ADEPT: Addition of the AT1 receptor antagonist eprosartan to ACE inhibitor therapy in chronic heart failure trial: hemodynamic and neurohormonal effects

Beta-blockers and inhibitors of the renin-angiotensin aldosterone system for chronic heart failure with preserved ejection fraction

BACKGROUND

Beta-blockers and inhibitors of the renin-angiotensin-aldosterone system improve survival and reduce morbidity in people with heart failure with reduced left ventricular ejection fraction (LVEF); a review of the evidence is required to determine whether these treatments are beneficial for people with heart failure with preserved ejection fraction (HFpEF).

OBJECTIVES

To assess the effects of beta-blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, angiotensin receptor neprilysin inhibitors, and mineralocorticoid receptor antagonists in people with HFpEF.

SEARCH METHODS

We updated searches of CENTRAL, MEDLINE, Embase, and one clinical trial register on 14 May 2020 to identify eligible studies, with no language or date restrictions. We checked references from trial reports and review articles for additional studies.  SELECTION CRITERIA: We included randomised controlled trials with a parallel group design, enrolling adults with HFpEF, defined by LVEF greater than 40%.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 41 randomised controlled trials (231 reports), totalling 23,492 participants across all comparisons. The risk of bias was frequently unclear and only five studies had a low risk of bias in all domains. Beta-blockers (BBs) We included 10 studies (3087 participants) investigating BBs. Five studies used a placebo comparator and in five the comparator was usual care. The mean age of participants ranged from 30 years to 81 years. A possible reduction in cardiovascular mortality was observed (risk ratio (RR) 0.78, 95% confidence interval (CI) 0.62 to 0.99; number needed to treat for an additional benefit (NNTB) 25; 1046 participants; three studies), however, the certainty of evidence was low. There may be little to no effect on all-cause mortality (RR 0.82, 95% CI 0.67 to 1.00; 1105 participants; four studies; low-certainty evidence). The effects on heart failure hospitalisation, hyperkalaemia, and quality of life remain uncertain. Mineralocorticoid receptor antagonists (MRAs) We included 13 studies (4459 participants) investigating MRA. Eight studies used a placebo comparator and in five the comparator was usual care. The mean age of participants ranged from 54.5 to 80 years. Pooled analysis indicated that MRA treatment probably reduces heart failure hospitalisation (RR 0.82, 95% CI 0.69 to 0.98; NNTB = 41; 3714 participants; three studies; moderate-certainty evidence). However, MRA treatment probably has little or no effect on all-cause mortality (RR 0.91, 95% CI 0.78 to 1.06; 4207 participants; five studies; moderate-certainty evidence) and cardiovascular mortality (RR 0.90, 95% CI 0.74 to 1.11; 4070 participants; three studies; moderate-certainty evidence). MRA treatment may have little or no effect on quality of life measures (mean difference (MD) 0.84, 95% CI -2.30 to 3.98; 511 participants; three studies; low-certainty evidence). MRA treatment was associated with a higher risk of hyperkalaemia (RR 2.11, 95% CI 1.77 to 2.51; number needed to treat for an additional harmful outcome (NNTH) = 11; 4291 participants; six studies; high-certainty evidence). Angiotensin-converting enzyme inhibitors (ACEIs) We included eight studies (2061 participants) investigating ACEIs. Three studies used a placebo comparator and in five the comparator was usual care. The mean age of participants ranged from 70 to 82 years. Pooled analyses with moderate-certainty evidence suggest that ACEI treatment likely has little or no effect on cardiovascular mortality (RR 0.93, 95% CI 0.61 to 1.42; 945 participants; two studies), all-cause mortality (RR 1.04, 95% CI 0.75 to 1.45; 1187 participants; five studies) and heart failure hospitalisation (RR 0.86, 95% CI 0.64 to 1.15; 1019 participants; three studies), and may result in little or no effect on the quality of life (MD -0.09, 95% CI -3.66 to 3.48; 154 participants; two studies; low-certainty evidence). The effects on hyperkalaemia remain uncertain. Angiotensin receptor blockers (ARBs) Eight studies (8755 participants) investigating ARBs were included. Five studies used a placebo comparator and in three the comparator was usual care. The mean age of participants ranged from 61 to 75 years. Pooled analyses with high certainty of evidence suggest that ARB treatment has little or no effect on cardiovascular mortality (RR 1.02, 95% 0.90 to 1.14; 7254 participants; three studies), all-cause mortality (RR 1.01, 95% CI 0.92 to 1.11; 7964 participants; four studies), heart failure hospitalisation (RR 0.92, 95% CI 0.83 to 1.02; 7254 participants; three studies), and quality of life (MD 0.41, 95% CI -0.86 to 1.67; 3117 participants; three studies). ARB was associated with a higher risk of hyperkalaemia (RR 1.88, 95% CI 1.07 to 3.33; 7148 participants; two studies; high-certainty evidence). Angiotensin receptor neprilysin inhibitors (ARNIs) Three studies (7702 participants) investigating ARNIs were included. Two studies used ARBs as the comparator and one used standardised medical therapy, based on participants' established treatments at enrolment. The mean age of participants ranged from 71 to 73 years. Results suggest that ARNIs may have little or no effect on cardiovascular mortality (RR 0.96, 95% CI 0.79 to 1.15; 4796 participants; one study; moderate-certainty evidence), all-cause mortality (RR 0.97, 95% CI 0.84 to 1.11; 7663 participants; three studies; high-certainty evidence), or quality of life (high-certainty evidence). However, ARNI treatment may result in a slight reduction in heart failure hospitalisation, compared to usual care (RR 0.89, 95% CI 0.80 to 1.00; 7362 participants; two studies; moderate-certainty evidence). ARNI treatment was associated with a reduced risk of hyperkalaemia compared with valsartan (RR 0.88, 95% CI 0.77 to 1.01; 5054 participants; two studies; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

There is evidence that MRA and ARNI treatment in HFpEF probably reduces heart failure hospitalisation but probably has little or no effect on cardiovascular mortality and quality of life. BB treatment may reduce the risk of cardiovascular mortality, however, further trials are needed. The current evidence for BBs, ACEIs, and ARBs is limited and does not support their use in HFpEF in the absence of an alternative indication. Although MRAs and ARNIs are probably effective at reducing the risk of heart failure hospitalisation, the treatment effect sizes are modest. There is a need for improved approaches to patient stratification to identify the subgroup of patients who are most likely to benefit from MRAs and ARNIs, as well as for an improved understanding of disease biology, and for new therapeutic approaches.

Beta-blockers and inhibitors of the renin-angiotensin aldosterone system for chronic heart failure with preserved ejection fraction

BACKGROUND

Beta-blockers and inhibitors of the renin-angiotensin aldosterone system improve survival and reduce morbidity in people with heart failure with reduced left ventricular ejection fraction. There is uncertainty whether these treatments are beneficial for people with heart failure with preserved ejection fraction and a comprehensive review of the evidence is required.

OBJECTIVES

To assess the effects of beta-blockers, angiotensin converting enzyme inhibitors, angiotensin receptor blockers, angiotensin receptor neprilysin inhibitors, and mineralocorticoid receptor antagonists in people with heart failure with preserved ejection fraction.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase and two clinical trial registries on 25 July 2017 to identify eligible studies. Reference lists from primary studies and review articles were checked for additional studies. There were no language or date restrictions.

SELECTION CRITERIA

We included randomised controlled trials with a parallel group design enrolling adult participants with heart failure with preserved ejection fraction, defined by a left ventricular ejection fraction of greater than 40 percent.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion and extracted data. The outcomes assessed included cardiovascular mortality, heart failure hospitalisation, hyperkalaemia, all-cause mortality and quality of life. Risk ratios (RR) and, where possible, hazard ratios (HR) were calculated for dichotomous outcomes. For continuous data, mean difference (MD) or standardised mean difference (SMD) were calculated. We contacted trialists where neccessary to obtain missing data.

MAIN RESULTS

37 randomised controlled trials (207 reports) were included across all comparisons with a total of 18,311 participants.Ten studies (3087 participants) investigating beta-blockers (BB) were included. A pooled analysis indicated a reduction in cardiovascular mortality (15% of participants in the intervention arm versus 19% in the control arm; RR 0.78; 95% confidence interval (CI) 0.62 to 0.99; number needed to treat to benefit (NNTB) 25; 1046 participants; 3 studies). However, the quality of evidence was low and no effect on cardiovascular mortality was observed when the analysis was limited to studies with a low risk of bias (RR 0.81; 95% CI 0.50 to 1.29; 643 participants; 1 study). There was no effect on all-cause mortality, heart failure hospitalisation or quality of life measures, however there is uncertainty about these effects given the limited evidence available.12 studies (4408 participants) investigating mineralocorticoid receptor antagonists (MRA) were included with the quality of evidence assessed as moderate. MRA treatment reduced heart failure hospitalisation (11% of participants in the intervention arm versus 14% in the control arm; RR 0.82; 95% CI 0.69 to 0.98; NNTB 41; 3714 participants; 3 studies; moderate-quality evidence) however, little or no effect on all-cause and cardiovascular mortality and quality of life measures was observed. MRA treatment was associated with a greater risk of hyperkalaemia (16% of participants in the intervention group versus 8% in the control group; RR 2.11; 95% CI 1.77 to 2.51; 4291 participants; 6 studies; high-quality evidence).Eight studies (2061 participants) investigating angiotensin converting enzyme inhibitors (ACEI) were included with the overall quality of evidence assessed as moderate. The evidence suggested that ACEI treatment likely has little or no effect on cardiovascular mortality, all-cause mortality, heart failure hospitalisation, or quality of life. Data for the effect of ACEI on hyperkalaemia were only available from one of the included studies.Eight studies (8755 participants) investigating angiotensin receptor blockers (ARB) were included with the overall quality of evidence assessed as high. The evidence suggested that treatment with ARB has little or no effect on cardiovascular mortality, all-cause mortality, heart failure hospitalisation, or quality of life. ARB was associated with an increased risk of hyperkalaemia (0.9% of participants in the intervention group versus 0.5% in the control group; RR 1.88; 95% CI 1.07 to 3.33; 7148 participants; 2 studies; high-quality evidence).We identified a single ongoing placebo-controlled study investigating the effect of angiotensin receptor neprilysin inhibitors (ARNI) in people with heart failure with preserved ejection fraction.

AUTHORS' CONCLUSIONS

There is evidence that MRA treatment reduces heart failure hospitalisation in heart failure with preserverd ejection fraction, however the effects on mortality related outcomes and quality of life remain unclear. The available evidence for beta-blockers, ACEI, ARB and ARNI is limited and it remains uncertain whether these treatments have a role in the treatment of HFpEF in the absence of an alternative indication for their use. This comprehensive review highlights a persistent gap in the evidence that is currently being addressed through several large ongoing clinical trials.

Prevention of remodeling in congestive heart failure due to myocardial infarction by blockade of the renin–angiotensin system

Ventricular remodeling subsequent to myocardial infarction (MI) is a complex process and is considered to be a major determinant of the clinical course of congestive heart failure (CHF). Emerging evidence suggests that activation of the renin-angiotensin system (RAS) plays an important role in post-MI ventricular remodeling; however, it is becoming clear that this is one of several neurohumoral systems that are activated in CHF. Blockade of RAS by angiotensin-converting enzyme inhibitors or angiotensin II type 1 receptor antagonists attenuates the ventricular dysfunction, but the effects of individual drugs in reducing the morbidity and mortality in CHF patients are variable. Furthermore, there is a difference of opinion as to the time of initiation of therapy with RAS blockers after the onset of MI. Since blockade of RAS partially improves cardiac function, it is suggested that a combination therapy involving RAS blockers (angiotensin-converting enzyme inhibitors or angiotensin II type 1 receptor antagonists) and agents that affect other neurohumoral systems may prove useful for improved treatment of CHF. Although activation of RAS has been shown to promote oxidative stress in experimental studies, the use of antioxidant therapy in CHF patients is controversial. Recent experimental studies have shown that ventricular remodeling in CHF is associated with remodeling of subcellular organelles such as sarcolemma, sarcoplasmic reticulum, myofibrils and extracellular matrix in terms of their molecular structure and composition. Since attenuation of remodeling in one and/or more subcellular organelles by different agents may prevent the progression of CHF, it is a challenge to develop specific drugs affecting molecular mechanisms associated with subcellular remodeling for the improved therapy of CHF.

Angiotensin receptor blockers for heart failure

BACKGROUND

Chronic heart failure (HF) is a prevalent world-wide. Angiotensin receptor blockers (ARBs) are widely prescribed for chronic HF although their role is controversial.

OBJECTIVES

To assess the benefit and harm of ARBs compared with ACE inhibitors (ACEIs) or placebo on mortality, morbidity and withdrawals due to adverse effects in patients with symptomatic HF and left ventricular systolic dysfunction or preserved systolic function.

SEARCH METHODS

Clinical trials were identified by searching CENTRAL, HTA, and DARE , (The Cochrane Library 2010 Issue 3), as well as MEDLINE (2002 to July 2010), and EMBASE (2002 to July 2010). Reference lists of retrieved articles and systematic reviews were checked for additional studies not identified by the electronic searches.

SELECTION CRITERIA

Double blind randomised controlled trials in men and women of all ages who have symptomatic (NYHA Class II to IV) HF and: 1) left ventricular systolic dysfunction, defined as left ventricular ejection fraction (LVEF) ≤40%; or 2) preserved ejection fraction, defined as LVEF >40%.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed risk of bias and extracted data from included studies.

MAIN RESULTS

Twenty two studies evaluated the effects of ARBs in 17,900 patients with a LVEF ≤40% (mean 2.2 years). ARBs did not reduce total mortality (RR 0.87 [95% CI 0.76, 1.00]) or total morbidity as measured by total hospitalisations (RR 0.94 [95% CI 0.88, 1.01]) compared with placebo.Total mortality (RR 1.05 [95% CI 0.91, 1.22]), total hospitalisations (RR 1.00 [95% CI 0.92, 1.08]), MI (RR 1.00 [95% CI 0.62, 1.63]), and stroke (RR 1.63 [0.77, 3.44]) did not differ between ARBs and ACEIs but withdrawals due to adverse effects were lower with ARBs (RR 0.63 [95% CI 0.52, 0.76]). Combinations of ARBs plus ACEIs increased the risk of withdrawals due to adverse effects (RR 1.34 [95% CI 1.19, 1.51]) but did not reduce total mortality or total hospital admissions versus ACEI alone.Two placebo-controlled studies evaluated ARBs in 7151 patients with a LVEF >40% (mean 3.7 years). ARBs did not reduce total mortality (RR 1.02 [95% CI 0.93, 1.12]) or total morbidity as measured by total hospitalisations (RR 1.00 [95% CI 0.97, 1.05]) compared with placebo. Withdrawals due to adverse effects were higher with ARBs versus placebo when all patients were pooled irrespective of LVEF (RR 1.06 [95% CI 1.01, 1.12]).

AUTHORS' CONCLUSIONS

In patients with symptomatic HF and systolic dysfunction or with preserved ejection fraction, ARBs compared to placebo or ACEIs do not reduce total mortality or morbidity. ARBs are better tolerated than ACEIs but do not appear to be as safe and well tolerated as placebo in terms of withdrawals due to adverse effects. Adding an ARB in combination with an ACEI does not reduce total mortality or total hospital admission but increases withdrawals due to adverse effects compared with ACEI alone.

Renin-angiotensin-aldosterone system blockade for cardiovascular diseases: current status

Activation of the renin-angiotensin-aldosterone system (RAAS) results in vasoconstriction, muscular (vascular and cardiac) hypertrophy and fibrosis. Established arterial stiffness and cardiac dysfunction are key factors contributing to subsequent cardiovascular and renal complications. Blockade of RAAS has been shown to be beneficial in patients with hypertension, acute myocardial infarction, chronic systolic heart failure, stroke and diabetic renal disease. An aggressive approach for more extensive RAAS blockade with combination of two commonly used RAAS blockers [ACE inhibitors (ACEIs) and angiotensin receptor blockers (ARBs)] yielded conflicting results in different patient populations. Combination therapy is also associated with more side effects, in particular hypotension, hyperkalaemia and renal impairment. Recently published ONTARGET study showed ACEI/ARB combination therapy was associated with more adverse effects without any increase in benefit. The Canadian Hypertension Education Program responded with a new warning: 'Do not use ACEI and ARB in combination'. However, the European Society of Cardiology in their updated heart failure treatment guidelines still recommended ACEI/ARB combo as a viable option. This apparent inconsistency among guidelines generates debate as to which approach of RAAS inhibition is the best. The current paper reviews the latest evidence of isolated ACEI or ARB use and their combination in cardiovascular diseases, and makes recommendations for their prescriptions in specific patient populations.

Comparing angiotensin II receptor blockers on benefits beyond blood pressure

The renin-angiotensin-aldosterone system (RAAS) is one of the main regulators of blood pressure, renal hemodynamics, and volume homeostasis in normal physiology, and contributes to the development of renal and cardiovascular (CV) diseases. Therefore, pharmacologic blockade of RAAS constitutes an attractive strategy in preventing the progression of renal and CV diseases. This concept has been supported by clinical trials involving patients with hypertension, diabetic nephropathy, and heart failure, and those after myocardial infarction. The use of angiotensin II receptor blockers (ARBs) in clinical practice has increased over the last decade. Since their introduction in 1995, seven ARBs have been made available, with approved indications for hypertension and some with additional indications beyond blood pressure reduction. Considering that ARBs share a similar mechanism of action and exhibit similar tolerability profiles, it is assumed that a class effect exists and that they can be used interchangeably. However, pharmacologic and dosing differences exist among the various ARBs, and these differences can potentially influence their individual effectiveness. Understanding these differences has important implications when choosing an ARB for any particular condition in an individual patient, such as heart failure, stroke, and CV risk reduction (prevention of myocardial infarction). A review of the literature for existing randomized controlled trials across various ARBs clearly indicates differences within this class of agents. Ongoing clinical trials are evaluating the role of ARBs in the prevention and reduction of CV rates of morbidity and mortality in high-risk patients.

ACE inhibitors, angiotensin receptor blockers and direct renin inhibitors in combination: a review of their role after the ONTARGET trial

BACKGROUND

Clinical trials have shown organ-protective effects of angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs); however, cardiovascular mortality and morbidity rates, and decline in renal function remain high. In the ONTARGET trial in patients with hypertension at high cardiovascular risk, ACE inhibitor/ARB combination therapy provided no significant clinical outcome benefits over monotherapy, and was associated with a worse safety and tolerability profile. These results raise the question of whether ACE inhibitor/ARB, direct renin inhibitor (DRI)/ACE inhibitor and DRI/ARB combinations are of clinical value.

SCOPE

Using PubMed and EMBASE databases, we conducted a systematic review of clinical trials published before June 2008 evaluating dual intervention with ACE inhibitors and ARBs, and compared these with trials of DRI/ACE inhibitor or DRI/ARB combinations.

FINDINGS

A total of 70 studies met the inclusion criteria for this analysis. In patients with hypertension, ACE inhibitor/ARB combinations provided limited additional reductions in blood pressure (BP) over monotherapy. Outcomes benefits were unclear: VALIANT and ONTARGET demonstrated no enhanced outcome benefit of combination therapy over monotherapy; Val-HeFT and CHARM-Added showed reduced morbidity/mortality in patients with heart failure, but at the expense of poorer tolerability. Combination therapy with the DRI aliskiren and an ACE inhibitor or ARB provided significant additional BP reductions over monotherapy in patients with mild-to-moderate hypertension, and reduced surrogate markers of organ damage in patients with heart failure or diabetic nephropathy, with generally similar safety and tolerability to the component monotherapies. No morbidity and mortality data for DRI/ACE inhibitor or DRI/ARB combinations are currently available.

CONCLUSIONS

ACE inhibitor/ARB combinations showed equivocal effects on clinical outcomes. DRI/ACE inhibitor and DRI/ARB combinations reduced markers of organ damage, but longer-term trials are required to establish whether more complete renin--angiotensin--aldosterone system control with aliskiren-based therapy translates into improved outcome benefits.

Safety and tolerability of angiotensin-converting enzyme inhibitor versus the combination of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker in patients with left ventricular dysfunction: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The addition of an angiotensin receptor blocker (ARB) to an angiotensin-converting enzyme inhibitor (ACEI) in patients with heart failure remains controversial. A recent meta-analysis showed that the combination therapy reduces hospitalization without improved survival. Whether excess risk is associated with this strategy has not been fully explored. We sought to quantify the risk of adverse events of combination therapy (ACEI+ARB) versus ACEI alone.

METHODS

MEDLINE, EMBASE, BIOSIS, and Cochrane databases were searched. Eligible studies were randomized, placebo-controlled trials of ACEI versus the combination of ACEI+ARB in patients with heart failure or left ventricular dysfunction. Included studies were reviewed to determine the frequency of adverse effects leading to discontinuation of therapy.

RESULTS

Nine trials that enrolled 18,160 patients met the inclusion criteria. A total of 9199 patients received combination therapy, and 8961 patients received an ACEI only. Patients receiving combination therapy had an increased risk of developing any adverse effect by 2.3% (relative risk [RR] = 1.27, 95% confidence interval [CI] = 1.15-1.40, P < .00001, I(2) = 15.9%, number needed to harm [NNH] = 42), hypotension by 1.1% (RR = 1.91, 95% CI = 1.37-2.66, P = .0002, I(2) = 26.6%, NNH = 89), worsening renal function by 1% (RR = 2.12, 95% CI = 1.30-3.46, P = .003, I(2) = 67.3%, NNH = 100), and hyperkalemia by 0.6% (RR = 4.17, 95% CI = 2.31-7.53, P < .00001, I(2) = 0%, NNH = 149). There was no difference in angioedema (RR = 0.88, 95% CI = 0.43-1.80, P = .72, I(2) = 0%) or cough (RR = 0.84, 95% CI = 0.65-1.09, P = .19, I(2) = 0%).

CONCLUSION

The current cumulative evidence suggests that patients with left ventricular dysfunction have an increased risk of adverse events leading to discontinuation on ACEI+ARB combination therapy compared with ACEI alone. This excess risk, coupled with a lack of consistent mortality benefit, suggests that ARBs should not routinely be added to ACEI therapy for left ventricular dysfunction. If chosen, the combination strategy may warrant closer patient monitoring to detect adverse effects.

Combination Angiotensin-Converting Enzyme Inhibitor and Angiotensin Receptor Blocker Therapy: Its Role in Clinical Practice

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers are commonly prescribed for the management of hypertension. In addition, each of these drug classes has been shown to be effective in the treatment of congestive heart failure, proteinuric chronic kidney disease, and most recently the high-cardiac-risk profile patient. The individual success of each of these drug classes has fueled the theory that given together, the overall biologic effect of both would surpass that of either given alone. The foundation of this premise, although biologically plausible, has yet to be proven in a compelling enough fashion to support the everyday use of these two drug classes in combination. Additional clarifying studies are required to establish whether specific patient subsets exist that might benefit from such combination therapy.

Combination ACE Inhibitor and Angiotensin Receptor Blocker Therapy-Future Considerations

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers are regularly prescribed for the management of hypertension. Each of these drug classes has also been shown to provide survival benefits for patients with heart failure, proteinuric chronic kidney disease, and/or a high cardiac risk profile. The individual gains seen with each of these drug classes have led to speculation that their combination might offer additive if not synergistic outcome benefits. The foundation of this hypothesis, although biologically possible, has thus far not been sufficiently well proven to support the everyday use of these 2 drug classes in combination. Additional outcomes trials, which are currently proceeding to their conclusion, may provide the necessary proof to support an expanded use of these 2 drug classes in combination.

Angiotensin II receptor blockers in congestive heart failure

The benefits of angiotensin-converting enzyme (ACE) inhibitors for the treatment of congestive heart failure (CHF) are well-established. A newer class of medications, angiotensin II receptor blockers (ARBs), may be a suitable replacement for ACE inhibitors as a result of a more complete inhibition of angiotensin II and better tolerability among patients. To examine the current literature on the efficacy and safety of ARBs in the setting of CHF, a Medline search was conducted of the English language literature for the years 1987 to 2005. Clinical trials that reported data on cardiac outcomes were reviewed. The earlier trials were direct ARB to ACE inhibitor comparisons (ELITE I and ELITE II). These studies indicated that ARBs do not confer an improvement in cardiac outcomes over ACE inhibitors. RESOLVD, Val-HeFT, and the 3 separate trials of the CHARM program investigated the addition of an ARB to standard therapy. The RESOLVD trial showed no significant differences in clinical events among ACE inhibitor, ARB, and their combination. Although no mortality benefit was evident in the Val-HeFT trial, a substantial reduction in CHF rehospitalizations was reported among patients who were not receiving ACE inhibitor therapy. The CHARM-Overall program demonstrated a significant benefit in cardiovascular death and hospital admissions for CHF with the addition of ARB to standard therapy, a benefit that was more pronounced in patients with depressed left ventricular ejection fraction. In the setting of CHF, rates of cardiac outcomes do not differ substantially between ARBs and ACE inhibitors. However, their combination may improve outcomes for patients with CHF.

Effect of quinapril or losartan alone and in combination on left ventricular systolic and diastolic functions in asymptomatic patients with diabetic autonomic neuropathy

OBJECTIVE

To investigate the effect of angiotensin converting enzyme inhibition (ACE-I) or angiotensin receptor blockade (ARB), and their combination, on both diabetic autonomic neuropathy (DAN) and left ventricular (LV) diastolic dysfunction (LVDD) in asymptomatic patients with diabetes mellitus (DM).

MATERIALS AND METHODS

Sixty-two patients (34 women) with long-term DM (24 with Type 1) and DAN, aged 51.7+/-13.9 years, free of coronary artery disease (CAD) or arterial hypertension (HT) at baseline, were studied for a 12-month period. Diagnosis of DAN was established if two or more of the standard cardiovascular reflex tests (CRT) were abnormal. Patients were randomly allocated to quinapril (20 mg/day), losartan (100 mg/day), or quinapril plus losartan (20 mg/day+100 mg/day). LV systolic and diastolic function was assessed using radionuclide ventriculography (RNV) at baseline and after 12 months of treatment.

RESULTS

In all three treatment groups, abnormal CRT values were improved. In the quinapril group, the first third filling fraction (1/3FF, 48.9+/-17.8% vs. 39.2+/-12.9% at baseline, P=.005) was increased and the atrial contribution to ventricular filling (25.1+/-6.3 vs. 30.1+/-7.8, P=.027) was reduced in the losartan group; the peak filling rate (PFR) was improved (3.41+/-.62 vs. 3.11+/-.44 volumes/s, P=.05), and in the combination group, the 1/3FF (39.4+/-11.8% vs. 29.6+/-11.9%, P=.018) was markedly increased, while the time to peak filling (TPF; 147+/-42 vs. 184+/-33 ms, P=.02) and the TPF/filling time (TPF/FT; 32.5+/-6.2% vs. 38.2+/-5.7%, P=.016) were reduced.

CONCLUSIONS

Early ACE-I or ARB improve both DAN and LVDD in asymptomatic patients with Type 1 or 2 DM, after 1 year of treatment. Their combination may be slightly better than monotherapies on DAN and LVDD. The clinical importance of these effects should be validated by larger studies.

Angiotensin Receptor Blockers in Congestive Heart Failure

Heart failure results in neurohormonal activation of which the renin-angiotensin-aldosterone system (RAS) is the main mediator. Activation of this system leads to the production of angiotensin II (ATII), which leads to multiple adverse short-term and long-term effects, including hemodynamic dysfunction, renal dysfunction, inflammation, and cardiac remodeling. Angiotensin-converting enzyme inhibitors (ACEIs) exert favorable effects in congestive heart failure (CHF) by inhibiting the production of ATII. It has been shown that ACEIs may not be able to suppress the production of ATII completely because there are RAS-independent mechanisms of ATII production. Hence, it was thought that angiotensin receptor blockers (ARBs) might be more useful in CHF because they directly block the ATII receptors. Many studies have been done to evaluate the role of ARBs in CHF. We reviewed these studies and have attempted to define the place and ARBs in the therapy for CHF.

Effects of oral fixed-dose combinations of telmisartan plus ramipril and losartan plus ramipril in hypertension: A multicenter, prospective, randomized, double-blind, phase iii trial in adult indian patients

BACKGROUND

A new oral fixed-dose combination (FDC) of telmisartan plus ramipril is being introduced in India for the treatment of patients with stage 2 hypertension.

OBJECTIVE

The aim of this study was to compare the effectiveness and tolerability of an oral FDC of telmisartan plus ramipril with those of an oral FDC of losartan plus ramipril in adult Indian patients with stage 2 hypertension.

METHODS

This multicenter, prospective, randomized, double-blind, Phase III study was conducted at 5 centers in India. Indian patients aged 18 to 65 years with uncomplicated stage 2 essential hypertension (systolic/diastolic blood pressure [SBP/DBP], >160/>100 mm Hg) were enrolled. After a 2-week placebo run-in period, patients were randomly assigned to receive telmisartan 40 mg plus ramipril 5 mg (T + R) or losartan 50 mg plus ramipril 5 mg (L + R), PO (tablet) QD (before the morning meal) for 8 weeks. Supine blood pressure (BP) was measured at 0 (baseline) and 8 weeks of treatment. The primary end point was the mean reduction from baseline in BP. Responders were classified as patients who had a DBP <90 mm Hg at the end of 8 weeks of therapy. Tolerability was assessed using spontaneous reports of adverse events (AEs) during the follow-up visits and laboratory analyses performed at week 8.

RESULTS

A total of 289 patients were enrolled (155 men, 134 women; mean age, 50.74 years). Of these, 8 patients in the T + R group and 7 in the L + R group were lost to follow-up and considered withdrawals. At the end of week 8, the mean percentage reduction in SBP was significantly greater in the T + R group compared with that in the L + R group (24.1% vs 19.4%; P < 0.05). The mean percentage reduction in DBP was also significantly greater in the T + R group compared with that in the L + R group (17.3% vs 12.5%; P < 0.05). The response rates in the T + R and L + R groups were statistically similar (79.1% vs 68.7%). The most common AEs in the T + R and L + R groups were cough (9 [6.1%] and 11 [7.8%] patients, respectively) and headache (7 [4.7%] and 8 [5.7%] patients, respectively).

CONCLUSIONS

The results in this study in Indian patients with stage 2 essential hypertension suggest that the FDC of T + R controlled BP more effectively compared with the FDC of L + R over 8 weeks. The response rates were similar between the 2 groups. Both treatments were well tolerated.

The therapeutic potential of angiotensin II receptor blockers in the treatment of heart failure

In clinical heart failure (HF) the renin-angiotensin-aldosterone system is an important component of neurohormonal activation. Angiotensin-converting enzyme inhibitors have been shown to be of great clinical benefit in reducing the production of angiotensin II. However, they do not fully suppress angiotensin II production in HF because there are other pathways through which angiotensin II can be produced. Theoretically, angiotensin II receptor blockers (ARBs) have great potential because of their ability to directly block angiotensin II produced through any pathway. A large body of literature has accumulated examining the effects of ARBs in HF. The earlier, smaller studies examined outcomes such as symptoms, neurohormonal concentrations and cardiac function. More recent, larger studies have examined the effects of ARBs on mortality and morbidity. This paper reviews the data defining the role of ARBs in the treatment of HF patients, focusing more on the large randomised clinical outcome trials.

ACE inhibitors in heart failure: what more do we need to know?

ACE inhibitors have significantly decreased cardiovascular mortality, myocardial infarction (MI), and hospitalizations for heart failure (HF) in patients with asymptomatic or symptomatic left ventricular (LV) systolic dysfunction. Furthermore, the extended 12-year study of the SOLVD (Studies Of Left Ventricular Dysfunction) Prevention and Treatment trials (X-SOLVD) demonstrated a significant benefit with a reduction of cumulative all-cause death compared with placebo (50.9% vs 56.4%) [hazard ratio (HR) 0.86; 95% CI 0.79, 0.93; p < 0.001]. The survival benefits and significant reductions in cardiovascular morbidity related to treatment with ACE inhibitors are likely achieved by titrating the dose of ACE inhibitors to the target dose achieved in clinical trials. Although the ATLAS (Assessment of Treatment with Lisinopril And Survival) study, which randomly allocated HF patients to low- or high-dose lisinopril, showed no significant difference between groups for the primary outcome of all-cause mortality (HR 0.92; 95% CI 0.82, 1.03), the predetermined secondary combined outcome of all-cause mortality and HF hospitalization was reduced by 15% for the patients receiving high-dose lisinopril compared with low-dose (p < 0.001) with a 24% reduction in HF hospitalization (p = 0.002). Despite the use of ACE inhibitors, blockade of the renin angiotensin aldosterone system (RAAS) remains incomplete, with evidence of continued production of angiotensin II by non-ACE-dependent pathways. The safety and potential benefits of angiotensin receptor antagonists (angiotensin receptor blockers [ARBs]) in patients with impaired systolic function have been assessed in moderate to large clinical trials. In patients with impaired LV systolic function and HF, combination therapy with ARBs with recommended HF therapy including ACE inhibitors in patients who remain symptomatic may be considered for its morbidity benefit. Based on the CHARM (Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity)-Added data, candesartan cilexetil in addition to standard HF therapy results in a further reduction of cardiovascular mortality. Close monitoring of renal function and serum potassium levels is needed in this setting. The VALIANT (VALsartan In Acute myocardial iNfarction Trial) results suggest that valsartan is as effective as captopril in patients following an acute MI with HF and/or LV systolic dysfunction and may be used as an alternative treatment in ACE inhibitor-intolerant patients. There was no survival benefit with valsartan-captopril combination compared with captopril alone in this trial. Despite these results, ACE inhibitors remain the first-choice therapeutic agent in post-MI patients, and ARBs can be used in patients with clear intolerance. Although the use of ACE inhibitors may be appealing in patients with HF and preserved LV systolic function, there is currently no evidence from large clinical trials to support this.

Angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers: what we know and current controversies

A little more than a decade ago, management of heart failure was changed forever when a number of randomized clinical trials confirmed that a class of drugs, angiotensin-converting enzyme (ACE) inhibitors, could improve survival in patients with heart failure. The recognition that blockade of one of the neurohumoral systems activated in heart failure could improve outcomes prompted widespread testing of other neurohumoral blockers, such as beta-adrenergic blocking agents, aldosterone antagonists, and most recently, angiotensin II type 1 receptor blockers (ARBs) for the treatment of heart failure. This article describes what is known about the use of ACE inhibitors and ARBs in the management of heart failure and presents the current controversies surrounding the use of these agents.

Angiotensin II receptor blockers in heart failure

Heart failure remains a significant cause of morbidity and mortality, despite major advances in therapy. Angiotensin II, the principal mediator of the renin-angiotensin system, exerts both short-term (e.g., hemodynamic, renal) and long-term (e.g., inflammation, cardiac remodeling) effects in the pathophysiology of cardiovascular disease. The effects of angiotensin II appear to be more completely inhibited by angiotensin II receptor blockers (ARBs), which act at the subtype 1 receptor level, than by angiotensin-converting enzyme (ACE) inhibitors because pathways other than that of ACE contribute to the generation of angiotensin II. Evidence demonstrates that ARBs, when added to conventional treatment for patients with heart failure, are associated with a reduction in morbidity and mortality as well as an improvement in quality of life. Clinical trials of ARB therapy indicate that these agents are generally well tolerated, both alone and in combination with other neurohormonal inhibitors. The current role of ARBs in heart failure is as an alternative for patients who cannot tolerate therapy with an ACE inhibitor. A number of ongoing clinical studies are likely to further define or expand the role of ARBs in the treatment of cardiovascular disease.

The role of angiotensin II receptor blockers in the treatment of heart failure patients

Evidence from large, randomized, controlled clinical trials supports the use of angiotensin-converting enzyme (ACE) inhibitors, beta blockers, and spironolactone to reduce mortality and morbidity. Despite these effective therapies, event rates related to heart failure remain high. Although ACE inhibitors reduce angiotensin II production, they do not fully suppress the increased angiotensin II production in heart failure. Angiotensin II receptor blockers (ARBs) directly block the effect of angiotensin II, derived from any source, at the receptor level and have the potential to be as effective or even more effective than ACE inhibitors. The results of a number of clinical studies have demonstrated ARBs are effective and well tolerated. However, no studies have demonstrated a convincing decrease in mortality with ARB use, although a decrease has been observed for heart failure hospitalization. The results from further studies are awaited to clarify the role of ARBs in the treatment of heart failure.

Effects of the AT1-receptor antagonist eprosartan on the progression of left ventricular dysfunction in dogs with heart failure

1. We examined the effects of eprosartan, an AT(1) receptor antagonist, on the progression of left ventricular (LV) dysfunction and remodelling in dogs with heart failure (HF) produced by intracoronary microembolizations (LV ejection fraction, EF 30 to 40%). 2. Dogs were randomized to 3 months of oral therapy with low-dose eprosartan (600 mg once daily, n=8), high-dose eprosartan (1200 mg once daily, n=8), or placebo (n=8). 3. In the placebo group, LV end-diastolic (EDV) and end-systolic (ESV) volumes increased after 3 months (68+/-7 vs 82+/-9 ml, P<0.004, 43+/-1 vs 58+/-7 ml, P<0.003, respectively), and EF decreased (37+/-1 vs 29+/-1%, P<0.001). In dogs treated with low-dose eprosartan, EF, EDV, and ESV remained unchanged over the course of therapy, whereas in dogs treated with high-dose eprosartan, EF increased (38+/-1 vs 42+/-1%, P<0.004) and ESV decreased (41+/-1 vs 37+/-1 ml, P<0.006), Eprosartan also decreased interstitial fibrosis and cardiomyocyte hypertrophy. 4. We conclude that eprosartan prevents progressive LV dysfunction and attenuates progressive LV remodelling in dogs with moderate HF and may be useful in treating patients with chronic HF.

Role of valsartan and other angiotensin receptor blocking agents in the management of cardiovascular disease

Blockade of the renin-angiotensin system by angiotensin converting enzyme (ACE) inhibitors reduces mortality and morbidity in patients post-myocardial infarction as well as in chronic heart failure and hypertension. ACE inhibitors also have a well-established place in the treatment of diabetic nephropathy. Angiotensin receptor blockers (ARBs) have been developed to produce a more complete blockade of the actions of angiotensin II as compared to other drug classes, as well as an improved side effect profile. This article provides an overview of the place of ARBs in general and of the ARB valsartan in particular, and draws comparisons to ACE inhibitors in the treatment of cardiovascular diseases.

The practical aspects of combination therapy with angiotensin receptor blockers and angiotensin-converting enzyme inhibitors

Angiotensin-converting enzyme (ACE) inhibitors and/or angiotensin receptor blockers (ARBs) are widely prescribed for the management of hypertension. ACE inhibitors (ACE-I) and, more recently, ARBs have an established track record of success in the treatment of congestive heart failure (CHF), proteinuric renal disease and most recently the hypertensive patient with a high cardiac-risk profile. The individual success of each of these drug classes has fuelled speculation that given together the overall effect of both would exceed that of either given alone. This premise, although biologically plausible, has yet to be proven in a convincing enough fashion to support the routine use of these two drug classes in combination. Additional clarifying studies are needed to establish whether specific patient subsets exist that might benefit from such combination therapy.

Angiotensin II Type 1 receptor antagonists in chronic heart failure

Angiotensin II Type 1 receptor antagonists share most but not all of their pharmacological actions with angiotensin-converting enzyme inhibitors. The latter belong to standard heart failure therapy, with proven benefit in terms of morbidity and mortality. Promising data have been provided for angiotensin II Type 1 receptor antagonists in experimental models of heart failure. In patients with hypertension and those with diabetic nephropathy, favourable results have been observed with regards to blood pressure control, reversibility of structural changes or prevention of progression of disease. The currently available clinical trials in heart failure patients with angiotensin II Type 1 receptor antagonists suggest that they may be equivalent to angiotensin-converting enzyme inhibitors, but superiority has not been proven. There is no doubt about their effectiveness with regards to symptoms; however, their effect on hospitalisation and mortality is not unequivocally demonstrated. Further trials are warranted, particularly to define their role in comparison with and in addition to angiotensin-converting enzyme inhibitors and to further characterise heart failure patient populations who derive benefit from angiotensin II Type 1 receptor blockers above and beyond angiotensin-converting enzyme inhibitors, beta-blockers and spironolactone.

Angiotensin receptor blockers in heart failure: meta-analysis of randomized controlled trials

OBJECTIVES

We sought to determine the effect of angiotensin receptor blockers (ARBs) on mortality and hospitalization in patients with heart failure (HF).

BACKGROUND

There is uncertainty regarding the efficacy of ARBs as substitute or adjunctive therapy to angiotensin-converting enzyme inhibitors (ACEIs) in the treatment of HF.

METHODS

We conducted a meta-analysis of all randomized controlled trials that compared ARBs with either placebo or ACEIs in patients with symptomatic HF. The pooled outcomes were all-cause mortality and hospitalization for HF.

RESULTS

Seventeen trials involving 12,469 patients were included. Overall, ARBs were not superior to controls in the pooled rates of death (odds ratio: 0.96; 95% confidence interval: 0.75 to 1.23) or hospitalization (0.86; 0.69 to 1.06). Stratified analysis, however, showed a non-significant trend in benefit of ARBs over placebo in reducing mortality (0.68; 0.38 to 1.22) and hospitalization (0.67; 0.29 to 1.51) when given in the absence of background ACEI therapy. When compared directly with ACEIs, ARBs were not superior in reducing either mortality (1.09; 0.92 to 1.29) or hospitalization (0.95; 0.80 to 1.13). In contrast, the combination therapy of ARBs and ACEIs was superior to ACEIs alone in reducing hospitalization (0.74; 0.64 to 0.86) but not mortality (1.04; 0.91 to 1.20).

CONCLUSIONS

This meta-analysis cannot confirm that ARBs are superior in reducing all-cause mortality or HF hospitalization in patients with symptomatic HF, particularly when compared with ACEIs. However, the use of ARBs as monotherapy in the absence of ACEIs or as combination therapy with ACEIs appears promising.

Induction of functional bradykinin b(1)-receptors in normotensive rats and mice under chronic Angiotensin-converting enzyme inhibitor treatment

BACKGROUND

The physiological effects of ACE inhibitors may act in part through a kinin-dependent mechanism. We investigated the effect of chronic ACE-inhibitor treatment on functional kinin B(1)- and B(2)-receptor expression, which are the molecular entities responsible for the biological effects of kinins.

METHODS AND RESULTS

Rats were subjected to different 6-week treatments using various mixtures of the following agents: ACE inhibitor, angiotensin AT(1)-receptor antagonist, and B(1)- and B(2)-receptor antagonists. Chronic ACE inhibition induced both renal and vascular B(1)-receptor expression, whereas B(2)-receptor expression was not modified. Furthermore, with B(1)-receptor antagonists, it was shown that B(1)-receptor induction was involved in the hypotensive effect of ACE inhibition. Using microdissection, we prepared 10 different nephron segments and found ACE-inhibitor-induced expression of functional B(1)-receptors in all segments. ACE-inhibitor-induced B(1)-receptor induction involved homologous upregulation, because it was prevented by B(1)-receptor antagonist treatment. Finally, using B(2)-receptor knockout mice, we showed that ACE-inhibitor-induced B(1)-receptor expression was B(2)-receptor independent.

CONCLUSIONS

This study provides the first evidence that chronic ACE-inhibitor administration is associated with functional vascular and renal B(1)-receptor induction, which is involved in ACE-inhibitor-induced hypotension. The observed B(1)-receptor induction in the kidney might participate in the known renoprotective effects of ACE inhibition.

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in combination: theory and practice

Angiotensin converting enzyme inhibitors and angiotensin receptor blockers are commonly used to treat hypertension and/or a range of progressive end-organ diseases. The success of each of these drug classes in disease-state management is without dispute, and has led to speculation that given together the observed response would improve upon that observed with a member of each drug class individually given. Few studies are available, however, which carefully address the effect(s) of the combination of an angiotensin-converting enzyme inhibitor and an angiotensin receptor blocker. Review of available studies would seem not to strongly support combination therapy with an angiotensin-converting enzyme inhibitor and an angiotensin receptor blocker as preferred therapy in the broad base of general hypertensive patients with or without end-organ disease. Additional clarifying studies are needed to determine if specific patient subsets exist that might benefit from such combination therapy.