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Mean BP (mean + bp)
Selected AbstractsStriatal dopamine D2 receptor availability in OCD with and without comorbid social anxiety disorder: preliminary findings,DEPRESSION AND ANXIETY, Issue 1 2008Franklin R. Schneier M.D. Abstract Dopamine D2 receptor availability in the striatum has been reported to be low in generalized social anxiety disorder (GSAD) and obsessive,compulsive disorder (OCD), but it has not been studied in persons with comorbid OCD and GSAD (OCD+GSAD). D2 receptor availability was assessed in 7 subjects with OCD+GSAD, 8 with OCD, and 7 matched healthy comparison (HC) subjects, all unmedicated adults. D2 receptor availability was assessed with single-photon emission computerized tomography (SPECT) to measure binding potential (BP) of the D2 receptor radiotracer [123I] iodobenzamide ([123I]IBZM). Mean striatal [123I]IBZM BP was significantly lower in the OCD+GSAD group (72.58 mL/g, SD=18.17) than in the HC group (118.41 mL/g, SD=45.40; P=.025). Mean BP in the OCD group (93.08 mL/g, SD=36.90) did not differ significantly from the HC group (P=.247). Trait detachment, as measured by the Detachment subscale of the Karolinska Scales of Personality, was negatively correlated with D2 availability across all subjects (rs=,.55, P=.013). Comorbid GSAD and OCD may be associated with decreased availability of D2 receptors in the striatum, consistent with prior findings in GSAD. Prior findings of decreased D2 receptor availability in noncomorbid OCD were not confirmed. Decreased D2 receptor availability was also associated with trait detachment, supporting prior findings in samples of healthy subjects. Depression and Anxiety 0:1,7, 2007. Published 2007 Wiley-Liss, Inc. [source] Inhibitory Effects Of Angiotensin Ii On Barosensitive Rostral Ventrolateral Medulla Neurons Of The RatCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 12 2001Delphine Bertram SUMMARY 1. The brain renin,angiotensin system can influence arterial baroreceptor reflex control of blood pressure (BP) through both direct and indirect effects on sympathetic premotor neurons of the rostral ventrolateral medulla (RVLM). The present study examined the direct effect of angiotensin (Ang) II applied by microiontophoresis on the ongoing activity of single RVLM neurons. 2. In 26 urethane-anaesthetized Wistar rats, recordings of single unit activities of barosensitive RVLM neurons were made from one barrel of a six-barrel micropipette assembly. The other five barrels were filled with either L -glutamate, AngII, valsartan (an AT1 receptor antagonist), PD 123177 (an AT2 receptor antagonist) and saline. All drugs were applied by microiontophoresis. 3. Mean BP was 83 ± 3 mmHg. Application of AngII inhibited the ongoing activity of RVLM neurons, identified as barosensitive because their activity was inhibited by a phenylephrine- induced increase in BP, from 12.6 ± 1.5 to 5.4 ± 1.1 Hz (n = 24; P < 0.001). Angiotensin II also inhibited the glutamate-evoked excitation of barosensitive RVLM neurons from 15 ± 3 to 5.8 ± 2.0 Hz (n = 6; P < 0.001). Valsartan significantly increased neuronal activity from 9.5 ± 2.3 to 13.5 ± 3.2 Hz (n = 7, P < 0.01), whereas PD 123177 significantly decreased neuronal activity from 13.5 ± 3.5 to 9.9 ± 2.8 Hz (n = 13; P < 0.01). 4. The results suggest that AngII exerts a tonic inhibitory effect on barosensitive RVLM neurons, which is presumably mediated through AT1 receptor stimulation. [source] Linear and nonlinear measures of blood pressure variability: Increased chaos of blood pressure time series in patients with panic disorderDEPRESSION AND ANXIETY, Issue 2 2004Vikram K. Yeragani M.B.B.S. Abstract Arterial blood pressure (BP) variability increases progressively with the development of hypertension and an increase in BP variability is associated with end organ damage and cardiovascular morbidity. On the other hand, a decrease in heart rate (HR) variability is associated with significant cardiovascular mortality. There is a strong association between cardiovascular mortality and anxiety. Several previous studies have shown decreased HR variability in patients with anxiety. In this study, we investigated beat-to-beat variability of systolic and diastolic BP (SBP and DBP) in normal controls and patients with panic disorder during normal breathing and controlled breathing at 12, and 20 breaths per minute using linear as well as nonlinear techniques. Finger BP signal was obtained noninvasively using Finapres. Standing SBPvi and DBP BPvi (log value of BP variance corrected for mean BP divided by HR variance corrected for mean HR) were significantly higher in patients compared to controls. Largest Lyapunov exponent (LLE) of SBP and DBP, a measure of chaos, was significantly higher in patients in supine as well as standing postures. The ratios of LLE (SBP/HR) and LLE (DBP/HR) were also significantly higher (P < .001) in patients compared to controls. These findings further suggest dissociation between HR and BP variability and a possible relative increase in sympathetic function in anxiety. This increase in BP variability may partly explain the increase in cardiovascular mortality in this group of patients. Depression and Anxiety 19:85-95, 2004. © 2004 Wiley-Liss, Inc. [source] Arterial stiffness in relation to subclinical atherosclerosisEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 1 2009A. Wykretowicz ABSTRACT Background, Increased arterial stiffness or arteriosclerosis, represents a physiological part of ageing. Atherosclerosis is a process that does not affect the arterial bed uniformly but has a variable local distribution and is frequently superimposed on stiffened vessels. We therefore addressed the question of whether any correlation exists between the general characteristics of arterial stiffness or wave reflection and subclinical atherosclerosis as assessed by carotid intima-media thickness (IMT) in a sample of healthy subjects. Methods, A total of 116 healthy subjects (mean age 55 years, 43 female) were evaluated. Arterial stiffness and wave reflection was assessed with the use of digital volume pulse analysis (DVP) and pulse wave analysis (PWA). Subclinical atherosclerosis was assessed by measurement of IMT. Results, Stiffness Index (SIDVP), the measure of general arterial stiffness correlated significantly with IMT (r = 0·37, P < 0·01). IMT correlated significantly with age (r = 0·5, P < 0·0001), waist to hip ratio (WHR) (r = 0·39, P < 0·0001) and mean blood pressure (BPmean) (r = 0·4, P < 0·0001). IMT did not correlate with measures of wave reflection. SIDVP correlated significantly with age (r = 0·32, P < 0·005), WHR (r = 0·36, P < 0·0001), BPmean (r = 0·36, P < 0·0001) and measurements of wave reflection. However analysis of a model which included variables that significantly influenced SIDVP and IMT, such as age, WHR and mean BP showed that arterial stiffness is not independently associated with subclinical atherosclerosis. Conclusions, The indices of subclinical atherosclerosis, arterial stiffness and wave reflection, indicate different aspects of vascular status in otherwise healthy subjects [source] Acute Blood Pressure Changes After the Onset of Atrioventricular Nodal Reentrant Tachycardia: A Time-Course AnalysisJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2005MEHDI RAZAVI M.D. Introduction: We aimed to characterize blood pressure (BP) response at the beginning of atrioventricular nodal reentrant tachycardia (AVNRT) and its relationship to orthostatic challenge and variable atrioventricular interval. Methods and Results: In this prospective study of 17 consecutive patients with documented AVNRT, mean BP was analyzed in the supine and upright positions during sinus rhythm, AVNRT, and pacing with atrioventricular delay of 150 msec (AV150) and 0 msec (AV0). Mean BPs were compared at 3,5 seconds, 8,10 seconds, and 28,30 seconds after the onset of AVNRT or pacing. BP decreased immediately after AVNRT initiation, with gradual recovery during the first 30 seconds from 71.9 ± 16.5 mmHg to 86 ± 13.8 mmHg, P < 0.01. A similar pattern was observed during AV0, but not during AV150, pacing. While supine, mean BP decrease was more pronounced during AVNRT and AV0 pacing (,26.1% and ,32.1%, respectively) than during AV150 pacing (,8%, P = 0.02 and P = 0.07, respectively). This difference subsided 30 seconds after the onset of AVNRT or pacing. When upright, the mean BP time course was similar, but mean BP recovery during AVNRT was slower, and the difference between mean BP during AVNRT and AV150 persisted at 30 seconds. Conclusions: The initial mean BP decrease during AVNRT recovered gradually within 30 seconds. A short atrioventricular interval is associated with a greater mean BP decrease at the onset of tachycardia. These observations may explain clinical symptoms immediately after the onset of AVNRT. [source] Angiotensin-converting enzyme gene insertion/deletion polymorphism frequency in normotensive children with a positive family history of essential hypertensionJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 12 2009Lale Camci Aim: To evaluate the possible relationship between blood pressure (BP) and angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism in normotensive children with a positive family history of essential hypertension (EHT). Material and Methods: Three hundred seventy-six randomly selected normotensive schoolchildren (147 boys, 229 girls) between the ages of seven and 17 years were enrolled. Children were subdivided into a ,first-degree relative group' and a ,second-degree relative group' according to the presence of EHT in parents or grandparents, respectively. BP was measured twice from the right arm and the systolic BP, diastolic BP and mean BP were recorded. ACE gene I/D polymorphism was performed from all studied children and frequency od DD, ID and ID allele were analysed in each study group. Results: Allelic frequencies of the DD genotype of the ACE gene were higher in children with a positive history in the first- (36.2%) and second-degree (38.3%) relatives for EHT than the controls (30.7%) (P < 0.05 for both). Children with a positive family history of EHT and a DD genotype, had significantly higher SBP, DBP and MBP levels (P < 0.05) than the children with ID or II genotypes. Conclusion: We found that the ACE gene DD genotype was common and that BP levels were higher in Turkish children with a positive family history of EHT and DD genotype. Because the presence of DD allele might be the one of the potential contributor of EHT pathogenesis, further studies needed in large cohort for long term follow-up for EHT in children with DD allele. [source] Electroencephalographic arousals during sleep do not alter the pressor response to Cheyne,Stokes respiration in subjects with chronic heart failureJOURNAL OF SLEEP RESEARCH, Issue 4 2007GRANT N. WILLSON Summary This study examined the influence of electroencephalographic (EEG) arousal on the magnitude and morphology of the pressor response to Cheyne,Stokes respiration (CSR) in subjects with congestive heart failure (CHF). Thirteen subjects with stable CHF (left ventricular ejection fraction, 26 ± 7%) and CSR (apnea,hypopnea index 52 ± 15 h,1) underwent overnight polysomnography with beat-to-beat measurement of systemic arterial blood pressure (BP). CSR events were divided into those with or without an EEG arousal defined according to the criteria of the American Sleep Disorders Association. The pressor response was quantified in terms of the delta BP change (difference between the minimum BP during apnea and maximum BP during hyperpnea). Changes in the morphology of the pressor response were assessed by subdividing individual respiratory events into six periods (three during apnea: A1, A2, A3; and three during hyperpnea: H1, H2, H3). Considerable fluctuations in BP and heart rate (HR) were observed across the CSR cycle (delta mean BP 20.2 ± 6.5 mmHg). The presence of an EEG arousal did not alter the amplitude of fluctuations in BP. Mean blood pressure (MBP) increased 21.0 ± 7.5 mmHg with arousal versus 19.3 ± 5.8 mmHg without arousal (NS). A repeated measures ANOVA showed no significant interaction between the presence of arousal and the proportional change in mean BP across the six periods, indicating that an EEG arousal had no effect on the morphology of MBP change during CSR [F(5,60) = 1.44, P = 0.22]. This study showed that EEG-defined arousal does not amplify the pressor response to CSR in CHF. [source] Effects of Alcohol Withdrawal on 24 Hour Ambulatory Blood Pressure Among Alcohol-Dependent PatientsALCOHOLISM, Issue 12 2003Ramón Estruch Background: Although epidemiologic studies have reported an association between alcohol intake and high blood pressure (BP), the results of intervention studies have shown inconsistent results. We embarked on a study to determine whether different subgroups of alcohol-dependent patients may be identified in relation to the effect of alcohol on BP. Methods: Fifty alcohol-dependent men (mean age, 41.4 years) received 0.4 g of ethanol per kilogram of body weight every 4 hr in 200 ml of orange juice during 24 hr and the same amount of orange juice without ethanol during another 24 hr. Twenty-four hour ambulatory BP monitoring was performed during ethanol and orange juice intakes, as was hormonal and biochemical analysis. Results: Thirty-five (75%) alcohol-dependent men were normotensive and 15 (30%) hypertensive. Eighteen (51%) normotensive and 12 (80%) hypertensive subjects showed a significant decrease in 24 hr mean BP after ethanol withdrawal (mean decrease of 8.4 mm Hg [95% confidence interval, ,11.2 to ,5.7] and 12.5 mm Hg [confidence interval, ,16.2 to ,8.8], respectively) and were considered as sensitive to alcohol. The remaining alcohol-dependent subjects were considered as resistant to alcohol. Normotensive subjects sensitive to ethanol showed a significantly greater left ventricular mass and a significantly lower ejection fraction than those normotensive patients whose BP did not change after ethanol withdrawal (both p < 0.01). Conclusions: More than three fourths of the hypertensive and more than half of the normotensive alcohol-dependent patients showed sensitivity to the pressor effects of ethanol. Impairment also was observed in heart function in normotensive patients sensitive to the pressor effects of ethanol. [source] Altered Autonomic Cardiac Control Predicts Restenosis After Percutaneous Coronary InterventionPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2006MATTHIAS GOERNIG Background: Early and late restenosis in up to 30% remains a major problem for long-term success after percutaneous coronary intervention (PCI). Compared to bare metal stents, the use of drug-eluting stents reduces restenosis below 10%, but implant coasts have to be considered. In restenosis noninvasive testing lacks diagnostic power. We applied a new approach to identify patients with a high risk for restenosis after PCI by combining heart rate (HR) and blood pressure variability (BPV) analyses. Methods: In 52 patients with clinical suspicion of restenosis and history of PCI, we investigated patterns of cardiovagal autonomic regulation prior to cardiac catheterization. The patients were separated in (i) patients with restenosis (CAD+R) and (ii) patients without restenosis (CAD,R), where restenosis is defined as a stenosis greater than 75% of luminal diameter in at least one main vessel. The following parameters/methods were evaluated: Canadian Cardiovascular Society grade (CCS-grade), vessel disease score (CAD-level), left ventricular ejection fraction (LVEF), heart rate variability (HRV), BPV, baroreflex sensitivity (BRS), as well as HR turbulence and blood pressure (BP) potentiation caused by premature ventricular complexes. Results: Whereas age, LVEF, CAD-level, CCS-grade, and mean BP did not differ between CAD+R and CAD,R, significant differences were found in (i) BPV: diastolic LF/P, systolic, and diastolic UVLF, (ii) in BRS: slope of tachycardic sequences, and (iii) in extrasystolic parameters: heart rate turbulence onset (HRTO) and potentiation of systolic BP (SBPP). Standard HRV parameters did not show significant differences between the groups. Using the two parameters diastolic LF/P (threshold >0.2) and HRTO (threshold >0) restenosis were predicted in 83.4%. Conclusions: These results demonstrate that indicators of sympathetic activation or vagal depression identify restenosis in patients after PCI, thus opening a perspective for a new noninvasive monitoring. [source] Influence of exposure to electromagnetic field on the cardiovascular systemAUTONOMIC & AUTACOID PHARMACOLOGY, Issue 1 2005J. H. Jeong Summary 1 We examined whether extremely low frequency electromagnetic fields (ELF-EMF) affect the basal level of cardiovascular parameters and influence of drugs acting on the sympathetic nervous system. 2 Male rats were exposed to sham control and EMF (60 Hz, 20 G) for 1 (MF-1) or 5 days (MF-5). We evaluated the alterations of blood pressure (BP), pulse pressure (PP), heart rate (HR), and the PR interval, QRS interval and QT interval on the electrocardiogram and dysrhythmic ratio in basal level and dysrhythmia induced by , -adrenoceptor agonists. 3 In terms of the basal levels, there were no statistically significant differences among control, MF-1 and MF-5 in PR interval, QRS interval, mean BP, HR and PP. However, the QT interval, representing ventricular repolarization, was significantly reduced by MF-1 (P < 0.05). 4 (,)-Dobutamine (,1 -adrenoceptor-selective agonist)-induced tachycardia was significantly suppressed by ELF-EMF exposure in MF-1 for the increase in HR (,HR), the decrease in QRS interval (,QRS) and the decrease in QT (,QT) interval. Adrenaline (nonselective , -receptor agonist)-induced dysrhythmia was also significantly suppressed by ELF-EMF in MF-1 for the number of missing beats, the dysrhythmic ratio, and the increase in BP and PP. 5 These results indicated that 1-day exposure to ELF-EMF (60 Hz, 20 G) could suppress the increase in HR by affecting ventricular repolarization and may have a down-regulatory effect on responses of the cardiovascular system induced by sympathetic agonists. [source] Cardioprotective Effects of Angiotensin II Type 1 Receptor Blockade with Olmesartan on Reperfusion Injury in a Rat Myocardial Ischemia-Reperfusion ModelCARDIOVASCULAR THERAPEUTICS, Issue 1 2010Wangde Dai We determined the effects of olmesartan on infarct size and cardiac function in a rat ischemia/reperfusion model. Rats underwent 30 min of left coronary artery (CA) occlusion followed by 2 h of reperfusion. In protocol 1, the rats received (by i.v.) 1 mL of vehicle at 10 min after CA occlusion (Group 1, n = 15); olmesartan (0.3 mg/kg) at 10 min after CA occlusion (Group 2, n = 15); 1 mL of vehicle at 5 min before CA reperfusion (Group 3, n = 15); or olmesartan (0.3 mg/kg) 5 min before CA reperfusion (Group 4, n = 15). In protocol 2, the rats received (by i.v.) 1 mL of vehicle at 5 min before CA reperfusion (Group 5, n = 21); or olmesartan (3 mg/kg) at 5 min before CA reperfusion (Group 6, n = 21). Systemic hemodynamics, left ventricular (LV) function, LV ischemic risk zone, no-reflow zone, and infarct size were determined. In protocol 1, olmesartan (0.3 mg/kg) did not affect blood pressure (BP), heart rate, LV ± dp/dt or LV fractional shortening during the experimental procedure, and did not alter no-reflow or infarct size. In protocol 2, olmesartan (3 mg/kg) significantly reduced infarct size to 21.7 ± 4.1% from 34.3 ± 4.1% of risk zone in the vehicle group (P= 0.035), but did not alter the no-reflow size. Prior to CA reperfusion, olmesartan (3 mg/kg) significantly reduced mean BP by 22% and LV ±dp/dt, but did not affect heart rate. At 2 h after reperfusion, olmesartan significantly decreased heart rate by 21%, mean BP by 14%, and significantly increased LV fractional shortening from 54.1 ± 1.4% to 61.3 ± 1.6% (P= 0.0018). Olmesartan significantly reduced myocardial infarct size and improved LV contractility at a dose (3 mg/kg) with systemic vasodilating effects but not at a lower dose (0.3 mg/kg) without hemodynamic effects. [source] 2357: Autonomic nervous system and endothelial peripheral dysfunction in normal tension glaucoma patientsACTA OPHTHALMOLOGICA, Issue 2010J WIERZBOWSKA Purpose To define parameters of autonomic nervous system activity and peripheral vascular reactive hyperemia in normal tension glaucoma patients. Methods Ambulatory 24-hour electrocardiogram and blood pressure (BP) monitoring by using Lifecard CF and SpaceLab 90207-30 combined with occlusion provocation test were carried out in 54 NTG patients (44 women, mean age 59.7) and 43 matched control subjects (34 women, mean age 57.0). Heart rate variability (HRV) time and frequency domain parameters [low-frequency (LF), high-frequency (HR) and LF/HF ratio], and blood pressure variability (BPV) were calculated and analyzed for both study groups. Postocclusive hyperemia response parameters (TM - time to peak flow, TH ,half-time hyperaemia, TR ,time to rest flow, BZ-biological zero and MAX , maximum hyperemic response) were compared for patients with a nocturnal fall in mean BP (MPB) of less than 10% (non-dippers), of 10-20% (dippers) and of more than 20% (over-dippers) Results NTG patients demonstrated higher LF and LF/HF values for 24-hour period, day-time and night time than control subjects. There was no difference in BPV between study groups (10.4 ± 1.9 vs. 10.5 ± 2.1, p=0.790). In NTG patients, TH was significantly higher (79.0 ± 80.9 s vs. 51.5 ± 35.3 s, p=0.028) and BZ was significantly lower (2.3 ± 1.0 vs. 3.1 ± 2.0, p=0.009) as compared to the control group. There was statistically significant difference between NTG non-dippers, dippers and over,dippers in the BZ parameter (2.3 ± 0.9 vs. 2.7 ± 1.3 vs. 1.4 ± 0.4 p=0.024). Conclusion NTG patients exhibit abnormal ANS system activity and a different systemic hyperemia response as compared with healthy subjects. [source] Ambulatory blood pressure monitoring in patients with hyperthyroidism before and after control of thyroid functionCLINICAL ENDOCRINOLOGY, Issue 1 2005P. Iglesias Summary Background and Objective Thyroid hormones have pronounced effects on the cardiovascular system. Thyrotoxicosis affects blood pressure (BP), modifying both diastolic (DBP) and systolic (SBP) pressures. There are no studies examining BP with ambulatory blood pressure monitoring (ABPM) in hyperthyroidism before and after control of thyroid function. Our aims were (1) to analyse ABPM in a group of normotensive hyperthyroid patients before and after normalizing circulating thyroid hormones and (2) to compare these results with those obtained in a group of euthyroid subjects. Patients and Measurements We studied 20 normotensive hyperthyroid subjects [18 women; age (mean ± SEM) 49·0 ± 3·0 years] and 15 healthy subjects. Patients were evaluated by ABPM over 24 h, at diagnosis and after therapy (n = 18). Results The average 24-h, daytime and night-time SBP was significantly greater in hyperthyroid patients than in controls with no significant differences in DBP. Circadian BP rhythm, estimated by the difference between mean values of SBP, DBP and mean BP during daytime and night-time, was unchanged. The average 24-h and daytime SBP significantly decreased after normalizing thyroid function in the 18 hyperthyroid evaluated patients. Daytime SBP and DBP were higher than night-time values both before and after control of thyroid function. However, no differences in circadian BP rhythm were observed. Conclusions Normotensive hyperthyroid patients exhibit higher ambulatory SBP throughout 24 h than normotensive euthyroid subjects. Control of hyperthyroidism decreases ambulatory SBP values. Mean nocturnal fall in BP is comparable in normotensive hyperthyroid patients and control subjects. [source] | ||||||||||||||||||||||