磁共振心肌应变定量评价心肌淀粉样变及与心肌初始T1值和ECV值的相关性分析

目的:探讨磁共振心肌应变定量评价心肌淀粉样变性(CA)价值及与心肌初始T1值和细胞外容积分数(ECV)值的相关性.方法:对30例CA患者(CA组)、10例可疑CA患者(可疑CA组)、20例肥厚型心肌病患者(HCM组)及40名健康志愿者(健康对照组)行3.0 T心脏磁共振检查(CMR),扫描序列包括心脏电影、T1 map...     

基于心脏磁共振特征追踪技术的心肌应变评估心肌淀粉样变性患者的预后

目的：探讨基于心脏磁共振特征追踪(CMR?FT)技术的左心室心肌应变评估心肌淀粉样变性(CA)患者预后的可行性。方法：回顾性分析我院确诊并行CMR检查的33例轻链型CA患者,使用CVI42软件测量左心室整体和各节段(基底段、中间段、心尖段)水平的3D径向应变(RS)、周向应变(CS)、纵向应变(LS),通过随访生存时间,比较两组患者的预后结果。结果：Kaplan?Meier生存曲线表明RS_Basal、RS_Mid、CS_Basal绝对值降低,患者预后较差(χ²=8.177,8.386,8.386;P=0.004,0.004,0.003)。结论：CMR?FT技术用于左心室的心肌应变,特别是RS_Basal、RS_Mid、CS_Basal对于评估CA患者的预后存在临床价值。     

心肌淀粉样变性MRI及临床特征分析(附4例报道)

目的综合分析临床和/或病理学确诊的心肌淀粉样变性(cardiac amyloidosis, CA)患者的临床特征、心电图(electrocardiogram, ECG)、心脏超声(echocardiology, UCG)、心脏磁共振(cardiac magnetic resonance, CMR),加强对该疾病综合认识,进一步指导临床治疗及科学研究。方法收集4例经心内膜下活检、肾脏、骨髓穿刺活检及临床随访直接或间接证实的心肌淀粉样变性患者,综合分析其影像学及临床特征。结果 4例患者CMR表现为左心室扩大,左心室壁弥漫性均匀增厚并舒张运动受限,延迟增强呈弥漫性心内膜下粉尘样强化3例;表现为双心室扩大,双心室壁弥漫性均匀性增厚并舒张运动受限,延迟增强呈弥漫性心内膜下强化1例。同时,4例均伴有不同程度的房室瓣返流及心包积液。结论心肌淀粉样变性的MRI表现具有特征性,结合临床表现、ECG、UCG等可做出准确诊断,为临床针对性治疗提供可靠依据。     

肝硬化心肌病的CMR与USG研究进展

肝硬化心肌病(CCM)是肝硬化的严重并发症之一,主要表现为心肌对应激的收缩反应受损和/或舒张功能障碍及电生理功能异常。超声心动图(USG)目前广泛应用于CCM的诊断,但CCM发病机制复杂、血流动力学特殊,仅凭单一的USG技术很难完整揭示其结构、功能及心肌内部的改变。心脏磁共振(CMR)成像是目前公认的评估心脏功能的“金标准”,能多维度评价CCM心肌损伤。就USG、CMR技术在CCM心脏结构、功能、心肌纤维化评估及预后判断中的应用予以综述。     

心脏淀粉样变性

各种类型的淀粉样变性均可累及心脏。淀粉样物质沉积和浸润导致心肌细胞萎缩、心肌壁和室间隔肥厚，主要造成限制性心肌病的病理生理学改变，伴心室舒张功能不全，也可侵心脏其它结构。临床表明为充血性心力衰竭、各种类型的心律失常等。本文综述心脏淀粉样变性有关内容及研究进展。     

心脏MR T2WI对心肌淀粉样变性的预后评价

目的本研究旨在探讨心脏MR成像诊断心肌淀粉样变性的价值及其预测性指标。方法 36例心肌淀粉样变性病人和48例健康志愿者行1.5TMR检查。扫描方案包括电     

心脏MR T_2WI对心肌淀粉样变性的预后评价

目的本研究旨在探讨心脏MR成像诊断心肌淀粉样变性的价值及其预测性指标。方法 36例心肌淀粉样变性病人和48例健康志愿者行1.5TMR检查。扫描方案包括电     

基于CMR致心律失常性右室心肌病心肌纤维化程度与心功能的相关性研究

目的 探讨致心律失常性右室发育不良/心肌病(ARVD/C)心室壁心肌纤维化程度与心室容积及心室功能变化的相关性,以期通过纤维化程度评估患者预后.方法 搜集依据最新ARVD/C诊断指南确诊并行心脏磁共振(CMR)检查患者的影像学资料,定量测量心室容积和功能,包括心室舒张末容积(EDV)、心室收缩末容积(ESV)、每搏输出量(SV)、射血分数(EF)及心室舒张末容积指数(EDVI).并分别计算左心室壁、右心室壁及总体心肌纤维化指数,评估其纤维化严重程度.分析心肌纤维化指数与心脏功能指标间的相关性.结果 共35例患者确诊为ARVD/C且行CMR检查,CMR评估ARVD/C患者的LVEF为(48.39±11.10)％,LVEDVI为(111.14±28.66) mL/m2;RVEF为(33.51±13.19)％,RVEDVI为(174.74±64.36) mL/m2.CMR评估左心室壁心肌纤维化指数为(19.7±28.4)％,右心室壁心肌纤维化指数为(50.9±37.7)％,总体心肌纤维化指数为(26.8±28.9)％.左心室壁心肌纤维化指数与LVEF间呈负相关(r=-0.669,P＜0.01),右心室壁心肌纤维化指数与RVEF间呈负相关且相关程度高(r=-0.874,P＜0.01);总体心肌纤维化指数与LVEF、RVEF间亦均呈负相关,相关系数分别为-0.588(P ＜0.01)、-0.835(P ＜0.01).右心室壁心肌纤维化指数、总体心肌纤维化指数与右心室舒张末容积指数(RVEDVI)间均呈显著正相关,相关系数分别为0.846(P ＜0.01)、0.847(P ＜0.01).结论 CMR可以全面评价ARVD/C患者心肌组织特征变化及心脏功能改变;CMR显示的心室壁心肌纤维化程度与心功能存在相关性,可以间接反映心脏功能的变化情况.     

儿童心脏良性肿瘤的CMR影像特征分析

目的 研究儿童心脏良性肿瘤的心脏MR（CMR）特征及其对儿童良性肿瘤的诊断价值。方法 回顾性收集2006年9月-2018年3月于我院进行CMR检查的心脏肿瘤病例资料,共38例心脏良性肿瘤患儿纳入研究,其中男21例,女17例,年龄0.2~153.3个月,中位年龄13个月。分析各病理类型肿瘤在CMR上的特征,包括累及部位、大小、信号特点、血流动力学改变等,以及是否伴发心包和胸腔积液。通过与病理结果对照,计算CMR对心脏良性肿瘤诊断的敏感度和准确度。结果 肿瘤累及心肌、心腔、心包、心室流出道及纵隔,形态大小不一,临床症状与肿瘤发生部位有一定相关性而不具有特异性,但各类肿瘤具有一定的影像特征。所有的心脏肿瘤均被CMR清晰显示,CMR的诊断与病理结果相符的有32例,诊断的敏感度及准确度分别为100%（38/38）和84.21%（32/38）。结论 CMR能够同时提供心脏良性肿瘤的形态学特征及组织学信号特征,对心脏良性肿瘤诊断的敏感性及准确性均较高,是评估心脏肿瘤的重要检查方法。     

冠状动脉斑块与心肌缺血

目的采用心脏MR(CMR)前瞻性研究冠状动脉斑块对心肌缺血的预测价值。方法 52例行冠状动脉造影(CA)后评定为可疑冠心病(CAD)的病人进行了CMR和     

心脏磁共振指纹技术研究进展

心脏磁共振指纹（cMRF）成像是近年新兴的心脏磁共振（CMR）多参数定量成像技术,能够在单次扫描中同时提供心肌组织多参数定量信息。相较于常规CMR定量成像,cMRF具有数据同步采集、多参数成像、图像共同配准以及高效成像等优势,在临床CMR心肌组织特征参数映射中具有良好的应用前景。就cMRF的成像原理、技术优势及未来研究方向进行综述。     

CMR在法洛四联症术后评估中的应用

心脏磁共振（CMR）是法洛四联症（TOF）术后评估的一站式影像诊断工具。随着四维血流CMR技术、CMR-特征追踪技术和纵向弛豫时间定量成像等新技术的发展和应用,CMR可以同时实现心肌运动、血流动力学及心肌组织定量评估,特别对于评价术后TOF（rTOF）早期的血流动力学改变,早期预判rTOF的功能异常,以及反映心肌纤维化与rTOF心律失常的关系是非常有价值的。就上述CMR新技术及其在TOF术后的应用进行综述。     

Differential Diagnosis of Thick Myocardium according to Histologic Features Revealed by Multiparametric Cardiac Magnetic Resonance Imaging

Left ventricular (LV) wall thickening, or LV hypertrophy (LVH), is common and occurs in diverse conditions including hypertrophic cardiomyopathy (HCM), hypertensive heart disease, aortic valve stenosis, lysosomal storage disorders, cardiac amyloidosis, mitochondrial cardiomyopathy, sarcoidosis and athlete’s heart. Cardiac magnetic resonance (CMR) imaging provides various tissue contrasts and characteristics that reflect histological changes in the myocardium, such as cellular hypertrophy, cardiomyocyte disarray, interstitial fibrosis, extracellular accumulation of insoluble proteins, intracellular accumulation of fat, and intracellular vacuolar changes. Therefore, CMR imaging may be beneficial in establishing a differential diagnosis of LVH. Although various diseases share LV wall thickening as a common feature, the histologic changes that underscore each disease are distinct. This review focuses on CMR multiparametric myocardial analysis, which may provide clues for the differentiation of thickened myocardium based on the histologic features of HCM and its phenocopies.     

Quantitative assessment of myocardial T2 relaxation times in cardiac amyloidosis

Purpose

To evaluate cardiac MRI (CMR) in the diagnosis of cardiac amyloidosis by comparing the T2 relaxation times of left ventricular myocardium in a pilot patient group to a normal range established in healthy controls.

Materials and Methods

Forty‐nine patients with suspected amyloidosis‐related cardiomyopathy underwent comprehensive CMR examination, which included assessment of myocardial T2 relaxation times, ventricular function, resting myocardial perfusion, and late gadolinium enhancement (LGE) imaging. T2‐weighted basal, mid, and apical left ventricular slices were acquired in each patient using a multislice T2 magnetization preparation spiral sequence. Slice averaged T2 relaxation times were subsequently calculated offline and compared to the previously established normal range.

Results

Twelve of the 49 patients were confirmed to have cardiac amyloidosis by biopsy. There was no difference in mean T2 relaxation times between the amyloid cases and normal controls (51.3 ± 8.1 vs. 52.1 ± 3.1 msec, P = 0.63). Eleven of the 12 amyloid patients had abnormal findings by CMR, eight having LGE involving either ventricles or atria and four demonstrating resting subendocardial perfusion defects.

Conclusion

CMR is a potentially valuable tool in the diagnosis of cardiac amyloidosis. However, calculation of myocardial T2 relaxation times does not appear useful in distinguishing areas of amyloid deposition from normal myocardium. J. Magn. Reson. Imaging 2009. © 2009 Wiley‐Liss, Inc.     

Kardiale Magnetresonanztomographie

Cardiac magnetic resonance imaging (CMR) has evolved over the past 20 years from a research-based imaging modality to an indispensable routine procedure in cardiac diagnostics. In addition to the morphological representation of cardiac anatomy, whereby only noninvasive multidetector computed tomography (MDCT) is superior, another strength of CMR is the assessment of cardiac function and tissue differentiation. This requires that the radiologist performing the examination and analyzing the results has good knowledge of cardiac and thoracic anatomy and a detailed knowledge of the various cardiovascular diseases, hemodynamics, and pathophysiology. CMR reliably allows determination of a range of easy to determine quantitative parameters such as ventricular ejection fraction and also the valvular regurgitation fraction, which allows objective assessment of cardiac function. Especially the possibility to differentiate inflamed, viable, and ischemic tissue using adenosine stress MRI in the last 10 years has led to routine use of CMR. Even compared to competing nuclear medicine procedures, CMR is important for treatment decision-making and for prognosis estimation, thus, making it an indispensable component of cardiovascular diagnostics.     

Advances in Myocardial Perfusion MR Imaging: Physiological Implications,the Importance of Quantitative Analysis,and Impact on Patient Care in Coronary Artery Disease

Stress myocardial perfusion imaging (MPI) is the preferred test in patients with intermediate-to-high clinical likelihood of coronary artery disease (CAD) and can be used as a gatekeeper to avoid unnecessary revascularization. Cardiac magnetic resonance (CMR) has a number of favorable characteristics, including: (1) high spatial resolution that can delineate subendocardial ischemia; (2) comprehensive assessment of morphology, global and regional cardiac functions, tissue characterization, and coronary artery stenosis; and (3) no radiation exposure to patients. According to meta-analysis studies, the diagnostic accuracy of perfusion CMR is comparable to positron emission tomography (PET) and perfusion CT, and is better than single-photon emission CT (SPECT) when fractional flow reserve (FFR) is used as a reference standard. In addition, stress CMR has an excellent prognostic value. One meta-analysis study demonstrated the annual event rate of cardiovascular death or non-fatal myocardial infarction was 4.9% and 0.8%, respectively, in patients with positive and negative stress CMR. Quantitative assessment of perfusion CMR not only allows the objective evaluation of regional ischemia but also provides insights into the pathophysiology of microvascular disease and diffuse subclinical atherosclerosis. For accurate quantification of myocardial perfusion, saturation correction of arterial input function is important. There are two major approaches for saturation correction, one is a dual-bolus method and the other is a dual-sequence method. Absolute quantitative mapping with myocardial perfusion CMR has good accuracy in detecting coronary microvascular dysfunction. Flow measurement in the coronary sinus (CS) with phase contrast cine CMR is an alternative approach to quantify global coronary flow reserve (CFR). The measurement of global CFR by quantitative analysis of perfusion CMR or flow measurement in the CS permits assessment of microvascular disease and diffuse subclinical atherosclerosis, which may provide improved prediction of future event risk in patients with suspected or known CAD. Multi-institutional studies to validate the diagnostic and prognostic values of quantitative perfusion CMR approaches are required.     

Cardiovascular MRI for the assessment of heart failure: focus on clinical management and prognosis

Cardiovascular MR (CMR) has an emerging role in the noninvasive diagnostic assessment of heart failure (HF). Different imaging sequences allow for a detailed assessment of cardiac morphology, function, myocardial perfusion, tissue characterization, and blood flow measurement. This article reviews the key applications of CMR in HF, with special focus on how CMR may influence the diagnostic and therapeutic approach of HF patients.     

Myocardial Fibrosis in Hypertrophic Cardiomyopathy Demonstrated by Integrated Cardiac F-18 FDG PET/MR

Hypertrophic cardiomyopathy (HCM) is a common condition defined as a diffuse or segmental left ventricular (LV) hypertrophy with a nondilated and hyperdynamic chamber as well as cardiac arrhythmias. Cardiac MR (CMR) imaging is a key modality for evaluation of HCM. In addition to the assessment of LV wall thickness, LV function and aortic flow, CMR is capable of estimation of late gadolinium enhancement (LGE) in affected myocardium which has been shown to have a direct correlation with incidence and severity of arrhythmias in HCM. In patients with HCM, LGE on CMR is presumed to represent intramyocardial fibrosis. Meanwhile, F-18 FDG myocardial PET has been sporadically studied in HCM, mostly for evaluation of the metabolic status of a hypertrophic myocardial segment, especially after interventions or to demonstrate partial myocardial fibrosis. We presented here the case of a 25-year-old male patient referred for simultaneous F-18 FDG cardiac PET/MR for the evaluation of septal hypertrophy. The PET/MR revealed myocardial fibrosis in the septum associated with FDG-defect and LGE.     

The cardiac magnetic resonance (CMR) approach to assessing myocardial viability

Cardiac magnetic resonance (CMR) is a noninvasive imaging method that can determine myocardial anatomy, function, perfusion, and viability in a relative short examination. In terms of viability assessment, CMR can determine viability in a non-contrast enhanced scan using dobutamine stress following protocols comparable to those developed for dobutamine echocardiography. CMR can also determine viability with late gadolinium enhancement (LGE) methods. The gadolinium-based contrast agents used for LGE differentiate viable myocardium from scar on the basis of differences in cell membrane integrity for acute myocardial infarction. In chronic myocardial infarction, the scarred tissue enhances much more than normal myocardium due to increases in extracellular volume. LGE is well validated in pre-clinical and clinical studies that now span from almost a cellular level in animals to human validations in a large international multicenter clinical trial. Beyond infarct size or infarct detection, LGE is a strong predictor of mortality and adverse cardiac events. CMR can also image microvascular obstruction and intracardiac thrombus. When combined with a measure of area at risk like T2-weighted images, CMR can determine infarct size, area at risk, and thus estimate myocardial salvage 1-7 days after acute myocardial infarction. Thus, CMR is a well validated technique that can assess viability by gadolinium-free dobutamine stress testing or late gadolinium enhancement.     

Assessment of myocardial fibrosis and coronary arteries in hypertrophic cardiomyopathy using combined arterial and delayed enhanced CT: comparison with MR and coronary angiography

Objectives

We sought to determine the feasibility and accuracy of dual-source computed tomography (DSCT) in assessing coronary artery disease and myocardial fibrosis of hypertrophic cardiomyopathy (HCM) compared with cardiac magnetic resonance (CMR) imaging and coronary angiography (CA).

Methods

Forty-seven consecutive patients with HCM were prospectively enrolled. DSCT images were acquired in the arterial and late phases following intravenous contrast medium. The CMR and CA were performed within 7 days. Independent blinded readers read each study. Patients were classified according to myocardial delayed enhanced (MDE) CMR, coronary artery stenosis by CA, and arterial and MDE-DSCT. The diagnostic accuracy of DSCT in detecting coronary stenosis and MDE was analysed.

Results

Wall thickness determined by DSCT was strongly correlated with MR results (r?=?0.91). DSCT and CMR MDE showed substantial agreement for the detection of myocardial fibrosis on per-patient and per-segment levels. The CT classification of patients by arterial stenosis and delayed enhancement had excellent agreement with MR and CA methods.

Conclusions

The comprehensive cardiac CT examination provides reliable coronary artery and myocardial assessments. MDE-DSCT is a robust alternative method to MDE-CMR in assessing myocardial fibrosis in HCM particularly in patients with pacemakers or other contraindications to CMR.

Key Points

? Enhanced cardiac CT provides comprehensive assessment of patients with hypertrophic cardiomyopathy (HCM). ? Myocardial delayed enhanced-CT has comparable accuracy to MDE-MR in detecting HCM fibrosis. ? MDE-CT provides a robust alternative for HCM patients with MR contraindications.