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ABSTRACT: BACKGROUND: Continuous positive airway pressure (CPAP) treatment improves the risk of cardiovascular events in patients suffering from severe sleep apnea-hypopnea syndrome (SAHS) but its effect on the link between delta power band that is related to deep sleep and the relative cardiac vagal component of heart rate variability, HFnu of HRV, is unknown. Therefore, we tested the hypothesis that CPAP restores the link between cardiac autonomic activity and delta sleep across the night. METHODS: Eight patients suffering from severe SAHS before and after 4 +/- 3 years of nasal CPAP treatment were matched with fourteen healthy controls. Sleep EEG and ECG were analysed to obtain spectral sleep and HRV components. Coherence analysis was applied between HFnu and delta power bands across the first three sleep cycles. RESULTS: Sleep characteristics and spectral HRV components were similar between untreated patients, treated patients and controls, with the exception of decreased Rapid Eye Movement duration in untreated patients. Coherence and gain values between HFnu and delta EEG variability were decreased in untreated patients while gain values normalized in treated patients. In patients before and during long-term CPAP treatment, phase shift and delay between modifications in HFnu and delta EEG variability did not differ from controls but were not different from zero. In healthy men, changes in cardiac vagal activity appeared 9 +/- 7 minutes before modifications in delta sleep. CONCLUSIONS: Long-term nasal CPAP restored, in severe SAHS, the information between cardiovascular and sleep brainstem structures by increasing gain, but did not improve its tightness or time shift.
BMC Pulmonary Medicine 04/2013; 13(1):29. · 1.33 Impact Factor
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ABSTRACT: BACKGROUND:: Decreased endothelial NO bioavailability is one of the earliest events of endothelial dysfunction. Assessment of microvascular blood flow using a Laser Doppler Imager (LDI) during local, non-invasive administration of L-N-Arginine-Methyl-Ester (L-NAME) by skin iontophoresis may help discriminate the relative contributions of NO and non-NO pathways during a skin thermal hyperaemic test. METHODS:: In healthy non-smokers, the effects of thermal vasodilation and sodium nitroprusside (SNP)-mediated vasodilation were tested on skin pre-treated with 0.9% saline solution, 2% L-NAME iontophoresis (n=12), or intradermal injection of 25 nmol L-NAME (n=10). The effects of L-NAME iontophoresis were also measured in a group of smokers (n=10). RESULTS:: L-NAME iontophoresis and intradermal injection of L-NAME decreased the skin response to local heating to a similar degree (-41±4% vs -44±6%). L-NAME iontophoresis site-to-site and day-to-day coefficients of correlation were 0.83 and 0.76, respectively (p<0.01). The site-to-site and day-to-day coefficients of correlation of L-NAME injection were lower than those of iontophoresis at 0.66 (p<0.05) and 0.12, respectively (p=NS). SNP-induced skin hyperemia was not affected by L-NAME administration. L-NAME iontophoresis-mediated inhibition of skin thermal hyperaemia was greater in smokers than in non-smokers (p<0.05). CONCLUSION:: LDI assessment of skin thermal hyperaemia after L-NAME iontophoresis provides a reproducible and selective bedside method of qualitatively analyzing the contribution of the NO-pathway to microvascular vasomotor function.
Journal of cardiovascular pharmacology 01/2013; · 2.83 Impact Factor
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ABSTRACT: BACKGROUND:: Epidemiological and clinical studies have shown that traffic-related air pollution and, particularly, diesel exhaust particles (DEP) are strongly linked to cardiovascular mortality. METHODS:: Vascular toxicity was studied by assessing vasomotor responses of aortas isolated from normotensive Wistar rats exposed in vitro to DEP (DEP suspension and aqueous DEP extract). In vivo experiments were performed on Wistar rats and spontaneously hypertensive rats (SHR) exposed for 4 weeks via intratracheal instillation to either DEP or saline vehicle. After sacrifice, vascular responses to acetylcholine (ACh) or sodium nitroprusside (SNP) were assessed in vitro and the expression of p22phox, a major NADPH oxidase subunit, was studied by RTq-PCR. RESULTS:: In aortas from Wistar rats, in vitro DEP incubation (both preparations) markedly inhibited the relaxations to ACh and slightly to SNP; this effect was reversed in the presence of superoxide dismutase. In contrast, in aortas from in vivo-exposed animals, ACh-induced relaxations were only significantly impaired in the SHR group, accompanied with a significant up-regulation of p22phox, and no change in systolic blood pressure. CONCLUSIONS:: Although in vitro exposure to DEP produces a vascular oxidative stress, repeated in vivo exposures to DEP only impair vascular function in SHR, via an up-regulation of p22phox. This suggests a synergistic effect on endothelial dysfunction between particulate air pollution and hypertension.
Journal of cardiovascular pharmacology 09/2012; · 2.83 Impact Factor
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ABSTRACT: We aimed to assess whether arterial distensibility estimated by pulse wave velocity (PWV) and augmentation index (AI) differs between Cameroon traditional pygmies (TPs) on hunter-gather subsistence mode, contemporary pygmies who migrated to semiurban area, and the Bantou farmers (BFs) sharing the same environment. For that purpose, we recorded carotid-femoral PWV (ComplioR) in age and sex carefully matched 20 TPs, 20 contemporary pygmies, and 22 BFs. Aortic AI corrected for heart rate and blood pressures were generated from pressure wave analysis (SphygmoCor). Lipid profile was determined in TP and BF participants. TPs were shorter (P=0.02) with lower body weight (P<0.01) in comparison with contemporary pygmies and BFs. TPs had lower low-density lipoprotein cholesterol but higher high-density lipoprotein cholesterol than BFs (P<0.01). Their PWV (5.81±0.21 m/s) was slower (P=0.006) than that of contemporary pygmies (6.82±0.36 m/s) or BFs (6.93±0.29 m/s); however, after its adjustment for age, mean arterial pressure, and heart rate, the difference was slightly attenuated (P=0.051). PWV adjusted for weight did not differ between groups (P=0.10). In the whole study population but not in TPs taken separately, multivariate regression analysis revealed that PWV was independently associated with mean arterial pressure, age, and TP status (P<0.001), whereas age, mean arterial pressure, and height emerged as independent determinants of aortic AI corrected for heart rate (P<0.001). Aortic AI corrected for heart rate did not differ in the 3 groups. In conclusion, hunter-gather lifestyle is associated with low atherosclerosis risk translated by lower aortic stiffness attributed at least partly to low weight and blunted effects of aging and blood pressures on TP arterial structure and function.
Hypertension 05/2012; 60(1):123-8. · 6.21 Impact Factor
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ABSTRACT: Vitamin D deficiency (VDD) is associated with an increased cardiovascular risk. We investigated the effect of VDD on the cardiovascular system of growing male rats fed with a vitamin D-deficient diet. Using isolated rat aorta, we assessed both superoxide anion and endothelial-dependent relaxations. Microarray technology was used to identify changes induced by VDD in cardiac gene expression. Compared with control, VDD increased systolic blood pressure (P < 0.05) and superoxide anion production in the aortic wall (P < 0.05) and tended to increase serum levels of angiotensin II and atrial natriuretic peptide (P < 0.15). However, VDD slightly improved maximal relaxation to acetylcholine from 75 % ± 3% to 83% ± 2% (P < 0.05). Incubation of aortic rings either with nitro-l-arginine methyl ester (l-NAME) or catalase did not eliminate the enhancement of endothelial-mediated relaxation observed in vitamin D-deficient rats. Only incubation with indometacin or calcium-activated potassium channels blockers suppressed this difference. Compared with control, the expression of 51 genes showed different expression, including several genes involved in the regulation of oxidative stress and myocardial hypertrophy. In conclusion, VDD in early life increases arterial blood pressure, promotes vascular oxidative stress, and induces changes in cardiac gene expression. However, the endothelial-mediated regulation of vasomotor tone is maintained throughout the enhancement of an NO-independent compensatory pathway.
Journal of Cardiovascular Pharmacology 06/2011; 58(1):65-71. · 2.29 Impact Factor
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ABSTRACT: BELGICA-STROKE is a longitudinal study to enhance the use of online cardiovascular risk prediction scores based on the SCORE 10-year risk estimates for fatal cardiovascular disease (adapted for Belgium) and the Framingham 10-year stroke risk and to evaluate their impact on the cardiovascular risk profile of hypertensive patients. Methods and baseline characteristics are described here.
Prospective, multicenter study in primary care.
General practitioners (N = 810) recruited consecutive hypertensive patients aged >40 years who were not at blood pressure goal and assessed them every 4 months. The estimated 10-year risks for fatal cardiovascular disease and stroke were available on a secured, specially designed study website. The calculated risk profile of a patient was modifiable by adding treatment goals in order to increase awareness and motivation of both physician and patient. An automated feedback on goal-level attainment and both cardiovascular risk scores was provided.
Mean age of the 15,744 patients was 66.3 years: 51.9% were men, 77.8% had excess weight, 19.4% were smokers, and 25.9% had diabetes. Left ventricle hypertrophy was present in 20.0%, atrial fibrillation in 5.8%. Mean blood pressure was 153.8/88.2 mmHg, mean cholesterol 211.5 mg/dl. Most patients (89.2%) received antihypertensive medication, of which 36.9% was monotherapy. Mean estimated 10-year stroke risk was 19.1%, and mean estimated 10-year fatal cardiovascular disease risk 5.9%.
The 10-year estimated stroke and fatal cardiovascular disease risks were moderate to high in hypertensive patients not at goal blood pressure, emphasizing the importance of global cardiovascular risk factor assessment.
European journal of cardiovascular prevention and rehabilitation: official journal of the European Society of Cardiology, Working Groups on Epidemiology & Prevention and Cardiac Rehabilitation and Exercise Physiology 02/2011; 18(4):635-41. · 2.51 Impact Factor
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ABSTRACT: In physiological conditions, heart period (HP) affects systolic arterial pressure (SAP) through diastolic runoff and Starling's law, but, the reverse relation also holds as a result of the continuous action of baroreflex control. The prevailing mechanism sets the dominant temporal direction in the HP-SAP interactions (i.e., causality). We exploited cross-conditional entropy to assess HP-SAP causality. A traditional approach based on phases was applied for comparison. The ability of the approach to detect the lack of causal link from SAP to HP was assessed on 8 short-term (STHT) and 11 long-term heart transplant (LTHT) recipients (i.e., less than and more than 2 yr after transplantation, respectively). In addition, spontaneous HP and SAP variabilities were extracted from 17 healthy humans (ages 21-36 yr, median age 29 yr; 9 females) at rest and during graded head-up tilt. The tilt table inclinations ranged from 15 to 75° and were changed in steps of 15°. All subjects underwent recordings at every step in random order. The approach detected the lack of causal relation from SAP to HP in STHT recipients and the gradual restoration of the causal link from SAP to HP with time after transplantation in the LTHT recipients. The head-up tilt protocol induced the progressive shift from the prevalent causal direction from HP to SAP to the reverse causality (i.e., from SAP to HP) with tilt table inclination in healthy subjects. Transformation of phases into time shifts and comparison with baroreflex latency supported this conclusion. The proposed approach is highly efficient because it does not require the knowledge of baroreflex latency. The dependence of causality on tilt table inclination suggests that "spontaneous" baroreflex sensitivity estimated using noncausal methods (e.g., spectral and cross-spectral approaches) is more reliable at the highest tilt table inclinations.
AJP Regulatory Integrative and Comparative Physiology 10/2010; 300(2):R378-86. · 3.34 Impact Factor
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ABSTRACT: An abnormal circadian blood pressure (BP) profile is associated with adverse cardiovascular and all-cause outcomes. It is highly prevalent after heart, liver and kidney transplantation. We aimed to assess the prevalence of an abnormal ambulatory BP pattern in lung transplant recipients (LTx).
Ambulatory BP monitoring (ABPM) was performed in 53 LTx and compared to those of 42 control subjects matched for age, gender and daytime BP. In 19 patients in whom at least two recordings were performed, we compared the first and the last one.
The non-dipping pattern (a less than 10% reduction in nocturnal BP) was more prevalent in LTx than in control subjects (89 versus 64%, P < 0.01). Nighttime BP was higher in LTx than in control subjects (P < 0.01 and < 0.001 for systolic BP (SBP) and diastolic BP (DBP), respectively). The nocturnal reduction of BP was lower in LTx than in control subjects (3 versus 8% for SBP and 6 versus 13% for DBP, both P < 0.001). These results remained significant after adjustment for the presence of diabetes mellitus and creatinine clearance. In the 19 patients in whom ABPM was performed twice (mean interval between the two recordings was 22 months), ambulatory BP values remained unchanged between the two recordings, although the number of antihypertensive agents was significantly higher.
An abnormal circadian BP profile is highly prevalent after lung transplantation. It is observed consistently over prolonged periods of time.
Acta cardiologica 08/2010; 65(4):395-400. · 0.61 Impact Factor
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ABSTRACT: Resistance training has been introduced into rehabilitation to improve the efficiency of the 1980s traditional training. Among the modalities, the choice of recovery period length or repetition speed is hardly explained in term of functional benefit but not in terms of cardiovascular (CV) response. To our knowledge, no investigation has been made on the acute CV effect of repetition speed and rest periods between sets of such training during rehabilitation.
Our population included 17 male coronary patients. The experiment was performed on a leg extension device. A task force monitor noninvasive measurement system was used for continuous monitoring of the heart rate, systolic blood pressure and cardiac output. To evaluate the impact of the speed of contraction, individuals performed randomly, 3 x 10 repetitions (75% resistance maximum) at slow, moderate or fast pace. To evaluate the effect of the recovery period, individuals performed randomly, 3 x 10 repetitions separated by 30, 60, 90 or 120 s.
We observed a progressive drift of heart rate, systolic blood pressure and cardiac output between each rest period and sets for all the modalities. These drifts were more pronounced when the rhythm of contraction was slow or when the recovery period was short (30 or 60 s).
This work confirms the results of an earlier study showing that the main factor affecting the CV response is the length of the set. The 'ideal modality' should be three sets of 10 repetitions, at 75% resistance maximum, fast executed, with a 90 s recovery period between successive sets.
European journal of cardiovascular prevention and rehabilitation: official journal of the European Society of Cardiology, Working Groups on Epidemiology & Prevention and Cardiac Rehabilitation and Exercise Physiology 06/2010; 17(3):329-36. · 2.51 Impact Factor
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ABSTRACT: Arterial stiffness and wave reflection alterations may be implicated in the association between cardiovascular mortality, meteorological variables and ambient particulate matter air pollution. The present study explored the cross-sectional relations between ambient environmental parameters, arterial stiffness, peripheral and central hemodynamics in a large-scale cohort of hypertensive patients and normotensive controls.
The study comprised 1222 consecutive individuals who sought medical consultation in the hypertension outpatient clinics of the Hippokration' and 'Onassis' Hospitals (Athens, Greece) during a 3-year period (2004-2006). All individuals underwent a complete clinical and lipid-profile assessment at drug-free baseline. Carotid radial, carotid-femoral pulse wave velocity measurements and aortic pressure waveform analysis were performed noninvasively to all participants. Data from the National Technical University of Athens and the air quality department of the Hellenic Ministry for the Environment were used to estimate daily meteorological conditions and PM10 exposure.
In the total population, multiple-linear regression analysis revealed no significant associations between environmental variables and arterial stiffness. However, in men, the mean 5 day PM10 air concentration was independently associated with the augmentation pressure [2.0 mmHg (95% confidence interval (CI) 0.56-3.39) per 43.4 microg/m3] and the aortic-pulse pressure [2.78 mmHg (95% CI 3.91-5.12)] denoting a significant effect of particulate matter on the aortic-wave reflection magnitude and central hemodynamics. In addition, globally, the mean-daily temperature was related to the aortic-pulse pressure [-2.38 mmHg (95% CI -4.51 to -0.26) per 23.6 degrees C change] and the subendocardial viability ratio [5.85% (95% CI 1.1-10.6 per 23.6 degrees C)].
The exposure to lower environmental temperatures is related to impaired hemodynamics not only to the periphery but also to the aorta. In men, PM10 air-pollution levels are associated with heightened amplitude of the reflection wave leading to significant alterations in central-pulse pressure.
Journal of hypertension 05/2010; 28(5):903-9. · 4.02 Impact Factor
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ABSTRACT: Background: Arterial stiffness and wave reflection alterations may be implicated in the association between cardiovascular mortality, meteorological variables and ambient particulate matter air pollution. The present study explored the cross-sectional relations between ambient environmental parameters, arterial stiffness, peripheral and central hemodynamics in a large-scale cohort of hypertensive patients and normotensive controls.
Methods: The study comprised 1222 consecutive individuals who sought medical consultation in the hypertension outpatient clinics of the Hippokration' and ‘Onassis’ Hospitals (Athens, Greece) during a 3-year period (2004–2006). All individuals underwent a complete clinical and lipid-profile assessment at drug-free baseline. Carotid radial, carotid-femoral pulse wave velocity measurements and aortic pressure waveform analysis were performed noninvasively to all participants. Data from the National Technical University of Athens and the air quality department of the Hellenic Ministry for the Environment were used to estimate daily meteorological conditions and PM10 exposure.
Results: In the total population, multiple-linear regression analysis revealed no significant associations between environmental variables and arterial stiffness. However, in men, the mean 5 day PM10 air concentration was independently associated with the augmentation pressure [2.0 mmHg (95% confidence interval (CI) 0.56–3.39) per 43.4 μg/m3] and the aortic-pulse pressure [2.78 mmHg (95% CI 3.91–5.12)] denoting a significant effect of particulate matter on the aortic-wave reflection magnitude and central hemodynamics. In addition, globally, the mean-daily temperature was related to the aortic-pulse pressure [−2.38 mmHg (95% CI −4.51 to −0.26) per 23.6°C change] and the subendocardial viability ratio [5.85% (95% CI 1.1–10.6 per 23.6°C)].
Conclusion: The exposure to lower environmental temperatures is related to impaired hemodynamics not only to the periphery but also to the aorta. In men, PM10 air-pollution levels are associated with heightened amplitude of the reflection wave leading to significant alterations in central-pulse pressure.
Journal of Hypertension 04/2010; 28(5):903–909. · 4.02 Impact Factor
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ABSTRACT: The sympathetic nervous system has been reported to be activated in pulmonary arterial hypertension (PAH). Objectives: We investigated the prognostic significance of muscle sympathetic nervous system activity (MSNA) in PAH.
Thirty-two patients with PAH were included in the study and underwent a measurement of MSNA over a 6-year period of time. They had undergone a concomitant evaluation of New York Heart Association (NYHA) functional class, a 6-minute walk distance (6MWD), an echocardiographic examination, and a right heart catheterization for diagnostic or reevaluation purposes. The median follow-up time was 20.6 months (interquartile range, 45.8 mo). Clinical deterioration was defined by listing for transplantation or death.
Seventeen patients presented with clinical deterioration. As compared with the 15 others, they had an increased MSNA (80 +/- 12 vs. 52 +/- 18 bursts/min; P < 0.001) and heart rate (88 +/- 17 vs. 74 +/- 12 bpm; P = 0.01), a lower 6MWD (324 +/- 119 vs. 434 +/- 88 m; P < 0.01) and a deteriorated NYHA functional class (3.6 +/- 0.5 vs. 2.9 +/- 0.8; P < 0.001). The hemodynamic variables were not different. MSNA was directly related to heart rate and inversely to 6MWD. A univariate analysis revealed that increased MSNA and heart rate, NYHA class IV, lower 6MWD, and pericardial effusion were associated with subsequent clinical deterioration. A multivariate analysis showed that MSNA was an independent predictor of clinical deterioration. For every increase of 1 burst/minute, the risk of clinical deterioration during follow-up increased by 6%.
Sympathetic nervous system activation is an independent predictor of clinical deterioration in pulmonary arterial hypertension.
American Journal of Respiratory and Critical Care Medicine 03/2010; 181(11):1269-75. · 11.08 Impact Factor
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ABSTRACT: An information domain approach to the assessment of causality was applied to the beat-to-beat variability of heart period and systolic arterial pressure to test the open loop condition along baroreflex in heart transplant recipients. The closed loop between heart period and systolic arterial pressure was detected as open at the level of the baroreflex if systolic arterial pressure is more easily predictable from heart period than vice versa according to a conditional entropy approach. We found that in short-term heart transplant (STHT) recipients (less than 2 years after transplantation) the closed loop between heart period and systolic arterial pressure was open at the level of baroreflex. Baroreflex appeared to be involved in the heart period regulation in long-term heart transplant (LTHT) recipients (more than 2 years after transplantation). The significant linear correlation of causality index on the number of months after transplantation suggests that baroreflex control recovers after transplantation.
Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 01/2010; 2010:3449-52.
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ABSTRACT: BACKGROUND: Nebivolol is a highly selective beta-adrenoreceptor antagonist with vasodilating properties. This study investigated its effect on quality of life (QoL) and blood pressure (BP) in real life conditions. In total, 1468 patients were enrolled, 12% diabetics. Nebivolol was prescribed as monotherapy, add-on or switch medication. METHODS: In this open-label, prospective study, the JNC-VII BP target values were used: < 140/90 and < 130/80 mmHg for diabetics. The responder rate and the QoL was determined at baseline and after 4 and 8 weeks. RESULTS: After 4 weeks, 27% of subjects reached target BP, 45% after 8 weeks. The responder rates were 92, 90 and 83% for the monotherapy, add-on and switch groups. Compared with baseline, all showed statistical significance at 8 weeks. Similarly to results for the QoL after 8 weeks, the mean improvement in QoL for all three groups was 9-10 points (total range: 0-88). CONCLUSIONS: The study demonstrates that nebivolol in mild to moderate hypertension is associated with overall improvements in QoL, with a marked BP-lowering effect, in monotherapy, add-on or switch, irrespective of the glucose tolerance status. It may be hypothesized that its dual mode of action explains its BP-lowering effect as well as the tolerability.
Blood pressure. Supplement 10/2009; 1:5-14.
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ABSTRACT: Blockade of the skeletal muscle Na(+)-K(+)-ATPase pump by digoxin could result in a more marked hyperkaliema during a forearm exercise, which in turn could stimulate the mechano- and metaboreceptors. In a randomized, double-blinded, placebo-controlled, and cross-over-design study, we measured mean blood pressure (MBP), heart rate (HR), ventilation (V(E)), oxygen saturation (SpO(2)), muscle sympathetic nerve activity (MSNA), venous plasma potassium and lactic acid during dynamic handgrip exercises, and local circulatory arrest in 11 healthy subjects. Digoxin enhanced MBP during exercise but not during the post-handgrip ischemia and had no effect on HR, V(E), SpO(2), and MSNA. Venous plasma potassium and lactic acid were also not affected by digoxin-induced skeletal muscle Na(+)-K(+)-ATPase blockade. We conclude that digoxin increased MBP during dynamic exercise in healthy humans, independently of changes in potassium and lactic acid. A modest direct sensitization of the muscle mechanoreceptors is unlikely and other mechanisms, independent of muscle reflexes and related to the inotropic effects of digoxin, might be implicated.
Arbeitsphysiologie 09/2009; 107(5):581-6. · 2.15 Impact Factor
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Daniel Lemogoum,
Nassourou Hamadou,
Jean-Jacques Pik,
Joseph Dieuboue,
Sylvère Kaptue,
Jean Toto Moukouo,
William Ngatchou,
Marc Leeman,
Albert Nana,
Jean-Paul Degaute, Philippe Van de Borne
Journal of hypertension 08/2009; 27(7):1503-4. · 4.02 Impact Factor
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ABSTRACT: Background Arterial stiffening is more accelerated in blacks than in whites. Whether this is attributed to an enhanced vascular reactivity to environmental stress stimulation remains unknown. We therefore decided to test the hypothesis that cold pressor test (CPT) elicits a greater increase in arterial stiffness and an enhanced sympathetic skin vasoconstriction in African blacks than in whites normotensives.
American Journal of Hypertension 06/2009; 22(9):958-963. · 3.18 Impact Factor
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ABSTRACT: Arterial stiffening is more accelerated in blacks than in whites. Whether this is attributed to an enhanced vascular reactivity to environmental stress stimulation remains unknown. We therefore decided to test the hypothesis that cold pressor test (CPT) elicits a greater increase in arterial stiffness and an enhanced sympathetic skin vasoconstriction in African blacks than in whites normotensives.
A total of 17 young normotensive African blacks and 17 normotensive whites were recruited. All underwent continuous assessment of blood pressure (BP), heart rate, and carotid-femoral pulse wave velocity (PWVc-f) at rest, during and after hand immersion in iced water (CPT). Concomitantly, skin microvascular blood flow was monitored by laser Doppler flowmetry on the opposite hand.
At baseline, African blacks exhibited higher values of PWVc-f than whites (7.2 +/- 0.3 vs. 6.5 +/- 0.2 m/s, respectively, P = 0.04). During CPT the increases in systolic BP and PWVc-f were greater in African blacks than in whites (systolic BP 17 +/- 2 mm Hg vs. 9 +/- 3 mm Hg, P < 0.001 and PWVc-f 0.62 +/- 0.1 m/s vs. 0.26 +/- 0.1 m/s, P = 0.03, respectively). However, there was no significant difference in the PWVc-f responses among the groups during CPT after adjustment for the increments in mean BP. Finally, CPT induced a more pronounced skin microvascular vasoconstriction in African blacks than in whites (-54.4 +/- 5 % vs. -31.3 +/- 6 %, P < 0.001).
CPT provokes a more pronounced increase in PWVc-f in normotensive African blacks than in whites, that appears to be due to a greater increase in mean BP. Additionally, African blacks present an intensified skin microvascular response to the CPT as compared to their whites counterparts.
American Journal of Hypertension 06/2009; 22(9):958-63. · 3.18 Impact Factor
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ABSTRACT: 1. Recently, we have demonstrated that cigarette smoke exposure proportionally increases plasma nicotine levels and arterial wave reflection to the aorta. However, the exact contribution of nicotine to the smoke-induced enhancement of wave reflection and the potential underlying mechanisms have not been fully investigated. 2. The present study was a prospective study in 15 healthy male non-smokers. All received a placebo and a 2 mg nicotine tablet, according to a randomized double-blind cross-over study design. Each subject underwent repeated measurements at baseline and for 1 h after nicotine or placebo intake, using carotid-femoral pulse wave velocity (PWV) to assess arterial compliance. Concurrently, aortic pressures and the augmentation index were evaluated using applanation tonometry. 3. Plasma nicotine concentrations achieved 1 h after intake of the nicotine tablet reached comparable levels to those achieved after 1 h exposure to passive smoke (3.6 +/- 0.4 vs 3.2 +/- 0.4 ng/mL, respectively; P = 0.4). 4. Nicotine enhanced arterial wave reflection to the aorta, as assessed by the augmentation index corrected for heart rate (4.2 +/- 1.3 vs-0.7 +/- 0.8% with placebo; P = 0.001). In addition, a progressive increase in carotid-femoral PWV was noted after nicotine administration (0.3 +/- 0.1 vs-0.02 +/- 0.1 m/s with placebo; P = 0.04). This remained significant even after adjustment for changes in mean blood pressure and heart rate (P = 0.01). 5. Plasma nicotine concentrations comparable to those achieved after exposure to passive smoke enhance arterial wave reflection to the aorta. This is accompanied by an increase in carotid-femoral PWV, denoting a deterioration of arterial compliance by nicotine.
Clinical and Experimental Pharmacology and Physiology 02/2009; 36(8):784-9. · 1.85 Impact Factor
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ABSTRACT: To evaluate the prevalence of isolated uncontrolled systolic blood pressure (on-treatment isolated systolic hypertension) in treated hypertensive patients and identify the characteristics and treatment strategy in these patients.
Prospective cross-sectional survey in primary care. Participating physicians enrolled more than 13 consecutive treated hypertensive patients. Patients were considered to have isolated systolic hypertension when systolic blood pressure was at least 140 mmHg and diastolic blood pressure was less than 90 mmHg.
On-treatment isolated systolic hypertension occurred in 28% of evaluable patients (n = 11562) and in 36% of uncontrolled patients (n = 9080). Among the isolated systolic hypertension and among other uncontrolled patients, 53% and 47%, respectively, used more than one antihypertensive drug class. beta-Blockers were the most frequently prescribed antihypertensive drugs. Patients with isolated uncontrolled systolic blood pressure were more frequently treated with diuretics (43 vs. 39%) and angiotensin II receptor antagonists (23 vs. 17%). Despite blood pressure being under control in only 21% of the patients, hypertension treatment was not changed in 46% of patients with isolated uncontrolled systolic blood presssure vs. 14% of patients with both uncontrolled systolic and diastolic blood pressure.
In Belgium, the prevalence of on-treatment isolated systolic hypertension in treated hypertensive patients, was 28%. The goal blood pressure was likely not reached in most patients due to inadequate treatment. The overall control rate was worse for systolic than for diastolic blood pressure. Furthermore, antihypertensive treatment was less frequently adapted in patients with isolated uncontrolled systolic blood pressure than in those patients with both uncontrolled systolic and diastolic blood pressure.
Journal of Hypertension 11/2008; 26(10):2057-63. · 4.02 Impact Factor
