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An 8-year-old boy with scimitar syndrome, an accessory diaphragm and an absent right superior vena cava, underwent surgery on March 28, 1983. The scimitar vein was separated from an accessory diaphragm and cut just above the right diaphragm where the vein penetrated. The vein was re-implanted into the right lateral portion of the right atrium and a tunnel was made between the atrial septal defect created in the septum and the site of the implanted vein. The accessory diaphragm was not removed because of the lack of compression on the right lung. At cardiopulmonary bypass, venous cannulae were inserted into the persistent left superior vena cava and inferior vena cava. Because of the absence of the right superior vena cava, the right atrium was not fixed by both cavae so that there was difficulty in intracardiac maneuvers. The patient is doing well 32 months after this treatment.

Bitter thresholds of a total of 93 amino acids, peptides, and their derivatives were analyzed quantitatively by use of hydrophobicity parameters reported for amino acid side chains and those for the whole molecules estimated from partition coefficients obtained experimentally. We also explored the steric parameters that best explained the variation in the intensity of bitterness attributable to the molecular shape. The results showed that the total length along the zigzag peptide backbone chain of the molecule is an important factor. The bitterness of nonzwitterionic N-acyl and ester derivatives and that of neutral N-acyl ester derivatives were expressed by a single, common equation together with those of zwitterionic amino acids and peptides. Thus the interaction via the charge with the receptor site was probably not an indispensible factor for triggering of the bitter sensation. This study, together with earlier ones, may serve as a prototype of approaches toward unraveling structure-activity relationships of complex molecules like amino acids, peptides, and their derivatives that are of medicinal or agricultural importance.

The role of left ventricular (LV) relaxation in the determination of transmitral flow dynamics was studied with pulsed Doppler flowmetry and high fidelity tip manometry in various cardiac diseases. Study population consisted of 14 cardiac patients (pts) with sinus rhythm, including 4 pts with chest pain syndrome, 4 with myocardial infarction, 3 with effort angina and 3 with hypertrophic cardiomyopathy. The acceleration of early diastolic inflow velocity (AC), the peak of early diastolic inflow velocity (peak EFV ) and the deceleration after the peak (DC) were determined from the phasic transmitral flow pattern. Hemodynamic parameters, i.e., cardiac index, mean pulmonary wedge pressure (PWP), peak positive dP/dt and the time constant of isovolumic LV pressure decay (T) were measured during cardiac catheterization. Decreases in AC, peak EFV and DC were accompanied by prolongation of T with correlation coefficient of -.851 (p less than .001), -.808 (p less than .001) and -.697 (p less than .01), respectively, indicating that impaired LV relaxation slows down the early diastolic LV filling irrespective of underlying cardiac disease. LV filling pressure did not appear as a predominant factor affecting the early diastolic filling in the pts studied, as indicated by an insignificant correlation between any of these flow indices and PWP. Also, no significant relations were found between the flow indices and other hemodynamic parameters. These results indicate that LV relaxation plays a primary role in determining the extent of the early diastolic filling. Pulsed Doppler flowmetry provides a new approach to evaluate the impairment of LV relaxation noninvasively and sensitively in cardiac disease.

1) Intracardiac flows were investigated by bi-directional pulsed Doppler technique with a combined use of the two-dimensional echocardiography. The flow at sampling sites in the heat and great vessels were correctly identified on the two-dimensional echocardiograms. 2) Soundspectrographic analysis of the flow Doppler signals was useful in obtaining information about flow modes and in differentiating flow signals from those of valves. 3) In healthy subjects, intracardiac flow revealed a laminar mode. As a matter of interest, a flow toward the aorta, which is a cranially turned flow, was found at the center and at the outflow tract of the left ventricle from mid to late diastole. 4) In mitral stenosis, the central stream at the stenotic portion exhibited an almost laminar and rapid flow. A good coincidence in flow mode was observed between clinical cases of mitral stenosis and experimental stenosis. 5) Disturbed flows were observed in the following diseased conditions. The diastolic regurgitant flow in the left ventricular outflow tract and mitral inflow in aortic regurgitation, the regurgitant flow into the left atrium and the diastolic mitral inflow in mitral regurgitation, the ejection flow in hypertrophic cardiomyopathy with outflow tract obstruction, and the tricuspid inflow in atrial septal defect. 6) Mechanisms of intracardiac flow dynamics were also discussed.

We attempted to estimate transmitral pressure gradient and mitral valve area (MVA) noninvasively in mitral stenosis (MS) by a bi-directional pulsed Doppler flowmeter combined with an electronic two-dimensional echocardiograph. Eleven patients with MS in sinus rhythm were studied by cardiac catheterization. Fifteen healthy subjects (H) served as normal control. The pulsed Doppler flowmeter operated with a carrier frequency of 2.5 MHz, a pulse repetition rate of either 5 KHz or 10 KHz and a sample volume of 1 X 3 X 3 mm. The velocity of transmitral central flow was measured by this system, monitoring audible Doppler sounds and cardiac images which depict the anatomic location of the sampling site. The Doppler signal was analyzed by a sound spectrograph. In estimating the transmitral pressure gradient and MVA, we employed a Doppler parameter (half time) defined as the time for instantaneous maximal blood flow velocity to reduce to one-half from its rapid inflow peak, which is independent of the angle between the ultrasonic beam and blood flow. Transmitral pressure gradient (delta P100) was measured as the pressure gradient between either left atrial or pulmonary capillary pressure and left ventricular pressure at the point after 100 msec from the nadir of left ventricular early diastolic pressure [( LA or PC--LVDP]100). MVA was obtained using a Gorlin's formula. The transmitral blood flow velocity in both MS and healthy groups revealed a narrow frequency band pattern with two peaks, R and A, in diastole. The former peak occurred during rapid inflow phase and the latter following atrial contraction. In the healthy group, the descent rate of R wave was increased than that in the MS group. The square root of the pressure gradient also reduced linearly with transmitral flow velocity in the MS group. Thus in the MS group, the transmitral velocity was directly proportional to the square root of the pressure gradient as described by a Bernoulli theorem, and the half time was proportional to the transmitral velocity. The square of the half time (delta t2) was highly correlated with delta P100 (r = 0.97), and the inverse of the half time (delta t-1) was correlated with MVA (r = 0.76). There was no significant correlation between delta P100 and diastolic descent rate of anterior mitral leaflet (DDR). The present study indicates that the half time is useful in estimating transmitral pressure gradient and MVA in mitral stenosis.

Vertebral arteriovenous fistulas caused by insertion of percutaneous monitoring catheter through internal jugular vein are rare complications. This is a case report of a successful treatment by transcatheter embolization using spring occluder for the fistulas. Particular attention should be paid to the following: Normal basilar and contralateral vertebral arteriograms are prerequisites to this procedure in order to avoid its potential neurological hazards. For the complete elimination of the fistulas with retrograde filling, embolic material should be placed in the artery not only proximal but also distal to the fistulas opening.

In this study, transmitral flow velocity during the diastolic period was non-invasively measured to assess diastolic behavior of the left ventricle by pulsed Doppler flowmetry combined with electronic beam sector-scanning echocardiography. The velocity pattern was found to have 2 wave components: one appears in the early diastolic rapid filling phase (R wave) and the other in the late diastolic phase. The peak of the early diastolic inflow velocity (peak EFV), the deceleration rate of the R wave (DC), and the peak of the late diastolic inflow velocity (peak LFV) were compared in healthy subjects as the control, patients with hypertension, hypertrophic cardiomyopathy and definite old myocardial infarction. Normal peak EFV and DC, 61.3 +/- 6.7 cm/sec and 355 +/- 67 cm/sec2, respectively, were markedly reduced in patients with hypertension (50.0 +/- 10.0 cm/sec and 265 +/- 75 cm/sec2), hypertrophic cardiomyopathy (48.8 +/- 10.7 cm/sec and 205 +/- 78 cm/sec2), and myocardial infarction (46.1 +/- 12.0 cm/sec and 240 +/- 84 cm/sec2). Among all disease groups the DC was most significantly reduced in the hypertrophic cardiomyopathy groups. Normal peak LFV, 39.9 +/- 11.0 cm/sec, was significantly increased in patients with hypertension (54.3 +/- 10.7 cm/sec) and myocardial infarction (50.0 +/- 11.0 cm/sec), but not in patients with hypertrophic cardiomyopathy (42.0 +/- 8.4 cm/sec). The ratio peak LFV/peak EFV was significantly greater in all disease groups than in the normal group. These findings indicate that impaired early diastolic filling in all disease groups was compensated by enhanced atrial contraction in patients with hypertension and myocardial infarction, and by prolonged rapid filling in patients with hypertrophic cardiomyopathy. Left ventricular wall thickness was better correlated with DC in patients with hypertension (r = -0.76, p less than 0.01) than in patients in the other groups, which indicates that the left ventricular wall thickening is a more important factor in determining diastolic behavior of the ventricle in hypertension than in hypertrophic cardiomyopathy and myocardial infarction. Thus, the pulsed Doppler technique was proved to be useful in assessing ventricular diastolic events non-invasively.

Intracardiac flow dynamic alterations in patients (pts) with prosthetic mitral valve (PMV) were studied to assess prosthetic valve functions using pulsed Doppler technique and two-dimensional echocardiography. The study population consisted of 23 pts who underwent mitral valve replacement (11 with the Starr-Edwards disc valve, nine with the Björk-Shiley tilting disc valve, two with the Hancock porcine valve, and one with the homograft valve), 20 pts with mitral stenosis, and 17 control subjects (15 healthy persons and two with lone atrial fibrillation). All pts had a normal functioning PMV by clinical evaluation except for one patient with a dysfunctioning homograft valve, which was angiographically documented. Flow velocity patterns were obtained at various sites in the left ventricle (LV) and the left atrium (LA). Flow dynamic alterations in pts with PMV were evaluated from the half time of transmitral flow velocity descent in diastole, as an index of the atrioventricular pressure gradient, the extent of dispersion of Doppler frequency spectrum of intraventricular flow as an index of the degree of flow disturbances and the Doppler signals with broadening spectra indicating transvalvular regurgitant flow into the LA. The results were as follows: In pts with PMV, the velocity of transmitral flow decreased slowly and linearly throughout diastole. The half time was significantly prolonged for pts with PMV as compared with that for control subjects (272 + 94 ms [mean + SD] vs 79 + 15 ms, p less than .001), though it was shorter than that in pts with mitral stenosis (457 + 145 ms, p less than .001). In pts with PMV, the half time for pts with the Björk-Shiley valve was relatively short as compared with that for pts with other valve. Marked prolongation of the half time (483 ms) was observed in a patient with a dysfunctioning homograft valve. These findings indicate that any PMV is obstructive, even with normal valve function, as compared with healthy mitral valves and that the Björk-Shiley valve is superior to the other PMVs studied in regard to the pressure gradient across PMV. Diastolic flow velocity patterns in the LV were highly dependent on the type of PMV. Apparently, the flow characteristics in the LV were disturbed in every patient with PMV regardless of the type of PMV. The high pressure gradient across the PMV suggested by the prolonged half time in pts with PMV, may be partially caused by flow disturbances produced by PMV.(ABSTRACT TRUNCATED AT 400 WORDS)