Triple combination therapy to improve blood pressure control: experience with olmesartan-amlodipine-hydrochlorothiazide therapy

INTRODUCTION

Effective treatment of hypertension is a key strategy for preventing and reducing the burden of hypertension-related cardiovascular diseases. In spite of these well-established concepts, hypertension remains poorly controlled, worldwide. Among the different pharmacological strategies required to improve blood pressure (BP) control, a more extensive use of combination therapy is progressively emerging as a cornerstone of a more effective treatment of hypertension. Among different drug combinations currently available for the clinical management of hypertension, those based on the association of drugs inhibiting the renin-angiotensin system, thiazide diuretics and calcium channel blockers have demonstrated to be very effective in lowering both systolic and diastolic, clinic and 24-h ambulatory BP levels with a good tolerability and safety profile.

AREAS COVERED

In the present manuscript the authors provide an overview of the evidence supporting the use of triple combination therapy with different classes of antihypertensive drugs, with a particular focus on those based on olmesartan medoxomil, a thiazide diuretic (hydrochlorothiazide) and a calcium channel blocker (amlodipine besylate).

EXPERT OPINION

Available data indicate that triple combination therapy based on olmesartan provides effective and sustained clinical and 24-h BP control in a high proportion of individuals among a broad range of hypertensive patients.

QRS duration and QRS fractionation on surface electrocardiogram are markers of right ventricular dysfunction and atrialization in patients with Ebstein anomaly

BACKGROUND

Ebstein anomaly is a rare and heterogeneous congenital heart defect affecting the tricuspid valve and right ventricular (RV) myocardium. Few studies have analysed the electrocardiographic features of Ebstein anomaly and none has addressed correlations with disease severity.

METHODS

Patients with Ebstein anomaly who had undergone electrocardiography and cardiac magnetic resonance (CMR) within 6 weeks between 2001 and 2009 were included. Exclusion criteria were: associated congenital cardiac defect, previous RV myoplasty and/or reduction surgery, class I anti-arrhythmic drug therapy, and paced/pre-excited QRS. Standard electrocardiogram (ECG) findings were correlated with CMR-based RV measures and clinical profile.

RESULTS

The mean age of the 63 study patients was 22 ± 13 years. An RV conduction delay (rsR' pattern in right precordial leads) was present in 45 patients (71%). The QRS duration correlated with anatomic RV diastolic volume (r = +0.56, P < 0.0001) and inversely with RV ejection fraction (EF; r = -0.62, P < 0.0001). The presence of QRS fractionation predicted greater atrialized RV volume (80 ± 31 vs. 45 ± 37 mL/m(2), P < 0.001). Normal QRS duration was associated with smaller anatomic RV diastolic volume (150 ± 57 vs. 256 ± 100 mL/m(2); P < 0.0001), higher RV EF (48 ± 6 vs. 34 ± 14%; P < 0.0001), higher oxygen consumption (VO(2)) at cardiopulmonary exercise (25.8 vs. 21.8 mL/kg/min, P = 0.05) and lower incidence of oxygen desaturation with exercise (25 vs. 65%, P = 0.02).

CONCLUSION

Delayed and prolonged depolarization of the RV is common in patients with Ebstein anomaly. The QRS duration is a marker of RV enlargement and dysfunction. QRS fractionation is associated with a greater atrialized RV volume. A preserved surface ECG identifies a subset of patients with Ebstein anomaly with mild morphological and functional abnormalities and better clinical profile.

Lack of Influence of the Androgen Receptor Gene CAG-Repeat Polymorphism on Clinical and Electrocardiographic Manifestations of the Brugada Syndrome in Man

Background

Clinical studies suggest that testosterone (T) plays an important role in the male predominance of the clinical manifestations of the Brugada syndrome (BS). However, no statistically significant correlations have been observed between T levels and electrocardiogram (ECG) parameters in the BS patients. We investigated whether the hormonal pattern and the variation within CAG repeat polymorphism in exon 1 of the androgen receptor (AR) gene, affecting androgen sensitivity, are associated with the Brugada ECG phenotype in males.

Methods and Results

16 male patients with BS (mean age 45.06 ± 11.3 years) were studied. 12-lead ECG was recorded. Blood levels of follicle-stimulating hormone, luteinizing hormone, prolactin, testosterone, free-T, dihydrotestosterone, 17-β-estradiol, estrone, 3-alpha-androstanediol-glucuronide, delta-4-androstenedione, dehydroepiandrosterone sulphate, progesterone, 17-hydroxyprogesterone, and sex hormone binding globulin were assayed. Genotyping of CAG repeats on DNA extracted from leukocytes was carried out. No relationship was found between hormone values and ECG parameters of BS. BS patients showed the CAG length normally recognized in the human polymorphism range and the number of CAG repeats did not correlate with the ECG pattern of BS.

Conclusions

The AR CAG repeat length does not correlate with the ECG features of the patients affected by BS. The search for genes downstream AR activation as possibly responsible for the increased risk of spontaneous arrhythmias in BS males after puberty is warranted.

[Polytherapy in cardiovascular prevention: open issues]

Despite the considerable advances in preventive treatment achieved over the last two decades, the increasing burden of cardiovascular disease represents an urgent need for new therapeutic strategies to reduce cardiovascular mortality and morbidity. The current pandemic of obesity, hypertension and diabetes, as a result of unhealthy lifestyle and dietary habits together with predisposing genetic backgrounds, is the main cause of increased cardiovascular mortality and raised overall health expenditure. Despite the growing number of cardiovascular prevention campaigns, the control of cardiovascular risk factors remains largely unsatisfactory worldwide. Unhealthy lifestyles lead to an increased consumption of drugs to achieve target levels of cardiovascular risk factors, namely blood pressure and low-density lipoprotein cholesterol. This phenomenon results in a disproportionate increase in the number of cardiovascular drugs, already in the early stages of disease. Despite current guidelines encourage combination therapies in cardiovascular prevention, the adoption of polytherapy, commonly defined as the use of 5 or more drugs, is extremely frequent and is often paradoxically unsuccessful due to poor patient education and adherence, increased adverse effects and inappropriate drug prescribing. Moreover, increased life-expectancy resulting from early treatment of myocardial infarction and improved heart failure management has led to an older population characterized by an increased prevalence of comorbid conditions. This is a further reason for increased prescription of drugs leading to an impairment of patient adherence and increased adverse effects. In order to overcome the emerging problem of polytherapy, the use of a single "polypill" containing a combination of drugs for cardiovascular prevention has been postulated. Such an approach is providing promising results in the management of hypertension and dyslipidemia. However, available evidence is still preliminary and prospective data on cardiovascular outcomes are still lacking. This present article proposes a critical analysis of some open issues related to polytherapy in cardiovascular prevention.

Preventing cardiovascular events with angiotensin II receptor blockers: a closer look at telmisartan and valsartan

Angiotensin II receptor blockers (ARBs) inhibit the renin-angiotensin system. As a result, these agents provide beneficial effects in terms of cardiovascular (CV) and renal protection, independent of their blood pressure-lowering effects. Telmisartan and valsartan are the most intensively studied ARBs for the effects on CV outcomes. Randomized clinical trials assessing morbidity and mortality end points have included a range of patient types, including those with hypertension, hypertension with Type 2 diabetes, high CV risk without hypertension, ischemic heart disease, stroke and heart failure. Few head-to-head comparisons between telmisartan and valsartan have been performed. However, some blood pressure-independent properties of these two ARBs can be scrutinized from separate studies in the available literature.

Abstract 533: MAS Receptor Activation Contributes to the Improvement of Vascular Remodeling During Chronic Angiotensin II Type 1 Receptor Blockade in Angiotensin II Type 2 Receptor Knockout Mice

Angiotensin (Ang)-(1-7) through MAS receptor may counteract the Ang II-induced actions. We previously demonstrated that the Ang receptor blocker olmesartan (OLM) improved vascular remodeling in SHR in part through the activation of MAS receptor. Here, we hypothesized that such an effect is independent of Ang II type 2 (AT2) receptor activation. AT2-knockout mice (AT2-K/O, 12 weeks old, n=6 per group) were treated with vehicle (control) or Ang (1-7) (15,5 pmol/kg/min) or Ang II (400 ng/kg/min) ± OLM (10 mg/kg/day) ± the MAS antagonist A-779 (11 pmol/min) for 14 days. BP was measured by tail-cuff method. In isolated mesenteric arteries pre-contracted with norepinephrine (10 μM) endothelium -dependent and -independent relaxation was assessed by dose-response curves to acetylcholine (1 nM to 100 μM) and SNP (10 nM to 1 mM) respectively. Mesenteric arteries media-to-lumen ratio (M/L) and cross sectional area (CSA) were evaluated on pressurized preparations. MAS expression in aorta was evaluated by immunoblotting. Ang II infusion increased BP in AT2-K/O (+20% vs control mice, P<0.05). OLM reduced BP in Ang II-infused mice (104.8±4.4 mmHg vs 121.3±2.8 mmHg, respectively, P<0.05). A-779 had no effect on BP in Ang II-infused mice treated with OLM. Ang (1-7) did not lower BP in AT2-K/O. Endothelium -dependent and -independent relaxations were similar in treated and control mice. M/L was similar in Ang II-infused and control mice. OLM significantly reduced M/L in Ang II-infused AT2-K/O (5.45±0.12 % vs 7.01±0.4%, respectively, -23%, P<0.05). A-779 increased M/L in Ang II-infused AT2-K/O treated with OLM (+18%, P<0.05). Ang (1-7) reduced M/L in AT2-K/O (-21%, P<0.05). CSA was similar in all the groups. MAS expression was similar in Ang II-infused and control mice. MAS expression was increased by OLM in Ang II-infused mice (+108%, P<0.05). A-779 prevented MAS increase in Ang II-infused mice treated with OLM. Ang (1-7) increased MAS expression in AT2-K/O (+81%, P<0.05). In conclusion OLM reduced M/L and improved vascular remodeling in AT2-K/O in part through the increased expression and activation of MAS, independently of BP reduction. Such an effect is indeed independent of AT2 activation, as MAS is functionally active in the vasculature of AT2-K/O.

A survey on blood pressure levels and hypertension control in a sample of the Italian general population

BACKGROUND

Hypertension represents a major cardiovascular risk factor with relevant consequences on morbidity and mortality in the general population. An optimal control of blood pressure (BP) is far from being achieved.

AIM

The objective of this study was to explore awareness of BP levels, prevalence of risk factors and status of hypertension control in a sample of the Italian general population.

METHODS

Subjects aged 18 years or older were enrolled on a voluntary basis during the 7th and 8th World Hypertension Days at our hospital centre, S. Andrea Hospital in Rome, and at other hospitals throughout the Italian Lazio region. Along with BP measurement, a short questionnaire was completed at the time of the interview.

RESULTS

Of 1165 individuals enrolled into the analysis, 71.7% were aware of their BP levels (82.5% among hypertensive patients). Within the whole cohort, 31.9% of subjects were under antihypertensive treatment, while the overall rate of subjects found to be hypertensive patients at our visit was 52.9% (n = 616). Among hypertensive patients taking antihypertensive drugs, 47.1% had controlled BP values with the remaining 52.9% showing uncontrolled hypertension. Mean systolic blood pressure (SBP) was 138.2 ± 20.7 mmHg and mean diastolic blood pressure (DBP) was 80.4 ± 11.3 mmHg in subjects receiving antihypertensive treatment. Among older hypertensive patients (71-94 years of age), only 76.9% were under treatment. Hypertensive males were more frequently treated than females in all age groups (p = 0.001). Smoking habit negatively affected efficacy of antihypertensive therapy in the age groups of 48-53 and 54-62 years (p = 0.008 and p = 0.01, respectively). Diabetic patients had higher mean SBP values than non-diabetic subjects (137.3 ± 22.1 vs 129.3 ± 18.2 mmHg, p = 0.02).

CONCLUSION

The results of our survey strongly support the need for a continuing educational effort aimed at providing correct advertisement of healthy lifestyles and awareness of adequate BP control. Based on our observations, particular attention has to be paid to women, younger subjects, elderly subjects and diabetic patients in order to reach appropriate BP control and reduction of cardiovascular risk in these subject categories.

Influence of rs5065 atrial natriuretic peptide gene variant on coronary artery disease

OBJECTIVES

The aim of this study was to investigate the impact of rs5065 atrial natriuretic peptide (ANP) gene variant on coronary artery disease (CAD) and its outcomes and to gain potential mechanistic insights on the association with CAD.

BACKGROUND

Either modified ANP plasma levels or peptide structural alterations have been involved in development of cardiovascular events.

METHODS

Three hundred ninety-three control subjects and 1,004 patients undergoing coronary angiography for suspected CAD (432 stable angina [SA], 572 acute coronary syndrome [ACS]) were genotyped for rs5065 ANP gene variant. Data in SA and ACS groups were replicated in an independent population of 482 stable angina patients (rSA) and of 675 ACS patients, respectively. Clinical follow-up was available for both SA and rSA patients. Plasma N-terminal-proANP, myeloperoxidase, lipoprotein-associated phospholipase A2, and oxidized low-density lipoprotein were assessed in a subgroup of rSA patients.

RESULTS

rs5065 minor allele (MA) was an independent predictor of ACS (odds ratio: 1.90; 95% confidence interval: 1.40 to 2.58, p < 0.001). At follow-up, rs5065 MA was independently associated with a significantly higher rate of major adverse cardiovascular events in the SA group, p < 0.001. Data were replicated in the rSA group at follow-up (p = 0.008). Cox proportional hazard analysis tested by 4 models confirmed higher major adverse cardiovascular events risk in rs5065 MA carriers in both SA and rSA cohorts. Significantly higher myeloperoxidase levels were detected in rs5065 MA carriers (n = 597 [345 to 832 μg/l] vs. n = 488 [353 to 612 μg/l], p = 0.038). No association of rs5065 was observed with N-terminal-proANP levels.

CONCLUSIONS

The MA of rs5065 ANP gene variant associates with increased susceptibility to ACS and has unfavorable prognostic value in CAD.

Global cardiovascular risk management in different Italian regions: an analysis of the Evaluation of Final Feasible Effect of Control Training and Ultra Sensitisation (EFFECTUS) educational program

BACKGROUND AND AIM

The Final Evaluation Feasible Effect of Ultra Control Training and Sensitization (EFFECTUS) is an educational program, aimed at improving global CV risk stratification and management in Italy. The present study evaluates differences on clinical approach to global CV risk among physicians involved in the EFFECTUS program and stratified in three geographical macro-areas (North, Center, South) of our Country.

METHODS AND RESULTS

Physicians were asked to submit data already available in their medical records, covering the first 10 adult outpatients, consecutively seen in the month of May 2006. Overall, 1.078 physicians (27% females, aged 50 ± 7 years) collected data of 9.904 outpatients (46.5% females, aged 67 ± 9 years), among which 3.219 (32.5%) were residents in Northern, 3.652 (36.9%) in Central and 3.033 (30.6%) in Southern Italy. A significantly higher prevalence of major CV risk factors, including obesity, physical inactivity, hypertension and diabetes, was recorded in Southern than in other areas. Accordingly, Southern physicians more frequently prescribed antihypertensive, glucose and lipid lowering agents than other physicians, who paid significantly more attention to life-style changes in their clinical practice.

CONCLUSIONS

This analysis of the EFFECTUS study demonstrates a high prevalence of CV risk factors in Italy, particularly in Southern areas, and indicates some important discrepancies in the clinical management of global CV risk among physcians working in different Italian regions.

Gene silencing of the mitochondrial adaptor p66(Shc) suppresses vascular hyperglycemic memory in diabetes

RATIONALE

Hyperglycemic memory may explain why intensive glucose control has failed to improve cardiovascular outcomes in patients with diabetes. Indeed, hyperglycemia promotes vascular dysfunction even after glucose normalization. However, the molecular mechanisms of this phenomenon remain to be elucidated.

OBJECTIVE

The present study investigated the role of mitochondrial adaptor p66(Shc) in this setting.

METHODS AND RESULTS

In human aortic endothelial cells (HAECs) exposed to high glucose and aortas of diabetic mice, activation of p66(Shc) by protein kinase C βII (PKCβII) persisted after returning to normoglycemia. Persistent p66(Shc) upregulation and mitochondrial translocation were associated with continued reactive oxygen species (ROS) production, reduced nitric oxide bioavailability, and apoptosis. We show that p66(Shc) gene overexpression was epigenetically regulated by promoter CpG hypomethylation and general control nonderepressible 5-induced histone 3 acetylation. Furthermore, p66(Shc)-derived ROS production maintained PKCβII upregulation and PKCβII-dependent inhibitory phosphorylation of endothelial nitric oxide synthase at Thr-495, leading to a detrimental vicious cycle despite restoration of normoglycemia. Moreover, p66(Shc) activation accounted for the persistent elevation of the advanced glycated end product precursor methylglyoxal. In vitro and in vivo gene silencing of p66(Shc), performed at the time of glucose normalization, blunted ROS production, restored endothelium-dependent vasorelaxation, and attenuated apoptosis by limiting cytochrome c release, caspase 3 activity, and cleavage of poly (ADP-ribose) polymerase.

CONCLUSIONS

p66(Shc) is the key effector driving vascular hyperglycemic memory in diabetes. Our study provides molecular insights for the progression of diabetic vascular complications despite glycemic control and may help to define novel therapeutic targets.

Rationale for triple fixed-dose combination therapy with an angiotensin II receptor blocker, a calcium channel blocker, and a thiazide diuretic

Hypertension is a growing global health problem, and is predicted to affect 1.56 billion people by 2025. Treatment remains suboptimal, with control of blood pressure achieved in only 20%-35% of patients, and the majority requiring two or more antihypertensive drugs to achieve recommended blood pressure goals. To improve blood pressure control, the European hypertension guidelines recommend that angiotensin II receptor blockers (ARBs) or angiotensin-converting enzyme inhibitors (ACEIs) are combined with calcium channel blockers (CCBs) and/or thiazide diuretics. The rationale for this strategy is based, in part, on their different effects on the renin-angiotensin system, which improves antihypertensive efficacy. Data from a large number of trials support the efficacy of ACEIs or ARBs in combination with CCBs and/or hydrochlorothiazide (HCTZ). Combining two different classes of antihypertensive drugs has an additive effect on lowering of blood pressure, and does not increase adverse events, with the ARBs showing a tolerability advantage over the ACEIs. Among the different ARBs, olmesartan medoxomil is available as a dual fixed-dose combination with either amlodipine or HCTZ, and the increased blood pressure-lowering efficacy of these two combinations is proven. Triple therapy is required in 15%-20% of treated uncontrolled hypertensive patients, with a renin-angiotensin system blocker, CCB, and thiazide diuretic considered to be a rational combination according to the European guidelines. Olmesartan, amlodipine, and HCTZ are available as a triple fixed-dose combination, and significant blood pressure reductions have been observed with this regimen compared with the possible dual combinations. The availability of these fixed-dose combinations should lead to improvement in blood pressure control and aid compliance with long-term therapy, optimizing the management of this chronic condition.

Is reactivation of autophagy a possible therapeutic solution for obesity and metabolic syndrome?

The molecular mechanism regulating the cardiomyocyte response to energy stress has been a hot topic in cardiac research in recent years, since this mechanism could be targeted for treatment of patients with ischemic heart disease. We have shown recently that the activity of RAS homolog enriched in brain (RHEB), a small GTP binding protein, is inhibited in response to glucose deprivation (GD) in cardiomyocytes and ischemia in the mouse heart. This is a physiological adaptation, since it inhibits complex 1 of the mechanistic target of rapamycin (MTORC1) and activates autophagy, thereby promoting cell survival during GD and prolonged ischemia. Importantly, the physiological inhibition of RHEB-MTORC1 signaling during myocardial ischemia is impaired in the presence of obesity and metabolic syndrome caused by high-fat diet (HFD) feeding, leading to a dramatic increase in ischemic injury. Although MTORC1 and autophagy can be regulated through RHEB-independent mechanisms, such as the AMPK-dependent phosphorylation of RPTOR and ULK1, RHEB appears to be critical in the regulation of MTORC1 and autophagy during ischemia in cardiomyocytes, and its dysregulation is relevant to human disease. Here we discuss the biological relevance of the dysregulation of RHEB-MTORC1 signaling and the suppression of autophagy in obesity and metabolic syndrome.