心脏磁共振心肌应变在心肌炎中的应用及进展

<正>2009年美国心脏病学会发布了磁共振诊断心肌炎的标准,即“路易斯湖诊断标准”(Lake Louise consensus criteria,LLC)心脏磁共振(cardiac magnetic resonance,CMR)成像纳入心肌炎诊断标准以来,CMR已经成为心肌炎诊断和随访最常用的影像学方法^[1]。由于LLC缺乏定量诊断的局限性^[2],2018年,JACC专家共识推荐在LLC基础上增加定量CMR技术,以提高心肌炎的诊断准确性。定量CMR技术需要额外扫描序列,大大增加了扫描时间。最近,基于心脏磁共振特征追踪技术(feature tracking, FT),利用电影序列,不需要额外扫描序列及时间,     

磁共振波谱技术在脑缺血中的应用价值

CT和磁共振成象技术的应用大大提高了脑缺血性疾病的早期诊断水平,磁共振波谱(MRS)则是唯一可用来在体观察细胞代谢变化的非创伤性技术。文章综述脑缺血时的病理生理改变以及~(31)p和~1H磁共振波谱的特征表现,了解该新技术的临床应用价值。     

磁共振波谱技术在脑缺血中的应用价值

ＣＴ和磁共振成像技术的应用大大提高了脑缺血性疾病的早期诊断水平，磁共振波谱则是唯一可用来在体观察细胞代谢变化的非创伤性技术。文章综述脑缺血时的病理生理改变以及＾３１Ｐ和＾１Ｈ磁共振波谱的特征表现，了解该新技术的临床应用价值。     

心脏磁共振特征追踪技术评估心脏功能的应用价值

心脏磁共振特征追踪(CMR-FT)技术是在心脏磁共振电影序列图像基础上,无创测量心肌应变参数的一种新技术.CMR-FT技术通过定量评估心肌局部和整体的功能,能在亚临床水平发现心肌受损,为疾病早期诊断、风险分层及预后判断提供新途径.目前CMR-FT技术在心肌应变方向的研究发展迅速,已成为心脏磁共振技术中的研究热点.现就C...     

磁共振血流测量在心血管系统的应用及进展

磁共振(MR)血流测量技术拓展了MR对心脏的全面评价能力,尤其是在冠状动脉血流测定方面,近几年,随着MR技术发展及后处理软件的开发应用,MR血流测量技术在心血管系统的临床应用中更加广泛并取得巨大进展.     

氢质子磁共振波谱在帕金森病诊断中的应用近况

氢质子磁共振波谱是无创性测定体内代谢物的技术，能提供相关兴趣区的神经化学信息，从细胞代谢水平研究帕金森病及帕金森综合征，是目前临床和实验室检测手段中一种有价值的研究方法。本文综述了近年来氢质子磁共振波谱检查技术的发展及氢质子磁共振波谱在帕金森病诊断、鉴别诊断及疗效评价中的研究进展。     

心电图测量技术专家共识

心电图参数是判断心电图是否异常的基本指标和主要依据,因此心电图参数测量的规范化十分重要。国际上权威的医学机构及国内、外教科书对心电图测量技术有明确定义[1～9]。1998年中华医学会心电生理和起搏分会曾组织国内知名的心血管专家及心电图工作者对心电图测量的标准进行研讨,并达成共识[10],对推动我国心电图测量的标准化起了重要作用。鉴于近年来心电学检测技术的迅猛进展,某些传统的测量方法和定义已经更新[11, 12],为此,特邀请了有关的知名心血管与心电学专家起草了心电图测量技术指南-专家共识。经过专家工作组的多次讨论、修定,最终完成这一专家共识的定稿。希望该共识能够进一步推动我国心电图测量技术的标准化和规范化,同时希望广大同道在实践应用中,对该专家共识提出积极的修正建议,以便专家共识再版时能进一步完善。     

磁共振扩散加权成像在肝脏疾病中的应用

磁共振扩散加权成像是一种可反映活体内水分子扩散特征的功能成像方法,能间接反映细胞的密度和细胞膜的完整性及毛细血管灌注情况。介绍了该技术在肝脏病变中的主要应用,并重点介绍其在肝细胞癌、肝纤维化的分期及肿瘤疗效监测中的应用。指出这种无需注射对比剂的技术虽仍有不足,但随着软、硬件的发展,将有广阔的应用前景。     

2014欧洲高血压学会动态血压监测指南解读

<正>动态血压监测,作为目前state-of-art血压测量技术,已越来越被广泛地应用于高血压的诊断和治疗管理,因为它不仅是鉴别诊断白大衣性高血压及隐蔽性高血压的标准方法,还可以全面反映不同时间段、多种状态下,如日常工作、运动及休息睡眠状态下的血压水平与血压波动特点。2013年欧洲高血压学会血压测量工作组集34位各国专家智慧,综合600多篇动态血压相关文章的研究证据,发表了动态血压的专家共识及     

磁共振测量海马体积在帕金森病中的应用

磁共振测量海马体积主要有手工、半自动和自动测量3种方法.应用磁共振测量海马体积发现无痴呆的帕金森病患者存在海马萎缩,其程度轻于帕金森病痴呆,轻度认知障碍伴海马萎缩被认为是帕金森病患者痴呆前的亚临床标志;帕金森病痴呆海马萎缩的程度与路易体痴呆相似,均比阿尔茨海默病海马萎缩的程度轻.磁共振测量海马体积为帕金森病及其相关认知障碍的诊断及鉴别诊断开辟了新的途径.     

Canadian Society for Cardiovascular Magnetic Resonance (CanSCMR) Recommendations for Cardiovascular Magnetic Resonance Image Analysis and Reporting

Cardiovascular magnetic resonance (CMR) imaging is a rapidly developing technology that is becoming increasingly important in the diagnostic assessment of heart disease. Recognizing the need for recommendations to optimize the use of this technique, the Canadian Society for Cardiovascular Magnetic Resonance developed a task force to generate recommendations on the clinical use of parameters acquired by CMR imaging and how they should be reported. This article is the consensus report generated by the task force. The online material of this report provides such parameters for all relevant clinical settings, including pediatric and congenital applications. It considers the current clinical role of CMR, general requirements for CMR imaging, components of CMR studies, quantitative CMR image analysis, and appropriate contents of CMR reports. The recommendations are based on previously published recommendations on analysis and reporting and are the first of their kind. It is hoped that the use of these recommendations to guide daily clinical routine will help institutions offering CMR to adhere to high standards of quality according to the present state of the art.     

Myocardial Extracellular Volume Quantification by Cardiovascular Magnetic Resonance and Computed Tomography

Purpose of review

This review article discusses the evolution of extracellular volume (ECV) quantification using both cardiovascular magnetic resonance (CMR) and computed tomography (CT).

Recent findings

Visualizing diffuse myocardial fibrosis is challenging and until recently, was restricted to the domain of the pathologist. CMR and CT both use extravascular, extracellular contrast agents, permitting ECV measurement. The evidence base around ECV quantification by CMR is growing rapidly and just starting in CT. In conditions with high ECV (amyloid, oedema and fibrosis), this technique is already being used clinically and as a surrogate endpoint. Non-invasive diffuse fibrosis quantification is also generating new biological insights into key cardiac diseases.

Summary

CMR and CT can estimate ECV and in turn diffuse myocardial fibrosis, obviating the need for invasive endomyocardial biopsy. CT is an attractive alternative to CMR particularly in those individuals with contraindications to the latter. Further studies are needed, particularly in CT.

     

Advances in clinical applications of cardiovascular magnetic resonance imaging

Cardiovascular magnetic resonance (CMR) is an evolving technology with growing indications within the clinical cardiology setting. This review article summarises the current clinical applications of CMR. The focus is on the use of CMR in the diagnosis of coronary artery disease with summaries of validation literature in CMR viability, myocardial perfusion, and dobutamine CMR. Practical uses of CMR in non-coronary diseases are also discussed.     

Diffuse Myocardial Fibrosis and Diastolic Function in Aortic Stenosis

ObjectivesThe aim of this study was to investigate the relationship between extracellular volume fraction (ECV), a noninvasive parameter that quantifies the degree of diffuse myocardial fibrosis on cardiac magnetic resonance (CMR), and left ventricular diastolic dysfunction (LVDD) in patients with aortic stenosis (AS).BackgroundMyocardial fibrosis on invasive myocardial biopsy is associated with LVDD. However, there is a paucity of data on the association between noninvasively quantified diffuse myocardial fibrosis and the degree of LVDD and how these are related to symptoms and long-term prognosis in patients with AS.MethodsPatients with moderate or severe AS (n = 191; mean age 68.4 years) and 30 control subjects without cardiovascular risk factors underwent CMR. LVDD grade was evaluated using echocardiography according to the 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines. Clinical outcomes were defined as a composite of all-cause mortality or hospitalization for heart failure aggravation.ResultsPatients in higher ECV quintiles had a significantly higher prevalence of LVDD. Higher ECV was particularly associated with decreased myocardial relaxation (septal e′ <7 cm/s) and increased LV filling pressure (E/e′ ratio ≥15). Although both impaired diastolic function and higher ECV were significantly associated with a worse degree of dyspnea, patients with higher ECV showed greater dyspnea within the same grade of LVDD. During a median follow-up period of 5.6 years, 37 clinical events occurred. Increased ECV, as well as lower septal e′ and higher E/septal e′ ratio, were independent predictors of clinical events, irrespective of age, AS severity, aortic valve replacement, and left ventricular (LV) ejection fraction. ECV provided incremental prognostic value on top of clinical factors and LV systolic and diastolic function.ConclusionsDiffuse myocardial fibrosis, assessed using ECV on CMR, was associated with LVDD in patients with AS, but both ECV and LV diastolic function parameters provided a complementary explanation for dyspnea and clinical outcomes. Concomitant assessment of both LVDD and diffuse myocardial fibrosis may further identify patients with AS with greater symptoms and worse prognosis.     

Documento de consenso sobre codificação de exames de ressonância magnética cardíaca em Portugal

One of the obstacles to more frequent and appropriate use of cardiac magnetic resonance (CMR) in Portugal has been the lack of specific codes that accurately describe these examinations as they are currently performed. In this consensus document, recommendations are made for updating and standardizing CMR codes in Portugal. Guidance on which techniques and codes should be used in the most common clinical scenarios is also provided.     

Cardiac Magnetic Resonance Imaging for the Investigation of Cardiovascular Disorders. Part 1: Current Applications

Cardiac magnetic resonance imaging is a robust noninvasive technique for investigating cardiovascular disorders. The evolution of cardiac magnetic resonance and its widening span of diagnostic and prognostic applications have generated excitement as well as uncertainty regarding its potential clinical use and its role vis-à-vis conventional imaging techniques. The purpose of this evidence-based review is to discuss some of these issues by highlighting the current (Part 1) and emerging (Part 2) applications of cardiac magnetic resonance. Familiarity with the versatility and usefulness of cardiac magnetic resonance will facilitate its wider clinical acceptance for improving the management of cardiovascular disorders.Key words: Cardiomyo­pathies/diagnosis, fibrosis, gadolinium DTPA/diagnostic use, hypertrophy, left ventricular/diagnosis, magnetic resonance angiography, magnetic resonance imaging/standards, myocarditis/diagnosis, pericarditis, constrictive/diagnosis, sarcoidosis, stroke volume, ventricular dysfunction, left/diagnosisCardiac magnetic resonance imaging (CMR) has emerged as a robust noninvasive technique for the investigation of cardiovascular disorders. Several technical advances have facilitated the growth of CMR by enabling high-quality diagnostic imaging despite the challenges inherent to cardiac imaging: cardiorespiratory motion and flowing blood. Considerable research evidence and years of clinical experience have shown the diagnostic and prognostic usefulness of CMR in a wide spectrum of cardiovascular disorders. The coming-of-age of CMR and its widening span of applications have generated excitement, as well as uncertainty, regarding its potential clinical use and its role vis-à-vis conventional imaging techniques. The purpose of this article is to highlight the current (Part 1) and emerging (Part 2) applications of CMR, in order to assist the referring physician in the decision-making process.     

Extracellular Volume in Primary Mitral Regurgitation

ObjectivesThis study used cardiovascular magnetic resonance (CMR) to evaluate whether elevated extracellular volume (ECV) was associated with mitral valve prolapse (MVP) or if elevated ECV was a consequence of remodeling independent of primary mitral regurgitation (MR) etiology.BackgroundReplacement fibrosis in primary MR is more prevalent in MVP; however, data on ECV as a surrogate for diffuse interstitial fibrosis in primary MR are limited.MethodsPatients with chronic primary MR underwent comprehensive CMR phenotyping and were stratified into an MVP cohort (>2 mm leaflet displacement on a 3-chamber cine CMR) and a non-MVP cohort. Factors associated with ECV and replacement fibrosis were assessed. The association of ECV and symptoms related to MR and clinical events (mitral surgery and cardiovascular death) was ascertained.ResultsA total of 424 patients with primary MR (229 with MVP and 195 non-MVP) were enrolled. Replacement fibrosis was more prevalent in the MVP cohort (34.1% vs. 6.7%; p < 0.001), with bi-leaflet MVP having the strongest association with replacement fibrosis (odds ratio: 10.5; p < 0.001). ECV increased with MR severity in a similar fashion for both MVP and non-MVP cohorts and was associated with MR severity but not MVP on multivariable analysis. Elevated ECV was independently associated with symptoms related to MR and clinical events.ConclusionsAlthough replacement fibrosis was more prevalent in MVP, diffuse interstitial fibrosis as inferred by ECV was associated with MR severity, regardless of primary MR etiology. ECV was independently associated with symptoms related to MR and clinical events. (DeBakey Cardiovascular Magnetic Resonance Study [DEBAKEY-CMR]; NCT04281823)     

Meeting highlights of the 8th Annual Scientific Sessions of the Society For Cardiovascular Magnetic Resonance, January 21 to 23, 2005

Parallel tracks for clinical scientists, basic scientists, and pediatric imagers was the novel approach taken for the highly successful 8th Annual Scientific Sessions of the Society for Cardiovascular Magnetic Resonance, held in San Francisco, California, January 21 to 23, 2005. Attendees were immersed in information on the latest scientific advances in cardiovascular magnetic resonance (CMR) from mice to man and technological advances from systems with field strengths from 0.5 T to 11.7 T. State-of-the-art applications were reviewed, spanning a wide range from molecular imaging to predicting outcome with CMR in large patient populations.     

Regional Replacement and Diffuse Interstitial Fibrosis in Aortic Regurgitation: Prognostic Implications From Cardiac Magnetic Resonance

ObjectivesThis study used cardiac magnetic resonance (CMR) to assess left ventricular (LV) remodeling in chronic aortic regurgitation (AR) to identify both forms of myocardial fibrosis and examine its association with clinical outcomes.BackgroundChronic AR leads to LV remodeling, which is associated with 2 forms of myocardial fibrosis: regional replacement fibrosis that is directly imaged by late gadolinium enhancement (LGE) CMR; and diffuse interstitial fibrosis, which can be inferred by T1 mapping techniques.MethodsPatients with chronic AR who were undergoing contrast CMR with T1 mapping for valve assessment from 2011 to 2018 were enrolled. Patients with a confounding etiology of myocardial fibrosis were excluded. In addition to quantification of AR severity and LV volumetrics, LGE and T1 mapping pre- and post-contrast were performed to measure extracellular volume (ECV) and indexed ECV (iECV). Patients were followed up longitudinally to assess for the composite event of death and the need for aortic valve replacement.ResultsA total of 177 patients with isolated chronic AR were included (66% males, median age 58 years [IQR: 47.0-68.0 years]) with a median follow up of 2.5 years (IQR: 1.07-3.56 years). The iECV significantly increased with AR severity (P < 0.001), whereas ECV and replacement fibrosis did not (P = NS). On multivariate analysis, iECV remained associated with the composite event (P = 0.01). On Kaplan-Meier analysis stratified by AR regurgitant fraction (RF) and iECV, patients with AR RF severity ≥30% and iECV ≥24 mL/m² demonstrated the highest event rate.ConclusionsAmong CMR biomarkers of fibrosis, iECV was more closely associated than replacement fibrosis or ECV with survival free of aortic valve replacement.