[Supraventricular extrasystolic arrhythmia as the first sign of tuberous sclerosis: description of a case]

Tuberous sclerosis (TS) is a rare congenital disease characterized by proteiform symptoms that effect the skin and the central nervous system. Occasionally morphofunctional anomalies of other organs such as the kidneys, lungs and heart are present. The clinical picture of the illness varies among patients, and diagnosis is based primarily on cutaneous or nervous system manifestations. During the last ten years, however, some cases of prenatal diagnosis have been reported. The literature reports very few cases of tuberous sclerosis with arrhythmias as the initial symptom. The case described refers to a newborn who presented with supraventricular arrhythmias, refractory to the common antiarrhythmic drugs; a subsequent M-mode and two-dimensional echocardiogram showed a small roundish mass in connection with the chordae tendinae of the mitral valve (rhabdomyoma). We initially diagnosed TS based on the appearance of achromic smooth spots of the skin. The onset of convulsions and a CAT scan that identified numerous calcified endocerebral nodules confirmed the diagnosis of tuberous sclerosis.

Modification of the characteristics of regurgitant jets when impinging upon a surface: an in-vitro investigation using Doppler colour flow mapping

Free jets were compared in vitro by colour Doppler flow mapping with jets striking a flat and a hemispherical surface, located 3 and 6 cm from a circular orifice (5 mm in diameter). The angles of the impinging jets were 45 degrees and 90 degrees. Flow rates from 6-52 ml.s-1 were tested (pulsatile jets, 0.5 s duration). Free jet areas (21.7 +/- 9.6 cm2) were larger (P less than 0.01) than that of impinging jets (14.3 +/- 5.6 cm2). The distance of the target was a significant factor for reducing areas of striking jets (P less than 0.001). The angle of incidence of the striking jet and the shape of the target surface were not independent factors, but they were important when interacting with flow rate (P less than 0.001). The percentage of total jet area of impinging jets occupied by swirling flow was larger for targets located at 3 cm (P less than 0.01), for a 90 degrees angle of incidence (P less than 0.01), for a flat target surface (P less than 0.05). We conclude that jets visualized in vitro by colour Doppler flow mapping are significantly modified when impinging a surface, with the interplay of several factors. This can be of importance in clinical settings.

Relation between three-dimensional geometry of the inflow tract to the orifice and the area, shape, and velocity of regurgitant color Doppler jets: an in vitro study

The relation between three-dimensional geometry of the inflow tract to the orifice and the area, shape, and velocity of regurgitant jets was studied in a pulsatile in vitro color Doppler flow model. A 2.5 MHz transducer connected to a diagnostic ultrasound machine was placed in a water tank facing pulsatile jets (duration, 0.5 second) obtained by a calibrated injector. Flow rate from 6 to 52 ml/sec were tested through a 5 mm diameter circular orifice. Four different three-dimensional inflow tract geometries were compared: (A) sharp-edged, (B) Venturi (funnel), (C) converging conical, and (D) diverging conical. Mean velocities of jets were measured by continuous-wave Doppler echocardiography. Driving pressures were also measured by means of a fluid-filled catheter. Two observers independently digitized contours of maximal color jet areas by computer system from two separate sets of experiments. Results are given as the mean values of the four measurements for each parameter. Jet areas were correlated to flow rate, with no difference from A through D. The shape (eccentricity) of jets was different between A and B (p less than 0.05), between B and D (p less than 0.01), and between C and D (p less than 0.01). The shape of jets was correlated with flow rate, continuous-wave velocity, and pressure gradient in B, C, and D but not in A. Measured pressure gradients and estimated gradients by continuous-wave Doppler echocardiography were similarly correlated from A through D.(ABSTRACT TRUNCATED AT 250 WORDS)