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Objectives: This review and meta-analysis reviews the prognostic value of cardiac magnetic resonance (CMR) in nonischemic dilated cardiomyopathy (DCM)., Background: Late gadolinium-enhanced (LGE) CMR is a noninvasive method to determine the underlying cause of DCM and previous studies reported the prognostic value of the presence of LGE to identify patients at risk of major adverse cardiovascular events., Methods: PubMed was searched for studies describing the prognostic implication of LGE in patients with DCM for the specified endpoints cardiovascular mortality, major ventricular arrhythmic events including appropriate implantable cardioverter-defibrillator therapy, rehospitalization for heart failure, and left ventricular reverse remodeling., Results: Data from 34 studies were included, with a total of 4,554 patients. Contrast enhancement was present in 44.8% of DCM patients. Patients with LGE had increased cardiovascular mortality (odds ratio [OR]: 3.40; 95% confidence interval [CI]: 2.04 to 5.67), ventricular arrhythmic events (OR: 4.52; 95% CI: 3.41 to 5.99), and rehospitalization for heart failure (OR: 2.66; 95% CI: 1.67 to 4.24) compared with those without LGE. Moreover, the absence of LGE predicted left ventricular reverse remodeling (OR: 0.15; 95% CI: 0.06 to 0.36)., Conclusions: The presence of LGE on CMR substantially worsens prognosis for adverse cardiovascular events in DCM patients, and the absence indicates left ventricular reverse remodeling., (Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Aims: The pathophysiology underlying aortic valve stenosis (AVS)-induced cardiac dysfunction and reduced exercise capacity is unclear. We hypothesize that improvement of myocardial external efficiency (MEE)--the ratio between external work and myocardial oxygen consumption (MVO2)--underlies functional improvement of AVS patients after aortic valve replacement (AVR). Therefore, the aim of this proof-of-concept study was to investigate whether myocardial efficiency is reduced in patients with cardiac hypertrophy caused by AVS and to assess the effect of AVR on myocardial efficiency in relation to exercise capacity., Methods and Results: Echocardiography, cardiopulmonary exercise test, [(11)C]-acetate positron emission tomography and cardiovascular magnetic resonance imaging were performed in 10 AVS patients prior to (pre-AVR) and 4 months after AVR (post-AVR). Fourteen healthy individuals served as control group. MEE was significantly lower in pre-AVR patients (32 ± 7%) than in controls (49 ± 6%). AVR significantly decreased left ventricle mass and MVO2. Also, external work significantly decreased post-AVR reaching similar values as in controls. AVR significantly improved MEE from 32 ± 7 to 37 ± 5% (P = 0.02). Moreover, significant correlations were present between the AVR-induced increase in MEE and changes in both exercise work (r = 0.74, P = 0.01) and peak VO2 (r = 0.67, P = 0.03). However, four AVS patients did not show improved MEE, which was associated with no or minimal improvement in exercise parameters., Conclusion: MEE is significantly reduced in patients with AVS-induced hypertrophy. Improved MEE is an important predictor of AVR-induced improvement of exercise capacity in AVS patients. Future investigation is needed to confirm our observations in a large prospective, multicenter clinical trial., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.)

Purpose: Next to hypertrophy, hypertrophic cardiomyopathy (HCM) is characterized by alterations in myocardial energetics. A small number of studies have shown that myocardial external efficiency (MEE), defined by external work (EW) in relation to myocardial oxidative metabolism (MVO(2)), is reduced. The present study was conducted to identify determinants of MEE in patients with HCM by use of dynamic positron emission tomography (PET) and cardiovascular magnetic resonance imaging (CMR)., Methods: Twenty patients with HCM (12 men, mean age: 55.2 + or - 13.9 years) and 11 healthy controls (7 men, mean age: 48.1 + or - 10 years) were studied with [(11)C]acetate PET to assess MVO(2). CMR was performed to determine left ventricular (LV) volumes and mass (LVM). Univariate and multivariate analyses were employed to determine independent predictors of myocardial efficiency., Results: Between study groups, MVO(2) (controls: 0.12 + or - 0.04 ml x min(-1) x g(-1), HCM: 0.13 + or - 0.05 ml x min(-1) x g(-1), p = 0.64) and EW (controls: 9,139 + or - 2,484 mmHg x ml, HCM: 9,368 + or - 2,907 mmHg x ml, p = 0.83) were comparable, whereas LVM was significantly higher (controls: 99 + or - 21 g, HCM: 200 + or - 76 g, p < 0.001) and MEE was decreased in HCM patients (controls: 35 + or - 8%, HCM: 21 + or - 10%, p < 0.001). MEE was related to stroke volume (SV), LV outflow tract gradient, NH(2)-terminal pro-brain natriuretic peptide (NT-proBNP) and serum free fatty acid levels (all p < 0.05). Multivariate analysis revealed that SV (ss = 0.74, p < 0.001) and LVM (ss = -0.43, p = 0.013) were independently related to MEE., Conclusion: HCM is characterized by unaltered MVO(2), impaired EW generation per gram of myocardial tissue and subsequent deteriorated myocardial efficiency. Mechanical external efficiency could independently be predicted by SV and LVM.

Objectives: To compare regional left ventricular (LV) volume curves obtained with real time three-dimensional echocardiography (RT3DE) with two-dimensional circumferential strain curves obtained by MRI in cardiac resynchronization therapy candidates., Background: Several methods using either ultrasound or MRI are used to quantify mechanical dyssynchrony (MD). Theoretically, LV volume and circumferential strain seem related, since both measures are connected to the radius of the ventricle., Methods: In 21 patients with chronic heart failure, RT3DE and tagged MRI were performed subsequently. Regional LV volume was computed from the ultrasound images. From the MR images, regional circumferential strain was calculated. Cross-correlations with time lags of 1% of the cardiac cycle were performed to compare the curves in corresponding LV segments. Furthermore, peak septal to lateral (SL) delays were compared between modalities., Results: High correlations were found between the curves (r(2) = 0.65 +/- 0.19), but regional differences in time delay between modalities were observed. In the septum, the volume curve was earlier than the strain curve by 1.8 +/- 17.0 time-lags (n.s.), while in the lateral wall, the volume curve was earlier by 3.3 +/- 12.0 time-lags (P < 0.02). There was a non-significant difference between SL delays in the two modalities (volume: -1.0 +/- 8.6%, strain: 3.0 +/- 12.7%, P = 0.17, a positive sign indicates that the lateral wall is delayed)., Conclusions: High correlations were observed between both modalities, but regional differences in time-delay were found. This is possibly inherent to the method of echocardiographic volume calculation and hampers the comparison of both measures for the quantification of MD.

Right ventricular (RV) volume measurements with cardiovascular magnetic resonance (CMR) is considered the gold standard, but acquisition and analysis remain time-consuming. The aim of our study was therefore to investigate the accuracy and performance of a semi-quantitative assessment of RV function in CMR, compared to the standard quantitative approach. Seventy-five subjects with pulmonary hypertension (15), anterior myocardial infarction (15), inferior myocardial infarction (15), Brugada syndrome (15) and normal subjects (15) underwent cine CMR. RV end-systolic and end-diastolic volumes were determined to calculate RV ejection fraction (EF). Four-chamber cine images were used to measure tricuspid annular plane systolic excursion (TAPSE). RV fractional shortening (RVFS) was calculated by dividing TAPSE by the RV end-diastolic length. RV EF correlated significantly with TAPSE (r = 0.62, p < 0.01) and RVFS (r = 0.67, p < 0.01). Sensitivity to predict RV dysfunction was comparable between TAPSE and RVFS, with higher specificity for RVFS, but comparable areas under the ROC curve. Intra- and inter-observer variability of RV EF was better than TAPSE (3%/4% versus 7%/15%, respectively). For routine screening in clinical practice, TAPSE and RVFS seem reliable and easy methods to identify patients with RV dysfunction. The 3D volumetric approach is preferred to assess RV function for research purposes or to evaluate treatment response.

Background: The assessment of forward stroke volume (SV) using dynamic, first-pass cardiac positron emission tomography (PET) was shown to be feasible in a limited number of studies with small numbers of subjects. The aim of this study was to compare first-pass derived SV with cardiovascular magnetic resonance imaging (CMR)-obtained values in a larger population of subjects., Methods and Results: Fifty-nine subjects with varying degrees of cardiac function were studied. Stroke volume was assessed using oxygen-15-labeled water (H(2)(15)O) dynamic first-pass PET for both the right ventricle (RV) and left ventricle (LV), and compared with the findings of aorta velocity-encoded phase-contrast CMR. The PET-estimated SV was higher for the RV than for the LV (133 +/- 34 vs 116 +/- 31 mL, P < .01, +/- SD), and both were higher compared with values obtained by CMR (81 +/- 20 mL, both P < .01, +/- SD). Although significant, the correlations between PET and CMR were moderate for both the RV (r = 0.37, P < .01) and the LV (r = 0.40, P < .01, +/- SD). Bland-Altman analysis revealed a progressive overestimation with increasing SV measured in either ventricle., Conclusions: First-pass dynamic H(2)(15)O PET for the assessment of forward SV is feasible, although values are progressively overestimated with increasing SV, particularly when the RV is used, and correlations with aorta velocity-encoded phase-contrast CMR are moderate. These findings are probably protocol-dependent and warrant further study before the use of first-pass dynamic H(2)(15)O PET in clinical or research settings can be advocated.

Objective: We sought to assess mitral annular (MA) size and function in hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM) using real-time 3-dimensional (3D) echocardiography (RT3DE)., Methods: The study included 30 patients with HCM, 20 patients with DCM, and 30 control subjects. RT3DE measurements included end-systolic and end-diastolic MA area (MAA) (MAA(3D)), MA diameter(3D), MA fractional area change (MAFAC), and MA fractional shortening. In subgroup of 50 patients, magnetic resonance imaging (MRI) was used for MAA(MRI) and MA diameter(MRI) measurement., Results: End-diastolic MAA(3D) was larger in HCM than in control group (P < .0001). Higher MAFAC and MA fractional shortening were present in HCM than in control group (P = .001 and P = .006, respectively). End-systolic and end-diastolic MAA(3D) in DCM were higher than in HCM and control groups (P < .0001). Lower MAFAC and MA fractional shortening were present in DCM than in HCM and control groups (P < .0001). MAFAC correlated well with left ventricular function in control subjects (r = 0.94, P < .0001), whereas correlation was less in DCM (r = 0.53, P = .02) and HCM (r = 0.42, P < .01). RT3DE and MRI measurements were comparable., Conclusion: RT3DE assessment of MA size and function in control subjects and patients with cardiomyopathy is accurate and well correlated with MRI.

Accurate quantification and timing of regional myocardial function allows early identification of dysfunction, and therefore becomes increasingly important for clinical risk assessment, patient management, and evaluation of therapeutic efficacy. For this purpose, the application of tissue Doppler echocardiography has rapidly increased. However, echocardiography has some major inherent limitations. Cardiovascular magnetic resonance imaging with tissue tagging provides highly reproducible data on myocardial function, not only in longitudinal and radial directions, but also in the circumferential direction. Because of the development of faster imaging protocols, improved temporal resolution, less time-consuming postprocessing procedures, and the potential of quantifying myocardial deformation in 3 dimensions at any point in the heart, this technique may serve as an alternative for tissue Doppler echocardiography and is now ready for more widespread clinical use. This review discusses the clinical use of cardiovascular magnetic resonance tissue tagging for quantitative assessment of regional myocardial function, thereby underlining the specific features and emerging role of this technique.