The aim of this study was to determine the value of extracellular volume fraction (ECV) for the non-invasive assessment of diffuse myocardial fibrosis (MF) in different stages of systolic left ventricular (LV) dysfunction in dilated cardiomyopathy (DCM) in comparison with endomyocardial biopsy. Non-invasive ECV assessment using cardiovascular magnetic resonance (CMR) T1 mapping reflects diffuse MF in patients with severe DCM, but earlier stages of DCM with mild LV functional impairment have not been investigated yet. Forty-five subjects with mild functional impairment and LV dilation [‘early DCM’, ejection fraction (EF) 45–55%], 29 with LV dysfunction and volume dilatation (‘DCM’, EF <45%) and 56 healthy volunteers (controls) underwent standard CMR imaging, late gadolinium enhancement (LGE) and T1 mapping for the calculation of ECV. The collagen volume fraction (CVF) was quantified histologically from endomyocardial biopsies of 24 DCM patients out of the study cohort. The ECV between ‘early DCM’ (25 ± 4%), ‘DCM’ (27 ± 4%), and controls (23 ± 3; P < 0.05 for all) differed significantly. There was a weak inverse correlation between ECV and EF (r = −0.35; P < 0.01). A strong correlation between ECV and CVF could be detected (r = 0.85; P = 0.01). The cut-off value for ECV to differentiate between healthy myocardium and DCM was 26% (specificity 91.1%, sensitivity 62.1%, area under the curve 0.8, P < 0.0001). ECV is already elevated at early stages of functional impairment, whereby an overlap between early DCM and controls is present. But 31% of the early DCM patients had an ECV fraction above the mean ±2 SD ECV of controls. ECV measurement with CMR reflects myocardial collagen content in DCM. Therefore, CMR-based assessment of ECV may have the potential to serve as a non-invasive tool for the quantification of diffuse MF in order to monitor therapy response and aid risk stratification in different stages of DCM.

Background: Causative treatment of patients with wild-type transthyretin amyloid cardiomyopathy (wtATTR-CM) is lacking. Recent reports indicate the potential use of epigallocatechin-3-gallate (EGCG), the most abundant catechin in green tea, to inhibit amyloid fibril formation. We sought to investigate changes of cardiac function and morphology in patients with wtATTR-CM after consumption of green tea extract (GTE). Methods: Twenty-five male patients (71 [64; 80] years) with wtATTR-CM were submitted to clinical examination, echocardiography, cardiac magnetic resonance imaging (cMRI) (n=14), and laboratory testing before and after daily consumption of GTE capsules containing 600 mg epigallocatechin-3-gallate for at least 12 months. Results: A significant decrease of left ventricular (LV) myocardial mass by 6% (196 [100; 247] vs 180 [85; 237] g; P=0.03) by cMRI and total cholesterol by 8.4% (191 [118; 267] vs 173 [106; 287] mg/dL; P=0.006) was observed after a 1-year period of GTE consumption. LV ejection fraction by cMRI (53% [33%; 69%] vs 54% [28%; 71%]; P=0.75), LV wall thickness (17 [13; 21] vs 18 [14; 25] mm; P=0.1), and mitral annular plane systolic excursion (10 [5; 23] vs 8 [4; 13] mm; P=0.3) by echocardiography remained unchanged. Conclusion: This study supports LV mass stabilization in patients with wtATTR-CM consuming GTE potentially indicating amyloid fibril reduction.

Assessment of left ventricular (LV) systolic function plays a central role in cardiac imaging. Calculation of ejection fraction (EF) is the current method of choice; however, its limited intermodal comparability represents a major drawback. The assessment of myocardial mechanics by strain imaging may better reflect the complex myocardial contractility. We aimed to evaluate different methods for quantification of LV strain on global and regional levels with a focus on the new non-proprietary feature tracking (FT) algorithm. Measurements of LV deformation were performed by means of high-resolution two-dimensional (2D) speckle tracking echocardiography (STE) and compared with values obtained by 2D feature tracking echocardiography (FT-E) and feature tracking cardiac magnetic resonance imaging (FT-CMR). Assessments with echocardiography started within 30 min after CMR examination to minimize time-dependent variations in myocardial function. Forty-seven patients were included. Assessments by STE were −15.7 ± 5.0% for global longitudinal strain (GLS), −14.6 ± 4.5% for global circumferential strain (GCS), and 21.6 ± 13.3% for global radial strain (GRS), while values obtained with FT-E were −13.1 ± 4.0, −13.6 ± 4.0, 20.3 ± 9.5, and with FT-CMR −15.0 ± 4.0, −16.9 ± 5.4, and 35.0 ± 10.8, respectively. Linear regression and the Bland–Altman analysis showed the best intramodal association for STE GLS and FT-E GLS (r = 0.88, bias = −2.7%, LOA = ±4.7%). The correlation for GCS and GRS was weaker, and for regional strain was poor. In contrast to EF, GLS showed a better intermodal correlation between echocardiography and CMR (r = 0.81 by speckle tracking, r = 0.8 by FT, and r = 0.78 by EF). In our study, measurement of global longitudinal LV strain using the new FT algorithm with CMR and echocardiography was comparable with measurements obtained by high-resolution STE. Compared with echocardiographic EF determination, FT-E GLS shows a better reproducibility and a better intermodal agreement with CMR, representing a fair non-proprietary solution for this assessment. clinicaltrials.gov. Unique identifier: NCT01275963.