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SUMMARY Pulsed Doppler echocardiography (PDE) is a technique for evaluating blood flow characteristics at specific locations within the heart and great vessels. Because this method assesses blood flow rather than cardiac structures, PDE complements the findings of CARDIAC ULTRASOUND has greatly enhanced our ability to define structural disorders in the heart and great vessels. While certain cardiac diseases lend themselves to firm diagnosis by M-mode echocardiography, many valvular and congenital disorders result in normal or nonspecific echocardiographic findings. In these disorders structural abnormalities clearly exist which cannot be evaluated with present echocardiographic techniques. A range-gated pulsed Doppler device has therefore been developed which can identify blood flow patterns at well-defined intracardiac locations.1 4 By demonstrating whether intracardiac flow is normal or pathologic, direct inference can be made as to what structural abnormality exists.The use of the pulsed Doppler device for the evaluation of murmurs has been previously described using an audible signal as the primary output for interpretation.1 This system however has recently been further improved by the introduction of a graphical recording method which increases ease of interpretation, provides a printed record of pulsed Doppler findings, and allows for more precise timing of blood flow events. It is the purpose of this paper to illustrate the applications of this graphic technique in identifying valvular abnormalities and septal defects. MethodsIn accordance with the Doppler theory, the frequencies of sound reflected from an object will be altered if that object is moving. This alteration is known as Doppler shift. Blood will reflect high frequency sound because it contains particulate matter -namely the blood cells. The pulsed Doppler device uses repetitive bursts, or pulses, of sound in the megaHertz range, much like traditional M-mode echocardiographic systems. While most ultrasonic waves are reflected from the various cardiac structures, a small amount is backscattered by the blood cells within the chambers themselves. These waves can be analyzed using a special Doppler shift detector system. If an ultrasonic beam is directed at a nonturbulent moving blood sample, the reflected sound waves will be of fairly uniform Doppler shift. By contrast sound waves reflected from a turbulent blood sample will show wide fluctuations in Doppler shift. 576M-mode echocardiography. A new on-line graphical method for displaying pulsed Doppler information provides 1) a printed, permanent record of flow information, 2) precise timing of blood flow events, and 3) information on the direction of flow in the heart and great vessels.

Sixty-five patients were studied for the presence of aortic insufficiency by auscultation, conventional M mode echocardiography (echo), range-gated pulse Doppler flowmeter (Doppler), and supravalvular aortic angiography. Aortic insufficiency was demonstrated angiographically in 49 patients, of which eight (16%) were missed by auscultation. Echo missed 20 (41%), and Doppler missed seven (14%). Only two (4%) were missed by auscultation and Doppler combined. All methods were highly specific, but the combination of auscultation and Doppler was the most sensitive noninvasive method for detecting aortic insufficiency.

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Mental health service delivery is both a health care and business arrangement, and is accordingly impacted by national changes in both areas. HMO mental health services in the current health reform zeitgeist are being called on to provide more efficient, comprehensive integrated care. A planning effort is presented which is organized around (1) a quality improvement effort aimed at understanding who are the "customers" (patient, medical community, mental health staff, and client employer) and what they need and (2) coordination and integration with the HMO larger organizational plan and efforts. The unique benefits of staff model HMOs are discussed relative to mental health service.