The additional value of gadolinium-enhanced MRI to standard assessment for cardiac involvement in patients with pulmonary sarcoidosis

AIM: To determine whether gadolinium-enhanced cardiac MRI (CMR) was of additional diagnostic value to standard assessment in patients with sarcoidosis who underwent evaluation for cardiac involvement. METHODS: We reviewed the findings in patients with pulmonary sarcoidosis who had been assessed with ECG, Doppler echocardiography, 201Tl scintigraphy, and CMR from 2002 to 2004. RESULTS: Of the 55 evaluated patients, standard evaluation diagnosed cardiac involvement in 13 patients while CMR diagnosed myocardial scarring (mean +/- SD, 2.5 +/- 1.9 segments) [all 6 patients] and impaired systolic left ventricular function (1 patient) in an additional 6 patients. The extent of delayed enhancement correlated with disease duration (p < 0.05), ventricular dimensions and function (p < 0.001), severity of mitral regurgitation (p < 0.05), and the presence of ventricular tachycardias (p < 0.001). Patients in whom cardiac involvement was diagnosed only with CMR had less myocardial scarring and functional impairment (p < 0.05) compared to patients with a diagnosis made by standard assessment. CONCLUSION: CMR provides an accurate estimation of the extent of cardiac involvement and may reveal signs of early infiltration that are not detected by standard assessment. The extent of late enhancement with gadolinium relates to the severity of cardiac involvement and may therefore have prognostic implications.     

Role of cardiac MRI in nonischemic cardiomyopathies

Cardiac magnetic resonance (CMR) with its higher spatial resolution is considered the gold standard for evaluating ventricular mass, volumes, and ejection fraction. CMR can be used for accurate diagnosis of several conditions, especially cardiomyopathies. The purpose of this article is to review the utility of CMR in the diagnosis and management of nonischemic cardiomyopathies. We have reviewed both common and rare types of nonischemic cardiomyopathies in detail and elaborated on the specific CMR findings in each. We believe that CMR is an invaluable tool, not only in differentiating nonischemic from ischemic cardiomyopathy, but also in aiding the accurate diagnosis and management of the subtype of nonischemic cardiomyopathy. CMR should routinely be integrated in the diagnostic workup of various cardiomyopathies.     

A clinical cardiovascular magnetic resonance service: operational considerations and the basic examination

Cardiovascular magnetic resonance (CMR) is now considered the "gold standard" for the assessment of regional and global systolic function, myocardial infarction and viability, and congenital heart disease. At specialized centers, CMR has become a clinical workhorse for the evaluation of ischemic heart disease and for heart failure and cardiomyopathies. Despite this versatility, general acceptance of CMR in cardiovascular medicine has progressed slowly. This article provides a basic understanding of important operational considerations when starting a CMR service and describes a conceptual framework of the components of a CMR examination.     

A study of the 16-Segment Regional Wall Motion Scoring Index and biplane Simpson's rule for the calculation of left ventricular ejection fraction: a comparison with cardiac magnetic resonance imaging

Aims: Accurate calculation of left ventricular ejection fraction (LVEF) is important for diagnostic, prognostic and therapeutic reasons. Cardiac magnetic resonance (CMR) is the reference standard for LVEF calculation, followed by real time three‐dimensional echocardiography (RT3DE). Limited availability of CMR and RT3DE leaves Simpson's rule as the two‐dimensional echocardiography (2DE) standard by which LVEF is calculated. We investigated the accuracy of the 16‐Segment Regional Wall Motion Score Index (RWMSI) as an alternative method for calculating LVEF by 2DE and compared this to Simpson's rule and CMR. Methods and Results: The 2D echocardiograms of 110 patients were studied (LVEF range: 7–74%); 57 of these underwent CMR. A RWMS was applied, based on the consensus opinion of two experienced cardiologists, to each of 16 American Heart Association myocardial segments (RWMSI: hyperkinesis = 3; normal regional contraction = 2; mild hypokinesis = 1.25; severe hypokinesis = 0.75; akinesis = 0; dyskinesis =–1). LVEF was calculated by: LVEF(%) =Σ(16segRWMS)/16×30. LVEF was calculated by Simpson's rule and CMR using standard methods. Results were correlated against CMR. Intertechnique agreement was examined. A P value of<0.05 was considered significant. RWMSI‐LVEF correlated strongly with Biplane Simpson's rule (P< 0.001, r = 0.915). RWMSI‐LVEF had a strong correlation to CMR (P < 0.001, r = 0.916); Simpson's rule‐LVEF had a moderate correlation to CMR (P< 0.001, r = 0.647). In patients with LV dysfunction (EF < 55%), on linear regression analysis, RWMSI‐LVEF had a better correlation with CMR than Simpson's rule. Further more Simpson's rule overestimated LVEF compared to CMR (mean difference: –6.12 ± 16.44, P = 0.002) whereas RWMSI did not (mean difference: 2.58 ± 14.80, P = NS). Conclusion: RWMSI‐LVEF correlates strongly with CMR with good intertechnique agreement. In centers where CMR and RT3DE are not readily available, the use by experienced individuals, of the RWMSI for calculating LVEF may be a more simple, accurate, and reliable alternative to Simpson's rule. (Echocardiography 2011;28:597‐604)     

CMR in Patients With Severe Myocarditis: Diagnostic Value of Quantitative Tissue Markers Including Extracellular Volume Imaging

ObjectivesThis study evaluated the accuracy of T2, T1, and extracellular volume (ECV) quantification as novel quantitative tissue markers in comparison with standard “Lake-Louise” cardiac magnetic resonance (CMR) criteria to diagnose myocarditis.BackgroundNovel approaches using T2 and T1 mapping may overcome the limitations of signal intensity-based parameters, which would potentially result in a better diagnostic accuracy compared with standard CMR techniques in suspected myocarditis.MethodsCMR was performed in 104 patients with myocarditis and 21 control subjects at 1.5-T. Patients with myocarditis underwent CMR 2 weeks (interquartile range: 1 to 7 weeks) after presentation with new-onset heart failure (n = 66) or acute chest pain (n = 38). T2 and T1 mapping were implemented into a standard protocol including T2-weighted (T2w), early gadolinium enhancement (EGE) CMR, and late gadolinium enhancement (LGE) CMR. T2 quantification was performed using a free-breathing, navigator-gated multiecho sequence. T1 quantification was performed using the modified Look-Locker inversion recovery sequence before and after administration of 0.075 mmol/kg gadobenate dimeglumine. T2, T1, and ECV maps were generated using a plug-in for the OsiriX software (Pixmeo, Bernex, Switzerland) to calculate mean global myocardial T2, T1, and ECV values.ResultsThe diagnostic accuracies of conventional CMR were 70% (95% confidence interval [CI]: 61% to 77%) for T2w CMR, 59% (95% CI: 56% to 73%) for EGE, and 67% (95% CI: 59% to 75%) for LGE. The diagnostic accuracies of mapping techniques were 63% (95% CI: 53% to 73%) for myocardial T2, 69% (95% CI: 60% to 76%) for native myocardial T1, and 76% (95% CI: 68% to 82%) for global myocardial ECV. The diagnostic accuracy of CMR was significantly improved to 90% (95% CI: 84% to 95%) by a stepwise approach, using the presence of LGE and myocardial ECV ≥27% as diagnostic criteria, compared with 79% (95% CI: 71% to 85%; p = 0.0043) for the Lake-Louise criteria.ConclusionsIn patients with clinical evidence for subacute, severe myocarditis, ECV quantification with LGE imaging significantly improved the diagnostic accuracy of CMR compared with standard Lake-Louise criteria.     

Adherence to the standard dose of imatinib, rather than dose adjustment based on its plasma concentration, is critical to achieve a deep molecular response in patients with chronic myeloid leukemia

The correlation between imatinib (IM) trough plasma concentration (Cmin) and clinical response was assessed in patients with chronic-phase chronic myeloid leukemia. The Cmin correlated with neither the achievement of complete cytogenetic response (977 vs. 993 ng/ml, P = 0.48) nor a major molecular response (1,044 vs. 818 ng/ml, P = 0.17). Although this was significantly higher in patients with complete molecular response (CMR) than in those without (1,430 vs. 859 ng/ml, P = 0.04), the difference was not significant in the sub-population treated with a standard dose of IM (400 mg/day). Finally, multivariate analysis showed that the IM standard dose, but not Cmin, was predictive of the achievement of CMR. We thus suggest that, in practical clinics at least, adherence to the standard dose is the most important factor for the achievement of CMR.     

The Role of MRI in Assessing Risk of Future Cardiovascular Disease Events, Including Heart Failure

Cardiovascular magnetic resonance (CMR) is the currently available gold standard non-invasive imaging modality for determining myocardial anatomy, structure and function. In this article, we discuss the role of CMR in evaluation of patients with cardiovascular disease with a particular emphasis on the additional information obtained from the recent developments in the imaging techniques.     

Evaluation of the accuracy of gadolinium-enhanced cardiovascular magnetic resonance in the diagnosis of cardiac sarcoidosis

OBJECTIVES: This study analyzed the accuracy of gadolinium-enhanced cardiovascular magnetic resonance (CMR) for the diagnosis of cardiac sarcoidosis (CS). BACKGROUND: The diagnosis of CS was made according to the guidelines of the Japanese Ministry of Health and Welfare (1993); CMR has not been incorporated into the guidelines, and the diagnostic accuracy of CMR for the diagnosis of CS has not yet been evaluated. METHODS: We performed an analysis of 12-lead electrocardiograms (ECGs), 24-h ambulatory ECGs, echocardiograms, thallium scintigrams, and gadolinium-enhanced CMR studies in 58 biopsy-proven pulmonary sarcoidosis patients assessed for CS. The diagnostic accuracy of CMR for CS was determined using modified Japanese guidelines as the gold standard. RESULTS: The diagnosis of CS was made in 12 of 58 patients (21%); CMR revealed late gadolinium enhancement (LGE), mostly involving basal and lateral segments (73%), in 19 patients. In 8 of the 19 patients, scintigraphy was normal, while patchy LGE was present. The sensitivity and specificity of CMR were 100% (95% confidence interval, 78% to 100%) and 78% (95% confidence interval, 64% to 89%), and the positive and negative predictive values were 55% and 100%, respectively, with an overall accuracy of 83%. CONCLUSIONS: In patients with sarcoidosis, CMR is a useful diagnostic tool to determine cardiac involvement. New diagnostic guidelines should include CMR.     

Assessment of myocardial viability by cardiovascular magnetic resonance

Patients with ischemic heart disease may have left ventricular (LV) dysfunction due to reversible or irreversible causes. The ability to distinguish viable myocardium with dysfunction due to a reversible etiology (hibernation, stunning) from nonviable scar is critical for determining proper management of the patient. Cardiovascular magnetic resonance (CMR) is a technique that has been established to be useful for the detection of myocardial viability and advancements in the field promise to further increase its utility. In this review we describe the features of CMR that make it suited for this purpose and outline promising developments that may soon make CMR the reference standard for viability assessment.     

Cardiovascular Magnetic Resonance for Patients With COVID-19

COVID-19 is associated with myocardial injury caused by ischemia, inflammation, or myocarditis. Cardiovascular magnetic resonance (CMR) is the noninvasive reference standard for cardiac function, structure, and tissue composition. CMR is a potentially valuable diagnostic tool in patients with COVID-19 presenting with myocardial injury and evidence of cardiac dysfunction. Although COVID-19–related myocarditis is likely infrequent, COVID-19–related cardiovascular histopathology findings have been reported in up to 48% of patients, raising the concern for long-term myocardial injury. Studies to date report CMR abnormalities in 26% to 60% of hospitalized patients who have recovered from COVID-19, including functional impairment, myocardial tissue abnormalities, late gadolinium enhancement, or pericardial abnormalities. In athletes post–COVID-19, CMR has detected myocarditis-like abnormalities. In children, multisystem inflammatory syndrome may occur 2 to 6 weeks after infection; associated myocarditis and coronary artery aneurysms are evaluable by CMR. At this time, our understanding of COVID-19–related cardiovascular involvement is incomplete, and multiple studies are planned to evaluate patients with COVID-19 using CMR. In this review, we summarize existing studies of CMR for patients with COVID-19 and present ongoing research. We also provide recommendations for clinical use of CMR for patients with acute symptoms or who are recovering from COVID-19.     

Importance of standardized assessment of late gadolinium enhancement for quantification of infarct size by cardiac magnetic resonance: implications for comparison with electrocardiogram

Background

Cardiac magnetic resonance (CMR) is currently considered the reference standard for in vivo assessment of myocardial infarction (MI). There is, however, no international consensus on how MI quantification from CMR should be performed. The aim of this study was to test how previously published manual quantification of MI using CMR images compares with MI quantification using a semiautomated, validated method and how this impacts the relationship with MI size estimated by 12-lead electrocardiogram (ECG).

Methods

Twenty-five patients, from a previously published cohort, were included in the study. All patients had presented with clinical signs of acute coronary syndrome 6 to 12 months before undergoing a CMR examination. The patients had a standard 12-lead ECG recorded at the time of the CMR examination. The previously reported manually quantified MI size was compared with MI size determined using a semiautomated method validated by computer phantom data, experimental in vivo and ex vivo data, and patient data. The MI sizes from the 2 CMR approaches were then compared with the ECG-estimated MI size.

Results

There was a strong correlation between MI size determined with the 2 CMR methods (r² = 0.94, P < .001). There was, however, a systematic overestimation of MI size of approximately 50% by the previously published manually quantified MI size compared with the semiautomated method. This affected the comparison with estimated MI size by ECG, which showed a significant underestimation of MI size compared with manual CMR measurements, but no bias compared with the semiautomated CMR method.

Conclusions

Manual quantification of MI size by CMR can differ significantly from semiautomated, validated methods taking partial volume effects into account and can lead to erroneous conclusions when compared with ECG.     

Assessment of Left Ventricular Mass and Hypertrophy by Cardiovascular Magnetic Resonance Imaging in Pediatric Hypertension

Cardiovascular magnetic resonance (CMR) imaging in adults is considered the gold standard for assessment of left ventricular mass (LVM) and left ventricular hypertrophy (LVH). The authors aimed to evaluate agreement of LVM measurements and LVH determination between echocardiography (ECHO) and CMR imaging in children with hypertension (HTN) confirmed by 24‐hour ambulatory blood pressure monitoring (ABPM). The children (n=22) underwent contemporaneous ECHO, CMR imaging, and ABPM. Patients had a mean body mass index of 30.9±7.5 (kg/m²), and 81.8% had severe HTN. LVM measured by ECHO was 189.6±62.1 g and by CMR imaging was 164.6±44.7 g (P<.0001). Bland‐Altman analysis revealed significant variability between ECHO and CMR imaging in the measurement of LVM. Interobserver error was higher with ECHO than with CMR imaging. ECHO had high sensitivity and low specificity in LVH determination. In conclusion, ECHO overestimates LVM and is less accurate in measuring LVM as compared with CMR imaging in children with HTN. Further prospective study using CMR imaging to assess LVM in children is warranted.     

Imaging of ventricular function by cardiovascular magnetic resonance

Over the past 15 years, cardiac magnetic resonance imaging (CMR) has vaulted to the forefront as the ideal diagnostic modality for the evaluation of both left and right ventricular function. The accumulated literature supports this contention for the left ventricle. However, for the right ventricle, typically poorly visualized accurately by traditional imaging techniques, CMR has emerged as the test of choice. Although earlier CMR sequences have become even more robust, resulting in further improvements in spatial and temporal resolution, CMR has avidly remained the gold standard. Yet, these attributes that have so benefited investigations of the systole need not be so constrained. In this review, we discuss recent applications of CMR to the study of lusitropy, demonstrating the potential for further advances in our understanding of diastole.     

Cardiovascular magnetic resonance and the evaluation of heart failure

Cardiovascular magnetic resonance (CMR) has established itself as probably the single best way of phenotyping the failing heart. It is the accepted gold standard for measuring cardiac function, volumes, and mass, but within the same scan session additional techniques are available for greater definition. Tissue characterization with the contrast agent gadolinium is well validated and allows the precise visualization and quantification of myocardial infarction. This can be used for viability assessment and to determine heart failure etiology. Dobutamine stress CMR and CMR perfusion hold advantages over conventional techniques. The new frontiers of CMR in heart failure hold the promise of unique insights quantifying myocardial iron, nonischemic fibrosis, microvascular perfusion, plaque characterization, and CMR-targeted intervention. The development and validation of these techniques represent major research challenges for the future. From a clinical perspective, an equal challenge is in increasing the availability of the modality for patients and physicians.     

Diagnostik der koronaren Herzerkrankung mit Computer- und Magnetresonanztomographie

Coronary angiography by computed tomography (CTCA) is most suitable for symptomatic patients with an intermediate likelihood to exclude a coronary stenosis as the cause of the symptoms. It would also be appropriate in a patient in whom an equivoval stress test result has led to uncertainty about the patient’s further management. CTCA may occasionally be acceptable in a high risk symptomatic patient who refuses the necessary invasive coronary angiography if the results of CTCA are likely to alter patient management. The main indication for cardiac magnetic resonance imaging (CMR) is for pharmacologic stress testing. If such a test is indicated, dobutamine stress CMR is an alternative to stress echocardiography and adenosine perfusion CMR is the alternative to nuclear myocardial perfusion imaging but without radiation. Late gadolinium enhancement CMR is the current gold standard for the assessment of myocardial scars and hence is well suited to predict recovery of function in dysfunctional myocardial regions following revascularisation (viability testing).     

The role of cardiovascular magnetic resonance in heart failure

Cardiovascular Magnetic Resonance (CMR) is an accepted gold standard for non-invasive, accurate, and reproducible assessment of cardiac mass and function. The interest in its use for viability, myocardial perfusion and coronary artery imaging is also widespread and growing rapidly as the hardware and expertise becomes available in more centres, and the scans themselves become more cost effective. In patients with heart failure, accurate and reproducible serial assessment of remodelling is of prognostic importance and the lack of exposure to ionizing radiation is helpful. The concept of an integrated approach to heart failure and its complications using CMR is fast becoming a reality, and this will be tested widely in the coming few years, with the new generation of dedicated CMR scanners.     

The Role of Cardiac MR in New-Onset Heart Failure

In patients with heart failure, cardiovascular magnetic resonance imaging (CMR) allows a multifaceted approach to cardiac evaluation by enabling an assessment of morphology, function, perfusion, viability, tissue characterization, and blood flow during a single comprehensive examination. Given its accuracy and reproducibility, many believe CMR is the reference standard for the noninvasive assessment of ventricular volumes, mass, and function, and offers an ideal means for the serial assessment of disease progression or treatment response in individual patients. Delayed-enhancement (DE)-CMR provides a direct assessment of myopathic processes. This permits a fundamentally different approach than that traditionally taken to ascertaining the etiology of cardiomyopathy, which is vital in patients with nonischemic cardiomyopathy and incidental coronary artery disease and patients with mixed, ischemic and nonischemic cardiomyopathy. Precise tissue characterization with DE-CMR also improves the diagnosis of left ventricular thrombus, for which it is the emerging clinical reference standard. There is a growing body of literature on the utility of CMR for patient risk stratification, and its potential role in important management decisions such as for cardiac resynchronization therapy and defibrillator placement.     

Emerging MRI Methods in Translational Cardiovascular Research

Cardiac magnetic resonance imaging (CMR) has become a reference standard modality for imaging of left ventricular (LV) structure and function and, using late gadolinium enhancement, for imaging myocardial infarction. Emerging CMR techniques enable a more comprehensive examination of the heart, making CMR an excellent tool for use in translational cardiovascular research. Specifically, emerging CMR methods have been developed to measure the extent of myocardial edema, changes in ventricular mechanics, changes in tissue composition as a result of fibrosis, and changes in myocardial perfusion as a function of both disease and infarct healing. New CMR techniques also enable the tracking of labeled cells, molecular imaging of biomarkers of disease, and changes in calcium flux in cardiomyocytes. In addition, MRI can quantify blood flow velocity and wall shear stress in large blood vessels. Almost all of these techniques can be applied in both pre-clinical and clinical settings, enabling both the techniques themselves and the knowledge gained using such techniques in pre-clinical research to be translated from the lab bench to the patient bedside.     

Cardiac magnetic resonance imaging in Turner syndrome

Girls and women with Turner syndrome (TS) have a highly increased morbidity as the result of cardiovascular disease, both congenital and acquired. Increased clinical use of cardiac magnetic resonance imaging (CMR) in patients with TS over recent years has allowed for characterization of disease not always possible with standard imaging modalities, such as echocardiography (echo). In this review, we discuss the current literature regarding CMR in patients with TS and guidelines for its use.     

Volume measurement by CARTO compared with cardiac magnetic resonance.

AIMS: The CARTO electrophysiological mapping system has demonstrated accurate results for end-diastolic ventricular volumes in casts and animals. However, in humans, a comparison with cardiac magnetic resonance (CMR), the non-invasive gold standard for volumetric analysis, has not yet been performed. METHODS AND RESULTS: A total of 34 (29 male) heart failure patients (NYHA class III/IV) underwent an electrophysiological mapping procedure with the CARTO system in the left ventricle (LV) (n = 34) and right ventricle (RV) (n = 12) and CMR for RV and LV end-diastolic volume (RVEDV and LVEDV) measurements another day. Mean LVEDV was comparable between CMR and CARTO (328 +/- 95 and 320 +/- 92 mL, respectively; P = NS), whereas RV volumes measured by CARTO were larger (CMR 140 +/- 48 vs. CARTO 176 +/- 47 mL; P < 0.01). Overall, we found a good correlation between CMR and CARTO measurements for both chambers; however, the Bland-Altman analysis showed a non-interchangeability of these methods. Measurement differences were independent of chamber size, but significantly affected by the number of acquired mapping points. CONCLUSION: Although CMR and CARTO showed a good correlation in the measurement of RVEDV and LVEDV in a group of heart failure patients, the clinical interchangeability of the two methods may be questioned.