Losartan improves diastolic ventricular filling of hypertensive patients with diastolic dysfunction.

To evaluate the role of losartan on left ventricular (LV) function of hypertensive patients. Hypertensive patients (n = 19) underwent evaluation of systolic and diastolic LV function, using radionuclide ventriculography (RVG), before and at 3 mo into the treatment with the angiotensin II antagonist losartan. All patients underwent a baseline 12 lead ECG and an echocardiogram (ECHO), which was also repeated at 3 mo into treatment. Results are expressed as mean +/- SEM and statistics were performed using paired t-test. A p value < or = 0.05 was considered significant. Treatment with losartan for 3 mo had no effect on LV mass measured by echo (141+/-5 vs. 139+/-6 g/m2). The LV ejection fraction, measured by RVG, was unchanged by treatment when compared to the baseline study (58+/-2% vs. 57+/-2%, respectivelly, p = 0.49). Considering all patients involved in the study (n = 19), the LV "Peak Filling Rate" (PFR), a parameter of diastolic function measured by RVG, was also unchanged by treatment when compared to baseline (2.5+/-0.2 EDV/s vs. 2.5+/-0.3 EDV/s, respectively, p = 0.9). However the analysis of those patients with evidence of diastolic dysfunction (n = 12) on the baseline RVG (PFR < 2.5 EVD/s), demonstrated significant improvement of LV filling after therapy with losartan (PFR = 1.8+/-0.1 EDV/s vs. 2.3 +/-0.2 EDV/s, respectively, p = 0.05). This change was associated with improvement of symptoms. Our results demonstrated that hypertensive patients with diastolic dysfunction on radionuclide ventriculography have significant improvement of ventricular filling at 3 mo into treatment with losartan.

Echocardiographic analysis of regional and global left ventricular shape in Chagas' cardiomyopathy.

Chagas' heart disease is a common form of cardiomyopathy in Latin America and an important cause of cardiac morbidity and mortality there. Left ventricular (LV) apical aneurysm and LV dysfunction are frequent findings in Chagas' cardiomyopathy. Because cardiac shape has important implications for LV function, we sought to characterize regional and global changes in LV geometry in Chagas' heart disease. Quantitative shape analysis was performed on 2-dimensional echocardiograms from 43 patients with Chagas' cardiomyopathy. Regional shape was quantitated by measuring endocardial curvature and global shape was evaluated by Fourier shape analysis of the endocardial contour. Data from 22 age- and sex-matched normal test subjects were used for comparison. Regional shape analysis demonstrated decreased apical curvature (consistent with blunting of normal apical shape) in the group with Chagas' disease compared with controls (apical 2-chamber view: 19 +/- 1 vs 24 +/- 1 [p = 0.0039] at end-diastole and 20 +/- 2 vs 29 +/- 3 [p = 0.0019] at end-systole). Fourier shape power index was decreased in the Chagas' group, consistent with a more spherical ventricle (apical 2-chamber view: 9 +/- 1 vs 17 +/- 2 [p <0.0001] at end-diastole and 12 +/- 1 vs 35 +/- 3 [p <0.0001] at end-systole). Shape changes among the population with Chagas' disease were further evaluated in those with end-diastolic volumes equal to or greater than the median for the group (104 ml) and those < 104 ml. Global shape did not differ between patients with dilated ventricles and those with relatively nondilated ventricles. Diastolic Fourier shape power index = 8 +/- 2 in dilated ventricles compared with 9 +/- 5 in nondilated ventricles (p = 0.53); systolic Fourier shape power index = 10 +/- 2 in dilated versus 14 +/- 2 in nondilated ventricles (p = 0.15) (apical 2-chamber view). In Chagas' cardiomyopathy, LV apical deformation results in disruption of the optimal global prolate-ellipsoid shape, even in patients with relatively preserved LV volumes.

Amplitude information from Doppler color flow mapping systems: a preliminary study of the power mode.

The flow of a saline-glycerin solution with sand particles through a continuous in vitro flow system was imaged by using two commercially available Doppler color flow mapping systems in a power mode (Toshiba SSH-160A and Advanced Technology Laboratories [ATL] Ultramark 9). The images generated from seven solutions with particle concentrations ranging from 0.0001 x 10(12) to 6 x 10(12) particles/liter and a mean velocity of 30 cm/s measured with use of pulsed Doppler ultrasound were used to examine the dependence of the power mode on particle concentration. To examine the velocity dependence, 20 mean velocities ranging from 0.1 to 0.53 m/s (3 to 30 liters/min) and three particle concentrations (1, 3 and 6 x 10(12) particles/liter) in the solution were used. The recorded images were digitized and analyzed off-line. The SUM values, or the adjusted color intensity levels in delineated areas of interest in the displayed flow, were compared. In general, the power mode was sensitive in displaying slower velocity flows; in the selected particle concentration and velocity ranges, it was both velocity and concentration dependent. The specific dependence differed for the two color flow mapping systems.

Value and limitations of color Doppler echocardiography in the evaluation of percutaneous balloon mitral valvuloplasty for isolated mitral stenosis.

The limitations of 2-dimensional and pulsed Doppler echocardiography in patients undergoing mitral valvuloplasty are well known. This study was undertaken to assess the value of color Doppler flow imaging in 36 symptomatic mitral stenosis patients who subsequently underwent successful balloon mitral valvuloplasty by comparing the results to those obtained at cardiac catheterization. Color Doppler-guided conventional Doppler assessment agreed well with cardiac catheterization results in classifying mitral stenosis as mild, moderately severe and severe, both before and after valvuloplasty. Color Doppler was also useful in identifying patients who had moderate to severe mitral regurgitation before and after valvuloplasty. Color Doppler flow mapping was more sensitive than oximetry in the detection of iatrogenic atrial septal defects, which were noted in 25 patients. The defects of those patients with smaller defects by color Doppler (diameter less than 0.7 cm) or echocardiographic shunt volume less than 0.7 liters/min tended to close, usually within 6 months, as opposed to those with larger defects or higher shunt volumes, which tended to persist. Echocardiographic shunt volumes revealed a fair correlation with oximetric results.