PubMed Health⌕ Search

Biomedical subjects

C Tei

Publications and source records attributed to C Tei.

At least 73 records · Page 4Linked to original sources
PubMed1998

Value of a Doppler-derived index combining systolic and diastolic time intervals in predicting outcome in primary pulmonary hypertension.

Primary pulmonary hypertension is characterized by elevated pulmonary arterial pressure and vascular resistance, frequently producing right heart failure and death. Therefore, the Doppler right ventricular (RV) index, which is a measure of global RV function, could be a useful predictor of outcome in primary pulmonary hypertension. The Doppler RV index, defined as the sum of isovolumic contraction time and isovolumic relaxation time divided by ejection time, was retrospectively measured in 53 patients (38 women, aged 45 +/- 14 years) with primary pulmonary hypertension. Ejection time was measured from the pulmonary outflow velocity signal. The sum of isovolumic contraction time and isovolumic relaxation time was obtained by subtracting ejection time from the duration of tricuspid regurgitation. The Doppler RV index tended to be elevated (median 0.83) compared with normal ranges. Normal Doppler RV index was 0.28 +/- 0.04. After a mean follow-up duration of 2.9 years, 4 patients underwent lung transplantation and 30 patients died; the cause was cardiac in 28, noncardiac in 1, and uncertain in 1. Univariately, the Doppler RV index (chi-square 20.7, p <0.0001), severity of tricuspid regurgitation (chi-square 8.2, p = 0.004), treatment with calcium blockers (chi-square 6.6, p = 0.01), heart rate (chi-square 5.1, p = 0.02), and symptom status (chi-square 4.9, p = 0.03) were associated with adverse outcome (cardiac deaths and lung transplantation). However, only the Doppler RV index and treatment with calcium blockers were independent predictors within the multivariate model. Our results indicate that the Doppler RV index is a useful predictor of adverse outcome in patients with primary pulmonary hypertension.

Adult↗
PubMed1998

Nongeometric quantitative assessment of right and left ventricular function: myocardial performance index in normal children and patients with Ebstein anomaly.

Assessment of ventricular systolic function has been based on the geometric models of ventricular shape. This study was designed to define normal values for a nongeometric myocardial performance index (MPI) in children and to evaluate the utility of MPI in congenital heart disease. The MPI measures the ratio of total time spent in isovolumic activity (isovolumic contraction time and isovolumic relaxation time) to the ejection time. The right ventricular (RV) and left ventricular (LV) MPI were measured in 152 normal children (ages 3 to 18 years) and 45 preoperative patients with Ebstein anomaly (age 1 week to 52 years). In normal children, the RV MPI was 0.32+/-0.03 and the LV MPI was 0.35+/-0.03. In the Ebstein group, both RV and LV MPI were abnormally increased compared with age-matched normal subjects (Ebstein group: RV MPI=0.49+/-0.12, LV MPI=0.42+/-0.09, P < .001). Increasing RV dysfunction was associated with progressively increasing (abnormal) values of RV MPI (P < .001). The myocardial performance index quantitatively reflects ventricular performance in patients with complex ventricular geometry (ie, Ebstein anomaly). In the absence of a geometric solution, this nongeometric index is particularly appealing for the assessment of RV or LV performance.

Adolescent↗
PubMed1998

Changes of the carotid artery Doppler flow velocity pattern after sublingual nitroglycerin in patients with hypertension.

OBJECTIVE: To evaluate the applicability of carotid Doppler echography for the assessment of changes of peripheral hemodynamics in the hypertensives. SUBJECTS: 28 hypertensives (17 males, 11 females), mean age of 64 yrs and 40 normal controls (24 males, 16 females) mean age of 49 yrs. METHODS: We recorded the right common carotid arterial Doppler flow velocity (BFV) pattern and measured the peak velocities of the percussion wave (P) and late rising tidal wave (T), the ratio of the two (P/T), the time interval between the two peaks corrected by heart rate (P-Tc), systolic flow velocity integral (FVI) and carotid artery diameter (CAD) before and after 0.4 mg dose of subligual nitroglycerin (NTG). RESULTS: 1) In hypertensives, the P wave velocity showed lower and P-Tc interval shorter than those of the normal controls at baseline. 2) After NTG, the P-Tc and P/T increased, but the T and FVI decreased significantly in both groups of subjects. 3) The P/T ratio was less significantly increased after NTG in the hypertensives than in the controls. These results suggest that NTG might have been involved in concomitant reduction and delay of the wave reflection from the peripheral vessels, preferentially in the normal subjects than in hypertensives. CONCLUSIONS: The carotid Doppler echography can be useful for the evaluation of the changes of hemodynamics in the peripheral vessel such as carotid artery in hypertensive subjects.

Administration, Sublingual↗
PubMed1998

Effect of danazol on the pregnancy rate in patients with unsuccessful in vitro fertilization-embryo transfer.

OBJECTIVE: To determine the effect of danazol on in vitro fertilization-embryo transfer (IVF-ET) patients who failed to conceive in previous attempts despite having embryos with optimal morphology, whether endometriosis is present or not. STUDY DESIGN: In this prospective, randomized, controlled study, of 81 patients who experienced unexplained failures of IVF-ET despite having good-morphology embryos, 40 received danazol (400 mg/d orally for 12 weeks) following the unsuccessful IVF-ET cycle. The next IVF-ET was performed within three months of the first spontaneous ovulation after danazol administration. The remaining 41 patients constituted the control group, and in them the next IVF-ET was performed within six months after the previous failed cycle. RESULTS: Conception occurred in 16 of 40 (40%) danazol-treated patients at the subsequent cycle and showed a significant increase when compared with 8 of 41 (19.5%) control subjects (P < .05), though the number of embryos with optimal morphology decreased after danazol treatment. CONCLUSION: Danazol may be used for patients who have had repeated failures of IVF-ET despite having morphologically optimal embryos and may be useful for increasing receptivity of the endometrium in these patients.

Autoantibodies↗
PubMed1998

Functional mitral regurgitation.

Functional MR is an important complication, which adversely affects the prognosis of patients with ischemic heart disease or global LV dysfunction. Two-dimensional Doppler echocardiography is a noninvasive and useful method for the diagnosis of functional MR. However, the pathophysiology of functional MR is not yet established, therefore, extensive investigations are necessary to understand its basic mechanism and establish effective and practical method for the prevention and treatment of functional MR.

Animals↗
PubMed1997

Pericardial thickness measured with transesophageal echocardiography: feasibility and potential clinical usefulness.

OBJECTIVES: This study assessed the reliability of transesophageal echocardiographic measurements of pericardial thickness and the potential diagnostic usefulness of this technique. BACKGROUND: Transthoracic echocardiography cannot reliably detect thickened pericardium. The superior resolution achieved with transesophageal echocardiography should allow better pericardial definition. METHODS: Pericardial thickness measured at 26 locations in 11 patients with constrictive pericarditis who underwent intraoperative transesophageal echocardiography was compared with pericardial thickness measured with electron beam computed tomography. Intraobserver and interobserver variabilities were determined. Pericardial thickness was then measured in 21 normal subjects. With these values as a guide, two observers reviewed 37 transesophageal echocardiographic studies to determine whether echocardiographic measurement of pericardial thickness could be used to distinguish diseased from normal pericardium. RESULTS: The correlation between echocardiographic and computed tomographic measurements (r > or = 0.95, SE < or = 0.06 mm, p < 0.0001) was excellent. The +/-2 SD limits of agreement were +/-1.0 mm or less for pericardial thickness < 5.5 mm and +/-2.0 mm or less for the entire range of thicknesses. Intraobserver and interobserver agreements were good. Mean normal pericardial thickness was 1.2 +/- 0.8 mm (+/-2 SD) and did not exceed 2.5 mm. Pericardial thickness > or = 3 mm on transesophageal echocardiography was 95% sensitive and 86% specific for the detection of thickened pericardium. CONCLUSIONS: Measurement of pericardial thickness with transesophageal echocardiography is reproducible and should be a valuable adjunct in assessing constrictive pericarditis.

Case-Control Studies↗
PubMed1997

Noninvasive Doppler-derived myocardial performance index: correlation with simultaneous measurements of cardiac catheterization measurements.

A simple, reproducible, noninvasive Doppler index for the assessment of overall cardiac function has been described previously. The purpose of this study was to correlate the Doppler index with accepted indexes of cardiac catheterization of left ventricular performance. Thirty-four patients with ischemic heart disease or idiopathic dilated cardiomyopathy prospectively underwent a simultaneous cardiac catheterization and Doppler echocardiographic study. Invasive measurements of peak +dP/dt, peak -dP/dt, and tau were obtained from the high-fidelity left ventricular pressures. A Doppler index of myocardial performance was defined as the summation of isovolumetric contraction and relaxation time divided by ejection time. There was a correlation between Doppler measurement of isovolumetric contraction time and peak +dP/dt (r = 0.842; p < 0.0001) and Doppler measurement of isovolumetric relaxation time and peak -dP/dt (r = 0.638; p < 0.001). Left ventricular ejection time correlated with both peak +dP/dt (r = 0.539; p < 0.001) and peak -dP/dt (r = 0.582; p < 0.001). The Doppler index correlated with simultaneously recorded systolic peak +dP/dt (r = 0.821; p < 0.0001) and diastolic peak -dP/dt (r = 0.833; p < 0.001) and tau (r = 0.680; p < 0.0001). This study documents that a simple, easily recordable, noninvasive Doppler index of myocardial performance correlates with invasive measurement of left ventricular systolic and diastolic function and appears to be a promising noninvasive measurement of overall cardiac function.

Aged↗
PubMed1997

A case of cor triatriatum in an eighty-year-old man: transesophageal echocardiographic observation of multiple defects.

An 80-year-old man was admitted to the hospital because of recurrent syncope caused by sick sinus syndrome. Conventional transthoracic echocardiography showed a membranelike echo-dense structure across the left atrium. Subsequently we confirmed the diagnosis of cor triatriatum with multiple defects and shunt flows across the membrane by transesophageal color flow Doppler echocardiography. There were no other associated congenital anomalies. The patient recovered well and was discharged from the hospital after implantation of a permanent VVI pacemaker for sinus node dysfunction. No other cardiac intervention for the cor triatriatum was done except follow-up with echocardiography. About 1 year after discharge, he died of massive cerebral infarction. The cardiac autopsy findings were compatible with the transesophageal echocardiogram. This is a rare case of uncorrected cor triatriatum in an elderly patient.

Aged↗
PubMed1997

Effects of nitric oxide on ovulation and ovarian steroidogenesis and prostaglandin production in the rabbit.

Evidence supports the involvement of nitric oxide (NO) in ovarian physiology. The present study was undertaken to investigate the role of the NO/NO synthase (NOS) systems in ovulation, oocyte maturation, ovarian steroidogenesis, and PG production using in vitro perfused rabbit ovaries. The addition of the NOS inhibitors, aminoguanidine hemisulfate salt (AG) and N-omega-nitro-L-arginine methyl ester (L-NAME), to the perfusate inhibited the ovulation induced by hCG in a dose-dependent manner, whereas D-NAME had no significant effect. Neither AG nor L-NAME affected the hCG-induced meiotic maturation of the ovulated ova. The exogenous administration of the NO generator, sodium nitroprusside (NP), induced follicle rupture in the absence of gonadotropin, but did not induce oocyte maturation. Inhibition of endogenous NOS by AG and L-NAME resulted in a significant elevation in the production of estradiol (E2), but not of progesterone, stimulated by hCG. The concomitant administration of NP significantly reduced the AG-stimulated production of E2 by ovaries perfused in the presence of hCG, which suggests that NO down-regulates ovarian E2 synthesis. Ovarian production of PGE2 and PGF2alpha in response to hCG was significantly blocked by L-NAME, and exogenous administration of NP stimulated the production of PGs in the absence of gonadotropin. Significant correlations were observed between the ovulatory efficiencies and the production of PGs by rabbit ovaries perfused with or without L-NAME. In conclusion, the ovarian NO/NOS system is involved in follicle rupture during the ovulatory process. NO may induce follicle rupture in rabbit ovaries at least in part by the stimulation of PG production.

Animals↗
PubMed1997

[Transthoracic Doppler echocardiographic detection of intramyocardial coronary artery flow in humans using high frequency transducer].

The use of transthoracic color and pulsed Doppler echocardiography to detect intramyocardial coronary artery flow in humans was evaluated in 18 normal healthy subjects (mean age 54 years) and in 16 patients with hypertrophic cardiomyopathy (HCM; mean age 59 years) to measure the intramyocardial coronary artery flow velocity at the ventricular septum and the apex using a 10-5 or 7-4 MHz transducer. Linear inflow color Doppler signals which passed the interventricular septum were demonstrated in 15 of 18 normal subjects (83%) and 15 of 16 patients with HCM (94%). The phasic flow velocities measured by pulsed Doppler echocardiography consisted of two forward flow signals in mid-systole (S-wave) and holodiastole (D-wave), and were obtained in 11 of 18 in normal subjects (61%) and 14 of 16 patients with HCM (88%). The mean peak velocities of the S- and D-waves in patients with HCM (mean [+/-SD] 27 +/- 9 and 86 +/- 23 cm/sec, respectively) were significantly (p < 0.05) higher than those in normal subjects (18 +/- 4 and 54 +/- 11 cm/sec, respectively). At the apex, linear inflow color Doppler signals which passed the myocardium perpendicularly during the whole diastole were demonstrated in 14 of 18 normal subjects (78%) and all 16 patients with HCM (100%). The phasic flow velocities were measured by pulsed Doppler echocardiography in 10 of 18 normal subjects (56%) and 15 of 16 patients with HCM (94%). The mean peak velocities in patients with HCM (74 +/- 27 cm/sec) were significantly (p < 0.05) higher than those in normal subjects (33 +/- 13 cm/sec). Transthoracic color and pulsed Doppler echocardiography can detect intramyocardial coronary artery flow in humans at the interventricular septum and the apex noninvasively.

Blood Flow Velocity↗
PubMed1996

Doppler index combining systolic and diastolic myocardial performance: clinical value in cardiac amyloidosis.

OBJECTIVES: This study was designed to determine the clinical value of a Doppler-derived index of combined systolic and diastolic myocardial performance in the assessment of cardiac amyloidosis. BACKGROUND: Cardiac amyloidosis is an infiltrative disease with diastolic and systolic dysfunction. Therefore, the index of myocardial performance combining systolic and diastolic time intervals could be a useful predictor of clinical outcome in cardiac amyloidosis. METHODS: The study included 45 patients with biopsy-proved amyloidosis and 45 age-matched normal subjects. All patients had typical echocardiographic features of amyloid cardiac involvement. A Doppler-derived index, defined as the sum of isovolumetric contraction time and isovolumetric relaxation time divided by ejection time, was measured from left ventricular outflow and mitral inflow Doppler velocity profiles recorded during routine echocardiography. The index as well as conventional systolic or diastolic echocardiographic/Doppler variables were related to subsequent outcome. RESULTS: The isovolumetric contraction and relaxation times were prolonged and ejection time was shortened (p < 0.001) in patients with amyloidosis compared with that in normal subjects, resulting in a marked increase of the index from normal values (p < 0.001). In the amyloid group the index was highest in patients with a low stroke index or with both shortened mitral deceleration time and lower ejection fraction. By univariate analysis, New York Heart Association functional class, the index, ejection fraction and mitral deceleration time were significant predictors of outcome. However, by multivariate stepwise regression analysis, functional class and the index were the only independent predictors of survival. CONCLUSIONS: The Doppler-derived index of combined systolic and diastolic myocardial performance correlates with global cardiac dysfunction and is a useful predictor of clinical outcome in patients with cardiac amyloidosis.

Adult↗
PubMed1995

Acute hemodynamic improvement by thermal vasodilation in congestive heart failure.

BACKGROUND: A warm-water bath (WWB) or sauna bath (SB) has generally been considered inappropriate for patients with severe congestive heart failure (CHF). However, a comprehensive investigation of the hemodynamic effects of thermal vasodilation in CHF has not been previously undertaken. METHODS AND RESULTS: To investigate the acute hemodynamic effects of thermal vasodilation in CHF, we studied 34 patients with chronic CHF (mean age, 58 +/- 14 years). Clinical stages were New York Heart Association functional class II in 2, III in 19, and IV in 13 patients. Mean ejection fraction was 25 +/- 9%. After a Swan-Ganz catheter was inserted via the right jugular vein, the patient had a WWB for 10 minutes at 41 degrees C or an SB for 15 minutes at 60 degrees C. Blood pressure, ECG, echo-Doppler, expiration gas, and intracardiac pressures were recorded before, during, and 30 minutes after each bath. Oxygen consumption increased mildly, pulmonary arterial blood temperature increased by 1.2 degrees C, and heart rate increased by 20 to 25 beats per minute on average at the end of WWB or SB. Systolic blood pressure showed no significant change. Diastolic blood pressure decreased significantly during SB (P < .01). Cardiac and stroke indexes increased and systemic vascular resistances decreased significantly during and after WWB and SB (P < .01). Mean pulmonary artery, mean pulmonary capillary wedge, and mean right atrial pressures increased significantly during WWB (P < .05) but decreased significantly during SB (P < .05). These pressures decreased significantly from the control level after each bath (P < .01). Mitral regurgitation associated with CHF decreased during and 30 minutes after each bath. Cardiac dimensions decreased and left ventricular ejection fraction increased significantly after WWB and SB. In an additional study, plasma norepinephrine increased significantly during SB in healthy control subjects and in patients with CHF and returned to control levels by 30 minutes after SB. CONCLUSIONS: Hemodynamics improve after WWB or SB in patients with chronic CHF. This is attributable to the reduction in cardiac preload and afterload. Thus, thermal vasodilation can be applied with little risk if appropriately performed and may provide a new nonpharmacological therapy for CHF.

Adolescent↗