Atenolol Group Research Articles

Angiotensin Receptor Blocker Added to Previous Antihypertensive Agents on Arteries of Diabetic Hypertensive Patients

Lowering elevated blood pressure (BP) in diabetic hypertensive individuals decreases cardiovascular events. We questioned whether remodeling of resistance arteries from hypertensive diabetic patients would improve after 1 year of tight BP control with addition of either the angiotensin receptor blocker (ARB) valsartan or the beta-blocker (BB) atenolol to previous therapy, which included angiotensin-converting enzyme inhibitors (ACEIs) and/or calcium channel blockers. Twenty-eight hypertensive type 2 diabetic patients treated with oral hypoglycemic and antihypertensive agents (not receiving ARBs or BBs) were randomly assigned to double-blind treatment for 1 year with valsartan (80 to 160 mg) or atenolol (50 to 100 mg) daily, added to previous therapy. Resistance arteries dissected from gluteal subcutaneous tissues were assessed on a pressurized myograph. After 1 year of treatment, systolic and diastolic BP and glycemia were equally well controlled in the valsartan and atenolol groups. Endothelium-dependent and independent relaxation did not change in the treated groups. After 1 year of treatment, resistance artery media:lumen ratio decreased in the valsartan group (7.9+/-0.5% after versus 9.8+/-0.6% before; P < 0.05) but not in the atenolol-treated group (9.9+/-0.9% versus 10.6+/-1%; P value not significant). Artery walls from atenolol-treated patients became stiffer, with no change in the valsartan-treated patients. In conclusion, similar intensive BP control for 1 year with valsartan was associated with improved structure of resistance arteries in diabetic hypertensive patients, whereas vessels from atenolol-treated patients exhibited unchanged remodeling and a stiffer wall. The addition of ARBs but not BBs to antihypertensive medications that may include angiotensin-converting enzyme inhibitors and/or calcium channel blockers results in an improvement in resistance artery remodeling in diabetic hypertensive patients.

Lessons learned from a randomised controlled study of perioperative beta blockade in high risk patients undergoing emergency surgery

Perioperative beta blockade has been shown to reduce mortality after major elective surgery. The aim of this study was to determine whether it could reduce the rate of death and morbidity from cardiac complications in high risk patients undergoing emergency surgery. Over a one-year interval all patients undergoing major non-elective orthopaedic or general surgery were screened to identify those at high risk of cardiac complications. Consenting, high risk patients were randomly allocated atenolol or placebo for seven days, commencing at anaesthetic induction. Deaths and cardiac complications within 30 days were recorded. Some 2351 patients had an emergency operation; 145 were at high risk and eligible for the study. Of 89 patients approached, 57 initially consented. Only 38 patients, however, completed the study protocol, 19 were withdrawn. Of those who completed the study, 5/20 patients in the placebo group and 3/18 in the treatment group died before hospital discharge (p=0.520). Four others in the placebo group and two in the atenolol group had post-operative non-fatal cardiac events (positive troponin T), p=0.311. This study of emergency surgery proved more difficult than similar trials in elective surgery. The final study groups were small and there were no significant differences in outcomes. A much larger study is required for a definitive answer.

Depressive Symptoms in Coronary Artery Disease Patients After Hypertension Treatment

Depression is highly prevalent and frequently recurs in patients with coronary artery disease (CAD) and hypertension. Certain medications used to treat hypertension are alleged to be associated with higher risk of depression. To compare depressive symptoms before and during treatment with 2 equivalent hypertension treatment strategies in patients with CAD stratified according to a self-reported history of physician-diagnosed depression. Patients enrolled in a randomized hypertension treatment study were mailed baseline and one year follow-up surveys and stratified according to a self-reported history of depression. Patients (N = 1152) were 50 years old or older with hypertension and clinically stable CAD. Depressive symptoms were measured using the Center for Epidemiologic Studies-Depression (CES-D). High risk of depression was defined as a history of physician-diagnosed depression reported by patients on the baseline survey. Depressive symptoms were compared for verapamil sustained-release (SR)- and atenolol-based hypertension treatment. Among patients with a previous history of depression, depressive symptoms improved over the one year follow-up period for patients assigned to both treatment regimens. Depressive symptoms improved for patients with no depression history in the verapamil SR group (p < 0.001) and were unchanged in the atenolol group (p = 0.52). Patients assigned to the atenolol-based strategy without prior history of depression were more likely to worsen 5 or more points on the CES-D. When antihypertensive treatment options are clinically equivalent, prescribers may first consider using a verapamil SR-based strategy, especially in patients with CAD who have no history of depression.

How can we block sympathetic overactivity? Effects of rilmenidine and atenolol in overweight hypertensive patients

The aim of the present study was to evaluate effects of long-term treatment with rilmenidine compared with atenolol on lipid and glucose metabolism and cardiovascular remodelling in hypertension. In total, 37 patients with hypertension were randomised to rilmenidine 1-2 mg/day or atenolol 50-100 mg/day for 26 weeks. Standard oral glucose tolerance test with a parallel measurement of insulin and glucose levels was performed. The 'areas under the curve' (AUC) for insulin and glucose were calculated. Plasma lipids, left ventricular mass index (LVMI), and intima-media thickness (IMT) were measured. Brachial artery diameter during reactive hyperaemia was used to test endothelium-dependent vasodilatation (EDVD). Blood pressure reduction was equally achieved in both treatment arms. The fasting glucose level increased in the atenolol group from 4.8+/-0.6 to 5.2+/-0.7 mmol/l (P<0.01). The AUC of glucose in rilmenidine group decreased from 860+/-93 to 737+/-66 mmol/min/l (P<0.05), and in the atenolol group it increased from 937+/-86 to 989+/-88 mmol/min/l (P<0.05). Rilmenidine showed a positive effect on lipid levels, whereas in the atenolol group a significant decrease of high-density lipoprotein cholesterol was observed. Left ventricular mass index decreased with rilmenidine by 9.6% and by 6.9% with atenolol (P<0.05). Intima-media thickness significantly decreased in the rilmenidine group. Endothelium-dependent vasodilatation slightly increased on in the rilmenidine group, while on in the atenolol group it remained unchanged. Our data suggest that in hypertensive patients central inhibition of sympathetic drive can produce favourable effects on glucose and lipid metabolism compared with standard beta-blockade with a similar antihypertensive efficacy. Rilmenidine also provides beneficial effects on cardiovascular remodelling and altered endothelial function in hypertension.

Long‐Term Effects of a Losartan‐Compared With an Atenolol‐Based Treatment Regimen on Carotid Artery Plaque Development in Hypertensive Patients With Left Ventricular Hypertrophy: ICARUS, a LIFE Substudy

In the Losartan Intervention for Endpoint Reduction in Hypertension (LIFE) study, there was a 25% risk reduction for stroke with angiotensin receptor blocker-based therapy (losartan) as compared with beta-blocker-based therapy (atenolol) despite comparable blood pressure reductions. This substudy examines treatment effects on the amount and density of atherosclerotic lesions in the common carotid arteries and the carotid bulb in 81 patients during 3 years of treatment. There were no statistically significant changes in the amount of carotid plaque in patients treated with losartan compared with an atenolol-based treatment program. A statistically nonsignificant increase in plaque density and index (average of plaque amount and density) was seen in the atenolol group compared with those treated with losartan. The small number of patients evaluated may have limited the power to detect a difference in outcome. The difference in carotid plaque index increase between the treatment groups during 3 years of treatment could not be statistically linked to specific treatments in the present substudy.

Effects of Atenolol and Losartan on Baroreflex Sensitivity and Heart Rate Variability in Uncomplicated Essential Hypertension

Baroreflex sensitivity (BRS) and heart rate variability (HRV) are potential therapeutic targets. The present study was conducted to assess changes in BRS and HRV after monotherapy with losartan versus that of atenolol in uncomplicated essential hypertension. Thirty subjects with uncomplicated essential hypertension were randomized to receive atenolol 50 mg to 100 mg (n = 15) or losartan 50 mg to 100 mg (N = 15) daily for 6 months. Instantaneous systolic blood pressure (SBP) and heart rate were assessed using servo-controlled infrared finger plethysmography before treatment and at the end of 3 months and 6 months after treatment. The fluctuation in SBP and interpulse interval (IPI) was divided into three specific frequency ranges by fast Fourier transform as high frequency (HF; 0.15 Hz-0.4 Hz), low frequency (LF; 0.04 Hz-0.15 Hz), and very low frequency (VLF; 0.004 Hz-0.04 Hz). The BRS was expressed as (1) SBP-IPI transfer function with its magnitude in the HF and LF ranges and (2) BRS index alpha. The HRV was expressed as total power and power in the LF and HF ranges of interpulse interval. Blood pressure was reduced to a similar extent in both groups. Compared with the baseline, BRS did not improve in both groups at month 3. However, BRS was significantly improved in the losartan group (P < 0.05) but not in the atenolol group at month 6. In addition, BRS was significantly higher in the losartan group than the atenolol group at month 3 and month 6 (P < 0.05). Moreover, heart rate variability was significantly reduced in the atenolol group at month 6 (P < 0.05), but not in the losartan group. The HRV in the losartan group was significantly higher than that in the atenolol group at month 6 (P < 0.05). These findings suggest superior effects of losartan on BRS and HRV than atenolol in uncomplicated essential hypertension, which may be beyond blood pressure reduction/resetting.

THE WAYS OF SYMPATHETIC SYSTEM OVERACTIVITY BLOCKING: RILMENIDINE VERSUS ATENOLOL

Aim. To evaluate effects of long-term treatment with rilmenidine compared with atenolol on lipid and glucose metabolism and cardiovascular remodeling in hypertension. Material and methods. 37 patients with hypertension were randomized to rilmenidine 1-2 mg/day or atenolol 50-100 mg/day for 26 weeks. Standard oral glucose tolerance test with a parallel measurement of insulin and glucose levels was performed. The “areas under the curve” (AUC) for insulin and glucose were calculated. Plasma lipids, left ventricular mass index (LVMI) and intima-media thickness (IMT) were measured. Brachial artery diameter during reactive hyperemia was used to test endothelium-dependent vasodilatation (EDVD). Results. Blood pressure reduction was equally achieved in both treatment arms. The fasting glucose level increased in the atenolol group from 4.8±0.6 to 5.2±0.7 mmol/l (p&lt;0.01). The AUC of glucose in rilmenidine group decreased from 860±93 to 737±66 mmol/min/l (p&lt;0.05), and it increased from 937±86 to 989±88 mmol/min/l (p&lt;0.05) in the atenolol group. Rilmenidine showed a positive effect on lipid levels, while in the atenolol group a significant decrease of high density lipoprotein was observed. LVMI decreased with rilmenidine by 9.6% (p&lt;0.05) and by 6,9% (not significantly) with atenolol. IMT significantly decreased in the rilmenidine. EDVD slightly increased on rilmenidine, while on atenolol group it remained unchanged. Conclusion. Our data suggest that in hypertensive patients central inhibition of sympathetic drive can produce favorable effects on glucose and lipid metabolism compared with standard β-blockade with a similar antihypertensive efficacy. Rilmenidine also provides beneficial effects on cardiovascular remodeling and altered endothelial function in hypertension.

Exercise performance during losartan‐ or atenolol‐based treatment in hypertensive patients with electrocardiographic left ventricular hypertrophy (a LIFE substudy)

The objective of the study was to assess the influence of left ventricular (LV) hypertrophy regression on exercise capacity in hypertensive patients. Doppler echocardiography was performed at rest and during exercise in 51 patients with electrocardiographic LV hypertrophy before and after 1 year of randomized blinded losartan‐ or atenolol‐based antihypertensive treatment. After 1 year, blood pressure was comparably reduced by 32/14 and 27/13 mmHg, respectively, in the losartan and atenolol groups, but the atenolol group had higher mean LV mass index (118 vs 103 g/m2) and lower LV ejection fraction (61% vs 67%) and midwall shortening (15.8% vs 16.8%) (all p<0.05). Resting diastolic Doppler indices remained unchanged and did not differ between the groups. Peak oxygen uptake during exercise was virtually unchanged after 1 year and did not differ between the groups in spite of a lower peak exercise heart rate in atenolol‐treated patients. In multivariate analysis, higher peak oxygen uptake at 1 year was associated with lower body mass index, and higher systolic blood pressure and shorter isovolumic relaxation time at peak exercise (multiple R2 = 0.51, p<0.01), while age, gender, heart rate increase during exercise, reduction in LV mass and study treatment did not enter. In conclusion, reduction in blood pressure and LV mass induced by losartan or atenolol treatment was not accompanied by improved exercise capacity after 1 year. The results may be explained by persistent impairment of myocardial relaxation influencing exercise capacity.

The Effect of Carvedilol on Metabolic Parameters in Patients With Metabolic Syndrome

The objective of the present study was to explore the effect of carvedilol treatment on metabolic parameters in patients with metabolic syndrome. A total of 77 patients > or = 20 years of age (59 females, 18 males, mean age, 52.3 +/- 10.3) with stage 1 hypertension who fulfilled at least 3 of the metabolic syndrome criteria proposed by NCEP-ATP III were included in this prospective, randomized, controlled study. Patients were randomly assigned to receive daily treatment with carvedilol (n = 27, 12.5 mg/day orally for the first 2 days and 25 mg/day thereafter), atenolol (n = 26, 50 mg/day orally), or doxazosin (n = 24, 2 mg/day orally) for 90 days. Doses were doubled at the end of the 3rd week in patients whose blood pressure was inadequately controlled and amlodipine 10 mg was added to the treatment if the target blood pressure was still not reached at the end of week 6. The biochemical parameters and insulin sensitivity based on the HOMA-IR model were evaluated at baseline and at the end of treatment. Similar reductions in systolic and diastolic blood pressure were observed in all groups (P > 0.05). A significant decrease in HDL cholesterol levels occurred in the doxazosin and atenolol groups compared to the carvedilol group (percent change: -5.6 +/- 13.5 and -8 +/- 9.8 versus -0.1 +/- 12.2, respectively; P < 0.05) and a significant increase in apolipoprotein A1 level was observed in the carvedilol group compared to the doxazosin and atenolol groups (percent change: + 4.3 +/- 9.6 versus - 0.5 +/- 10.6 and -2.3 +/- 6.6, respectively; P < 0.05). There were no significant differences among the groups with respect to other parameters. It is concluded antihypertensive treatment with carvedilol in patients with metabolic syndrome effectively reduces blood pressure without adversely affecting metabolic parameters.

Effect of Nebivolol and Atenolol on Brachial Artery Flow-Mediated Vasodilation in Patients with Coronary Artery Disease

Endothelial dysfunction is considered to be the first step in atherogenesis as well as a predictor of adverse cardiovascular events in patients with coronary artery disease (CAD), while endothelial function improvement is associated with improved clinical outcome. Nebivolol is a beta1-adrenoreceptor antagonist with an independent beneficial action on endothelial function, increasing nitric oxide bioavailability. The aim of the present study was to examine the effects of nebivolol on endothelial function in the brachial artery in patients with CAD compared with another selective beta1 adrenergic receptor antagonist, atenolol. Thirty-five patients with stable CAD were randomized to receive either 5 mg nebivolol (n = 17) or 50 mg atenolol (n = 18) daily for 4 weeks. Each patient underwent measurement of endothelial function by means of flow-mediated dilatation (FMD) of the brachial artery before and after 4 weeks of treatment. All vasoactive drugs and cardiovascular risk factors were comparable in the two groups. No significant differences were observed between the two groups at baseline in FMD. In the atenolol group FMD remained unchanged at the end of the 4-week treatment, but in patients treated with nebivolol FMD showed a significant increase by the end of the treatment period (3.9 +/- 2.7% vs. 5.6 +/- 2.9%, p = 0.047) leading to a significantly higher value compared to patients treated with atenolol (5.6 +/- 2.9% vs. 3.4 +/- 3.2%, p = 0.041).Beta(1) blockade by nebivolol but not atenolol improves endothelial dysfunction in patients with CAD, an effect that might further reduce the risk for cardiovascular events in patients with CAD.

C-Reactive Protein Elevation Predicts Pulse Pressure Reduction in Hypertensive Subjects

Cross-sectional studies have shown a positive association between increased pulse pressure (PP) and an increased likelihood of a C-reactive protein (CRP) level >3 mg/L. In a retrospective subgroup analysis of the hypertensive subjects of the multicenter double-blind study, REASON (PREterax in Regression of Arterial Stiffness in a ContrOlled Double-BliNd), in which fixed first-line antihypertensive combination therapy with an angiotensin converting enzyme (ACE) inhibitor, perindopril (2 mg), and a diuretic, indapamide (0.625 mg), proved significantly more effective than atenolol in normalizing PP, we sought to determine whether perindopril plus indapamide was also more effective than atenolol in lowering CRP levels and, if so, whether this effect correlated with a preferential reduction in PP. At the final visit (12 months) in the 269 patients studied, the decrease in PP was greater, and the proportion of patients with CRP >3 mg/L lower (17.9% versus 28. 9%, P=0.03; adjusted odds ratio, 1.02 to 4.08, P=0.01), in the perindopril plus indapamide group than in the atenolol group. After adjustment for confounders, patients with a baseline CRP >3 mg/L displaying the greatest decrease in PP were more likely (P=0.04) to have a CRP < or =3 mg/L at 12 months. No such relationship was found with systolic or diastolic blood pressure. Perindopril-indapamide combination therapy is more effective than beta-blockade in lowering elevated CRP in hypertensive subjects. This effect is significantly associated with a more effective PP reduction in patients with baseline CRP >3 mg/L.

A Comparison of the Two β-Blockers Carvedilol and Atenolol on Left Ventricular Ejection Fraction and Clinical Endpoints after Myocardial Infarction

Background: β-Blockers have been found to reduce mortality and morbidity in postmyocardial infarction patients. However, it is not fully understood whether all β-blockers have similar favourable cardiovascular effects. The aim of this study was to compare the effects of carvedilol and atenolol on global and regional left ventricular ejection fraction (LVEF) and on predefined cardiovascular endpoints. Methods: In a single-centre, randomized, open, endpoint-blinded, parallel group study, 232 patients with acute myocardial infarction were randomized to treatment with carvedilol or atenolol. LVEF was measured by gated blood pool scintigraphy during the first week and after 12 months. The treatment was given orally within 24 h. The mean dose was 36.2 and 72.1 mg in the carvedilol and atenolol groups, respectively. Results: No significant difference was found between the two study groups in the mean global and regional LVEF. There tended to be fewer first serious cardiovascular events in the carvedilol compared with the atenolol group (RR = 0.83, 95% CI 0.56–1.23, p = 0.39). Cold hands and feet were observed less frequently in the carvedilol group (20 vs. 33%, p = 0.025). Conclusion: In patients following an acute myocardial infarction, no difference in either global or regional LVEF was observed between baseline and 12 months when treatment with carvedilol was compared with atenolol.

Effect of Manidipine as Compared to Atenolol on Platelet Aggregation in Elderly Patients with Isolated Systolic Hypertension and Type II Diabetes Mellitus

This study was done to evaluate the effect of treatment with manidipine as compared with atenolol on thrombin-mediated platelet aggregation in elderly patients with isolated systolic hypertension and type II diabetes mellitus. After a 2-week washout placebo period, 60 elderly patients (aged 65-80 years) with isolated systolic hypertension (SBP > 140 mm Hg and DBP < 90 mm Hg) were randomly assigned to manidipine 10 mg or atenolol 50 mg 6-week treatment according to a double-blind, crossover design. Thirty patients had a concomitant well-controlled type 2 diabetes mellitus (HbA1c < or = 6.5%). At the end of the washout and of each treatment period, blood pressure (BP) (by mercury sphygmomanometer) and platelet aggregation (by Born-type aggregometer) were evaluated. Blood samples were collected using sodium citrate as anticoagulant, and platelet aggregation was induced by 2 different concentrations of ADP and collagen. Manidipine and atenolol produced a significant BP reduction in both diabetic and nondiabetic patients, with no difference between treatments. Despite the similar BP effect, in diabetic patients manidipine produced a significant reduction in platelet aggregation induced by both doses of either ADP or collagen. In nondiabetic hypertensives, manidipine inhibited platelet aggregation only at the highest doses of both inducers. The difference in the platelet inhibitory effect of manidipine between diabetic and nondiabetic subjects was statistically significant (P < 0.05) at both inducer concentrations. No changes in platelet aggregation were observed in the atenolol group. These data indicate that, unlike atenolol, manidipine inhibits platelet aggregation in elderly hypertensive patients, expecially in those with associated type II diabetes mellitus. The clinical impact of this positive effect in terms of prevention of cardiovascular complications in these high-risk patients remains to be clarified.

Pulse Pressure and Effects of Losartan or Atenolol in Patients With Hypertension and Left Ventricular Hypertrophy

In the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study, the primary composite end point of cardiovascular death, stroke, and myocardial infarction was reduced by losartan versus atenolol in patients with hypertension and left ventricular hypertrophy. The objective of this post hoc analysis was to determine the influence of pulse pressure on outcome. Patients were divided into quartiles of baseline pulse pressure. Cox regression, including baseline Framingham risk score as a covariate, was used to compare risk in the quartiles. In the atenolol group, there were significantly higher risks in the highest versus lowest quartile for the composite end point 28% (confidence interval [CI], 2% to 62%; P=0.035), stroke 84% (CI, 32% to 157%; P<0.001), and total mortality 41% (CI, 7% to 84%; P=0.013). Risk for myocardial infarction was 44% higher (CI, -5% to 120%; P=0.089). The risks in the losartan group also increased with increasing quartile, but were lower than in the atenolol group, and differences between the highest and lowest quartiles were not significant: composite end point 12% (CI, -13% to 44%; P>0.2), stroke -5% (CI, -34% to 37%; P>0.2), myocardial infarction 30% (CI, -13% to 94%; P>0.2), and total mortality 32% (CI, -1% to 76%; P=0.062). In patients with hypertension and left ventricular hypertrophy in the LIFE study, there were significantly higher risks, adjusted for the Framingham risk score, for the primary composite end point, stroke, and total mortality in the highest versus lowest quartile of pulse pressure with atenolol-based treatment. The risks in the losartan group also increased with increasing pulse pressure quartile, but were lower than those in the atenolol group, and were not significant.

The Effects of Losartan Compared to Atenolol on Stroke in Patients With Isolated Systolic Hypertension and Left Ventricular Hypertrophy. The LIFE Study

The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study reported that a losartan-based antihypertensive regimen reduced cardiovascular morbidity and mortality (composite of cardiovascular death, stroke, and myocardial infarction) more than therapy based on atenolol in patients with left ventricular hypertrophy and isolated systolic hypertension (ISH). Patients aged 55-80 years with blood pressures 160-200/<90 mm Hg were followed for a mean of 4.7 years. Blood pressure was similarly reduced in the losartan (n=660) and atenolol (n=666) ISH groups. There were 88 (6.6%) patients who experienced a stroke, 18 of which were fatal. Of patients experiencing strokes, 72.7% had an ischemic stroke. ISH patients in LIFE compared to the non-ISH group had a higher incidence of any stroke and embolic stroke, and similar incidences of fatal, atherosclerotic, and hemorrhagic/other strokes. The incidence of any stroke (40% risk reduction [RR], p=0.02), fatal stroke (70% RR, p=0.035), and atherothrombotic stroke (45% RR, p=0.022) was significantly lower in losartan-treated compared to the atenolol-treated patients. The 36% RR for embolic strokes in the losartan group was not statistically significantly (p=0.33) different from the atenolol group. These data suggest that losartan-based treatment is more effective than an atenolol-based treatment for patients with ISH and a high risk for stroke.

Nebivolol decreases oxidative stress in essential hypertensive patients and increases nitric oxide by reducing its oxidative inactivation

To obtain further insight into the mechanism underlying the vasodilator effect of nebivolol. Since oxidative inactivation of nitric oxide (NO) is regarded as an important cause of its decreased biological activity, we studied (1) the effect of nebivolol on some oxidative parameters in essential hypertensive patients; (2) the effect of plasma of nebivolol-treated patients on reactive oxygen species production and NO availability in endothelial cells. A total of 20 healthy subjects and 20 matched essential hypertensive patients treated with atenolol or nebivolol according to a double-blind, randomized design participated in the study. We measured low-density lipoprotein (LDL) and plasma hydroperoxides, 8-isoprostanes, oxidized LDL, susceptibility of LDL to oxidation (lag phase) and LDL vitamin E and the effect of plasma of nebivolol- and atenolol-treated patients on reactive oxygen species production and NO availability in endothelial cells exposed to oxidative stress. In hypertensive patients, nebivolol and atenolol significantly reduced blood pressure values after 4 weeks of treatment. Plasma and LDL hydroperoxides, plasma 8-isoprostanes, plasma ox-LDL and LDL lag phase were significantly improved only in the patients receiving nebivolol compared with the atenolol group. Similarly there was a reduction of reactive oxygen species (ROS) and O2*- concentration in endothelial cells exposed to oxidative stress after incubation of the cells with plasma of the patients enrolled in the trial only in the patients receiving nebivolol compared to atenolol group. Furthermore, the reduction of basal and stimulated NO induced by oxidative stress in endothelial cells was significantly lower in the patients receiving nebivolol compared to atenolol group. The findings of the present study indicate that nebivolol, through its antioxidant properties, increases NO also by decreasing its oxidative inactivation.

Cardiovascular morbidity and mortality in hypertensive patients with a history of atrial fibrillation: The Losartan Intervention For End point reduction in hypertension (LIFE) study

We assessed the impact of antihypertensive treatment in hypertensive patients with electrocardiographic (ECG) left ventricular (LV) hypertrophy and a history of atrial fibrillation (AF). Optimal treatment of hypertensive patients with AF to reduce the risk of cardiovascular morbidity and mortality remains unclear. As part of the Losartan Intervention For End point reduction in hypertension (LIFE) study, 342 hypertensive patients with AF and LV hypertrophy were assigned to losartan- or atenolol-based therapy for 1,471 patient-years of follow-up. The primary composite end point (cardiovascular mortality, stroke, and myocardial infarction) occurred in 36 patients in the losartan group versus 67 in the atenolol group (hazard ratio [HR] = 0.58, 95% confidence interval [CI] 0.39 to 0.88, p = 0.009). Cardiovascular deaths occurred in 20 versus 38 patients in the losartan and atenolol groups, respectively (HR = 0.58, 95% CI 0.33 to 0.99, p = 0.048). Stroke occurred in 18 versus 38 patients (HR = 0.55, 95% CI 0.31 to 0.97, p = 0.039), and myocardial infarction in 11 versus 8 patients (p = NS). Losartan-based treatment led to trends toward lower all-cause mortality (30 vs. 49, HR = 0.67, 95% CI 0.42 to 1.06, p = 0.090) and fewer pacemaker implantations (5 vs. 15, p = 0.065), whereas hospitalization for heart failure took place in 15 versus 26 patients and sudden cardiac death in 9 versus 17, respectively (both p = NS). The benefit of losartan was greater in patients with AF than those with sinus rhythm for the primary composite end point (p = 0.019) and cardiovascular mortality (p = 0.039). Losartan is more effective than atenolol-based therapy in reducing the risk of the primary composite end point of cardiovascular morbidity and mortality as well as stroke and cardiovascular death in hypertensive patients with ECG LV hypertrophy and AF.

Metoprolol and atenolol in mild-to-moderate chronic heart failure: The comparison of survival benefit

The clinical end-point of all causes of mortality and cardiovascular hospitalisation (combined end-points) is a widely accepted indicator of heart failure survival. The primary aim of this study was to examine the effects of metoprolol and atenolol on combined end-points in patients with mild-to-moderate heart failure. This study was designed to be comparative, prospective, and random. The criteria for study inclusion were: age of 70 years or less, New York Heart Association (NYHA) Functional Class II and III, and an ejection fraction of the left ventricle of 40% or less. The patients (a total of 150) on therapy with angiotensin-converting enzyme inhibitor and a diuretic were randomised into three numerically equal therapy groups: 1) an atenolol group; 2) a metoprolol group; and 3) a control group (without beta-blockers). The follow-up period was 12 months. The results were analysed using: the hi-square test, variance analyses, Kaplan-Meier's model, Wilcox's statistics, and Cox's model. The cumulative survival rate for patients treated with metoprolol was 88%, 78% for patients treated with atenolol, and 48% for patients from the control group. It is clear that the cumulative survival rate for patients treated with metoprolol and atenolol is significantly higher compared to patients from the control group. In addition, the survival rate of patients treated with metoprolol was considerably higher compared to the survival rate of patients treated with atenolol. Metoprolol has significantly reduced the relative risk of combined end-points (71%) compared to atenolol (53%). The results of this comparative study clearly indicate that metoprolol and atenolol have a favourable effect on the survival rate of patients with chronic heart failure. In addition, metoprolol is considerably more effective than atenolol.

Ischemia-Induced Norepinephrine Release, but not Norepinephrine-Derived Free Radicals, Contributes to Myocardial Ischemia - Reperfusion Injury

Norepinephrine (NE)-derived free radicals may contribute to myocyte injury after ischemia -reperfusion, so the influence of sympathetic denervation on myocardial ischemia - reperfusion injury was investigated in the present study. Cardiac sympathetic denervation was produced in Wistar rats by a solution of 10% phenol 1 week before ischemia. Atenolol (0.5 mg/kg) was intravenously administered 10 min before the coronary occlusion. The left coronary artery was occluded for 30 min and thereafter reperfused. Cardiac interstitial fluid was collected by a microdialysis probe and free radicals in dialysate were determined by electron paramagnetic resonance (EPR) spin trapping, using 5,5-dimethyl-1-pyrroline-N-oxide as a spin trap. The ratio of infarct size to the ischemic area at risk (I/R) was decreased in both the phenol and atenolol groups compared with control (28.5+/-11.3, 31.8+/-10.7 vs 50.6+/-14.7%, p<0.05). During the coronary occlusion, concentrations of interstitial NE increased markedly in the control and atenolol groups, but was unchanged in the phenol group. EPR signal intensity (relative value to internal standard) was maximal at 1 h after reperfusion and was similar in the phenol and control groups (0.32+/-0.15 vs 0.45+/-0.19). Cardiac denervation protected myocyte against ischemia-reperfusion injury through decreasing direct NE toxicity, but not through decreasing NE-derived free radicals.

Different Effects on Inhibition of Cardiac Hypertrophy in Spontaneously Hypertensive Rats by Monotherapy and Combination Therapy of Adrenergic Receptor Antagonists and/or the Angiotensin II Type 1 Receptor Blocker under Comparable Blood Pressure Reduction

To confirm that alpha1, beta adrenoceptor antagonists and angiotensin II type 1 receptor blockers (ARBs) have different abilities to attenuate progressive cardiac hypertrophy despite their comparable lowering of blood pressure, we compared the effect of these agents alone or in combination on hypertensive cardiac hypertrophy. Eight-week-old spontaneously hypertensive rats (SHR) were divided into 7 groups. Single administration of doxazosin, atenolol, or losartan, or half-dose combinations of these drugs were given orally for 6 weeks. The control group did not receive any drugs. The heart weight-to-body weight ratio (HW/BW), left ventricular mass index (LVMI), plasma brain natriuretic peptide (BNP) and left ventricular BNP mRNA expression were measured after 6-week administration. Blood pressure did not differ among the drug-treated groups, all of which showed lower blood pressure than the control group. The HW/BW and LVMI of the drug-treated groups, except the doxazosin group, were lower than in the control group. Moreover, the LVMI values of the groups receiving losartan were significantly lower than those in the groups without losartan (p < 0.05). Plasma BNP of the drug-treated groups was lower than that in the control group (p < 0.05). The left ventricular BNP mRNA expression of the drug-treated groups, except the doxazosin group, was lower than that in the control group. The atenolol group showed a higher level of BNP mRNA than the groups receiving losartan monotherapy or combination therapies (p < 0.05). In conclusion, the ARB had the strongest attenuating effect on the development of hypertensive cardiac hypertrophy, and the alpha1 and beta adrenergic receptor blockers were more effective in combination than as monotherapies in SHR.