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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 © 2011 Elsevier Ireland Ltd. All rights reserved.)

Purpose: To evaluate the influence of the osmotic pressure of solutions used for reconstituting the ultrasound contrast agent "Levovist" on the degree of video intensity of the enhancement and video intensity decay in contrast echocardiogram, we used 6 solutions with different osmotic pressures in both vitro and in vivo experiments., Materials and Methods: In the in vitro experiments, Levovist was reconstituted with 6 kinds of solutions with different osmotic pressures (Lactate Ringer's solution, 2.5%, 5%, 7.5%, and 20% glucose and distilled water) and peak video intensities and video intensity decay were measured. In the in vivo experiments, contrast echocardiography was performed in 7 adult volunteers, following the intravenous injections of Levovist, previously reconstituted with one of 2 solutions (5% glucose or distilled water)., Results: In vitro, at peak time, Levovist reconstituted with either Lactate Ringer's solution, 2.5% glucose, 5% glucose, or distilled water had good peak video intensities. At 30 s after peak time, Levovist reconstituted with Lactate Ringer's solution had greater enhancement and less decay than the other 5 solutions (P<0.001). In vivo, at 180 heart beats after peak time, the video intensity decay with 5% glucose was greater than that with distilled water (150+/-13 dB, 123+/-25 dB, respectively, P<0.05)., Conclusion: In this study, among various (2.5-20%) glucose solutions, the stability of the microbubbles differed, depending on the degree of osmotic pressure of the respective solutions; 5% glucose was the best. However, overall, the most suitable solution for reconstituting Levovist, was Lactate Ringer's solution. These findings could lead to effective strategies for better contrast echocardiography using Levovist by changing the current solution of choice to Lactate Ringer's solution or 5% glucose.

Abstract: Purpose: To evaluate efficacy and reproducibility of 320-slice computed tomography (CT) for measuring left atrial (LA) maximum (LAVmax) and minimum volume (LAVmin) during the cardiac cycle, we compared CT with three- and two-dimensional (3D and 2D) transthoracic echocardiogram (TTE). Materials and methods: LAVmax and LAVmin (ml), and LA ejection fraction (LAEF) (%) were assessed in 22 consecutive subjects (15 males, 59.5±15.1years) using retrospective electrocardiogram gated 320-slice CT (Aquilion One, Toshiba Medical) and 3D-TTE (IE-33, Phillips). LAVmax and LAVmin were selected from the time volume curve. LAEF was calculated as (LAVmax−LAVmin)/LAVmax×100(%). Results: Mean±standard deviation (SD) of LAVmax and LAV min were significantly larger by CT than 3D-TTE or 2D-TTE (both P<0.01). LAEF was 25.3±13.1% by CT, 30.2±6.8% by 3D-TTE (P=NS) and 33.9±8.9% by 2D-TTE (P<0.05). The correlation coefficients (CCs) between CT and 3D-TTE in LAVmax, LAmin, and LAEF were 0.64, 0.68 and 0.57, respectively. Mean difference±1.96SD of LAVmax, LAVmin and LAEF by Bland and Altman analysis calculated from CT minus 3D-TTE were 48.8±59.1ml, 41.1±63.2ml, and −4.9±21.1%, respectively. The CCs and mean difference±1.96SD between CT and 2D-TTE had similar tendencies. The CCs of interobserver variation were (for CT, 3D-TTE, 2D-TTE, respectively): 0.90, 0.95 and 0.94 (LAVmax), 0.97 and 0.97 and 0.93 (LAVmin), and 0.64, 0.77 and 0.34 (LAEF). Conclusions: 320-slice CT enables direct LAV measurements and has high reproducibility and positive correlation with 3D and 2D TTE. Absolute value of LAV by CT was larger than that by 3D and 2D TTE. [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]