Left ventricular thrombus and systemic emboli complicating the cardiomyopathy of Duchenne's muscular dystrophy.

A 17-year-old boy with Duchenne's muscular dystrophy and congestive cardiomyopathy with a left ventricular thrombus is described. The patient presented with flank pain, and computed tomography of the abdomen revealed multiple bilateral renal infarcts. An echocardiogram delineated a left ventricular thrombus and generalized hypokinesis with a left ventricular ejection fraction of 25%. Heparin therapy was started, but the patient died of refractory congestive heart failure. Autopsy revealed diffuse skeletal myopathy consistent with Duchenne's muscular dystrophy as well as biventricular cardiomyopathy with a recent left ventricular apical-septal mural thrombus. Right atrial thrombus, a left upper lobe pulmonary embolus, and splenic and renal infarcts were also noted. To our knowledge, this is the first reported case of left ventricular thrombus with or without systemic emboli in the cardiomyopathy of Duchenne's muscular dystrophy.

Echocardiographic evaluation of cardiac abnormalities in Duchenne's dystrophy and myotonic muscular dystrophy.

Routine echocardiographic examinations were performed on 53 individuals with muscular dystrophy (29 with myotonic muscular dystrophy [MMD] and 24 with Duchenne's dystrophy [DD]). Five of 29 (17%) with MMD and six of 24 (25%) with DD had typical mitral valve prolapse evidenced by echocardiography. All patients with DD and mitral valve prolapse had severe thoracic skeletal deformities, while none with MMD and mitral valve prolapse had such abnormalities. Other echocardiographic parameters analyzed included the fractional shortening of the left ventricle (% delta S), excursions of the left ventricular posterior wall (LVPW) and the ventricular septum, pre-ejection period/left ventricular ejection time ratios (PEP/LVET), and thickness of the LVPW and ventricular septum. Abnormal prolongation of the PEP/LVET ratio and increased thicknesses of the LVPW and ventricular septum were noted in some individuals in the MMD group. Decreased % delta S with diminished excursion and diastolic velocity of the LVPW were noted in some with DD.

Bilateral atrial myxomas. Echocardiographic considerations.

In this report we describe a patient with bilateral atrial myxomas, which were diagnosed preoperatively by echocardiography and angiography, and successfully removed. The excised tumor mass consisted of mobile right and left atrial myxomas connected by a common stalk which passed through the atrial septum, collectively resembling the shape of a dumbbell. Preoperative echocardiographic and angiographic observations were instrumental in planning the surgical approach, and correlated well with intraoperative findings and with the anatomic configuration of the intact pathologic specimen. Diagnostic aspects of echocardiography are emphasized as they relate to both isolated and bilaterally-occurring atrial myxomas.

Automated water-path ultrasonic examination of scrotum.

A new method of examining the scrotum by ultrasound with an automated water-path scanner is described. This method allows immobility of the scrotum in a more acceptable and painless way than in contact scanning methods. Panoramic scans of the entire scrotum and precision tomographic plane placement are advantages over conventional techniques. A description of normal scrotal anatomy includes the mediastinum of the testis, an important scrotal landmark. Representative cases of benign and malignant scrotal disease are presented to emphasize the utility of water-path scanning.

CW and pulsed Doppler echocardiography utilizing a stand-alone system.

An independent directional Doppler system operating in pulsed or continuous-wave mode and a real-time spectral analyzer with a 3 ms temporal resolution have been used to supplement conventional real-time and M-mode echocardiography. Examination techniques as well as findings in normal and abnormal hearts are presented. Continuous-wave Doppler is most useful for detection of peak frequency shifts for calculation of valvular gradients while pulsed Doppler is superior in the detection of small jets of abnormal flow and in display of spectral broadening. Real-time spectral analysis allows interactive selection of peak frequency shifts, can separate coincident flows by signal intensity and depicts high frequency valvular movements to rival the capabilities of M-mode.

Doppler ultrasound in aortic stenosis: in vitro studies of pressure gradient determination.

Torricelli's equation expresses a simple relationship between fluid velocity and pressure gradient in orifice flow and is currently used in conjunction with noninvasive Doppler ultrasound to determine gradients in mitral stenosis, and aortic stenosis, as well as other cardiovascular orifices. In theory, however, the Torricelli equation overestimates the gradient in aortic stenosis and the Borda equation should be more applicable. A brief tutorial derivation of the Borda and Torricelli equations is presented. The applicability of Torricelli's equation in aortic stenosis was studied experimentally with a rigid wall, pulsatile flow analogue. Doppler ultrasound and manometric data were collected simultaneously. Percent stenosis, peak flow rate and fluid viscosity were varied. The results demonstrated that the Torricelli equation consistently overestimated the pressure gradient. At 61% area stenosis, the overestimation exceeded 100%. In vivo studies are required to determine the relevance of the observations to clinical situations.

Representations of rapidly oscillating structures on the Doppler display.

In cardiovascular applications of Doppler ultrasound, oscillating structures are at times within the sample volume of the transducer. When the period of oscillation is shorter than the time window of the Fourier transform, the velocities of the structure are not resolved in time by the frequency analyzer. The resulting display can differ considerably from that obtained from structures with linear velocities. The investigation characterizes this phenomenon with the use of theoretical relations, mechanical model experiments and patient data. The results demonstrate that the representations of rapidly oscillating structures on the Doppler display can be interpreted in terms of frequency of oscillation and also, to some extent, in terms of maximum displacement of the structure.

Doppler ultrasound in orifice flow. In vitro studies of the relationship between pressure difference and fluid velocity.

The validity of an orifice equation (Torricelli's law) which expresses a simple relationship between the pressure difference across an orifice and the maximum fluid velocity in the orifice was tested in vitro. An aqueous suspension of barium sulfate particles with a polymer added to attain variations in viscosity, was forced through orifices which ranged in diameter from 0.4 to 4.7 mm. The pressure difference across the orifice was determined with a transducer and the maximum fluid velocity in the orifice was determined with Doppler ultrasound. Tests were performed at Reynolds numbers, fluid viscosities, and pressure differences that spanned the following ranges: 400-25,000, 1-5 cP, and 3-100 mmHg, respectively. At pressure differences larger than 3 mmHg and fluid viscosity 3 cP (approximate viscosity of in vivo blood), Torricelli's law was demonstrated to be valid for orifice diameters larger than 1.6 mm. The validity of the law was found to be relatively insensitive to variations in orifice length.