Dilatation In Women Research Articles

Impaired vascular dilatation in women with a history of pre-eclampsia

The mechanisms underlying increased cardiovascular risk among women with a history of pre-eclampsia remain unclear. Impaired endothelial function has been observed in both pre-eclampsia and atherosclerosis, and provides a plausible link between the two conditions. We studied endothelial function and arterial compliance in non-pregnant, previously pre-eclamptic women. A study of 30 women with a history of pre-eclampsia and 21 women with a previous normotensive, uncomplicated pregnancy was carried out. Changes in brachial artery blood flow, induced by intra-arterial infusions of an endothelium-independent (sodium nitroprusside) and an endothelium-dependent (acetylcholine) vasodilator, were measured by venous occlusion plethysmography. Arterial stiffness was assessed by pulse-wave analysis. Vasodilatation was impaired in women with previous pre-eclampsia; at low and high concentrations of endothelium-independent (P = 0.004 and P = 0.057, respectively) and endothelium-dependent (P = 0.045 and P = 0.02) vasodilators, respectively. There was no difference in arterial stiffness between the groups (P = 0.45). In multiple regression analyses both endothelium-independent and endothelium-dependent vasodilatations were independently associated with a history of pre-eclampsia and parity. There was no correlation with blood pressure, body mass index (BMI), smoking or age. The finding of impaired vascular dilatation several years after a pre-eclamptic pregnancy could contribute to the higher risk of cardiovascular disease in these women.

Apo e4 allele is associated with endothelium-dependent arterial dilation in women with type 2 diabetes

Objective Previous studies have suggested that the e4 allele of apolipoprotein E (apo E) relates to the endothelium-dependent arterial dilation in men with type 2 diabetes. This study attempted to assess whether apo e4 allele is associated with endothelial dysfunction in women with type 2 diabetes. Research design and methods We selected 144 Chinese Han female type 2 diabetic patients without clinically detectable angiopathy. Polymerase chain reaction/ASO probes were used to determine their mouthwash DNA apo E genotypes, and high-resolution ultrasound was used to measure brachial artery diameter at rest, after reactive hyperemia (with increased flow causing endothelium-dependent dilation) and after sublingual glyceryltrinitrate (GTN, an endothelium-independent dilator). Results The flow-mediated arterial dilation among the subjects with e4/3 or e4/4 was 3.56 ± 0.23%, which was significantly lower than that in subjects with e2/2 or e3/2 (3.97 ± 0.36%) ( p = 0.000). The baseline vessel size, GTN-induced dilation and baseline blood flows were not significantly different among different apo E genotypes. On univariate analysis, reduced flow-mediated arterial dilation was significantly related to total cholesterol, LDL, Lp(a), high blood pressure, older age, family history of premature vascular disease, larger vessel size, duration of diabetes and e4 allele ( p < 0.05). By multiple stepwise regression analysis, reduced flow-mediated arterial dilation was associated with older age, large vessel size, duration of diabetes, positive family history, LDL, Lp(a) and e4 allele ( p < 0.01). Conclusion The apo e4 allele is associated with impairment of endothelium-dependent arterial dilation in the relatively early stage of female type 2 diabetes.

Characteristics And Determinants Of Age-related Changes In Brachial And Popliteal Artery Flow-mediated Dilation In Women

Flow-mediated dilation (FMD) declines in the brachial artery (BA) with healthy aging in women. However, the physiological determinants of this decline are not welled fined, particularly after the BA FMD response has been normalized to the shear stress stimulus. Furthermore, it is not known whether this diminished FMD is seen in the leg vasculature (popliteal artery, PA), a more hemodynamically significant vascular bed utilized during ambulatory activities. PURPOSE To determine the characteristics and determinants of age-related changes in BA and PA FMD in healthy women. METHODS 41 normally active, healthy women (ages 20–79) were measured for variables including cycle VO2peak, body mass index (BMI) and regional muscle mass (forearm and calf). Resting PA and BA diameters and BA shear rate (SR= blood velocity/diameter, an estimate of shear stress) were measured prior to infiation of an upper arm or leg cuff to suprasystolic pressure for 10 min; post-occlusion diameter measurements and peak BA shear rate were used to calculate BA and PA dilation (% D = % change from baseline to peak diameter) and BA % D normalized to shear stimulus (% D/% change in SR from resting to peak). Simple linear regression was used to determine the age-associated changes in BA and PA FMD; forward/reverse stepwise linear regression was then used to determine the predictors of these age-related changes. RESULTS Resting BA and PA diameters did not differ with age (p>0.05). BA FMD normalized to shear stimulus declined 11.6% /decade with age (p <0.01); the strongest predictors of this decline were age, VO2peak, and forearm muscle mass (cumulative r2=.41; p=0.01). PA % D was not related to age (p>0.05). The only significant predictors of PA FMD were calf muscle mass (p=0.03, r2=.112) and BMI (p=0.03; r2=.121). CONCLUSION These results suggest that agerelated changes in the intrinsic dilator capacity of a conduit artery are limb-specific; additionally, the strong predictive ability of forearm flow-mediated dilation does not exist in the calf with predictors such as regional muscle mass and VO2peak. Supported by College of Health and Human Development Seed Grant #423-22

Characteristics And Determinants Of Age-related Changes In Brachial And Popliteal Artery Flow-mediated Dilation In Women

Characteristics And Determinants Of Age-related Changes In Brachial And Popliteal Artery Flow-mediated Dilation In Women

Hypertension is a major risk factor for aortic root dilatation in women with Turner's syndrome.

Women with Turner's syndrome (TS) have a threefold increase in mortality, primarily as a result of their cardiovascular complications. Recently, the risk of fatal aortic dissection has come to light as a major cause of mortality in women with TS. The aim of this study was to assess the prevalence of aortic root dilatation in a group of women with TS and to investigate the factors contributing to its development. Thirty-eight women with TS attending a dedicated adult Turner clinic were examined clinically and by M-mode and two-dimensional echocardiography on at least one occasion. Aortic root dilatation was defined as an aortic root diameter greater than the 95th centile for body surface area. Fasting serum lipid concentrations were measured in all women. Additionally, 18 subjects underwent noninvasive assessment of central arterial stiffness using applanation tonometry. Fifty percent of subjects were hypertensive and a similar number had an abnormal echocardiogram. A bicuspid aortic valve was present in 33% of subjects, 16 women (42%) had ascending aortic root dilatation. This was associated with a bicuspid aortic valve in four women and hypertension in 11. Two women had isolated aortic root dilatation. Aortic root diameter was significantly associated with systolic blood pressure (r = 0.5, P = 0.003) and left ventricular thickness (r = 0.5, P = 0.02). There was no association with serum lipids or arterial compliance. Structural cardiac abnormalities are present in up to 50% of women with Turner's syndrome. Aortic root dilatation is a significant risk in women with Turner's syndrome and is closely dependent on blood pressure. Aortic root dilatation does not appear to be related to atherosclerosis and is more likely to be due to a mesenchymal defect. Regular surveillance of the aortic root diameter is essential in all women with Turner's syndrome and hypertension should be treated aggressively when present in order to minimize the risk of potentially fatal aortic dissection.

Urethral dilation in women: a questionnaire-based analysis of practice patterns

Objectives. To assess current practice patterns among urologists and to determine the perceived efficacy of urethral dilation. Urethral dilation has been advocated as a treatment for a variety of urologic disorders in women for several decades. Recent changes in Medicare reimbursement have again focused attention on this issue. Methods. A 15-item questionnaire was mailed to all urologists actively practicing in the state of Texas (n = 642). The questionnaire consisted of 12 items about indications for, technique of, and outcome of urethral dilation, and three demographic questions regarding location and type of practice and number of years since completing residency. Results. A total of 194 physicians completed and returned the questionnaire (30%). Overall, 48.2% of practitioners used dilation six or fewer times during the past year; 23.7% reported having used it more than 30 times. Most urologists used dilation for urethral syndrome only (61.1%), although urethral stricture was also a frequently reported condition requiring dilation (29%). Most urologists trained within the past decade (60.9%) reported never offering dilation for urethral syndrome; only 34.2% of the remainder never offered it ( P = 0.002). Urologists normally performed this procedure with local or no anesthesia (85%) and most commonly dilated to 32F (45%). Overall, 21% of urologists trained more than 10 years ago considered dilation very or extremely successful in treating urethral syndrome; 0 of 42 trained more recently considered it to be this successful ( P = 0.014). Conclusions. The use of urethral dilation in women remains controversial. Recently trained urologists use it less frequently and find it less efficacious than those who have been practicing for longer periods. Since such obvious biases exist, it is imperative that the clinical merit of urethral dilation be carefully scrutinized.

Non-invasive investigation of endothelium-dependent dilatation of the brachial artery in women with primary Raynaud's phenomenon.

1. Primary Raynaud's phenomenon is characterized by white fingers and toes with impaired perfusion in response to cold or emotional stress. The aetiology has not been clarified. In previous studies we have demonstrated a season-linked inability in women with primary Raynaud's phenomenon to raise their plasma cGMP levels in response to whole-body cooling, suggesting a dysfunction of the L-arginine-NO-cGMP pathway. To further elucidate the possibility of such a defect in patients with primary Raynaud's phenomenon, we determined flow-mediated dilatation of the brachial artery. 2. Twenty-two premenopausal, non-smoking women with primary Raynaud's phenomenon (mean age 39 +/- 8 years) and 23 healthy controls (mean age 41 +/- 7 years) were studied during two winter weeks. The diameter of the right arm brachial artery was measured by high resolution ultrasonography, at rest and during reactive hyperaemia. The investigation was conducted both with the participants at rest at room temperature and after 40 min of whole-body cooling. 3. Both study groups showed a marked attenuation of flow-mediated dilatation during whole-body cooling, which could partly but not solely be explained by a decreased shear rate. There was, however, no significant difference in flow-mediated diameter (D) increase (% flow-mediated dilatation; delta D/D x 100) between primary Raynaud's phenomenon and controls, either at room temperature (7.8 +/- 0.8 and 9.0 +/- 0.8) or in response to whole-body cooling (3.8 +/- 1.2 and 4.4 +/- 0.7). 4. Thus, whole-body cooling markedly impairs flow-mediated dilatation in women. Flow-mediated dilatation is, however, not decreased in women with primary Raynaud's phenomenon at room temperature or during whole-body cooling, indicating that this particular aspect of endothelial function is not impaired in this setting.

Does Passive Smoking Impair Endothelium-Dependent Coronary Artery Dilation in Women?

Objectives. This study sought to examine whether passive smoking is associated with endothelial dysfunction in the coronary arteries.Background. Long-term exposure to cigarette smoking has been reported to suppress endothelium-dependent arterial dilation in humans. Endothelial dysfunction is an early feature of atherogenesis, and the impairment of acetylcholine (ACh)-induced coronary artery dilation indicates coronary endothelial dysfunction.Methods. We studied 38 women (40 to 60 years old) who had no known risk factors for coronary artery disease other than tobacco smoking: 11 nonsmokers who had never smoked and had never been regularly exposed to environmental tobacco smoke; 19 passive smokers with self-reported histories of exposure to environmental tobacco smoke of ≥1 h/day for ≥10 years; and 8 active smokers. We examined the response of the epicardial coronary artery diameters (proximal and distal segments of the left anterior descending [LAD] and left circumflex [LCx] coronary arteries) to the intracoronary injection of ACh into the left coronary artery by means of quantitative coronary angiography.Results. ACh significantly dilated the distal segment in nonsmokers (percent change from baseline diameter: LAD 13.7 ± 3.4%, p < 0.05; LCx 18.8 ± 2.9%, p < 0.01) but not the proximal segment (LAD 7.4 ± 3.5%; LCx 3.1 ± 5.0%). ACh significantly constricted all segments of the left coronary artery in passive smokers (LAD: proximal −20.3 ± 3.7%, p < 0.05; distal −22.3 ± 4.1%, p < 0.01; LCx: proximal −20.8 ± 3.1%, p < 0.05; distal −17.3 ± 2.9%, p < 0.01) and active smokers (LAD: proximal −14.8 ± 3.4%, p < 0.05; distal −27.2 ± 6.0%, p < 0.01; LCx: proximal −14.5 ± 6.6%, p < 0.05; distal −22.4 ± 4.0%, p < 0.01). Thus, ACh constricted most coronary arteries in both passive and active smokers and dilated the coronary arteries in nonsmokers.Conclusions. Impairment of ACh-induced coronary artery dilation, indicating coronary endothelial dysfunction, may occur diffusely in passive smokers as well as in active smokers.

Application of vaginal misoprostol before cervical dilatation to facilitate first-trimester pregnancy interruption: Bugalho A.; Bique C.; Almeida L.; Bergstrom S. NOR Obstet Gynecol 1994 83/5 I (729–731)

To study the capacity of vaginal misoprostol to soften the cervix and facilitate cervical dilatation in women undergoing first-trimester pregnancy interruption.We performed a double-blind, placebo-controlled study in 100 women opting for voluntary pregnancy interruption. The subjects were randomly allocated to two treatment groups, receiving either 200 micrograms misoprostol or placebo in the posterior vaginal fornix 6 hours before cervical dilatation. We noted the number of women with vaginal bleeding, with chorionic tissue in the vagina, or with no resistance to a Hegar 8 dilator, and recorded the total time in minutes for pregnancy interruption.Vaginal bleeding from the cervix occurred in 70% of the misoprostol group and in 8% of the placebo group (odds ratio 26.83; 95% confidence interval [CI] 9.73-74.00). Almost one-fourth (22%) of the misoprostol-treated women had chorionic tissue in the vagina, compared to one woman (2%) in the placebo group (odds ratio 13.82; 95% CI 2.59-73.61). Cervical dilatation was achieved in 74 and 10% of the misoprostol- and placebo-treated women, respectively (odds ratio 25.62; 95% CI 9.61-68.28). The time required for pregnancy interruption was significantly shorter with misoprostol (P < .004).Misoprostol is significantly more effective in facilitating cervical dilatation than is placebo. The average intervention time for pregnancy interruption was reduced by 35%.

Bladder pillar block anesthesia for urethral dilatation in women

This report describes an adaptation of the bladder pillar block anesthetic technique for use during routine urethral dilatation for treatment of the urethral syndrome or urethral stenosis in women. Only 10% of patients experienced sufficient discomfort to require cessation of dilatation prior to reaching a calibration of 38 F.