Association of left ventricular diastolic dysfunction with 24-h aortic ambulatory blood pressure: the SAFAR study

Aortic blood pressure (BP) and 24-h ambulatory BP are both better associated with target organ damage than office brachial BP. However, it remains unclear whether a combination of these two techniques would be the optimal methodology to evaluate patients' BP in terms of left ventricular diastolic dysfunction (LVDD) prevention. In 230 participants, office brachial and aortic BPs were measured by a validated BP monitor and a tonometry-based device, respectively. 24-h ambulatory brachial and aortic BPs were measured by a validated ambulatory BP monitor (Mobil-O-Graph, Germany). Systematic assessment of patients' LVDD was performed. After adjustment for age, gender, hypertension and antihypertensive treatment, septum and lateral E/Ea were significantly associated with office aortic systolic BP (SBP) and pulse pressure (PP) and 24-h brachial and aortic SBP and PP (P ⩽ 0.04), but not with office brachial BP (P ⩾ 0.09). Similarly, 1 standard deviation in SBP was significantly associated with 97.8 ± 20.9, 86.4 ± 22.9, 74.1 ± 23.3 and 51.3 ± 22.6 in septum E/Ea and 68.6 ± 2 0.1, 54.2 ± 21.9, 37.9 ± 22.4 and 23.1 ± 21.4 in lateral E/Ea, for office and 24-h aortic and brachial SBP, respectively. In qualitative analysis, except for office brachial BP, office aortic and 24-h brachial and aortic BPs were all significantly associated with LVDD (P ⩽ 0.03), with the highest odds ratio in 24-h aortic SBP. Furthermore, aortic BP, no matter in the office or 24-h ambulatory setting, showed the largest area under receiver operating characteristic curves (P ⩽ 0.02). In conclusion, 24-h aortic BP is superior to other BPs in the association with LVDD.

Statins: another class of antihypertensive agents?

The assessment of global cardiovascular risk is an essential step in the management of atherosclerotic disease prevention. Among the risk factors to be addressed are hypertension and hyperlipidaemia; these commonly coexist. A neutral or lipid-friendly antihypertensive agent is probably useful in the presence of lipid abnormalities. Similarly, statins have been shown to decrease cardiovascular risk in hypertensive patients. There is also experimental and clinical evidence that statins have blood pressure (BP)-lowering effects. In this review, we discuss the beneficial effects of statins on BP, and provide an overview of the underlying pathophysiology. We also consider the evidence justifying the use of statins in the management of hypertensive patients.

Plasma insulin, plasminogen activator inhibitor, and ankle-brachial systolic blood pressure ratio in overweight hypertensive subjects

BACKGROUND

In hypertensive subjects, the ratio between ankle and brachial systolic blood pressure (ABI) has been shown to be an independent risk factor for cardiovascular diseases, particularly in the elderly. Plasma insulin may be an important interconnecting factor explaining this observation.

PURPOSE

In a population of middle-aged subjects with essential hypertension and moderate overweight, we identified whether the decrease in the ABI ratio was associated with the clinical and biochemical factors involved in resistance to insulin. Patients with diabetes and/or arteriosclerosis obliterans of the lower limbs were excluded from the population. Subjects were or were not on antihypertensive therapy.

RESULT

On the basis of univariate correlations, the ABI ratio was found to be significantly and negatively associated not only with the degree of abdominal fat distribution, but also with the usual biological features of resistance to insulin: plasma triglycerides and cholesterol; plasma glucose and insulin; and plasminogen activator inhibitor (PAI) antigen. In a multivariate analysis in subjects with untreated hypertension, the ABI ratio was significantly and negatively associated with only three variables: age, plasma insulin and PAI antigen. In treated hypertensive subjects, only the role of age and insulin remained significant.

CONCLUSION

Since the alterations of the ABI ratio may be considered as a marker of the changes in the structure and function of arteries of the lower limbs, the study provides evidence that plasma insulin and PAI antigen, independently of the presence of significant atherosclerotic occlusive lesions, are susceptible to alter the pressure wave transmission in conduit arteries of the lower limbs.

Effect of antihypertensive treatment on lipids and fibrinogen: Greek multicentre study of cilazapril

The effect cilazapril (CLZ) treatment on serum lipids and fibrinogen was studied in 114 hypertensive patients for 18 weeks. Blood pressure, heart rate, lipid profile and fibrinogen were measured before and at the end of the study in all patients. Satisfactory blood pressure control was seen in 68% of the patients (group A) after 4 weeks of treatment with 5 mg CLZ monotherapy, while a single dose of chlorthalidone, 25 mg daily, was added to the therapeutic regimen of the remaining 32% of patients (group B) to achieve blood pressure control. We conclude that CLZ has a slight beneficial effect on the lipid profile and a significantly beneficial effect on fibrinogen, but its combination with a diuretic reverses this beneficial effect.

The efficacy of a transdermal formulation of clonidine in mild to moderate hypertension and its effects on the arterial and venous vasculature of the forearm

We have studied the efficacy of clonidine hydrochloride administered transdermally once a week for 9 to 15 weeks in 12 patients with mild to moderate hypertension. Clonidine reduced both supine and standing blood pressures on average, but only 8 subjects were responders, i.e. had a decrease in supine diastolic blood pressure to below 90 mm Hg or more than 10% from baseline. Supine heart rate was unchanged, but in the responders the orthostatic increase in heart rate was reduced by clonidine from baseline (p less than 0.05). Moreover, in all the patients the change in the orthostatic increase in heart rate was correlated with the change in supine diastolic pressure (p less than 0.05). Brachial artery blood flow, forearm arterial compliance, vascular resistance, and venous tone were not affected by clonidine. Thus, transdermal clonidine reduced blood pressure, probably by a baroreflex-mediated effect, but did not affect the vasculature of the forearm.

Pulse wave velocity in patients with obesity and hypertension

Pulse wave velocity was measured in 27 obese and 25 nonobese patients with sustained essential hypertension. Pulse wave velocity was significantly increased in obese patients in comparison with nonobese patients. The result was independent of age, sex, and level of blood pressure. In the overall population, a significant positive correlation (r = 0.85; p less than 0.001) was observed between the degree of obesity and pulse wave velocity. A study of partial correlation coefficients indicated that the levels of glycemia, cholesterolemia, and triglyceridemia did not influence the relationship. After body weight was reduced, blood pressure decreased and arterial compliance increased. The results show that in patients with sustained essential hypertension: pulse wave velocity and obesity are strongly related independent of age, sex, blood pressure, and associated metabolic disorders and body weight reduction is associated with an improvement of arterial distensibility and compliance.

Extracellular and interstitial fluid volume in obesity with and without associated systemic hypertension

Fluid volumes and cardiac and renal hemodynamics were investigated in 44 obese men, 22 with normal blood pressure and 22 with sustained essential hypertension. For the same degree of obesity hypertensive patients had a higher value in extracellular (p less than 0.05) and interstitial fluid (p less than 0.01) volumes than normotensive subjects, while plasma volume, total body water, body cellular water, cardiac output, renal blood flow and glomerular filtration rate were similar. For the same level of blood pressure, the expansion of extracellular and interstitial fluid volume paralleled the degree of obesity. Thus, obese patients with hypertension have an absolute increase in extracellular and interstitial fluid volumes. The increase was related both to the degree of overweight and to the mechanisms of hypertension.

Comparison of oral MK 421 and propranolol in mild to moderate essential hypertension and their effects on arterial and venous vessels of the forearm

The efficacy of MK 421 and propranolol was compared in 48 patients with mild to moderate hypertension. Each patient was randomly assigned to receive 1 of the drugs for 12 weeks. Additionally, a subgroup of 28 patients underwent studies of forearm arterial and venous circulation by means of pulsed Doppler and mercury-in-silastic plethysmography. Both drugs reduced supine and standing blood pressure (BP) (p less than 0.001). Propranolol reduced heart rate (p less than 0.001), while MK 421 did not change it. Brachial artery diameter, blood velocity and flow increased after MK 421 (p less than 0.001), but were not changed after propranolol therapy. Forearm vascular resistance decreased after MK 421 (p less than 0.001) and after propranolol (p less than 0.05). Forearm venous tone was unaffected on MK 421, but increased after propranolol (p less than 0.01). Thus, in moderate hypertension, 3 months of treatment with MK 421 or propranolol similarly decrease BP, but affect the forearm circulation differently: MK 421 dilates both the brachial artery and the arterioles of the forearm, but does not affect the venous vessels, and propranolol causes little arterial change but increases the forearm venous tone.

Adipose tissue cellularity and hemodynamic indexes in obese patients with hypertension

Fat-cell weight, fat-cell number, and hemodynamic indexes were determined in 25 obese men with sustained elevation of BP. Fat-cell weight (and not fat-cell number) was positively correlated with overweight (r = .51) and mean arterial pressure (MAP) (r = .57) in basal conditions. After body weight reduction, BP decreased significantly through a decrease in cardiac index due to a predominant decrease in heart rate. Simultaneously, fat-cell weight decreased significantly. The ratio between the change in BP and the change in body weight, ie, the ability to decrease pressure per unit weight loss, was positively related to the level of initial BP (r = .80) and reached a plateau above 120 mm Hg of the initial MAP. We suggest that, in patients with obesity and hypertension, high BP is associated with hypertrophic obesity, and after body weight reduction, the simultaneous decrease in BP, heart rate, and fat-cell weight could be mediated by neurogenic mechanisms.

[Systolic arterial hypertension in patients amputated for injury]

The blood pressure of 106 men who had undergone amputation of one limb on account of war injury was compared with that of 184 male controls of the same ages. All subjects with a diastolic pressure above 90 mmHg were excluded from the study. The diastolic pressure was statistically equivalent in both groups, but the amputees had a significantly higher systolic pressure. Changes in the visco-elastic properties of the arterial system related to amputation might be responsible for this rise in systolic pressure.

Intravascular volume, extracellular fluid volume, and total body water in obese and nonobese hypertensive patients

Intraarterial blood pressure, plasma volume, extracellular and interstitial (IFV) fluid volumes, and total and intracellular (IBV) body water were evaluated in 50 men: 16 obese hypertensive patients, 16 nonobese hypertensive patients, and 18 normal subjects of similar age. In obese hypertensive subjects, the IBW/IFV ratio was significantly increased (p less than 0.01) in comparison with both control subjects and nonobese hypertensive patients. After body weight reduction, blood pressure (p less than 0.01), heart rate (p less than 0.05), and the IBW/IFV ratio (p less than 0.01) significantly decreased. The decrease in the ratio was due to an absolute increase in the interstitial fluid volume, related to a shift of fluid volume from the intracellular to the interstitial space. Thus, obese hypertensive patients have an increased water cell content, causing an altered partition between the intracellular and the interstitial spaces.

[Comparative hemodynamic effects of 2 vasodilators: dihydralazine and diltiazem in permanent essential arterial hypertension]

Cardiac hemodynamic and diameter, blood flow velocity, volumic flow of the brachial artery measured by pulsed Doppler, were studied before and after diltiazem administration in comparison with dihydralazine in hypertensive patients. After diltiazem administration, blood pressure and total peripheral resistance significantly decreased (P less than 0.001) while cardiac index and heart rate increased (P less than 0.01). After 25 minutes perfusion cardiac output and heart rate returned toward control values, while blood pressure and total peripheral resistance remained decreased. The result contrasted with those observed after dihydralazine, which induced an increase in cardiac index and heart rate. The caliber of the brachial artery decreased significantly (P less than 0.001) after dihydralazine and increased after diltiazem (P less than 0.01). This study shows that 1). The antihypertensive effect of diltiazem was due to a fall in total peripheral resistance associated with a transient baroreflex mediated tachycardia, and 2) diltiazem dilated also large arteries.