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Abstract Background Regional right ventricular (RV) dysfunction is the hallmark of Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy (ARVD/C), but is currently only qualitatively evaluated in the clinical setting. Feature Tracking Cardiovascular Magnetic Resonance (FT-CMR) is a novel quantitative method that uses cine CMR to calculate strain values. However, most prior FT-CMR studies in ARVD/C have focused on global RV strain using different software methods, complicating implementation of FT-CMR in clinical practice. We aimed to assess the clinical value of global and regional strain using FT-CMR in ARVD/C and to determine differences between commercially available FT-CMR software packages. Methods We analyzed cine CMR images of 110 subjects (39 overt ARVD/C [mutation+/phenotype+], 40 preclinical ARVD/C [mutation+/phenotype-] and 31 control) for global and regional (subtricuspid, anterior, apical) RV strain in the horizontal longitudinal axis using four FT-CMR software methods (Multimodality Tissue Tracking, TomTec, Medis and Circle Cardiovascular Imaging). Intersoftware agreement was assessed using Bland Altman plots. Results For global strain, all methods showed reduced strain in overt ARVD/C patients compared to control subjects (p 0.275). For regional strain, overt ARVD/C patients showed reduced strain compared to control subjects in all segments which reached statistical significance in the subtricuspid region for all software methods (p

Purpose: To evaluate the regional left ventricular (LV) myocardial strain of early stage hypertrophic cardiomyopathy (HCM) patients by magnetic resonance (MR) tissue tracking.Materials and Methods: In all, 114 adult HCM patients classified as NYHA I or II and 32 healthy volunteers were enrolled and underwent 3.0T MR examination. Vertical 2-chamber long axis, horizontal 4-chamber, and short axis cine sequence as well as late gadolinium enhancement images (LGE) were scanned. The cardiac function, regional LV tissue tracking variables, end-diastolic wall thickness (EDTH), and LGE extent were measured.Results: In the HCM group, 38 were NYHA I and 76 were NYHA II. By regional analysis, peak strain (PS) and peak displacement (PD) with radial, circumferential direction of hypertrophic segments (n = 283) were significantly lower than nonhypertrophic segments (n = 1541) (all P < 0.05). Radial PS was significantly correlated with LVEDTH (r = -0.467, P < 0.0001). Radial PD was negatively associated with LVEDTH (r = -0.331, P < 0.0001). The PS and PD of all directions were decreased in segments with LGE (n = 723) compared with those without LGE (n = 1101) (all P < 0.05). In addition, radial PS and PD were negatively associated with LGE extent (radial PS, r = -0.441; radial PD, r = -0.274; both P < 0.0001). All strain parameters showed excellent inter- and intraobserver agreements.Conclusion: Decreased regional LV myocardial strain hypertrophic and fibrotic segments of early-stage HCM patients can be measured by MR tissue tracking based on routine cine images. Moreover, myocardial strain may decrease with the increasing of myocardial hypertrophy as well as fibrosis.Level Of Evidence: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2017;46:1368-1376. [ABSTRACT FROM AUTHOR]

Background: Regional right ventricular (RV) dysfunction is the hallmark of Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy (ARVD/C), but is currently only qualitatively evaluated in the clinical setting. Feature Tracking Cardiovascular Magnetic Resonance (FT-CMR) is a novel quantitative method that uses cine CMR to calculate strain values. However, most prior FT-CMR studies in ARVD/C have focused on global RV strain using different software methods, complicating implementation of FT-CMR in clinical practice. We aimed to assess the clinical value of global and regional strain using FT-CMR in ARVD/C and to determine differences between commercially available FT-CMR software packages. Methods: We analyzed cine CMR images of 110 subjects (39 overt ARVD/C [mutation+/phenotype+], 40 preclinical ARVD/C [mutation+/phenotype-] and 31 control) for global and regional (subtricuspid, anterior, apical) RV strain in the horizontal longitudinal axis using four FT-CMR software methods (Multimodality Tissue Tracking, TomTec, Medis and Circle Cardiovascular Imaging). Intersoftware agreement was assessed using Bland Altman plots. Results: For global strain, all methods showed reduced strain in overt ARVD/C patients compared to control subjects ( p < 0.041), whereas none distinguished preclinical from control subjects ( p > 0.275). For regional strain, overt ARVD/C patients showed reduced strain compared to control subjects in all segments which reached statistical significance in the subtricuspid region for all software methods ( p < 0.037), in the anterior wall for two methods ( p < 0.005) and in the apex for one method ( p = 0.012). Preclinical subjects showed abnormal subtricuspid strain compared to control subjects using one of the software methods ( p = 0.009). Agreement between software methods for absolute strain values was low (Intraclass Correlation Coefficient = 0.373). Conclusions: Despite large intersoftware variability of FT-CMR derived strain values, all four software methods distinguished overt ARVD/C patients from control subjects by both global and subtricuspid strain values. In the subtricuspid region, one software package distinguished preclinical from control subjects, suggesting the potential to identify early ARVD/C prior to overt disease expression. [ABSTRACT FROM AUTHOR]

Purpose: To develop feature tracking (FT) software to perform strain analysis on conventional (nontagged) cardiac magnetic resonance imaging (MRI) function images. With the advent of MRI-conditional pacemaker systems, effects of cardiac pacing on myocardial strain can be studied using MR. In this study the impact of pacing on left ventricular (LV) strain was investigated using MR-FT in patients with an MRI-conditional cardiac implantable electronic device (CIED).Materials and Methods: FT was performed on 32 1.5T MR studies (16 patients with an MRI-conditional CIED and 16 control patients with normal scans). Short- and long-axis steady state free precession (SSFP) cines were used for the FT analysis. Strain was assessed using CVI(42) software (Circle Cardiovascular Imaging, Alberta, Canada). In addition, the intra- and interobserver variability was determined using the intraclass correlation coefficient.Results: Of the 16 patients with an MRI-conditional CIED, five patients were paced during the MRI exam. Despite the occasional presence of susceptibility artifacts induced by the CIED, radial, circumferential, and longitudinal strain parameters could be derived for all patients. Peak radial strain and peak circumferential strain were reduced during pacing when compared to the control group; for radial strain: 20.1 ± 4.7% vs. 33.1 ± 6.9%, P < 0.001, and for circumferential strain -7.5 ± 3.5% vs. -14.9 ± 3.2%, P < 0.05. Peak strain parameters were reproducible on an intra- and interobserver level.Conclusion: MR-FT is feasible in patients with an MRI-conditional CIED and can be used to quantify regional wall motion. J. MAGN. RESON. IMAGING 2016;44:964-971. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To distinguish focal fibrotic and non-fibrotic lesions in left-ventricular myocardium (LVM) in hypertrophic-cardiomyopathy (HCM)-subjects, we compared myocardial regional peak-strain values using two-dimensional speckle-tracking transthoracic-echocardiography (TTE) in multislice computed-tomography (CT)-detected fibrotic, non-fibrotic and normal control lesions. Methods: Twenty subjects (10 consecutive HCM-subjects (8-males, mean 63.4-years), 10 healthy controls (5-males, mean 51.5-years)) underwent speckle-tracking TTE (iE-33), and analysis of regional peak-longitudinal (LS) and radial-strain (RS), and corresponding strain rates in each of 17 LVM segments (American-Heart-Association classification). In HCM-subjects, fibrotic lesions were identified by early-phase defective enhancement and late-phase abnormal enhancement by CT (Light-Speed-Ultra-16). Regional peak LS and RS at basal, mid and apical levels were measured in MSCT-detected fibrotic and non-fibrotic LVM lesions. Results: In 10 HCM subjects, 143 lesions (84.1%) yielded good tracking on TTE. Twenty lesions showed fibrotic changes in 5 subjects by CT. Regional peak-LS and RS absolute values were significantly lower in both fibrotic and non-fibrotic lesions in HCM subjects than in controls at basal, mid, apical levels (all P<0.05). While peak-LS (%) absolute values were significantly lower in fibrotic than non-fibrotic lesions at basal, mid and apical levels (all P<0.05), regional peak-RS absolute values were significantly lower only at mid levels. LS was a more sensitive indicator than the corresponding rate, with better reproducibility. Conclusions: In HCM, regional peak-LS was significantly lower in fibrotic than non-fibrotic lesions in LVM by CT. Regional peak-LS by speckle-tracking provides useful information noninvasively to distinguish fibrotic from non-fibrotic lesions in LVM in HCM and normal LVM in healthy controls. [Copyright &y& Elsevier]

Abstract: Purpose: To differentiate pseudodyskinesis (PD) of the inferior left ventricular (LV) wall from inferior myocardial infarction (IMI) noninvasively, we performed focal site evaluation using two-dimensional speckle tracking transthoracic echocardiography (TTE). Materials and methods: Speckle tracking TTE was carried out in 57 patients, with 19 subjects in each of three groups (Group A, suspected PD; Group B, LV IMI; and Group C, controls). Inferior wall PD was defined as follows: compression of the inferior LV wall by the diaphragm in the LV short axis view with a normal electrocardiogram and no evidence of previous ischemic events. Results: Respective values in Groups A–C for LV ejection fraction (EF) were 63.6±4.2%, 52.3±7.6%, and 61.5±3.8%, for inferior wall speckle tracking focal site evaluation peak radial strain of 30.0±14.3%, 7.5±7.1%, and 42.1±22.9%, for peak circumferential strain of 23.1±6.0%, 16.8±8.4%, and 22.7±7.1%, and for longitudinal strain in the mid-inferior wall of 18.4±3.4%, 11.4±4.0% and 15.8±5.9%. LVEF values were significantly lower in Group B than Groups A and C (P<0.001), as were those of radial, circumferential, and longitudinal strains (P<0.05). In receiver-operating characteristic analysis the optimal cut-off values with corresponding sensitivities and specificities for differentiation of PD from IMI were >19% with 84.2% and 94.7% for radial, >15% with 89.4% and 52.6% for circumferential, and >15% with 73.6% and 100% for longitudinal strain, respectively. Conclusions: Determination of regional strain from speckle tracking TTE, especially radial and longitudinal strains, can provide focal and quantitative noninvasive evaluation for distinguishing PD of the inferior wall from IMI. [Copyright &y& Elsevier]