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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.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).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 (P0.001). 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, P0.05).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.

Purpose Chronic pulmonary arterial thromboembolism (CPATE) often causes right ventricular (RV) pressure overload but the relationship between the degrees of CPATE and RV pressure overload is not clear. To quantify the degrees of CPATE and RV pressure overload, we performed multislice computed tomography (CT) and Tissue Doppler Imaging (TDI) and compared the two modalities. Materials and methods Sixteen consecutive subjects (4 men, 12 women; age 27–72 with proven CPATE underwent CT. The right vascular obstruction index (VOI), the left VOI, and the total VOI (TVOI) were determined using the scoring system of Qanadli. The early systolic myocardial velocity (Sw) and diastole myocardial velocity (Ew) at the tricuspid annulus and the early diastolic tricuspid inflow ( E ) were obtained by TDI in the apical four chamber view; RV systolic pressure (RVSP) was estimated by pressure gradient of tricuspid valve regurgitation. E /Ew was calculated as the parameter of RV diastolic function. Results The right VOI was 23±10%, the left VOI was 18±10%, and TVOI was 41±14%. The means with ranges of Sw, Ew, E /Ew, RVSP, and brain natriuretic peptide (BNP) were 10.7 (range 7.7–14.6) cm/s, 7.7 (range 4.2–10.6) cm/s, 5.0 (range 2.2–8.1), 55 (range 26–90) mm Hg, and 50.3 (range 12.2–165) pg/ml, respectively. The correlation coefficients between Sw, Ew, E /Ew, RVSP, and BNP and either larger of right or left side (LVOI) and TVOI were 0.041, −0.163 (Sw vs. LVOI, TVOI), −0.153, −0.232 (Ew vs. LVOI, TVOI), 0.145, 0.241 ( E /Ew vs. LVOI, TVOI), 0.255, 0.401 (RVSP vs. LVOI, TVOI), and 0.192, 0.170 (BNP vs. LVOI, TVOI), respectively. The correlation coefficient between RVSP and BNP was 0.390. Conclusions TVOI was better correlated with RVSP ( R =0.401) than the other parameters (Sw, Ew, E /Ew, and BNP), and this was similar to the degree that BNP was correlated with RVSP ( R =0.390). TVOI can be a better indicator of RVSP than LVOI. CT VOI may be a useful parameter to assess CPATE morphologically.

Cardiac amyloidosis is generally a progressive disease with a poor prognosis, so early diagnosis and appropriate treatments are important. Although cardiac amyloidosis can be diagnosed definitively by endomyocardial biopsy, non-invasive methods of diagnosis are desired because of a great risk in biopsy. In ECG-gated enhanced multislice computed tomography, not only clear images of the cardiac morphology but also the character of myocardium indicating fibrosis can be identified. We demonstrate two patients with cardiac amyloidosis who showed marked thickening of left ventricular wall with partial fibrotic changes by enhanced multislice computed tomography.

To evaluate left atrial (LA) function in subjects with early stage primary hypertension (HT) and without enlargement of LA, we used transthoracic echocardiogram and measured LA volumetric emptying fraction and compared the results with those in healthy volunteers.42 subjects with early stage primary HT (21 males, aged 61+/-12 years), within 1 year of HT diagnosis and starting initial treatment, were enrolled in the study. An additional inclusion criterion was normal sinus rhythm electrocardiogram without enlargement of LA. As the control group, 31 healthy volunteers with normal sinus rhythm electrocardiogram (13 male, aged 57+/-11 years) were enrolled. Maximum and minimum volume of LA (LAV max and min, respectively) were selected manually and visually in B mode images acquired from a four-chamber view from apex of left ventricle (LV) using a modified Simpson method, and the LA emptying fraction (LAEF) was calculated by the following formula: LAV min/LAV max x 100 (%).There were no significant differences in age, male:female ratio, end-diastolic and end-systolic LV diameter, LA maximum volume, LV ejection fraction and E/A in mitral annulus between the two groups. However, we found that end-diastolic inter-ventricular septum thickness and end-diastolic LV posterior wall thickness were significantly larger in the HT group in comparison with the control group (P0.01), but the HT group did not fit the classical criteria of LV myocardial hypertrophy. The systolic and diastolic blood pressure, the end-diastolic and end-systolic volume of LV, the total weight of LV myocardium and the LAEF were significantly higher in the HT group than in the control group (P0.05).In subjects with early stage primary HT with normal sinus rhythm, in spite of a normal LAV, the LAEF may increase. This increase of LAEF may be regarded as one of the compensatory reactions against preload to the left side of the heart and precedes the occurrence of LA enlargement.