Pial venous pressure and acute hypertensive disruption of the blood-brain barrier in spontaneous and renal hypertension

The purpose of this study was to determine whether changes in pial venous pressure during acute hypertension account for altered acute hypertensive disruption of the blood-brain barrier in chronic hypertension. We studied 13 normotensive WKY rats, 7 spontaneously hypertensive rats (SHR), and 9 two-kidney, one-clip renal hypertensive rats of the same age. Pial venous pressure (servonull technique) and clearance of fluorescein-labeled dextran from pial vessels (as an estimate of permeability of the blood-brain barrier) were measured before and during acute hypertension produced by i.v. infusion of phenylephrine. Experiments were performed in anesthetized rats (50 mg/kg sodium pentobarbital i.p.). Blood and artificial cerebrospinal fluid pO2, pCO2 and pH were within normal ranges throughout the experiment. The change, time to peak and peak pial venous pressures were the same in all groups. The peak arterial pressure after phenylephrine was greater in the hypertensive rats compared to WKY rats. The time to peak mean arterial pressure was the same in all groups of rats. Clearance of FITC dextran was the same in WKY versus renal hypertensive rats, but less in SHR versus WKY rats (P less than 0.05 by analysis of variance). We conclude that something other than an attenuation of the increase in pial venous pressure protects the blood-brain barrier of SHR against acute hypertensive disruption.     

The incidence and prevalence of idiopathic intracranial hypertension in Sheffield,UK

Background and purpose: The purpose of this study was to identify the incidence and prevalence of idiopathic intracranial hypertension (IIH) in Sheffield, UK. Methods: A retrospective review of case notes was conducted to identify cases of IIH seen between 1 January 2007 and 31 December 2008. Results: Sixteen (15 women and 1 man) new patients were identified to give an incidence within Sheffield of 1.56/100 000/year and 2.86/100 000/year for women. The incidence of IIH in obese women was 11.9/100 000/year. The prevalence of IIH was calculated as 10.9/100 000, and 85.7/100 000 in obese women. Conclusion: A higher incidence of IIH than previously reported UK data was found, which may be because of increasing obesity within the population, or improved case ascertainment.     

Baroreflex sensitivity in essential and secondary hypertension

Baroreceptor reflex regulation has been shown to reset towards a higher blood pressure level and to operate with reduced sensitivity in hypertension. Whether this is secondary to elevated blood pressure or whether it plays a role in the development of hypertension is not known. In addition, only limited data exist on baroreflex sensitivity (BRS) in patients with long-lasting medically treated essential hypertension and in patients who have blood pressure elevation with similar severity, but of different etiology. The purpose of this study was to examine BRS in patients with different severity and forms of chronic, medically treated hypertension. Patients with renovascular hypertension (RVHT, n = 14), severe essential hypertension (SEHT, n = 36) and mild essential hypertension (MEHT, n = 29) as well as healthy age- and sex-matched control subjects were studied. BRS was measured with the phenylephrine method. BRS in the RVHT (3.7 ± 0.6 ms/mmHg) and SEHT (7.6 ± 0.8 ms/mmHg) groups did not differ from each other after age, gender and left ventricular mass index were taken into consideration. On the contrary, BRS in the RVHT (p = 0.008) and SEHT (p = 0.016) groups were lower than in the MEHT (8.5 ± 1.2 ms/mmHg) group. BRS was also significantly reduced in the RVHT (P = 0.004) and SEHT groups (P = 0.006) when compared to the healthy age- and sex-matched controls. BRS in the MEHT group did not differ from the control subjects. In conclusion, BRS was equally impaired in patients with renovascular and severe essential hypertension, which was similar in severity but different in etiology. BRS in patients with long-lasting medically treated mild essential hypertension did not differ from the healthy subjects. Our study suggests that baroreflex dysfunction in hypertensive patients is related to the clinical severity of hypertension, rather than its etiology. Received: 12 April 2001, Accepted: 11 September 2002 Correspondence to Hanna Mussalo, MD     

Sudden re-opening of collapsed transverse sinuses and longstanding clinical remission after a single lumbar puncture in a case of idiopathic intracranial hypertension. Pathogenetic implications

Abstract The aetiopathogenetic role of sinus venous obstructions carried by most idiopathic intracranial hypertension (IIH) patients is controversial. We report the case of a young woman diagnosed with IIH with papilloedema and narrowing of transverse sinuses, in which lowering of intracranial pressure by a single 20 ml cerebrospinal fluid (CSF) resulted in a strong dimensional increase of the transverse sinuses. Changes were followed by clinical remission and normalisation of optical nerve calibre, maintained after a 2-month follow-up. Our findings indicate that, although secondary to CSF hypertension, venous sinuses compression may have an important role in hypertensive status maintenance. Pathogenetic implications of venous sinus compression by hypertensive CSF in IIH are discussed.     

高血压脑出血内外科规范化治疗的疗效比较—多中心随机前瞻性研究

目的:评价高血压脑出血内、外科规范化治疗的疗效。方法:多中心前瞻性、随机对照比较内外科规范化治疗的效果。结果:外科组２６６例,内科组２３４例。按Ｌｏｇｉｓｔｉｃ模型统计,外科组近期和远期疗效明显优于内科组。外科组近期死亡率９．８%,远期死亡率１１．８%,并发症发生率均低于内科组。结论:高血压脑出血外科规范化治疗疗效优于内科规范化治疗。     

Is there a difference in outcomes of patients with idiopathic intracranial hypertension with the choice of cerebrospinal fluid diversion site: a single centre experience

The visual and headache outcomes in patients with idiopathic intracranial hypertension (IIH) undergoing cerebrospinal fluid diversion with a lumboperitoneal (LPS) or ventriculoperitoneal shunting (VPS) have not been well reported. The aims of this study were to: (a) to assess outcomes of CSF diversion in IIH, (b) to understand influence of the type of shunt in outcomes, and (c) to understand factors predisposing in shunt failure.

Methods

The medical records of 34 patients who underwent cerebrospinal fluid diversion (CSFD) between 1996 and 2007 were retrieved and epidemiological and clinical data was collected.

Results

The mean age was 35 (±7.9) years. Thirty-four patients underwent 63 shunt placements in total. 85% follow-up was achieved. The mean follow-up for the entire group was 28.9 (±31.8) months. Headaches improved more than visual disturbances. There was no significant difference between the groups that received a VPS and those receiving an LPS in both headache and visual outcomes. The rate of complications was 20.5% and the need for revision was 35% for the whole group. Patients with LPS suffered more complications and first time revisions than patients with VPS. No factor recorded could predict the need for revision or final outcomes. The shunts of patients receiving a VPS tend to survive longer than those receiving primarily an LPS, however the difference is not statistically significant.

Conclusions

Predicting which patients will improve is not possible at present. The influence of site diversion is not critical but patients with VPS have less complications and revisions than those receiving a LPS.     

The effects of carbon dioxide on measuring cerebral spinal fluid pressure

Purpose  The effects of pCO2 on cerebral spinal fluid (CSF) pressure measurement were observed in four patients. Methods  Children presenting with either a diagnosis or suspected diagnosis of IIH, who were undergoing lumbar puncture under a general anaesthetic for pressure measurement, were recruited to study the relationship between pCO2 and CSF pressure measurements. Results  A rise of end-tidal pCO2 by 1 kPa causes a rise of CSF pressure by 3.5–12 cmH20. Conclusion  Controlling of pCO2 is important when measuring CSF pressure to prevent misdiagnosis and over treatment of patients with idiopathic intracranial hypertension (IIH).     

Arterial hypertension and ischaemic stroke

OBJECTIVES : Arterial hypertension is, besides age, the number one risk factor for ischaemic stroke. Patients with arterial hypertension frequently present with additional coexisting vascular risk factors interacting in a complex way. MATERIAL AND METHODS : This paper reviews the benefit of antihypertensive treatment, as well as different treatment options of arterial hypertension and their side-effects. RESULTS : Patients with definite arterial hypertension, but also patients with so-called normal or high-normal blood pressure are at increased risk to develop stroke and other cardiovascular complications. Vascular remodelling of small and large vessels provoked by arterial hypertension is the initial step in the development of atherosclerosis and lipohyalinosis. Vascular remodelling can be improved or even normalized by antihypertensive treatment with angiotensin-converting-enzyme inhibitors and angiotensin-I-receptor antagonists showing the most convincing effects. Angiotensin-converting-enzyme inhibitors and angiotensin-I-receptor antagonists have the lowest rate of side-effects, however, economic restraints hinder their general application. Statins are needed to treat dyslipidaemia. They also lower blood pressure and have a synergistic effect with the above two antihypertensive components in lowering blood pressure. In hypertensive patients, risk of stroke and other cardiovascular complications is determined by the blood pressure level and the presence or absence of target organ damage and the interaction with other risk factors, such as cigarette smoking, dyslipidaemia, and diabetes. These high-risk patients should be treated even more aggressively than usual. CONCLUSIONS : In the vast majority of patients and healthy individuals, target blood pressure should be as high as or below 120/80 mmHg to minimize the occurrence of stroke and other cardiovascular complications.     

收缩期高血压与脑血栓形成的关系

高血压、高脂血症、糖尿病、吸烟及肥胖是公认的心脑血管病的危险因素，近年发现高同型半胱氨酸（Hcy）血症也是心脑血管病的危险因素。本研究纳入血浆Hcy．在研究了高血压、高脂血症等诸因素后，发现收缩期高血压与脑血栓形成有关。[第一段]     

Predicting factors of depression in patients with primary hypertension: a community-based study

OBJECTIVE To investigate the factors that may predict the occurrence of depression in patients with primary hypertension.

METHODS We conducted a cross-sectional survey on 891 hypertensive patients and 651 normal subjects (control group) from a single community. Zung self-rating depression scale (SDS) was applied to evaluate the symptoms of depression, which was diagnosed when the SDS score was >41.

RESULTS There was no significant difference in gender distribution (female, 48.5 vs. 47.6%) and age (65.3±9.2 vs. 64.0±7.9 years) between the hypertensive control groups (P>0.05). Depression was diagnosed in 139 hypertensive patients (15.6%) and 27 (4.2%) control subjects (P<0.01). The average SDS score was higher in patients with hypertension duration of more than 3 years (33.3±9.0 vs. 30.6±7.6, P<0.001), in patients with severe hypertension (44.0±7.8 vs. 28.9±4.9, P<0.001) and in patients with a history of hospitalization for cardiovascular disorders (38.1±9.3 vs. 32.0±8.4, P<0.001). Multivariate regression analysis showed that the degree and the duration of hypertension, as well as hospitalization history, were independent predictors of depression in the hypertensive patients.

CONCLUSIONS Hypertension is associated with a higher prevalence of depression that can be predicted by the duration and severity of hypertension as well as a history of hospitalization.     

Possible melatonin involvement in the hypotensive effect of MAO inhibitors

Summary Effect of selective inhibitors of MAO-A and B isoenzymes on pineal melatonin (and related indoles), arterial blood pressure and brain MAO-A and B activities has been evaluated in intact, pinealectomized and shamoperated rats.Selective inhibition of MAO-A but not MAO-B activity stimulated pineal melatonin synthesis and decreased arterial blood pressure in intact and sham-operated animals. Pinealectomy attenuated the hypotensive effect of MAO-A inhibition.The possible melatonin contribution to both antidepressive and hypotensive effects of MAO inhibitors is discussed.     

Idiopathic intracranial hypertension in pregnancy

Objective Since idiopathic intracranial hypertension (IIH) is most prevalent in obese women of childbearing age, concerns arise regarding the impact of pregnancy on the disorder and the potential teratogenicity of some therapeutic agents. We evaluated the course, management of pregnant IIH patients and the visual and pregnancy outcomes. Methods Case series of pregnant women diagnosed with IIH. IIH symptoms, neuro-ophthalmological findings, IIH management, visual and pregnancy outcomes were documented. Results Among 240 women with IIH, 12 had 16 pregnancies. Ten had headaches, five had transient visual obscurations, and three had diplopia. Visual acuity was severely decreased in one and mildly reduced in three women. Six had marked and six had mild bilateral papilledema. Visual field loss occurred in four women. Visual symptoms and loss improved for the duration of the pregnancy after diagnostic lumbar puncture and salt restricted diet in three. Two additional women needed continuous spinal drainage for two days. One woman was treated with acetazolamide and medical abortion. The one woman with severe vision loss had fenestration of one optic nerve sheath and a lumboperitoneal shunt as well as corticosteroids and was the only case with permanent field loss. After intervention, visual acuity improved in all cases with reduced vision. There were 10 full-term normal deliveries, three missed abortions, one therapeutic abortion and two intrauterine fetal deaths. Conclusions IIH appears to present during the first two trimesters of pregnancy with typical symptoms and findings. Visual outcome is similar as for non-pregnant women. Treatment should be oriented towards dietary control, without ketosis. Repeated spinal fluid drainage, if needed, can be helpful. Received: 29 November 2001 Received in revised form: 14 February 2002 Accepted: 18 February 2002     

Impaired cerebral vasoreactivity in white coat hypertensive adolescents

Background and purpose: Although its incidence is not high, adolescent hypertension may predict hypertension and increased cardiovascular risk in adulthood. Therefore, the aim of the present study was to assess whether cerebrovascular reactivity is altered in adolescent white coat and sustained hypertensive patients compared to healthy teenagers. Methods: Fifty‐nine normotensive, 47 white coat hypertensive (WCH), and 73 sustained hypertensive (SH) adolescents were studied. WCH and SH were differentiated by ambulatory blood pressure monitoring. Cerebrovascular reactivity was assessed by transcranial Doppler breath‐holding test and was expressed in percent (%) change to the resting cerebral blood flow velocity value. Results: The percent increase in middle cerebral artery mean blood flow velocity after 30 s of breath holding was lower in both WCH (5.3 ± 3.1%) and SH (9.5 ± 2.6%) groups indicating lower vasodilatory reactivity compared to healthy adolescents (12.1 ± 2.2%). Additionally, serum nitric oxide (NOx) concentrations were lower in both WCH (30.6 ± 11 μM) and SH (30.7 ± 22.4 μM) groups compared to controls (38.8 ± 7.6 μM). Conclusions: Both white coat and sustained hypertension result in decreased vasodilatory reaction to CO₂ in adolescents, suggesting involvement of the cerebral arterioles. The present study underlines the importance of early recognition and proper treatment of adolescent hypertension in order to prevent long‐term cardiovascular complications.     

Blood Pressure in Acute Ischemic Stroke

Hypertension is present in up to 84% of patients presenting with acute stroke, and a smaller proportion of patients have blood pressures that are below typical values in the context of cerebral ischemia. Outcomes are generally worse in those who present with either low or severely elevated blood pressure. Several studies have provided valuable information about malignant trends in blood pressure during the transition from the acute to the subacute phase of stroke. It is not uncommon for practitioners in clinical practice to identify what appear to be pressure-dependent neurologic deficits. Despite physiologic and clinical data suggesting the importance of blood pressure modulation to support cerebral blood flow to ischemic tissue, randomized controlled trials have not yielded robust evidence for this in acute ischemic stroke. We highlight previous studies involving acute-stroke patients that have defined trends in blood pressure and that have evaluated the safety and efficacy of blood-pressure modulation in acute ischemic stroke. This overview reports the current status of this topic from the perspective of a stroke neurologist and provides a framework for future research.