ISSN:0009-7322    

出版商:OVID    

年代:1987

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

A cohort of 2270 white women, aged 40-69 years at baseline, were followed for an average of 8.5 years in the Lipid Research Clinics Program Follow-up Study. There were 44 deaths due to cardiovascular disease among the 1677 nonusers of estrogens and six cardiovascular disease deaths among the 593 estrogen users. The age-adjusted relative risk (RR) of cardiovascular disease deaths in users compared with nonusers was 0.34 (95% confidence limits 0.12 to 0.81). After multivariable adjustment for potential confounding factors (age, blood pressure, and smoking), the estimated RR for estrogen use was 0.37 (95% confidence limits 0.16 to 0.88). Analyses were done to explore whether these results could be due to selection bias for estrogen use. However, the prevalence of cardiovascular disease at baseline was slightly higher in estrogen users (12%) than in nonusers (10%); furthermore, the exclusion of all women with prevalent cardiovascular disease at baseline did not alter the apparent protective effect of estrogen use on cardiovascular disease mortality (RR = 0.42, 95% confidence limits 0.13 to 1.10). Additional analyses examining the complex association between estrogen use, lipoprotein levels, and cardiovascular disease mortality suggest that the protective effect of estrogen is substantially mediated through increased high-density lipoprotein levels.

ISSN:0009-7322    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

A total of 349 patients with vasospastic angina were followed in eight centers in Japan for a period of 3.4 ± 0.1 years (mean ± SE). Ninety-eight percent of patients were treated with calcium blockers. Twenty-one episodes of myocardial infarction occurred in 18 patients (5%), including two fatal myocardial infarctions. The rate of myocardial infarction was higher (p < .01) in patients with a fixed stenosis of 90% or greater than in patients with a fixed stenosis of less than 90% or normal coronary arteries. Myocardial infarctions occurred predominantly during hospital stays or at a time when the frequency of vasospastic angina increased. There were five sudden deaths (2%). Only one patient suffering sudden death had a fixed stenosis of 75% or greater. Serious arrhythmias were noted in 49 patients (14%). The risk of arrhythmias did not depend on the presence of a fixed stenosis of 75% or greater. These results suggest that cardiac events are rather infrequent in Japanese patients with vasospastic angina who are receiving treatment with calcium blockers and that the presence of a severe fixed stenosis markedly increases the risk of myocardial infarction but not the risk of arrhythmias.

ISSN:0009-7322    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

We analyzed the flow velocity pattern in the main pulmonary artery after Fontan operation in patients with tricuspid atresia (n = 10) or with single ventricle (n = 10) by means of a catheter-mounted velocity probe. The area underneath the velocity signal of the forward flow was integrated, and ratios of the portions during atrial systole and during the diastolic phase to the total area (Fa and Fd) were calculated. The Fa was 0.54 ± 0.09 in patients with tricuspid atresia and 0.45 ± 0.05 in those with single ventricle (p < .01). Cardiac output, obtained by the thermodilution method, was 2.45 ± 0.48 liters/min/m2 in patients with tricuspid atresia and 2.75 ± 0.72 liters/min/m2 in those with single ventricle. The forward flow during atrial contraction, calculated by multiplying Fa by cardiac output, was 1.32 ± 0.35 liters/min/m2 in patients with tricuspid atresia and 1.23 ± 0.33 liters/min/m2 in those with single ventricle. The diastolic forward flow, calculated from Fd and cardiac output, was 0.99 ± 0.25 liter/min/m2 in patients with tricuspid atresia and 1.52 ± 0.45 liters/min/m2 in those with single ventricle (p < 0.005). The sum of cross-sectional areas of the right and left pulmonary arteries normalized by body surface area (PA index) was 282 ± 85 cm2/m2 in patients with tricuspid atresia and 462 ± 65 cm2/m2 in those with single ventricle (p < .005). The Fa was inversely correlated with the PA index in the whole group (r = − .69) and also in the tricuspid atresia group alone (r = − .87). Postoperative right atrial and pulmonary arterial pressures were 16 ± 3 and 16 ± 4 mm Hg in patients with tricuspid atresia and 15 ± 3 and 13 ± 3 mm Hg in those with single ventricle. Right atrial maximum volume, determined angiographically, was 169 ± 87% of normal in patients with tricuspid atresia and 105 ± 32% of normal in those with single ventricle (p < .01), but the ejection fraction was similar in the two groups (0. 30 ± 0.08 vs 0.29 ± 0.06). The data indicate that the relative role of right atrial contraction may become more important in patients with a smaller PA index, right atrial output is constant regardless of the PA index or the type of anomalies, and the amount of diastolic forward flow is influenced by the PA index. Thus the preoperative PA index is an important determinant of postoperative hemodynamics.

ISSN:0009-7322    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

The purpose of this study was to test the hypothesis that the presence of a subaortic ridge associated with a ventricular septal defect (VSD) is related to a malaligned ventricular septum caused by anterior or posterior deviation of the infundibular septum with or without obstructive lesions of the aortic arch. Thirty-two of 295 patients in whom a diagnosis of VSD was made by two-dimensional echocardiography and who were studied from June 1983 to Apnrl 1985 presented with a subaortic shelf. Every patient (p < .00001) had a malalignment type of defect; the defect was produced by anterior deviation of the outlet septumn (without compromise of the right ventricular outflow tract) in 28 and by posterior deviation of the infundibular septum in four. The prevalence of a subaortic shelf in the malalignment VSD group was 82% (32/39). Among the 28 patients with a subaortic ridge and anterior deviation of the outlet septum only three had aortic coarctation, but all four patients with subaortic stenosis and posterior infundibular malalignment had obstructive lesions of the aortic arch coarctation in three and interruption of the aortic arch in one (p < .00 1). We conclude that a malalignment type of VSD may be a consistent feature in patients with VSD and associated discrete subaortic stenosis. We also noted a high prevalence of subaortic ridge in the presence of a malalignment VSD and therefore speculate that there may be a common morphogenesis for malalignment VSD, subaortic shelf, and obstructive lesions of the aortic arch.

ISSN:0009-7322    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

To clarify the pathophysiologic role of intramyocardial small artery (IMSA) diseases in hypertrophied hearts, narrowings of the IMSA were quantitatively evaluated in 39 autopsied hearts, 10 from patients with typical hypertrophic cardiomyopathy (HCM), four from patients with HCM showing features mimicking dilated cardiomyopathy (DCM-like HCM), 10 from patients with hypertension, and 15 from normal adults. The relations of narrowings of the IMSA to myocytic hypertrophy, myocardial fiber disarray, and fibrosis were also examined. The external caliber and the ratio of the luminal area to the total vascular area (percent luminal area, %lumen) were calculated by an image analyzer in 85 to 203 IMSAs from each patient. The external calibers of the IMSAs were similar among groups of hearts with HCM, hypertensive hearts, and normal hearts but were greater in those with DCM-like HCM. The mean %lumen of the IMSAs was similarly reduced in the hearts with HCM (29 ± 5% in the ventricular septum and 31 5% in the left ventricular free wall) and in hypertensive hearts (30 ± 8% and 31 ± 7%) compared with that in normal hearts (40 5% and 38 ± 5%) and was the lowest in the ventricular septum of hearts with DCM-like HCM (17 3%). The mean %lumen of the IMSA was inversely cortelated with heart weight (r = −.59), the mean size of myocytes (r = − .66 in the ventricular septum, r = − .63 in the free wall), and percent fibrotic area in the septum (r = −.68). The mean %lumen values of the IMSAs in the tissues with and without disarray in the hearts with HCM were similar. Thus IMSA disease is of pathophysiologic importance in patients with HCM, DCM-like HCM in particular, or with hypertension.

ISSN:0009-7322    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

The evolution of Chagas' cardiomyopathy is poorly understood. We therefore examined the development of cardiac lesions in a rural Brazilian community for a period of 7 years. Initially, 42% of 1017 residents were seropositive for infection with Trypanosoma cruzi. Age-specific infection rates indicated that most had become infected before the age of 20 years. On follow-up, it appeared that those persons who developed cardiac lesions did so soon after infection, since the incidence of right bundle branch block and other ventricular conduction defects (VCDs) was also highest before age 20 years. The progressive nature of these lesions was demonstrated by frequent development of additional electrocardiographic abnormalities and high mortality among infected adults with VCDs. In contrast, mortality was low and approximately the same for seropositive and seronegative adults under 60 years who had normal electrocardiograms. Electrocardiography during the early asymptomatic stage of infection was able to distinguish persons with potentially lethal cardiac lesions from those with a benign prognosis.

ISSN:0009-7322    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

The pulsed Doppler technique was used to record the flow velocity patterns in the ductus arteriosus and the pulmonary artery in 26 patients with either isolated or complicated patent ductus arteriosus (PDA). In all patients, abnormal Doppler signals indicating left-to-right (L-R) or right-to-left shunt flow or both could be obtained at the site of the ductus arteriosus. These Doppler flow patterns determined within the ductus coincided with the direction of ductal flow seen on the contrast two-dimensional echocardiogram. No Doppler signals of shunt flow were demonstrated in any of 42 control subjects. The peak, mean, and diastolic velocities of the L-R shunt flow within the ductus were measured from the ductal flow velocity profiles. With the Doppler-derived measurements of the mean and diastolic velocities, patients with normal pulmonary arterial pressure and those with evidence of pulmonary hypertension could be correctly identified. In addition, the mean velocity of the diastolic antegrade flow portion obtained from the proximal left pulmonary artery, which was related to ductal L-R shunting, was measured in 16 patients with isolated PDA. This Doppler flow determinant showed a good linear correlation with the L-R shunt ratio determined by Fick's method (r = .88, p < .01). Our technique permits the noninvasive evaluation of shunt flow dynamics in patients with PDA.

ISSN:0009-7322    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

To study the relationship between the quantitatively assessed coronary artery dimensions and the regional coronary flow reserve as measured by digital subtraction cineangiography, we investigated 17 coronary arteries with a single discrete proximal stenosis and 12 normal coronary arteries before and after intracoronary administration of papaverine. Coronary flow reserve was found to be curvilinearly related to minimal luminal cross-sectional area (r = .92, SEE = 0.73) and to percentage area stenosis (r = .92, SEE = 0.74). Normal coronary arteries had a coronary flow reserve of 5.0 (±±0.8 [SD]), which differed significantly from the coronary flow reserve of the coronary arteries with obstructive disease, In which values ranging from 0.5 to 3.9 were found. Coronary arteries with a percentage area stenosis between 50% and 70% and a minimal luminal cross-sectional area between 2 and 4.5 mm2 differed significantly (p = .001), with respect to the coronary flow reserve, from coronary arteries with a percentage area stenosis in excess of 70% and a minimal luminal crosssectional area less than 2 mm2. With the use of hemodynamic equations that describe the pressure loss over a stenosis, a theoretical pressure-flow relationship can be inferred that characterizes the severity of the stenosis. Based on this theoretical pressure-flow relationship, coronary arteries that have a limited coronary flow reserve and critical stenosis (distal coronary perfusion pressure below 40 mm Hg at coronary flow of 3 ml/sec) can be identified with high sensitivity (83%) and specificity (82%). Thus, in coronary artery disease the consequent reduction in coronary flow reserve can be predicted withreasonable accuracy by quantitative assessment of coronary artery dimensions.

ISSN:0009-7322    

出版商:OVID    

年代:1987

数据来源: OVID