The E(es) can be reliably estimated from simple noninvasive measurements. This approach should broaden the clinical applicability of this useful parameter for assessing systolic function, therapeutic response and ventricular-arterial interaction.

Background-Diffusion tensor magnetic resonance imaging (DT-MRI) provides a means for nondestructive characterization of myocardial architecture. We used DT-MRI to investigate changes in direction-dependent water diffusivity to reflect alterations in tissue integrity (trace apparent diffusion coefficients [ADCs] and fractional anisotropy [FA]), as well as indicators of remodeling of fiber helix angles, in patients after myocardial infarction. Methods and Results-Thirty-seven patients (35 men, 2 women; median age, 59) after acute myocardial infarction (median interval from onset, 26 days) were enrolled. DT-MRI was performed at the midventricular level to measure trace ADC, FA, and helix angles of myofibers. Helix angles were grouped into left-handed helical fibers, circumferential fibers, and right-handed helical fibers. Measurements were correlated with viability and regional wall motion assessed by contrast-delay-enhancement and cine MRI, respectively. The infarct zone showed significantly increased trace ADC and decreased FA than the remote zone.

Background-We used diffusion-tensor cardiac MR to investigate myocardial microstructure changes, including tissue integrity (mean diffusivity [MD], fractional anisotropy) and fiber architecture (helix angles) in patients with recent myocardial infarction (MI). This study aimed to investigate the sequential changes of myocardial microstructure and its relationships with changes of macrostructure and function of the left ventricle post-MI. Methods and Results-Seventeen patients (age, 55.1Ϯ11.5 years; all men) participated in the follow-up study.Diffusion-tensor cardiac MR, cine gradient echo for left ventricle function, and late gadolinium enhancement for viability were measured from recent to chronic MI (median interval, 191 days). When compared with the remote zone, the infarct-adjacent zone showed overall increase of MD (2-way MANOVA, F 1,16 ϭ36.3; PϽ0.001), decrease of fractional anisotropy (F 1,16 ϭ5.8; Pϭ0.029), and decrease of mean helix angles (F 1,16 ϭ62.0; PϽ0.001). From recent to chronic MI, there was overall sequential decrease of MD (F 1,16 ϭ22.6; PϽ0.001) and increase of fractional anisotropy (F 1,16 ϭ7.8; Pϭ0.013). Multiple linear regression showed that the improvement of wall thickening in the infarct-adjacent zone correlated with sequential decrease of MD in the infarct-adjacent zone (rϭϪ0.70; Pϭ0.002) and increase of mean helix angles (ie, more right-handed helical myofiber reorientation, predominantly subendocardial location) in the remote zone (rϭ0.60; Pϭ0.011). Likewise, wall thickening in the remote zone correlated with MD in the remote zone (rϭϪ0.72; Pϭ0.001) and mean helix angles in the infarct-adjacent zone (rϭ0.72; Pϭ0.001). Key Words: imaging Ⅲ magnetic resonance imaging Ⅲ myocardial infarction Ⅲ remodeling P ostinfarction late remodeling involves the left ventricle (LV) globally and is associated with time-dependent dilatation, distortion of ventricular shape, rearrangement of fiber architecture, and mural hypertrophy. 1 Clearly, there is a great need for, and utility in, the in vivo acquisition of a wealth of cardiac microstructures such as geometry, fiber and sheet orientation, and cell populations to improve our ability to design strategies for effective restoration of myocardium postinfarction. 2,3 Conclusion-Diffusion-tensor Editorial see p 4 Clinical Perspective see p 40Recently, diffusion-tensor cardiac MR (DT-CMR) has emerged as a unique method for the nondestructive reconstruction of the fiber structure of the LV, which has been validated to have strong correspondence with fiber orientation by histological correlation 4 -6 and also has been modified to advance its Received March 11, 2008; accepted November 6, 2008. application to the living human heart. 7-10 In a previous report, we used DT-CMR to observe the alteration of tissue integrity, indicated by mean diffusivity (MD, also known as traceapparent diffusion coefficient), fractional anisotropy (FA), and fiber architecture, indicated by helix angles (HA), in patients post-myocardial infarction (MI) at a median interval...

IBPs are frequently observed at multidetector CT in patients with IMH. They may resolve over time or appear during follow-up. These findings are not associated with a poor prognosis, and IBPs should be distinguished from ulcerlike projections.

Both high cholesterol burden and vascular inflammation are not only associated with atherosclerosis, but also contribute to the development of arterial stiffness in FH patients. Early detection of hypercholesterolaemia in FH patients is warranted to prevent the untoward pathophysiologies.

The slope of the preload recruitable stroke work relationship (M(w)) is a highly linear, load-insensitive contractile index. To investigate whether M(w) can be determined from a single steady-state beat, 45 patients were studied during cardiac catheterization. Single-beat M(w) (SBM(w)) was calculated directly from the baseline stroke work and baseline left ventricular (LV) end-diastolic volume (EDV(B)), and the volume-axis intercept (V(w)) was estimated as k x EDV(B) + (k - 1) x LV(wall), where k is the ratio of the epicardial shell volumes corresponding to V(w) and EDV(B) and LV(wall) is the wall volume. The mean of individual k values was 0.72 +/- 0.04, which correlated with LV mass significantly (r = 0.60, P < 0.001). SBM(w) calculated from a constant k of 0.7 predicted M(w) well (r = 0.88, P < 0.0001), and the prediction improved slightly when k was estimated from individual LV mass (r = 0.93, P < 0.0001). Subgroup analyses revealed that the single-beat technique also worked in patients with small or large LV mass or volume or with regional wall motion abnormalities. The absolute change in SBM(w) after dobutamine infusion also correlated with that in M(w). In conclusion, M(w) can be estimated from a steady-state beat without alteration of preload.

Circulation Journal Official Journal of the Japanese Circulation Society http://www. j-circ.or.jp iastolic dysfunction has a significant impact on prognosis in a wide range of cardiac disorders. 1 Noninvasive methods of estimating left ventricular filling pressure (LVFP) are often helpful for diagnosing and treating diastolic heart failure. Some echocardiographic parameters associated with left ventricular (LV) diastolic function, such as mitral inflow velocities, deceleration time, and pulmonary venous flow velocities, are significantly influenced by preload. 2,3 Tissue Doppler imaging (TDI) is relatively preload independent, 4,5 and E/e' (the ratio of early diastolic mitral inflow velocity to early diastolic mitral annular velocity) has been proposed to provide a non-invasive measure of LVFP. 6 However, TDI was developed to assess regional function, 7-12 and its value for estimating global diastolic function in coronary artery disease (CAD) with regional function abnormalities is by implication limited. Thus, the application of E/e' for estimating LVFP might be more appropriate for patients with global LV dysfunction. Our previous report 13 indicated that left atrial (LA) distensibility correlates logarithmically with LVFP in patients with severe mitral regurgitation. It was the first comparative echocardiographic-catheterization study to demonstrate the correlation between a LA volume parameter and LVFP. We hypothesized that LA distensibility could become an indicator of global diastolic function and might be useful for assessing LVFP not only in patients with mitral regurgitation but also in those with stable angina. Thus, we analyzed the relationship between LA volume parameters and LVFP in CAD patients with stable angina and performed a head-to-head comparison of those 2 parameters (E/e' and LA volume parameter) for the accuracy of assessing LVFP Background: Although E/e' (the ratio of early diastolic mitral inflow velocity to early diastolic mitral annular velocity) is widely used to measure left ventricular filling pressure (LVFP), its accuracy is questionable in coronary artery disease patients.

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