Medical Therapies for Heart Failure With Preserved Ejection Fraction

Current cardiovascular pharmacotherapy targets maladaptive overactivation of the renin-angiotensin-aldosterone system (RAAS), which occurs throughout the continuum of cardiovascular disease spanning from hypertension to heart failure with reduced ejection fraction. Over the past 16 years, 4 prospective, randomized, placebo-controlled clinical trials using candesartan, perindopril, irbesartan, and spironolactone in patients with heart failure with preserved ejection fraction (HFpEF) failed to demonstrate increased efficacy of RAAS blockade added to guideline-directed medical therapy. We reappraise these trials and their weaknesses, which precluded statistically significant findings. Recently, dual-acting RAAS blockade with sacubitril-valsartan relative to stand-alone valsartan failed to improve outcome in the PARAGON-HF trial (Efficacy and Safety of LCZ696 Compared with Valsartan, on Morbidity and Mortality in Heart Failure Patients With Preserved Ejection Fraction). The majority of patients with HFpEF experience hypertension, frequently with subclinical left ventricular dysfunction, contributed to by comorbidities such as coronary disease, diabetes mellitus, overweight, and atrial fibrillation. Contrasting the findings in HFpEF, trials evaluating RAAS blockade on either side of HFpEF on the cardiovascular continuum in patients with high-risk hypertension and heart failure with reduced ejection fraction, respectively, showed positive outcomes. We do not have a biologically plausible explanation for such divergent efficacy of RAAS blockade. Based on considerations of well-established clinical efficacy in hypertension and heart failure with reduced ejection fraction and the shortcomings of aforementioned clinical trials in HFpEF, we argue that RAAS blockers including MRAs (mineralocorticoid receptor antagonists; aldosterone antagonists) should be used in the treatment of patients with HFpEF.

Heart failure with preserved ejection fraction

BACKGROUND

Approximately one half of all patients with heart failure have normal ejection fraction in the left ventricle, and heart failure is attributed to stiffness of the cardiac muscle. The most common cause is hypertension with ventricular hypertrophy.

MATERIAL AND METHOD

Literature searches were conducted in PubMed. After we made our selection, a total of 15 articles on heart failure with normal ejection fraction were included. In addition, we included nine articles from our own literature archive.

RESULTS

The diagnosis of heart failure with normal ejection fraction presupposes clinical findings consistent with heart failure and objective signs of diastolic dysfunction. The main objective sign is increased left ventricular filling pressure estimated by echocardiography. Ventricular hypertrophy and increased natriuretic peptides support the diagnosis.

INTERPRETATION

Underlying conditions and symptoms are treated, and in general the same drugs are used as for heart failure with reduced ejection fraction.

Gender differences in association between uric acid and all-cause mortality in patients with chronic heart failure

Background

Elevated serum uric acid (SUA) is associated with poor prognosis in patients with cardiovascular disease, yet it is still not decided whether the role of SUA is causal or only reflects an underlying disease. The purpose of the study was to investigate if SUA was an independent predictor of 5-year all-cause mortality in a propensity score matched cohort of chronic heart failure (HF) outpatients. Furthermore, to assess whether gender or renal function modified the effect of SUA.

Methods

Patients (n = 4684) from the Norwegian Heart Failure Registry with baseline SUA were included in the study. Individuals in the highest gender-specific SUA quartile were propensity score matched 1:1 with patients in the lowest three SUA quartiles. The propensity score matching procedure created 928 pairs of patients (73.4% males, mean age 71.4 ± 11.5 years) with comparable baseline characteristics. Kaplan Meier and Cox regression analyses were used to investigate the independent effect of SUA on all-cause mortality.

Results

SUA in the highest quartile was an independent predictor of all-cause mortality in HF outpatients (hazard ratio (HR) 1.19, 95% confidence interval (CI) 1.03–1.37, p-value 0.021). Gender was found to interact the relationship between SUA and all-cause mortality (p-value for interaction 0.007). High SUA was an independent predictor of all-cause mortality in women (HR 1.65, 95% CI 1.24–2.20, p-value 0.001), but not in men (HR 1.06, 95% CI 0.89–1.25, p-value 0.527). Renal function did not influence the relationship between SUA and all-cause mortality (p-value for interaction 0.539).

Conclusions

High SUA was independently associated with inferior 5-year survival in Norwegian HF outpatients. The finding was modified by gender and high SUA was only an independent predictor of 5-year all-cause mortality in women, not in men.

Clinical predictors of sleep apnoea in heart failure outpatients

BACKGROUND

Sleep-disordered breathing (SDB) is common in heart failure patients. Many of them still remain undiagnosed. The aim of this study was to detect clinical predictors of sleep apnoea which may help to identify patients with SDB at a heart failure clinic.

METHODS

We performed an in-home sleep study on 115 consecutive patients from our heart failure clinic. Clinical characteristics, blood samples, daytime sleepiness and quality of life were registered.

RESULTS

Among 115 patients, 52% had moderate to severe SDB. Body Mass Index (BMI) ≥ 30 kg/m² was the only independent predictor of moderate to severe SDB [Odds ratio (OR) = 3.62, 95% Confidence interval (CI) 1.40-9.36, p = 0.008]. Quality of life and level of sleepiness were not significantly associated with SDB. Patients with mild to moderate chronic obstructive pulmonary disease (COPD) were unlikely to have SDB compared with patients without COPD (OR = 0.10, 95% CI 0.02-0.43, p = 0.002). Hypertension was a predictor of having obstructive sleep apnoea (OR = 2.78, 95% CI 1.15-6.75, p = 0.02), while haemoglobin ≥ 15 g/dl was associated with central sleep apnoea (OR = 6.71, 95% CI 1.96-22.99, p = 0.002).

CONCLUSION

BMI ≥ 30 kg/m(2) is associated with moderate to severe SDB, both obstructive and central sleep apnoea. Thus, BMI may be used as one of the selection criteria for referral of heart failure patients to a sleep specialist.

Outcome of mitral valve plasty or replacement: atrial fibrillation an effect modifier

BACKGROUND

Advances in the understanding of mitral valve pathology have laid to mitral valve plasty (MPL) as the procedure of choice of all the mitral intervention as compared to mitral valve replacement (MVR).

MATERIAL AND METHODS

A cohort of 355 patients with mitral valve disease operated between January 1993 to January 2007 with closing date first of mars 2011. There were 214 MPL and 141 MVR at the Hospital discharge. This retrospective cohort had the design of exposed (MPL) versus non-exposed (MVR) with outcome total mortality and reoperation during follow up. Also echocardiography follow-up was undertaken to estimate the true long-term failure rate of repair.

RESULTS

The mean follow up was 5.3 years SE (3.82) maximum follow up was 14.1 years. Considering the patient time model the association between repair/replacement and total mortality RR = 0.43 95% (0.28-074) p = 0.002 controlling for the confounding effect of 3-vessels disease. Those results were confirmed by propensity score analysis.

CONCLUSION

In a cohort of patient with mitral valve disease undergoing MPL/MVR was examined. MPL was associated with better survival, and lower reoperation rate for patients without AF but same rate for patients with AF. We advocate more attention in controlling risk factors of AF in the clinical management of mitral disease. Long-term failure rate of MPL was low during follow up time. A replication of our results by a randomized clinical trial is mandatory.

Prognostic utility of B-type natriuretic peptides in patients with heart failure and renal dysfunction

Background

Renal dysfunction is considered a confounding variable in the interpretation of B-type natriuretic peptides (BNPs) and their amino-terminal fragments (NT-ProBNP) in patients with heart failure (HF). Our aim was to investigate the prognostic utility of BNPs and NT-proBNP in HF outpatients with renal dysfunction, and compare the prognostic significance of the corresponding BNP/NT-ProBNP levels in patients with and without renal dysfunction.

Methods

A total of 2076 patients from 13 HF clinics in the Norwegian Heart Failure Registry were investigated. The BNP/NT-ProBNP levels were categorized centre-wise into four groups using the quartile limits found in patients with preserved renal function. Patients with renal dysfunction, i.e. glomerular filtration rate (GFR) ≤60 mL/min/1.73 m², were then assigned to BNP groups 1–4 centre-wise according to their level of natriuretic peptides.

Results

Renal dysfunction was present in 37.5% of the patients, of whom the majority (59.1%) had levels of natriuretic peptide in the highest BNP group. Patients with renal dysfunction and BNP levels in the lower three BNP groups had similar 2-year survival as patients without renal dysfunction and comparable BNP levels [crude hazard ratio (HR) 1.25, 95% CI 0.82–1.89, P = 0.302, multiple adjusted HR 0.85, 95% CI 0.54–1.33, P = 0.457]. Beyond 2 years of follow-up, renal dysfunction predicted all-cause mortality irrespective of the level of natriuretic peptides at the start of follow-up.

Conclusion

In HF outpatients, the BNP/NT-ProBNP level predicted 2-year mortality irrespective of renal function and provided important prognostic information on patients with renal dysfunction.

The role of beta-blockers in the treatment of chronic heart failure

The introduction of beta-blockers in the treatment of cardiovascular diseases was a milestone and one of the most important contributions to clinical medicine in the 20th century. For many years, beta-blockers were considered contraindicated in patients with chronic heart failure owing to the negative inotropic action of these substances. With increasing evidence of neurohormonal activation in heart failure patients, there was a focus on the potential role of beta-blockers in the treatment of chronic heart failure. Several large randomized placebo- controlled clinical trials have shown favorable effects of beta-blockers on mortality and morbidity in heart failure patients with impaired systolic function. Beneficial effects in patients with preserved left ventricular systolic function are less clear. A reduction in heart rate is one of several mechanisms by which beta-blockers exert beneficial effects in chronic heart failure. In this article we present results from major clinical trials examining beta-blocker treatment in chronic heart failure patients and discuss heart rate as a therapeutic target in these patients.

Do screening blood pressure and plasma catecholamines predict development of hypertension? Twenty-year follow-up of middle-aged men

OBJECTIVES

The sympathetic nervous system is implicated in the development and maintenance of hypertension. However, the predictive impact of arterial plasma catecholamines has never been reported. We investigated arterial catecholamines and blood pressures (BPs) prospectively over 20 years in a group of well-characterized middle-aged men.

METHODS

Fifty-six of original 79 men were available for the follow-up. Multiple regression analysis was done with mean BP at follow-up as a dependent variable, and arterial plasma catecholamines and BP at baseline as independent variables.

RESULTS

Half of the originally normotensive men developed hypertension during follow-up. There were significant differences in the screening BP values measured at baseline between the new hypertensives and the sustained normotensives. Multiple regression analysis revealed arterial adrenaline at baseline as an independent predictor of mean BP at follow-up in the new hypertensives (beta = 0.646, R2 = 0.42, p = 0.007). Furthermore, arterial noradrenaline at baseline was a negative independent predictor of mean BP at follow-up in the sustained normotensives (beta = -0.578, R2 = 0.334, p = 0.020). Noradrenaline increased with age in the group as a whole (1318+/-373 vs 1534+/-505 pmol/l, p = 0.010) while adrenaline did not change.

CONCLUSION

Our data suggest that arterial adrenaline is involved in the development of hypertension over 20 years in middle-aged men. Men with sustained normotension may have an inherent protection against sympathetic overactivity. Furthermore, screening BP at baseline in normotensive men differentiated between those who developed hypertension and those who remained normotensive at follow-up.

The antioxidative effects of long-term treatment are more pronounced for carvedilol than for atenolol in post-myocardial infarction patients

Oxidative stress might exert deleterious cardiovascular effects. The aim of the present study was to compare the antioxidative effects of carvedilol and atenolol. Levels of oxidized low-density lipoprotein cholesterol (ox-LDL), vitamin E, and thiobarbituric acid reactive substances (TBARS) were measured. In a prospective, open, and end-point-blinded study, 232 patients with an acute myocardial infarction (AMI) were randomized to receive either carvedilol or atenolol at equipotent doses, and the previously mentioned 3 parameters were measured at baseline and after 12 months of active treatment, with changes during the study period being compared both within and between the groups. Ox-LDL decreased in both treatment modalities, from 40.5 +/- 15.6 to 35.0 +/- 13.8 U/L, P = 0.0001, in the carvedilol group and from 40.3 +/- 16.5 to 37.4 +/- 13.1 U/L, P = 0.044, in the atenolol group, with a significant between-group difference in the changes (P = 0.036). The levels of vitamin E did not change during carvedilol treatment (31.0 +/- 10.2 vs 31.7 +/- 11.1 micromol/L), but it decreased marginally in the atenolol group (30.8 +/- 12.1 vs 27.2 +/- 9.1 micromol/L, P = 0.056), with a significant between-group difference (P = 0.008). No significant change in TBARS was observed between the carvedilol and atenolol groups (P = 0.454). These results indicate that carvedilol has a more pronounced antioxidative effect than atenolol in post-AMI patients, which might be of clinical importance.

Arterial plasma noradrenaline predicts left ventricular mass independently of blood pressure and body build in men who develop hypertension over 20 years

BACKGROUND

Increased sympathetic activity may be an underlying mechanism in cardiovascular disease. It has been hypothesized that the degree of left ventricular (LV) hypertrophy is partly related to the blood pressure level, and partly to neurohormonal factors. The aim of this study was to investigate predictors of LV mass, including arterial plasma noradrenaline as an index of sympathetic activity, with particular emphasis on subjects who developed hypertension over a period of 20 years.

METHODS

In a 20-year prospective study of middle-aged men, sustained hypertensives (n = 22), new hypertensives (crossovers) (n = 17) and sustained normotensives (controls) (n = 17) were examined both at baseline and after 20 years of follow-up (at ages 42.1 +/- 0.5 and 62.3 +/- 0.6 years, respectively). Relationships between arterial plasma catecholamines, blood pressure and body mass index at baseline to left ventricular parameters by echocardiography at follow-up were investigated.

RESULTS

Groups were homogeneous regarding age, gender, race and body build. The group of sustained hypertensives had significantly more LV hypertrophy (P = 0.025) and diastolic dysfunction (P = 0.010). Among the crossovers, LV mass index was positively correlated to arterial plasma noradrenaline (r = 0.50, P = 0.043) and body mass index (BMI) (r = 0.51, P = 0.039) and showed a positive trend with systolic blood pressure (SBP) at baseline. Arterial plasma noradrenaline (beta = 0.47) was found to predict LV mass index after 20 years independently of BMI (beta = 0.45) and SBP (beta = 0.22) at baseline (R adjusted = 0.345, P = 0.037). Such a relationship was not found in the controls or in the sustained hypertensives, of which 16 were treated with antihypertensive drugs.

CONCLUSIONS

Arterial plasma noradrenaline at baseline, as an index of sympathetic activity, predicts LV mass at follow-up independently of systolic blood pressure and body build in middle-aged men who developed hypertension over a period of 20 years.

The angiotensin receptor antagonist valsartan: a review of the literature with a focus on clinical trials

Valsartan is an angiotensin receptor antagonist that specifically blocks the angiotensin II type 1 receptors. It is an effective and well-tolerated once-daily antihypertensive agent, with a tolerability profile similar to placebo. A recent series of large-scale clinical trials have shown the benefits of valsartan in disease states beyond hypertension. Based on the results of the Val-HeFT (Valsartan in Heart Failure Trial) and VALIANT (Valsartan in Acute Myocardial Infarction Trial) studies, valsartan is indicated for use in patients with heart failure and in patients post-myocardial infarction. Recently, in the VALUE (Valsartan Antihypertensive Long-term Use Evaluation) trial, valsartan was no more cardioprotective than calcium channel blockers, but was shown to reduce the risk of developing new-onset diabetes in hypertensive patients at high risk of cardiac events compared with calcium antagonist treatment. In diabetic patients with microalbuminuria, valsartan has been shown to have benefits beyond those attributable to blood pressure lowering alone.

Treatment of hypertension in patients with congestive cardiac failure

Hypertension is a major risk factor for the development of cardiac failure. Patients with severe heart failure and left ventricular ejection fraction <40% are excluded from the majority of hypertension trials. The European Guidelines recommend treatment of hypertension in patients with heart failure and the introduction of blood pressure-lowering drugs that deal with the underlying disease. Several of the drugs may be needed in combination to achieve target blood pressure.

Hemodynamic and neuroendocrine effects for candoxatril and frusemide in mild stable chronic heart failure

OBJECTIVES

The study aimed to assess the hemodynamic and neuroendocrine effects of candoxatril and frusemide compared with placebo in patients with mild chronic heart failure.

BACKGROUND

Candoxatril is an atriopeptidase inhibitor. It increases circulating levels of atrial natriuretic peptide leading to natriuresis and diuresis, which alleviate the symptoms of a failing heart.

METHODS

This was a multicenter, randomized, double-blind study. Forty-seven patients with mild stable chronic heart failure received candoxatril 400 mg/day, frusemide 40 mg/day or placebo for up to six weeks. Cardiac indices were determined at rest and during exercise, and blood samples were taken for laboratory analysis. Assessments were performed at baseline (day 0) and after six weeks (day 42).

RESULTS

In comparison with placebo, both drugs significantly reduced mean pulmonary capillary wedge pressure following the first dose administration. Only candoxatril significantly reduced pulmonary capillary wedge pressure during exercise on day 0, while both drugs significantly reduced this parameter on day 42. Changes in the remaining hemodynamic parameters were comparable for both drugs relative to placebo. Frusemide significantly increased mean plasma renin activity (days 0 and 42), and the mean aldosterone concentration (day 42) in comparison with placebo, whereas candoxatril caused no significant changes in any of the hormonal parameters assessed.

CONCLUSIONS

These results show that candoxatril, 400 mg/day, has a similar hemodynamic profile to frusemide, 40 mg/day, but it does not induce adverse neuroendocrine effects. Candoxatril therefore appears to offer a clinically significant advantage over frusemide, providing an alternative therapeutic approach to the treatment of patients with mild stable chronic heart failure.

[Calcium channel blockers in heart failure]

Patients with heart failure are particularly susceptible to the negative effects of calcium channel blockers because the failing heart demonstrates a defect in the delivery of calcium to the contractile proteins, and an attenuation of the normal sympathetic reflexes. Currently these drugs have no place in the treatment of heart failure caused by systolic dysfunction of the left ventricle. Calcium channel blockers should probably not be described for patients with coronary artery disease and left ventricular dysfunction. When the patient needs additional treatment for angina and beta-blockers or nitrates have not given satisfactory results, it may be appropriate to prescribe amlodipine or felodipine.

[Secondary prevention in coronary disease. A questionnaire study in Norwegian departments of internal medicine with emphasis on non-pharmacological intervention]

Research has shown that lifestyle intervention has a promising effect in patients with coronary heart disease, but little is known about the practice of such intervention. To explore this issue a questionnaire was sent to all departments of internal medicine in Norway (N = 67). 58 hospitals responded. The results showed that most hospitals offered physical training (49 hospitals) and dietary intervention programmes (51 hospitals) to patients with coronary heart disease, but only six hospitals offered a smoking cessation programme. The hospitals expressed a desire to expand the existing programmes (especially dietary intervention) and establish new ones (in particular smoking cessation), but claimed that lack of personnel and funds limited their activity. Only a few hospitals record in the medical journal that a patient has been informed about the significance of changes in lifestyle.

[Effect of 1-alpha blockader on maximal oxygen consumption and physical endurance in hypertensive men]

The effect of alpha 1 adrenoceptor blockade (doxazosin, 4 mg daily) on maximal oxygen uptake (VO2 max) and physical endurance capacity in 16 mildly hypertensive, athletic men was investigated in a randomized, placebo-controlled, double-blind, two-period of 4 weeks, cross-over study. The maximal work load obtained during graded bicycle ergometer exercise and the VO2 max were reduced by 16 +/- 3 W (mean +/- SE) and 3 +/- 1 ml x kg-1 x min-1 on doxazosin (p < 0.001 for both), and the running time on 5000 m track increased by 43 +/- 12 sec (p < 0.05). Thus, alpha 1-blockade moderately reduces VO2 max and physical endurance capacity in mildly hypertensive athletic men. However, lower systolic blood pressure (9 +/- 4 mm Hg, p < 0.05) immediately after running, and unchanged heart rate suggest a safer performance of exercise.

[Calcium antagonists in the treatment of hypertension and heart failure. A comment to recently published results of clinical trials]

Several studies have been published recently on the effect of calcium-antagonists in the treatment of hypertension and heart failure. Except for an American case-control study, in which negative results may have been caused by selection bias, other studies show that calcium-antagonists have a positive effect. They appear to reduce cardiovascular complications, lower mortality and slow down the progression of atherosclerosis. However, large trials of adequate design and force are in progress (STOP II, NORDIL, HOT, INSIGHT, ALLHAT). It is hoped that the results of these trials will clarify whether calcium-antagonist are warranted in the treatment of hypertension and associated cardiovascular disease.

[How to combine antihypertensive drugs?]

Many hypertensive patients do not respond adequately to single-drug therapy and may therefore require two or more drugs to reach the treatment goal. The drugs used in combination therapy should have additive or synergistic effects on blood pressure. A potential benefit of combinations is to use lower doses of each drug, which may attenuate or abolish the occurrence of side effects. Different combinations are discussed, as well as the inhibition of compensatory mechanisms that may otherwise counteract the antihypertensive effect.

Effect of dietary counselling on blood pressure and arterial plasma catecholamines in primary hypertension

There is still a need of support for nonpharmacologic treatment of uncomplicated, mild-to-moderate essential hypertension. We investigated whether a low sodium-based diet implemented by a nutritionist could lower blood pressure and affect sympathetic activity. Middle-aged, otherwise healthy men with never-treated essential hypertension (n = 95) were randomized to an intervention group, a blood pressure control group, and a time control group. The intervention group was advised to use less sodium chloride in their diet, and if necessary, less saturated fat and decrease body weight. They attended regular clinic visits as did the blood pressure control group. After 1 year, the intervention group had achieved on average 72 mmol/24 h lower urinary sodium excretion (P < .001) and a decrease in body weight of 2.7 +/- 0.5 kg (P < .001). Both supine and standing mean blood pressure were on average 8 to 10 mm Hg lower after intervention compared with the two control groups (P < .001). Arterial plasma epinephrine, measured in all 40-year-old subjects (n = 30), decreased in parallel in all three groups (P < .05), indicating some habituation to the invasive procedure and clinic visits. However, the decrease in norepinephrine was significant (P < .001) only in the intervention group; it correlated with the weight loss (r = 0.76, P < .05) and was significantly higher (P < .05) than in both control groups. These results suggest that broad dietary advice (ie, low intake of sodium chloride, saturated fat and energy), implemented by a nutritionist, may have a significant blood pressure lowering effect and a favorable sympathicolytic effect in uncomplicated, mild-to-moderate essential hypertension.

[Refractory hypertension]

Resistant hypertension is a common disorder in general practice, and poses a challenge to clinicians. It is generally defined as failure to reduce blood pressure adequately despite the use of at least three different antihypertensive agents with different modes of action. The importance of recognizing expansion of plasma volume as a mediator of resistance to therapy is emphasized. Some patients may have white-coat hypertension. An even larger group of patients may fail to comply with the prescribed medication. A good physician-patient relationship is vital, and education of the patient is crucial for obtaining better adherence to the medication.

Effect of alpha 1-adrenoceptor blockade on maximal VO2 and endurance capacity in well-trained athletic hypertensive men

The effect of alpha 1-adrenoceptor blockade (doxazosin, 4 mg daily) on maximal VO2 and physical endurance capacity in 16 mildly hypertensive, athletic men was investigated in a randomized, placebo-controlled, double-blind, two-period of 4 weeks, cross-over study. The maximal workload obtained during graded bicycle ergometer exercise and the corresponding maximal VO2 were reduced by 16 +/- 3 W (mean +/- SE), (P = .00003) and 3 +/- 1 mL/(kg.min) (P = .0004), respectively, on doxazosin compared with placebo. The running time on a 5000 m track increased by 43 +/- 12 sec on doxazosin (P = .04). Heart rate was unchanged during the running session. Systolic blood pressure was reduced by 9 +/- 4.1 mm Hg (P = .04) immediately after finishing 5000 m. Six subjects reported side effects from doxazosin (headache, fatigue, and leg pain). Thus, antihypertensive treatment with alpha 1-selective adrenoceptor blockade moderately, but significantly, reduces maximal O2 consumption and high intensity physical endurance capacity in mildly hypertensive athletic men. Significantly reduced systolic blood pressure and unchanged heart rate immediately after running, combined with unchanged heart rate during the race may, however, suggest a safer exercise performance.