In this article we describe three patients in whom biplane transesophageal echocardiography was useful in diagnosing sinus venosus type atrial septal defects. In two patients, diagnosis of anomalous pulmonary venous drainage was made correctly by biplane transesophageal echocardiography.

Adolescent↗

PubMedDate not supplied

Relationship between mitral regurgitation and left ventricular outflow obstruction in hypertrophic cardiomyopathy.

To clarify the relationship between mitral regurgitation and left ventricular outflow obstruction, Doppler and two-dimensional echocardiographic studies were performed in 62 patients with hypertrophic cardiomyopathy (22 with and 40 without obstruction caused by mitral systolic anterior motion with septal contact). Pulsed Doppler echocardiography with color Doppler flow imaging demostrated that in 20 of the 22 patients with obstruction, mitral regurgitation occurred mainly during midsystole from the onset to the end of mitral-septal contact. Such midsystolic mitral regurgitation was not observed in patients without obstruction, except in three of 25 patients with mild mitral systolic anterior motion without septal contact. Furthermore, that regurgitation developed or disappeared together with the obstruction during follow-up periods or pharmacologic interventions. Two-dimensional echocardiography showed that in 21 of the 22 patients with obstruction, a distal residual portion of the "anterior" mitral leaflet moved anteriorly in early systole and protruded into the outflow tract during midsystole to cause the obstruction. In the other patient with obstruction, who had only early systolic mitral regurgitation, a distal residual "posterior" leaflet moved similary. These results may indicate that the midsystolic mitral regurgitation is hydrodynamically induced by the midsystolic pressure gradient across the protruding distal residual anterior mitral leaflet.

Adult↗

PubMedDate not supplied

Quantification of mitral flow by Doppler color flow mapping.

This study was performed to develop and validate Doppler color flow methods for quantifying forward transmitral flow rates and volumes with isovelocity aliasing contours. We undertook computer modeling of flows and studied an animal model with strictly controlled mitral flows. Finite element analysis was first used to establish the isovelocity surface contours reconstructed from the magnitudes and directions of the velocity vectors proximal to the normal mitral orifice. We modeled finite element-simulated Doppler color flow isovelocity surfaces and computed non-angle-dependent simulated isovelocities to compare them. Then 24 pharmacologically induced hemodynamic states in six sheep in which mitral regurgitation had been previously created surgically were studied. Three methods were used for peak flow (PF) computation: (1) the classic hemispheric methods: PF = 2 pi r2.aliasing velocity; (2) a modified hemispheric method: PF = 2 pi r2.aliasing velocity Vo/Vo-aliasing velocity; and (3) a new segment of sphere method: PF = pi p2.aliasing velocity, where p is the chord from the zenith of the first aliasing contour to the circumference at its base. Mean volume flow was also calculated in combination with phasic flow information from continuous-wave Doppler echocardiography: mean volume flow = PF.VTI/Vmax.heart rate, where VTI and Vmax are the velocity-time integral and maximal velocity of mitral inflow by continuous-wave Doppler echocardiography. Compared with the flow rates obtained by electromagnetic flowmeters, different correlations and agreements were achieved for these methods. Correlation (r = 0.86) and agreement were best for the segment of sphere method for computation of forward mean volume flows in our model. Color flow Doppler quantitation with a segment of sphere or modified hemispheric method appears applicable for quantification of forward transmitral valve flow rates and volumes with reasonable accuracy.

Animals↗

PubMedDate not supplied

The present status of Pneumocystis carinii pneumonia in Japan with special reference to AIDS.

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Acquired Immunodeficiency Syndrome↗