心肌病,4例出现室间隔及左室壁出现延迟强化,表现为片状强化;12例为扩张性心肌病,4例在左心室间隔壁、侧壁可见线样强化,左室后下壁、前间隔壁各1例可见小片状强化,以心肌中层及外膜下心肌为主。1例为致心律失常型右室心肌病,延迟强化提示右室下壁及前壁可见片状强化。结论非缺血性心脏病患者心肌病变的磁共振心肌延迟强化具有一定特征,鉴别非缺血性心脏病的病因有赖于密切结合临床病史。     

磁共振多序列诊断评价急性心肌梗死的应用进展

磁共振心血管检查技术为深入了解心脏结构和功能提供了无创的方法,具有较高诊断准确性,并且无电离辐射。灌注增强后的延迟显像技术能够对心肌梗死提供有价值的诊断和预后信息,但是对于心肌梗死的程度以及心肌弥漫性改变无法准确地评价。T1 mapping技术是一种能够定量评估心肌局限及弥漫性病变的新技术,其能定量地评估心肌梗死的程度及心肌水肿的范围,具有良好的诊断及预后价值,在临床实践中有更好的应用前景。     

Cardiac magnetic resonance simultaneously evaluates Leriche syndrome and prior inferior myocardial infarction

A woman with ECG findings suspicious of ischemic heart disease was referred for coronary angiography, but this was impossible via the left or right iliac arteries because of total occlusion. Cardiovascular magnetic resonance (CMR) was performed to assess the anatomy of the abdominal aorta, cardiac function, and myocardial viability in a single study. Contrast-enhanced magnetic resonance angiography (CE-MRA) revealed Leriche syndrome resulting from occlusion of the infrarenal aorta and common iliac arteries. Delayed contrast enhancement indicated full thickness nonviable myocardial infarction. Coronary angiography via the right radial artery revealed proximal occlusion of the right coronary artery. This is the first case that illustrates the value of CMR as a time-saving non-invasive imaging technique with the ability to do in a single study what might otherwise take two studies.     

Myocardial SPECT perfusion defect size compared to infarct size by delayed gadolinium-enhanced magnetic resonance imaging in patients with acute or chronic infarction

BACKGROUND: Single photon emission computed tomography (SPECT) perfusion imaging has been considered a reference method for non-invasive estimation of infarct size in man. Recently, delayed gadolinium-enhanced magnetic resonance imaging (DE-MRI) has evolved as an accurate tool to quantify infarct size. Therefore, the present study was designed to compare perfusion defect size by SPECT to hyperenhanced volume by DE-MRI. METHODS: DE-MRI was performed in 30 patients. Fourteen were patients with revascularized first-time acute infarctions, eight revascularized chronic infarctions, and eight clinically referred non-revascularized patients. SPECT was performed in the same patients and analysed by a commercial package. RESULTS: The hypoperfused volume by SPECT was larger than the hyperenhanced volume by DE-MRI by 8 +/- 8 ml (6% +/- 5 percentage points), 10 +/- 18 ml (6% +/- 11 percentage points), and 26 +/- 30 ml (12% +/- 10 percentage points) in the acute, chronic and clinical populations, respectively. Left ventricle wall volume was smaller by SPECT in all settings. CONCLUSION: The SPECT perfusion defect size was comparable with but generally slightly larger than the hyperenhanced volume by DE-MRI in both absolute and relative terms in patients with acute and chronic infarction. The results may be related to systematic differences between modalities but could also be influenced by biological phenomena such as wall thinning or hypoperfused but viable myocardium.     

Assessment of resting perfusion defects in patients with acute myocardial infarction: comparison of myocardial contrast echocardiography, combined first-pass/delayed contrast-enhanced magnetic resonance imaging and 99mTC-sestamibi SPECT

Background Information on the accuracy of both magnetic resonance imaging (MRI) and myocardial contrast echocardiography (MCE) for the identification of perfusion defects in patients with acute myocardial infarction is limited. We evaluated the accuracy of MRI and MCE, using Single Photon Emission Computed Tomography (SPECT) imaging as reference technique.Methods Fourteen consecutive patients underwent MCE, MRI and ^99mTc-MIBI SPECT after acute myocardial infarction to assess myocardial perfusion. MCE was performed by Harmonic Power Angio Mode, with end-systolic triggering 1:4, using i.v. injection of Levovist^®. First-pass and delayed enhancement MRI was obtained after i.v administration of Gadolinium-DTPA. At MCE, homogeneous perfusion was considered as normal and absent or “patchy” perfusion as abnormal. At MRI, homogenous contrast enhancement was defined as normal whereas hypoenhancement at first-pass followed by hyperenhancement or persisting hypoenhancement in delayed images was defined as abnormal.Results At MCE 153 (68%) of segments were suitable for analysis compared to 220 (98%) segments at MRI (p<0.001). Sensitivity, specificity and accuracy of MCE for segmental perfusion defects in these 153 segments were 83, 73 and 77%, respectively. Sensitivity, specificity and accuracy of MRI were 63, 82, and 77%, respectively. MCE and MRI showed a moderate agreement with SPECT (k: 0.52 and 0.46, respectively). The agreement between MCE and MRI was better (k: 0.67) that the one of each technique with SPECT.Conclusion MCE and MRI may be clinically useful in the assessment of perfusion defects in patients with acute myocardial infarction, even thought MCE imaging may be difficult to obtain in a considerable proportion of segments when the Intermittent Harmonic Angio Mode is used.     

乳腺磁共振背景实质强化的研究进展

乳腺癌作为女性最常见的恶性肿瘤,其发病率及死亡率都较高,且不同分子亚型乳腺癌生物学表现及临床治疗、预后各不相同,寻找乳腺癌针对性和个性化诊断及治疗的影像学标记物是目前研究的热点.乳腺背景实质强化(background parenchymal enhancement,BPE)是正常纤维腺体组织的生理性强化,受多种因素的影...