scholarly journals Deletion of type VIII collagen reduces blood pressure, increases carotid artery functional distensibility and promotes elastin deposition

2021 ◽  
Vol 12 ◽  
pp. 100085
Author(s):  
Amanda L. Mohabeer ◽  
Jeffrey T. Kroetsch ◽  
Meghan McFadden ◽  
Negin Khosraviani ◽  
Thomas J. Broekelmann ◽  
...  
2018 ◽  
Vol 69 (6) ◽  
pp. 1550-1553
Author(s):  
Rosana Manea ◽  
Bianca Elena Popovici ◽  
Carmen Daniela Neculoiu ◽  
Dan Minea ◽  
Alina Calin

Hypertension is a major risk factor for progression of the atherosclerotic process and for developing of degenerative cardiovascular diseases in adulthood. The aim of this study is to evaluate how the measurement of carotid intima - media thickness for prediction of essential hypertension in children can be used.The study group included 81 children and the control group 61 children, all aged between 5 - 17 years and 11 months old, and admitted in Children Hospital Brasov in the period of 2009 � 2014. The study protocol included: BMI, blood pressure and Doppler echography of the common carotid artery for each group. Mean age of the patients from the study group was 13.67 years, 43.20 % girls and 56.80 % boys, while in the control group, the mean age was 14.07 years, 54.10% girls and 45.90 % boys. 70.37% of the children from the study group presented obesity, while in the control group 40.98% were obese. The IMTC study group ranged from 0.52 - 0.69 mm and the limits of the normotensive subjects were 0.32 -0.54 mm. In both groups the obese patients were found to have increased carotid artery intima-media, which means that IMTC was positively correlated with BMI (p=0.000001).It is necessary to identify diagnostic methods easily applicable for children, allowing involvement of the characteristics of the arterial wall in the degenerative pathological processes. Increased intima-media ratio is positively correlated with high values of blood pressure.


2015 ◽  
Vol 26 (7) ◽  
pp. 1333-1342 ◽  
Author(s):  
Thacira D. A. Ramos ◽  
Tatianne M. E. Dantas ◽  
Mônica O. S. Simões ◽  
Danielle F. Carvalho ◽  
Carla C. M. Medeiros

AbstractObjectiveTo evaluate the presence of carotid thickening and its relationship with the Pathobiological Determinants of Atherosclerosis in Youth score.MethodsWe carried out a cross-sectional study involving 512 brazilian adolescents. Variables such as sex, body mass index, concentrations of non-high-density lipoprotein and high-density lipoprotein cholesterol, blood pressure, blood glucose and glycated haemoglobin A1c levels that make up the score, and carotid thickening through the intima-media complex measured by ultrasound were evaluated. We adopted two cut-off points to evaluate carotid thickening, being considered altered for those higher or equal to the z-score 2+ and ⩾75th percentile. The association was assessed using the χ2 test and univariate and multivariate logistic regression analyses.ResultsHigh cardiovascular risk was present in 10.2% of the adolescents; carotid thickness was present in 4.3% determined by the z-score 2+ and in 25.0% determined by the 75th percentile. When measured by the z-score, carotid thickening was associated with high systolic blood pressure (p=0.024), high-non-high density lipoprotein cholesterol (p=0.039), and high cardiovascular risk assessed by the score and by the 75th percentile, with body mass index >30 (p=0.005). In the multivariate analysis, high cardiovascular risk was found to be independently associated with the presence of carotid thickness evaluated by the z-score, with risk four times greater (p=0.010) of presenting with this condition compared with individuals with low risk, and this fact was not observed when factors were analysed alone.ConclusionThe presence of high cardiovascular risk in adolescents assessed by the Pathobiological Determinants of Atherosclerosis in Youth score was associated with marked thickening of the carotid artery in healthy adolescents.


2019 ◽  
Vol 130 (5) ◽  
pp. 1468-1477 ◽  
Author(s):  
David Hasan ◽  
Mario Zanaty ◽  
Robert M. Starke ◽  
Elias Atallah ◽  
Nohra Chalouhi ◽  
...  

OBJECTIVEThe overall risk of ischemic stroke from a chronically occluded internal carotid artery (COICA) is around 5%–7% per year despite receiving the best available medical therapy. Here, authors propose a radiographic classification of COICA that can be used as a guide to determine the technical success and safety of endovascular recanalization for symptomatic COICA and to assess the changes in systemic blood pressure following successful revascularization.METHODSThe radiographic images of 100 consecutive subjects with COICA were analyzed. A new classification of COICA was proposed based on the morphology, location of occlusion, and presence or absence of reconstitution of the distal ICA. The classification was used to predict successful revascularization in 32 symptomatic COICAs in 31 patients, five of whom were female (5/31 [16.13%]). Patients were included in the study if they had a COICA with ischemic symptoms refractory to medical therapy. Carotid artery occlusion was defined as 100% cross-sectional occlusion of the vessel lumen as documented on CTA or MRA and confirmed by digital subtraction angiography.RESULTSFour types (A–D) of radiographic COICA were identified. Types A and B were more amenable to safe revascularization than types C and D. Recanalization was successful at a rate of 68.75% (22/32 COICAs; type A: 8/8; type B: 8/8; type C: 4/8; type D: 2/8). The perioperative complication rate was 18.75% (6/32; type A: 0/8 [0%]; type B: 1/8 [12.50%]; type C: 3/8 [37.50%], type D: 2/8 [25.00%]). None of these complications led to permanent morbidity or death. Twenty (64.52%) of 31 subjects had improvement in their symptoms at the 2–6 months’ follow-up. A statistically significant decrease in systolic blood pressure (SBP) was noted in 17/21 (80.95%) patients who had successful revascularization, which persisted on follow-up (p = 0.0001). The remaining 10 subjects in whom revascularization failed had no significant changes in SBP (p = 0.73).CONCLUSIONSThe pilot study suggested that our proposed classification of COICA may be useful as an adjunctive guide to determine the technical feasibility and safety of revascularization for symptomatic COICA using endovascular techniques. Additionally, successful revascularization may lead to a significant decrease in SBP postprocedure. A Phase 2b trial in larger cohorts to assess the efficacy of endovascular revascularization using our COICA classification is warranted.


Hypertension ◽  
2016 ◽  
Vol 68 (suppl_1) ◽  
Author(s):  
Lyndsey E DuBose ◽  
Seth W Holwerda ◽  
Amy K Stroud ◽  
Nealy A Wooldridge ◽  
Janie E Myers ◽  
...  

Older age is associated with elevated large elastic artery stiffness, a strong predictor of cardiovascular (CVD) risk in middle-age/older (MA/O) adults independent of blood pressure (BP). Greater 24-hour systolic BP variability (BPV) is also an independent risk factor for CVD and is linked to large artery stiffness in MA/O adults with hypertension and diabetes. However, its relation to age-related arterial stiffness in adults with low risk factor burden is unclear. We hypothesized that higher systolic BPV would be: 1) associated with advancing age, and 2) related to elevated aortic and carotid artery stiffness among healthy MA/O adults. To determine this, 98 healthy adults (ages 19-70 yrs) with measurements of systolic BPV (standard deviation of 24 hr systolic BP) via ambulatory BP monitoring, aortic stiffness (carotid-femoral pulse wave velocity, cfPWV), carotid artery stiffness (β-stiffness via carotid tonometry/B mode ultrasound) and circulating metabolic factors were included. In the entire cohort, greater systolic BPV was not associated with age, cfPWV, carotid β stiffness or circulating lipids/glucose (all P>0.05), but was correlated (age-adjusted) with 24 hr systolic BP (r= 0.41, P<0.001) and BMI (r= 0.21, P<0.05). In stepwise linear regression analyses that included age, sex, BMI, only 24 hr systolic BP was associated with systolic BPV (β= 0.14 ± 0.03, Model R 2 = 0.20, P< 0.001). Interestingly, there was no difference in 24 hr systolic BPV (11.4 ± 0.4 vs 11.4 ± 0.5 SD mmHg, P=0.99) in young (n=55; 29.0 ± 0.7 yrs) vs. MA/O (n= 43; 53.0 ± 1.2 yrs) adults despite higher cfPWV (594 ± 12 vs 913 ± 39 cm/sec, P<0.001), carotid β-stiffness (6.8 ± 0.6 vs 9.3 ±0.9 U, P=0.001) and 24 hr systolic BP (121 ± 1 vs 125 ± 2 mmHg, P<0.05). Systolic BPV was associated with BMI (r= 0.42, p< 0.01) and fasting blood glucose (r= 0.54, P= 0.001) in MA/O but not young adults. In a stepwise linear regression model among MA/O, 24 hr systolic BP (β= 0.18 ± 0.04, R 2 = 0.36, P<0.001) and fasting glucose (β= 0.10 ± 0.05, R 2 change= 0.07, P<0.001) were the only significant correlates of systolic BPV (Model R 2 = 0.43, P<0.001). In conclusion, 24 hr systolic BP and fasting blood glucose, but not age or large elastic artery stiffness, were the strongest determinants of higher systolic BPV in normotensive MA/O adults.


Author(s):  
Juulia Lantto ◽  
Tiina Erkinaro ◽  
Mervi Haapsamo ◽  
Heikki Huhta ◽  
Leena Alanne ◽  
...  

A drop in arterial oxygen content activates fetal chemoreflex including an increase in sympathetic activity leading to peripheral vasoconstriction and redistribution of blood flow to protect the brain, myocardium, and adrenal glands. By using a chronically instrumented fetal sheep model with intact placental circulation at near-term gestation, we investigated the relationship between peripheral chemoreflex activation induced by hypoxemia and central hemodynamics. 17 Åland landrace sheep fetuses at 115-128/145 gestational days were instrumented. Carotid artery was catheterised in 10 fetuses and descending aorta in 7 fetuses. After a 4-day recovery, baseline measurements of fetal arterial blood pressures, blood gas values, and fetal cardiovascular hemodynamics by pulsed Doppler ultrasonography were obtained under isoflurane-anesthesia. Comparable data to baseline was collected 10 (acute hypoxemia) and 60 minutes (prolonged hypoxemia) after maternal hypo-oxygenation to saturation level of 70-80% was achieved. During prolonged hypoxemia, pH and base excess (BE) were lower, and lactate levels higher in the descending aorta than in the carotid artery. During hypoxemia mean arterial blood pressure (MAP) in the descending aorta increased, while in the carotid artery MAP decreased. In addition, right pulmonary artery pulsatility index values increased, and the diastolic component in the aortic isthmus blood flow velocity waveform became more retrograde. Both fetal ventricular cardiac outputs were maintained even during prolonged hypoxemia when significant fetal metabolic acidemia developed. Fetal chemoreflex activation induced by hypoxemia decreased the perfusion pressure in the cerebral circulation. Fetal weight-indexed LVCO or AoI Net Flow-ratio did not correlate with a drop in carotid artery blood pressure.


Author(s):  
Arron Peace ◽  
Virginia Pinna ◽  
Friso Timmen ◽  
Guillherme Speretta ◽  
Helen Jones ◽  
...  

Abstract Objectives Carotid artery diameter responses to sympathetic stimulation, i.e., carotid artery reactivity (CAR), represent a novel test of vascular health and relates to cardiovascular disease (CVD)/risk. This study aims to understand the relationship between the increase in blood pressure and carotid artery diameter response during the CAR-test in healthy, middle-aged men. Methods Sample consisted of 40 normotensive men (aged 31–59 years) with no history of CVD of currently taking medication. Noninvasive ultrasound was used to measure carotid artery diameter during the cold pressor test (CPT), with CAR% being calculated as the relative change from baseline (%). Mean arterial pressure (MAP) was measured with beat-to-beat blood pressure recording. Results CAR% was 4.4 ± 5.4%, peaking at 92 ± 43 seconds. MAP increased from 88 ± 9 mmHg to 110 ± 15 mmHg, peaked at 112 ± 38 seconds, which was significantly later than the diameter peak (P = 0.04). The correlation between resting MAP and CAR% was weak (r = 0.209 P = 0.197). Tertiles based on resting MAP or MAP-increase revealed no significant differences between groups in subject characteristics including age, body mass index, or CAR% (all P > 0.05). Subgroup analysis of individuals with carotid constriction (n = 6) vs. dilation (n = 34), revealed no significant difference in resting MAP or increase in MAP (P = 0.209 and 0.272, respectively). Conclusion Our data suggest that the characteristic increase in MAP during the CPT does not mediate carotid artery vasomotion.


1962 ◽  
Vol 202 (6) ◽  
pp. 1244-1246
Author(s):  
James G. Hilton

The effects of infusion of epinephrine to a fixed maintained blood pressure level, after blockade of the ganglia by the administration of hexamethonium, on the blood pressure responses to histamine have been studied in the dog anesthetized by the intravenous injection of 30 mg/kg of pentobarbital sodium. The blood pressure levels maintained by the infusion of epinephrine were 100, 130, and 160 mm Hg. The doses of histamine tested were 1.0, 5.0, and 10.0 µg/kg. Blood pressure was measured from the carotid artery by means of a mercury manometer. Following each dose of histamine during the control period and at each infusion-maintained blood pressure level the blood pressure responses were analyzed in terms of minimum attained blood pressure, actual fall in blood pressure (depressor response), and duration of fall in blood pressure. The results of these experiments have shown that the depressor response to histamine is not affected by the blockade of the ganglia or the infusion of epinephrine. The minimum attained blood pressure is directly related to the level of the blood pressure at the time of the histamine administration and therefore a function of the quantity of epinephrine infused. From these results it has been concluded that epinephrine is not antagonistic to the histamine depressor response, but will alter the minimum blood pressure through its effects on the preinjection control blood pressure.


2020 ◽  
Vol 245 (11) ◽  
pp. 977-982
Author(s):  
You Kyoung Shin ◽  
Yu Shan Hsieh ◽  
A Young Han ◽  
Soonho Kwon ◽  
Geun Hee Seol

Excessive dietary fat intake is related to metabolic dysfunction and enhances susceptibility to hypertension and cognitive impairment. Although there are sex differences in the prevalence and progression of these diseases, few studies have investigated sex differences in cardio-metabolic and cognitive parameters in rats with high-fat diet-induced metabolic dysfunction. To better reflect actual clinical conditions, sex-differences in rats with high-fat diet-induced metabolic dysfunction were evaluated. Male and female Sprague-Dawley rats were fed a high-fat diet to induce metabolic dysfunction and intraperitoneally injected with N-nitro-L-arginine methyl ester and scopolamine to model vulnerability to hypertension and cognitive impairment, respectively, whereas control rats were fed a regular diet and treated with distilled water and 0.9% saline. Male experimental rats showed significantly higher systolic blood pressure than female experimental animals. More importantly, acetylcholine-induced relaxation of carotid arteries was decreased only in the male experimental rats, revealing a significant difference compared with female experimental rats. These findings provide evidence for individualized sex-based management of patients with metabolic dysfunction and susceptibilities to hypertension and cognitive impairment. Impact statement Excessive dietary fat intake plays important roles in the process of metabolic dysfunction and increases susceptibilities to chronic diseases such as hypertension. Few previous studies, however, have accurately reflected real-world medical conditions. In addition, studies performed to date have not examined detailed sex-differences in cardio-metabolic and cognitive parameters, precluding the development of sex-tailored interventions for patients with metabolic dysfunction who are susceptible to hypertension and cognitive impairment. In this study, using rats with HFD-induced metabolic dysfunction that made them susceptible to hypertension and cognitive impairment, we demonstrate that male rats show greater impairment of acetylcholine-induced vasorelaxation of the carotid artery and systolic blood pressure compared to female rats. These findings may provide a basis for the early detection of carotid artery dysfunction and systolic blood pressure increase, especially in males.


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