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C Tei

Publications and source records attributed to C Tei.

At least 109 records · Page 6Linked to original sources
PubMed1987

[Diastolic pulmonary forward flow associated with pulmonary regurgitation demonstrated by Doppler echocardiography].

To demonstrate diastolic pulmonary forward flow, pulsed and continuous wave Doppler echocardiograms were recorded in four patients with postoperative residual pulmonary stenosis and regurgitation (Group I). To clarify the mechanism, we further examined 24 patients with pulmonary regurgitation without diastolic pulmonary forward flow, including three patients with surgical correction of tetralogy of Fallot (Group IIa) and 21 patients with functional pulmonary regurgitation (Group IIb), and compared the peak velocity and pressure half time of pulmonary regurgitation among the three groups. Diastolic pulmonary forward flow was characterized as a flow signal which began after the abrupt cessation of pulmonary regurgitation and continued until the beginning of ejection flow. The onset of the flow coincided with that of premature opening of the pulmonary valve, and was following atrial contraction in one, before atrial contraction in two, and mid-diastolic in one. The velocity of diastolic pulmonary forward flow was increased during inspiration and its maximum velocity was 1.3 m/sec. Simultaneous recording of pressures and continuous wave Doppler echo performed in two patients in Group I showed the equalization of right ventricular and pulmonary artery pressures during the flow. There was no significant difference in the peak velocity of pulmonary regurgitation among the three groups of patients. The mean pressure half time was significantly shortened in patients in Group I (90 +/- 11 msec) compared with those in patients in Group IIa (143 +/- 40 msec, p less than 0.05) and Group IIb (310 +/- 71 msec, p less than 0.001). In conclusion, a diastolic pulmonary forward flow seems to be produced by the rapid equalization of right ventricular and pulmonary artery pressures due to severe pulmonary regurgitation in the face of decreased right ventricular compliance.

Adult↗
PubMed1987

[Incidence of tricuspid regurgitation in normal subjects according to a new Doppler echographic criterion].

To develop a Doppler echocardiographic criterion for tricuspid regurgitation (TR) and to determine the incidence of TR in normal subjects, we examined 357 apparently normal subjects ranging in age from five to 95 years using pulsed and continuous wave Doppler echocardiography. A Doppler transducer was placed over the right ventricular apex, with the Doppler beam directed parallel with TR flow. TR was judged to be present when a holosystolic abnormal flow pattern with the peak velocity greater than 1.5 m/sec was recorded at the tricuspid valve orifice. This was based on the theory that in TR systolic pressure gradient across the tricuspid valve should be 10 mmHg or greater in normal subjects. TR was detected in 87 (24%) of 357 subjects and the mean peak velocity of the TR was 2.1 +/- 0.2 m/sec (mean +/- SD). It was more frequent in women (28%) than in men (19%) and differed significantly among the young, middle and old age groups. It was 79% in the first decade, 30% in the second, 10% in the third, 21% in the fourth, 5% in the fifth, 19% in the sixth, 14% in the seventh, 23% in the eight, 37% in the ninth and 40% in the tenth. The minimum dimension of the tricuspid annulus was significantly enlarged (p less than 0.001) in subjects with TR (2.2 +/- 0.3 cm/m2) compared to that of subjects without TR (1.8 +/- 0.3 cm/m2).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1987

[Exercise capacity in ischemic heart disease evaluated by continuous wave Doppler echocardiography].

To evaluate exercise capacity in ischemic heart disease, we measured the peak aortic flow velocity by continuous wave Doppler (CWD) echo from the suprasternal notch at rest and during multiple load ergometer testing in the supine position. The study subjects consisted of 14 normal controls, 10 patients with effort angina and 21 patients with old myocardial infarction (OMI). In all the patients and in five normal subjects, thallium-201 emission CT (SPECT) was also performed immediately after exercise and four hours subsequently. Change in the peak aortic flow velocity during exercise was compared with the extent of perfusion defects and the presence or absence of redistribution images on SPECT. At rest, the peak aortic flow velocity was not different from that of the other three groups. During exercise, it increased progressively (crescendo type) as the exercise was increased in normal subjects. In patients with angina pectoris it increased at the initial stage of exercise, but was unchanged (crescendo-plateau type) or decreased (crescendo-decrescendo type) at the maximum exercise stage. Redistribution images on SPECT were seen in nine of 10 patients with angina pectoris. In patients with OMI, change in the peak aortic flow velocity was of the crescendo type in 14, crescendo-decrescendo in three and crescendo-plateau in one. In the remaining three it decreased from the beginning of exercise (decrescendo type). Redistribution images were seen in all patients with the crescendo-decrescendo, crescendo-plateau or decrescendo types. Furthermore, myocardial damage was much more extensive in the decrescendo type. We conclude that exercise continuous wave Doppler echocardiography is a useful means of evaluating exercise capacity in ischemic heart disease.

Adult↗
PubMed1986

Simplified echocardiographic measurement of the mitral anulus.

Postmortem, clinical, and experimental observations suggest an approximate elliptical shape for the mitral valve anulus, limiting the accuracy of single-diameter measurements in estimating annular area and circumference. A detailed method has been reported which uses six apical echocardiographic views at 30-degree rotational intervals to measure the mitral anulus, providing results comparable with pathologic and experimental reports. Annular data from nine normal subjects and 18 patients with dilated cardiomyopathy were analyzed to test a simplified measurement procedure. Assuming an elliptical shape, mitral annular area (MAA) and mitral annular circumference (MAC) were calculated by means of major (usually corresponding to the four-chamber view) and minor diameters from two orthogonal apical planes. Assuming a circular shape, MAA and MAC were also estimated by means of single annular diameters obtained from both an apical four-chamber and a parasternal long-axis view. Systolic and diastolic points were analyzed together, providing an n = 54 in the linear regressions. The two-plane results in MAA and MAC were nearly identical to those from the six-plane method, with very close correlation (r = 0.982 to 0.990). The single-plane results systematically overestimated MAA and MAC, with less correlation (apical, r = 0.943 to 0.963; parasternal, r = 0.852). Thus, while single-diameter measurements may correlate with global changes in annular size, the two-plane method represents a simplified but accurate method for estimating MAA and MAC in humans.

Echocardiography↗
PubMed1986

Asymmetric apical hypertrophy: ten years experience.

This paper reports 10 years experience of 31 patients with asymmetric apical hypertrophy, in whom left ventricular hypertrophy involved the apex exclusively and giant T wave inversion in the left precordial leads was the characteristic finding. This type of hypertrophic cardiomyopathy was observed predominantly in men over 40 years of age. Family history was negative and patients usually had no complaints. Left ventricular hypertrophy was evident by physical examination as in other forms of hypertrophic cardiomyopathy, but a systolic murmur was faint or absent and the second heart sound was frequently split. Electrocardiographic signs may fluctuate, and occasionally progression or regression occurs. Echocardiography including the two-dimensional method was essential for the diagnosis and left ventriculography was helpful for confirmation. To date complications have been infrequent and the prognosis seems good. The relation of asymmetric apical hypertrophy to other forms of hypertrophic cardiomyopathy is under investigation.

Adult↗
PubMed1986

[Continuous wave Doppler echocardiographic assessment of prosthetic aortic valves].

To assess the prosthetic aortic valve functions according to types and sizes of valves, the peak flow velocity was recorded by means of continuous wave Doppler echocardiography in 40 patients (age 45 +/- 15 years) with prosthetic aortic valves and in 25 normal subjects. Twenty-one patients had Björk-Shiley valves (1-18 months after replacement); 12 had St. Jude Medical valves (6-48 months after replacement); and seven had Carpentier-Edwards porcine xenografts (48-84 months after replacement). The peak blood flow velocity across the prosthetic valve was recorded at the left ventricular apex, the suprasternal notch, and the right parasternal border in the second intercostal space. The pressure gradient was derived from the peak flow velocity by means of the simplified Bernoulli equation (P = 4V2). The peak and mean flow velocities and the peak and mean pressure gradients were measured to evaluate the opening function of the prosthetic valves. The results were as follows; The peak flow velocities were recorded in 33 patients (83%) with aortic valve replacements. All four measurements were significantly greater in patients with prosthetic aortic valves than in normal subjects, but there was no significant difference according to the valve type. The opening function was less in patients with smaller valves than in those with larger ones. There was a clear correlation between opening function and valve size. We concluded that continuous wave Doppler echocardiography is a useful noninvasive method for evaluating the opening function of a prosthetic aortic valve.

Adult↗
PubMed1985

Paradoxical deterioration of left ventricular asynergy after administration of nitroglycerin.

The effects of nitroglycerin on segmental asynergy were studied by 2-dimensional echocardiography. Forty-five patients with coronary artery disease and segmental wall motion abnormality at rest were examined, 31 with Q-wave and 14 with only ST-T abnormalities. Left ventricular (LV) echocardiograms were recorded from the LV apex in 4 planes, obtained by systematically rotating the transducer at 45 degrees intervals around the mitral office, using a mechanical device. Sixteen LV segments were analyzed in each patient on real-time display by 2 observers independently. The wall motion analysis was classified as normal, hypokinetic, akinetic or dyskinetic. Of 720 segments, 596 were agreed on by 2 observers in the assessment of wall motion before and after administration of nitroglycerin: 334 segments (56%) showed no change in wall motion, 206 (35%) showed improvement of wall motion and 56 (9%) showed worsening of myocardial asynergy after nitroglycerin. These data suggest that administration of nitroglycerin may result in unexpected worsening of segmental asynergy. This may be secondary to an adverse effect of a decrease in perfusion pressure in critically occluded arteries or may represent a coronary steal phenomenon.

Aged↗
PubMed1985

Cardiac involvement in congenital myopathy.

We examined cardiac changes in 8 patients (4 men and 4 women, age 21-43 years) with congenital myopathy proven by skeletal muscle biopsy. Of 8 patients, 4 showed cardiac changes, including 1 with cytoplasmic body myopathy (patient 1), 2 with minimal change myopathy (patients 2 and 3) and 1 with nemaline myopathy (patient 4). Patients 1 and 2 showed left ventricular dilatation with severe global hypokinesis of left ventricular wall. These clinical features were quite similar to those of dilated cardiomyopathy and the patients were in NYHA class 3 or 4. Patient 3 had severe mitral regurgitation with mitral valve prolapse. This patient also had a persistent left superior vena cava and hypoplasia of the aorta, and her cardiac function was in NYHA class 3. Patient 4 showed moderate global left ventricular hypokinesis but the left ventricle was not dilated. This patient also had sino-atrial block and type A Wolff-Parkinson-White syndrome. His cardiac function was NYHA class 1. In conclusion, various types of congenital myopathy are associated with cardiac changes which can result in severe congestive heart failure.

Adult↗
PubMed1985

Clinical improvement in hypertrophic cardiomyopathy after inferior myocardial infarction.

In cases of hypertrophic cardiomyopathy, the pathophysiologic role of the systolic pressure gradient across the left ventricular outflow tract is the subject of continued controversy. A patient with this disorder is described whose symptoms and provokable intraventricular gradient disappeared after inferior myocardial infarction. Diastolic left ventricular pressures were essentially unchanged, the isovolumic relaxation period became prolonged and the ejection fraction decreased from 0.77 to 0.61 after infarction. The peak ejection rate was unchanged, but the disappearance of systolic anterior motion of the mitral valve leaflet and obstructive manifestations may have resulted from enlarged mid to late systolic ventricular volumes. This case suggests a direct relation between symptoms and intraventricular pressure gradient in certain patients with hypertrophic cardiomyopathy.

Blood Pressure↗
PubMed1985

Noninvasive pulsed Doppler echocardiographic detection of the direction of shunt flow in patients with atrial septal defect: usefulness of the right parasternal approach.

Noninvasive pulsed Doppler echocardiography combined with two-dimensional echocardiography by the right parasternal approach was performed to detect the shunt flow through the defect in 31 patients with suspected secundum atrial septal defect (ASD). A defect of the interatrial septum was seen on the two-dimensional echocardiograms of 30 of 31 patients. In all the 30 patients, Doppler signals of shunt flow could be recorded by placing the sample volume in the center of the defect on the two-dimensional echocardiogram. Neither a defect nor Doppler signal indicating shunt flow were demonstrated in any of 15 normal control subjects. Cardiac catheterization indicated significant shunt flow in all the 31 patients with suspected ASD. Doppler signals obtained from the center of the defect showed left-to-right and/or right-to-left shunt flow patterns. The direction of the shunt flow was mainly left to right, with its peak in late systole and atrial systole in 28 of 30 patients; mainly right-to-left flow was present in the remaining two patients, who had Eisenmenger's syndrome. The direction of flow as predicted by the Doppler signal was confirmed by the coincidence of direction of flow as seen on the contrast two-dimensional echocardiogram. In 22 patients for whom the measurement of the pulmonary-to-systemic flow ratio by oximetry was believed to be reasonably accurate, the ratio was fairly well correlated with Doppler-determined left-to-right shunt flow velocity (r = .71, SEE = 6.7 cm/sec).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1985

[Mechanism of systolic anterior motion of the mitral valve in dogs].

The mechanism of systolic anterior motion (SAM) of the mitral valve remains somewhat controversial. We previously reported that SAM can be produced in dogs using dobutamine infusion. In the present study, dobutamine infusion, dextran infusion and venesection were performed in 13 anesthetized closed-chest dogs to study the mechanism of SAM. The degree of SAM was determined by M-mode echocardiography. End-systolic and end-diastolic short-axis areas of the left ventricle at the level of the chordae tendineae and the fractional area changes were measured by two-dimensional echocardiography. SAM was produced in six of the 13 dogs during dobutamine infusions (Group 1), but not in the other seven dogs (Group 2). During dobutamine infusions, % fractional area changes were greater in Group 1 (85 +/- 5; mean +/- standard deviation) than in Group 2 (65 +/- 15) (p less than 0.01), and the end-systolic short-axis area of the left ventricle was smaller in Group 1 (0.7 +/- 0.4 cm2) than in Group 2 (1.9 +/- 0.3 cm2) (p less than 0.01), although no significant change was observed between Groups 1 and 2 in the end-diastolic short-axis area of the left ventricle. Subsequent injections of dextran (mean 340 ml) in Group 1, decreased the degree of SAM and increased the end-diastolic and end-systolic short-axis areas of the left ventricle. Subsequently, venesections (mean 400 ml) in Group 1 resulted in increases in the degrees of SAM and decreases in the end-diastolic and end-systolic short-axis areas of the left ventricle.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

[Continuous wave Doppler measurement of transmitral pressure gradients in mitral stenosis: comparisons with simultaneous catheterization measurements].

To determine the accuracy and reliability of measurements of mitral flow velocity and pressure gradients obtained from continuous wave Doppler (CWD) echocardiography, the left ventricular pressure, pulmonary capillary wedge pressure and CWD echo were simultaneously recorded simultaneously for 22 patients with mitral stenosis. An ultrasonic transducer was placed over the left ventricular apex to direct the ultrasonic beam parallel with the mitral flow. High-pitched audio signals were used to determine whether the ultrasonic beam direction was appropriate. The angle formed by the beam direction and the blood flow was assumed to be zero when a good Doppler echo was recorded. The maximum flow velocity and pressure gradients calculated from CWD echo were compared with pressure gradients obtained by catheterization. These were analyzed during the same heart beats. The results were as follows: Good recordings of pressures and CWD echograms were obtained for 17 patients, and their data were used for the analysis. The maximum flow velocity through the mitral valve obtained by CWD echography was very similar to the pressure gradients obtained by catheterization in terms of phases and patterns. The pressure gradients (x) calculated from CWD using a simplified Bernoulli's equation correlated well with those (y) measured at the same time on pressure tracings (y = 1.2x + 1.5, r = 0.92, p less than 0.001). Mean diastolic pressure gradients (X) obtained by CWD echography also correlated well with those (Y) recorded at catheterization (Y = 1.2X + 0.15, r = 0.95). Based on these results, we conclude that CWD echography is a reliable, noninvasive method to measure the pressure gradient across the mitral valve in patients with mitral stenosis.

Adult↗
PubMed1985

[Continuous wave Doppler assessment of prosthetic valves in the mitral position: comparison of the St. Jude medical mechanical valve and the porcine xenograft valve].

To assess the opening function of prosthetic valves in the mitral position with special reference to the type and size of the valve and the years since replacement, we recorded maximum flow velocity through the mitral orifice using continuous wave Doppler echocardiography for 50 patients with mitral valve replacement and 15 normal subjects. There were 33 patients with St. Jude Medical valves and 17 with porcine xenograft valves. An ultrasonic transducer was placed over the left ventricular apex and the direction of the ultrasonic beam was positioned to be parallel with mitral flow using the Doppler audio signals. A pressure gradient was calculated from continuous wave Doppler flow velocity with a simplified Bernoulli's equation proposed by Hatle et al. The peak and mean maximum flow velocity, mean pressure gradient across the valve and the pressure half time were measured to evaluate the opening function of the prosthetic valve. The results were as follows: All four measurements were significantly larger in patients with valve replacements than in normal subjects, and were significantly increased in patients with porcine xenograft valves compared to those with St. Jude Medical valves. The opening function was well maintained in patients having larger valves than in those having smaller ones in the group of St. Jude Medical valve replacement. In patients who had porcine xenograft valve for four years or more, the opening function was decreased the more years they had been implanted. We conclude that continuous wave Doppler echocardiography is a useful noninvasive method for the quantitative assessment of the diastolic opening function of the prosthetic mitral valve.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

[Systolic honk in mitral stenosis: a case report].

This case report describes a mitral systolic honk originating from the mitral valve and adjacent structures in a 52 year-old woman with mitral stenosis. The patient was hospitalized because of dyspnea. Auscultation of the heart revealed a grade 3/6 apical early systolic honk accompanied by an increased first heart sound, an opening snap and a diastolic rumble. The phonocardiogram demonstrated an early systolic honk at a frequency of 115 Hz. Intensity of the honk varied on beat to beat basis, increasing in the short preceding R-R interval compared to that in the long one. The M-mode echocardiogram showed early systolic fluttering of the mitral valve and chordae tendineae at the same frequency as the honk. The two-dimensional echocardiogram showed bulging of the anterior mitral leaflet toward the left atrium in early systole. After treatment with digitalis and diuretics, the early systolic honk disappeared in beats with preceding long R-R intervals (greater than 1100 msec). In beats without the honk, systolic fluttering of the mitral valve was not observed. The genesis of the early systolic honk is analogous to that of the honk audible in mitral or tricuspid valve prolapse. The bulging of the anterior mitral leaflet into the left atrium may produce vibrations of the mitral valve leaflets and adjacent structures.

Chordae Tendineae↗
PubMed1985

[Continuous wave Doppler echocardiographic assessment of aortic stenosis and aortic regurgitation].

Twenty-four patients with aortic stenosis and 22 with aortic insufficiency were evaluated using continuous wave Doppler echocardiography (echo). Doppler echo studies were performed 48 hours before cardiac catheterization. Fifteen normal subjects served as controls. Peak velocity in the ascending aorta in aortic stenosis ranged from 2.0 to 6.0 m/sec with a mean of 3.7 m/sec, and this was significantly increased over the normal controls (mean 1.1 m/sec: 0.7-1.4 m/sec). Using the simplified Bernoulli equation (P = 4 V2, P: peak pressure gradient, V: peak flow velocity), the peak pressure gradient across the aortic valve was measured from the peak velocity in patients with aortic stenosis. The results (Y) correlated well with the peak-to-peak pressure gradient (X) between the left ventricular pressure and aortic pressure as obtained by cardiac catheterization (Y = 1.1 X +2.5, r = 0.83). Aortic regurgitation was detected by continuous wave Doppler echo in all patients with aortic insufficiency, but in only half of the patients the peak velocity could be measured (3.8 +/- 0.3 m/sec, mean +/- SD). In the remaining patients, it was difficult to measure the peak velocity, but it seemed to be greater than 3.0 m/sec. On the simultaneous recordings of the gradient between aortic and left ventricular pressures and continuous wave Doppler echo in patients with aortic regurgitation, the shape and pattern of the pressure gradient during diastole were similar to those of continuous wave Doppler echo. We conclude that continuous wave Doppler echo is a very sensitive method for diagnosing aortic stenosis and regurgitation, and it provides a quantitative assessment of the severity of aortic stenosis.

Adult↗
PubMed1985

[Noninvasive estimation of pressure gradient in the left ventricular outflow tract: an experimental study].

The relationship between systolic anterior motion of the mitral valve (SAM) and left ventricular outflow pressure gradient (PG) was examined in five dogs with experimentally-produced SAM. A total of 155 heart beats including 29 post-extrasystolic beats with various PG were analyzed. Correlations of PG with the time from the onset of left ventricular ejection to the onset of SAM-septal contact (SSC), SSC divided by ejection time (ET) (SSC/ET), and SSC/ET multiplied by the pre-ejection period (PEP) (PEP X SSC/ET) were obtained. The relation between the natural logarithm of PG (InPG) and SSC/ET was expressed by the linear regression equation: InPG = -5.16X + 5.19, with the correlation coefficient (r) of -0.88 for total 155 beats (r ranged from -0.75 to -0.96 for each dog), and the relation between InPG and PEP X SSC/ET by the formula of InPG = -0.075X + 5.35, with the r of -0.91 for total 155 beats (r ranged from -0.84 to -0.95 for each dog). These results indicated that the time from the onset of aortic ejection to the onset of SAM-septal contact is strongly dependent on the degree of PG.

Animals↗