Treatment of stable angina pectoris by ivabradine in every day practice: the REDUCTION study

Ivabradine and metoprolol in fixed dose combination: When, why and how to use it

Heart rate is an important factor in coronary artery disease and its manifestations, and as such has been considered as a possible target for therapy. Although in epidemiological, and in less degree, in clinical studies derived indications of a possible pathogenetic role of heart rate in major cardiac diseases, clinical trials did not provided any strong evidence. However, even as a simple risk marker, remains important in the treatment of coronary artery disease and heart failure. Beta-blockers are the drugs most frequently used for heart rate control. However, recent studies constantly find insufficient effectiveness of beta-blockers in heart rate control and go further to question their efficacy on outcomes, making clear the need for an additional therapy. Ivabradine, a pure heart rate inhibitor, added to classic beta-blocker treatment represent the new therapeutic option in stable coronary disease and heart failure.

Stable Angina Medical Therapy Management Guidelines: A Critical Review of Guidelines from the European Society of Cardiology and National Institute for Health and Care Excellence

Most patients with stable angina can be managed with lifestyle changes, especially smoking cessation and regular exercise, along with taking antianginal drugs. Randomised controlled trials show that antianginal drugs are equally effective and none of them reduced mortality or the risk of MI, yet guidelines prefer the use of beta-blockers and calcium channel blockers as a first-line treatment. The European Society of Cardiology guidelines for the management of stable coronary artery disease provide classes of recommendation with levels of evidence that are well defined. The National Institute for Health and Care Excellence (NICE) guidelines for the management of stable angina provide guidelines based on cost and effectiveness using the terms first-line and second-line therapy. Both guidelines recommend using low-dose aspirin and statins as disease-modifying agents. The aim of this article is to critically appraise the guidelines’ pharmacological recommendations for managing patients with stable angina.

Role of ivabradine in management of stable angina in patients with different clinical profiles

In chronic stable angina, elevated heart rate contributes to the development of symptoms and signs of myocardial ischaemia by increasing myocardial oxygen demand and reducing diastolic perfusion time. Accordingly, heart rate reduction is a well-known strategy for improving both symptoms of myocardial ischaemia and quality of life (QOL). The heart rate-reducing agent ivabradine, a direct and selective inhibitor of the I_f current, decreases myocardial oxygen consumption while increasing diastolic time, without affecting myocardial contractility or coronary vasomotor tone. Ivabradine is indicated for treatment of stable angina and chronic heart failure (HF). This review examines available evidence regarding the efficacy and safety of ivabradine in stable angina, when used as monotherapy or in combination with beta-blockers, in particular angina subgroups and in patients with stable angina with left ventricular systolic dysfunction (LVSD) or HF. Trials involving more than 45 000 patients receiving treatment with ivabradine have shown that this agent has antianginal and anti-ischaemic effects, regardless of age, sex, severity of angina, revascularisation status or comorbidities. This heart rate-lowering agent might also improve prognosis, reduce hospitalisation rates and improve QOL in angina patients with chronic HF and LVSD.

Treatment of Stable Angina with a New Fixed-Dose Combination of Ivabradine and Metoprolol: Effectiveness and Tolerability in Routine Clinical Practice

Introduction

In this prospective, multicenter, observational cohort study, the effectiveness and tolerability of the first fixed-dose combination (FDC) formulation of the selective heart rate reducing agent ivabradine and the beta-blocker metoprolol was evaluated in stable angina pectoris (AP) patients in a clinical practice setting.

Methods

Stable AP outpatients received a FDC of ivabradine and metoprolol (b.i.d.) for 4 months, in addition to cardiovascular standard therapy. Resting heart rate (HR), number of angina attacks, short-acting nitrate consumption, severity of symptoms (assessed by patient judgment and documented by CCS score) and tolerability were documented. Medication adherence was assessed by a modified four-item Morisky questionnaire. Descriptive statistics were performed on all data.

Results

A total of 747 stable AP patients (mean age, 66.4 years, 62% male, 50% and 31% with previous PCI and myocardial infarction, respectively) were included. Apart from ivabradine and beta-blockers as free combination, most frequently used concomitant standard medications at baseline were aspirin (68%), statins (71%), ACEI/AT1-blockers (76%), diuretics (35%), and calcium antagonists (15%). Highly prevalent comorbidities were hypertension (86%), hyperlipidemia (65%), and diabetes (35%). After 4 months, switch to treatment with the FDC was associated with a significant reduction in mean HR by 10 bpm. Proportion of patients with ≥ 1 angina attacks/week decreased from 38 to 7%. Patients in CCS class 1 increased (25 to 63%), while they decreased in CCS class 3 (19 to 5%). Medication adherence was also significantly improved (p < 0.001 for all changes from baseline). Mostly mild adverse events were documented in 5.4% of patients.

Conclusions

In these stable AP patients in a real-life setting, treatment with a FDC of ivabradine and metoprolol was associated with reduced HR and angina symptoms, while exercise capacity (CCS score) was improved. These effects may be mainly mediated by the increased medication adherence of patients observed with use of the FDC formulation.

Funding

Servier

Trial registration number

ISRCTN51906157

The risk of cardiovascular side effects with anti-anginal drugs

INTRODUCTION

Angina pectoris is a common presenting symptom of underlying coronary artery disease or reduced coronary flow reserve. Patients with angina have impaired quality of life; and need to be treated optimally with antianginal drugs to control symptoms and improve exercise performance. A wide range of antianginal medications are approved for the treatment of angina, and often more than one class of antianginal drugs are used to adequately control the symptoms. This expert opinion highlights the likely cardiac adverse effects of available antianginal drugs, and how to minimize these in individual patients and especially during combination treatment. Areas covered: All approved antianginal drugs, including the older and newly approved medications with different mechanism of action to the older drugs as well as some of the unapproved herbal medications. The safety profiles and potential cardiac side effects of these medications when used as monotherapy or as combination therapy are discussed and highlighted. Expert opinion: Because of the different cardiac safety profiles and possible side effects, we recommend selection of initial drug or adjustment of therapy based on the resting heart rate; blood pressure, hemodynamic status; and resting left ventricular function, concomitant medications and any associated comorbidities.

Effectiveness and Tolerability of Ivabradine with or Without Concomitant Beta-Blocker Therapy in Patients with Chronic Stable Angina in Routine Clinical Practice

Introduction

In the prospective, open-label, non-interventional, multicenter RESPONSI_fVE study, the effectiveness, response rates and tolerability of ivabradine with or without beta blocker (BB) were evaluated in patients with chronic stable angina pectoris (AP) in daily clinical practice.

Methods

In patients with AP, ivabradine was given twice daily in flexible doses for 4 months. Resting heart rate (HR), number of angina attacks, short-acting nitrate use, severity of symptoms [by Canadian Cardiovascular Society (CCS) score] and tolerability with or without existing BB therapy were documented and analyzed using descriptive statistical methods.

Results

In total, 1250 patients with AP (mean age 66.0 ± 10.9 years, 59.6% male, 31.9% previous myocardial infarction) and an indication for ivabradine were included. Sixty-five percent of all patients received BB. Further concomitant standard medication included aspirin (74.2%), statins (69.3%), angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (84.2%), diuretics (40.0%), long-acting nitrates (15.7%), and calcium antagonists (21.4%). After 4 months of ivabradine treatment (mean daily dose 11.0 ± 2.7 mg), mean HR was reduced from 82.4 ± 11.8 beats per minute (bpm) to 67.1 ± 8.4 bpm. The average number of angina attacks/week decreased from 1.2 ± 1.9 to 0.1 ± 0.6 and the average use of short-acting nitrates/week from 1.5 ± 2.8 units to 0.2 ± 1.0 units. CCS classification of patients improved from 76% classified in CCS grades II or III and 24% in CCS grade I to 66% classified in CCS grade I and only 35% remaining in CCS grades II or III at study end. Response rate to ivabradine (defined as HR <70 bpm or HR reduction ≥10 bpm) reached 87%. HR reduction, symptomatic improvement and response rates were comparable in patients with or without BB. Adverse drug reactions were reported for 2.2% of patients.

Conclusion

In this prospective study over a four-month period in clinical practice, ivabradine effectively reduced HR, angina attacks, and nitrate consumption in patients with AP with or without concomitant BB therapy. Ivabradine improved CCS scores and achieved a high treatment response rate with good general tolerability.

Funding

Servier.

Trial registration

Controlled-trials.com identifier, ISRCTN73861224.

Effectiveness of Ivabradine Treatment in Different Subpopulations with Stable Angina in Clinical Practice: A Pooled Analysis of Observational Studies

Objectives: The efficacy of ivabradine has been demonstrated in different subpopulations of stable angina patients in randomized clinical trials. This study explored its effectiveness in subpopulations seen in clinical practice as they often differ from those of randomized trials. Methods: Data were pooled from three German observational studies with similar inclusion criteria (stable angina and heart rate ≥60 bpm). All patients received 2.5, 5, or 7.5 mg b.i.d. of ivabradine for 4 months, with or without concomitant beta-blocker. Antianginal effectiveness was analyzed in subpopulations defined by gender, age, heart rate, angina severity, use of concomitant beta-blocker, previous percutaneous coronary intervention procedure, and comorbidities (including previous myocardial infarction and diabetes). Results: Treatment data were available on 8,555 patients, where therapy with ivabradine was associated with a significant reduction in the frequency of angina attacks and consumption of short-acting nitrates of 87%. Effectiveness was maintained in all investigated subpopulations, with a reduction in antianginal parameters of 82-90%. Clinical status (Canadian Cardiovascular Society class) and quality of life were also improved. Ivabradine was well tolerated in all subgroups. Conclusions: Ivabradine is effective and safe in all subpopulations of angina patients seen in clinical practice, independent of age, comorbidities, and use of beta-blocker.

Ranolazine and Ivabradine: two different modalities to act against ischemic heart disease

Among the innovative drugs recently introduced for the management of chronic stable angina, Ranolazine and ivabradine represent two most true innovations. In fact, even if both drugs act by reducing myocardial work and thus oxygen consumption, this happens by a peculiar mechanism unlike that of conventional antischemic drugs. Ranolazine mediates its antianginal effects by the inhibition of cardiac late sodium current. This improves myocardial relaxation favoring myocardial perfusion. Ivabradine is a selective If channel blocker and acts by reducing firing rate of pacemaker cells in the sinoatrial node, without affecting the duration of action potential. The reduction of heart rate causes a reduction of left ventricular end diastolic pressure and increases the time useful to coronary flow by a prolongation of the diastole. A body of evidence found that two drugs are useful in ischemic patients whether at rest or during exercise. In addition, they can be used in monotherapy or in association with other conventional anti-ischemic drugs. The two medications could be used with advantage also in microvascular angina when standard therapy is ineffective. Thus, the two drugs represent an adjunctive and powerful therapeutic modality for the treatment of chronic stable angina, especially when conventional antianginal drugs were insufficient or inadequate.

Angina treatments and prevention of cardiac events: an appraisal of the evidence

Angina pectoris is the symptomatic manifestation of transient myocardial ischaemia. At the most fundamental level, angina arises when myocardial oxygen demand exceeds the ability of the coronary circulation to provide adequate oxygen delivery to maintain normal myocardial metabolic function. In vivo, the balance of oxygen demand and delivery is a complex physiological process that can be altered by a variety of interventions. Lifestyle modification is a cornerstone of cardiovascular disease management, with or without angina. Additional pharmaceutical and physical interventions are usually applied to patients with angina. Mechanisms of action for these interventions include heart rate modulation, vascular smooth muscle relaxation, metabolic manipulation, revascularization, and others. A number of these interventions have overlapping mechanisms that target angina. Additionally, some interventions may directly or indirectly prevent or delay adverse outcomes such as myocardial infarction or death. This review summarizes current evidence for many applied ischaemia treatments documented to modify angina and comments on available evidence relating to improvement in cardiovascular outcomes.

Ivabradine, coronary artery disease, and heart failure: beyond rhythm control

Elevated heart rate could negatively influence cardiovascular risk in the general population. It can induce and promote the atherosclerotic process by means of several mechanisms involving endothelial shear stress and biochemical activities. Furthermore, elevated heart rate can directly increase heart ischemic conditions because of its skill in unbalancing demand/supply of oxygen and decreasing the diastolic period. Thus, many pharmacological treatments have been proposed in order to reduce heart rate and ameliorate the cardiovascular risk profile of individuals, especially those suffering from coronary artery diseases (CAD) and chronic heart failure (CHF). Ivabradine is the first pure heart rate reductive drug approved and currently used in humans, created in order to selectively reduce sinus node function and to overcome the many side effects of similar pharmacological tools (ie, β-blockers or calcium channel antagonists). The aim of our review is to evaluate the role and the safety of this molecule on CAD and CHF therapeutic strategies.

Selective and specific inhibition of If with ivabradine for the treatment of coronary artery disease or heart failure

Heart rate is an important contributor in the pathophysiology of both coronary artery disease (CAD) and heart failure (HF). Ivabradine is an anti-anginal and anti-ischaemic agent, which selectively and specifically inhibits the I_f current in the sino-atrial node and provides pure heart rate reduction without altering other cardiac parameters, including conduction, and without directly affecting other haemodynamic parameters. It is approved for the treatment of CAD and HF. This article summarises the pharmacological properties, pharmacokinetics, clinical efficacy and tolerability of ivabradine in the treatment of CAD and HF, and presents evidence demonstrating that the pharmacological and clinical properties and clinical efficacy of ivabradine make it an important therapeutic choice for patients with stable CAD or HF. The positive effect of ivabradine on angina pectoris symptoms and its ability to reduce myocardial ischemia make it an important agent in the management of patients with stable CAD or chronic HF. Further studies are underway to add to the already robust evidence of ivabradine for the prevention of cardiovascular events in patients with CAD but without clinical HF. The SIGNIFY (Study assessInG the morbidity–mortality beNefits of the I_f inhibitor ivabradine in patients with coronarY artery disease) trial includes patients with stable CAD and an LVEF above 40 %, with no clinical sign of HF, and is investigating the long-term effects (over a period of 48 months) of ivabradine in a large study population. So far, this study has included more than 19,000 patients from 51 countries.

Recurrent angina after coronary angioplasty: mechanisms, diagnostic and therapeutic options

Recurrent angina in patients who underwent percutaneous coronary intervention is defined as recurrence of chest pain or chest discomfort. Careful assessment is recommended to differentiate between non-cardiac and cardiac causes. In the case of the latter, recurrent angina occurrence can be related to structural ('stretch pain', in-stent restenosis, in-stent thrombosis, incomplete revascularization, progression of coronary atherosclerosis) or functional (coronary micro-vascular dysfunction, epicardial coronary spasm) causes. Even though a complete diagnostic algorithm has not been validated, ECG exercise testing, stress imaging and invasive assessment of coronary blood flow and coronary vaso-motion (i.e. coronary flow reserve, provocation testing for coronary spasm) may be required. When repeated coronary revascularization is not indicated, therapeutic approaches should aim at targeting the underlying mechanism for the patient's symptoms using a variety of drugs currently available such as beta-blockers, calcium-channel blockers, ivabradine or ranolazine.

HCN channels and heart rate

Hyperpolarization and Cyclic Nucleotide (HCN) -gated channels represent the molecular correlates of the "funny" pacemaker current (I(f)), a current activated by hyperpolarization and considered able to influence the sinus node function in generating cardiac impulses. HCN channels are a family of six transmembrane domain, single pore-loop, hyperpolarization activated, non-selective cation channels. This channel family comprises four members: HCN1-4, but there is a general agreement to consider HCN4 as the main isoform able to control heart rate. This review aims to summarize advanced insights into the structure, function and cellular regulation of HCN channels in order to better understand the role of such channels in regulating heart rate and heart function in normal and pathological conditions. Therefore, we evaluated the possible therapeutic application of the selective HCN channels blockers in heart rate control.

Ivabradine in combination with beta-blocker improves symptoms and quality of life in patients with stable angina pectoris: results from the ADDITIONS study

AIM

Several clinical trials have demonstrated the antianginal and anti-ischemic efficacy of ivabradine in combination with beta-blocker in patients with stable angina pectoris. The ADDITIONS (PrActical Daily efficacy anD safety of Procoralan(®) In combinaTION with betablockerS) study evaluated the efficacy, safety, and tolerability of ivabradine added to beta-blocker, and its effect on angina symptoms and quality of life in routine clinical practice.

METHODS

This non-interventional, multicenter, prospective study included 2,330 patients with stable angina pectoris treated with a flexible dose of ivabradine twice daily in addition to beta-blocker for 4 months. The parameters recorded included heart rate, number of angina attacks, nitrate consumption, tolerance, and quality of life.

RESULTS

After 4 months ivabradine (mean dose 12.37 ± 2.95 mg/day) reduced heart rate by 19.4 ± 11.4 to 65.6 ± 8.2 bpm (p < 0.0001). The number of angina attacks was reduced by 1.4 ± 1.9 per week (p < 0.0001), and nitrate consumption by 1.9 ± 2.9 U per week (p < 0.0001). At baseline (i.e., on beta-blocker), half of the patients (51%) were classified as Canadian Cardiovascular Society (CCS) grade II; 29% were CCS grade I. After 4 months' treatment with ivabradine, most of the patients were CCS grade I (68%). The EQ-5D index improved by 0.17 ± 0.23 (p < 0.0001). The overall efficacy of ivabradine was considered by the physicians as "very good" (61%) or "good" (36%) in most patients. Suspected adverse drug reactions were documented in 14 patients; none were severe.

CONCLUSION

In daily clinical practice, combining ivabradine with beta-blocker not only reduces heart rate, number of angina attacks, and nitrate consumption, but also improves the quality of life in patients with stable angina pectoris.

[New agents for the therapy of angina pectoris]

There is a renaissance of medical treatment of chronic angina pectoris despite of advances in interventional therapy. New drugs include nicorandil, ivabradine and ranolazine. Nicorandil dilates venous and arterial vessels via relaxation of smooth muscle cells. Since the drug has only recently been approved, the German experience is limited. Ivabradine exerts an anti-anginous effect by selective action on the sinus node with reduction of heart rate. Multiple studies have demonstrated its anti-anginal efficacy, which has also been shown if it was used as an additional therapy to classic anti-anginal treatment. Its use is reasonable as a substitute for beta-blockers or as an "add-on therapy" combined with beta-blockers, if the target heart rate for treatment of angina pectoris has not been reached. Ranolazine delays the late sodium current into the myocytes. Thereby, it improves the diastolic ventricular function and the microcirculation of the myocardium. Several large studies confirmed the anti-anginal efficacy of the drug. Currently it is used if angina pectoris still occurs under a combined treatment with different classic anti-anginal drugs.

Ivabradine: recent and potential applications in clinical practice

INTRODUCTION

published data indicate that heart rate is an independent strong predictor of cardiovascular and all-cause mortality in men and women of all ages, with and without cardiovascular disease, including atherosclerosis, ventricular arrhythmias, and left ventricular dysfunction. Ivabradine is a pure heart-rate-lowering agent with well-documented antianginal and anti-ischemic properties comparable to well-established anti-anginal agents.

AREAS COVERED

this short review explores recent results with ivabradine, a new medication that lowers heart rate by selectively inhibiting the I (f) current. This review also describes future potential applications.

EXPERT OPINION

measurement of heart rate represents an important component of the assessment of patients with coronary artery disease and chronic heart failure, and should be viewed in the same light as other risk factors, because a high heart rate has direct detrimental effects not only on myocardial ischemia but also on the progression of atherosclerosis, ventricular arrhythmias and left ventricular function. Ivabradine has anti-ischemic and antianginal efficacy equivalent to that of β-blockers and calcium channel antagonists in the treatment of chronic stable angina pectoris. Recently ivabradine has been shown to improve cardiac outcomes in stable coronary artery disease and left ventricular systolic dysfunction in patients who have heart rates of ≥ 70 bpm and in patients with stable angina.

Evaluation of aggressive heart rate reduction in patients with stable angina

BACKGROUND

There is a strong correlation between heart rate and myocardial ischemia, cardiovascular diseases, and life expectancy in general; however, heart rate has been neglected as an important risk factor as well as a therapeutic opportunity.

PURPOSE

To investigate the effect of aggressive heart rate reduction (50 ⩽ HR ⩽ 60 bpm) on anti-ischemic and anti-anginal efficacy, left ventricular function, exercise tolerance and quality of life in patients with stable coronary artery disease with or without left ventricular dysfunction during 4 months.

METHODS

A total of 159 patients presented with stable CAD without clinical heart failure symptoms were included in a open-label, non-comparative, prospective clinical study between June 2009 to February 2010 in King Abdul Aziz Specialist Hospital, Taif, KSA, Al Hayah National Hospital, Khamis Mushyt, KSA and Critical care department, Cairo University, Egypt. All included patients were, in addition to the ant ischemic treatment, subjected to aggressive heart rate control starting by beta blocker titrated to the maximum dose as tolerated, then Ivabradine added if the target heart rate is not achieved or rate control started by Ivabradine if beta blockers are contraindicated. Exercise treadmill test (ETT) to assess exercise capacity using time to 1 mm ST-segment depression in milliseconds, ejection fraction (EF) assessed by transthoracic echocardiography and frequency of angina attacks and the use of sublingual nitroglycerin per week during the last week were evaluated during a follow-up for 4 months. The patients were divided into two groups, group-I (patients achieved a resting heart rate between 50 and 60 bpm with heart rate reduction treatment) and group-II (patients with resting HR >60 bpm in spite of maximum treatment for heart rate reduction).

RESULTS

The resting heart rate was significantly reduced from 77.98 ± 8.7 at baseline to 60.68 ± 4.34 bpm after 4 months of treatment, P < 0.001. The frequency of angina pectoris attacks had been significantly reduced from 2.14 ± 1.27 to 0.48 ± 0.58 attacks per week, P < 0.001 and the highest significant reduction was observed with group-I. Also, the frequency of use sublingual nitrate therapy was significantly reduced from 1.38 ± 1.1 tablet per week at the last week before the study to 0.12 ± 0.33 tablet per week during the last week after 4 months of treatment, P < 0.001 and the reduction was more significantly with group-I. Exercise treadmill test demonstrated statistically significant increase in the time to 1 mm ST-segment depression from 357.36 ± 66.73 at baseline to 387.96 ± 65.19 ms. after 4 months with P < 0.001. The degree of improvement was significantly higher for group-I (from 358.06 ± 68.81 at baseline to 391.71 ± 69.01 after 4 months with P < 0.001) than that of group-II (from 356.11 ± 64.8 at baseline to 381.27 ± 59.08 after 4 months with P < 0.001). Ejection fraction showed a statistically significant increase from 59.76 ± 6.86 at baseline to 61.04 ± 5.35 after 4 months with P < 0.001.

CONCLUSION

This study indicates that heart rate reduction has been associated with an improvement in quality of life in patients with stable coronary artery disease, presenting new opportunities for treatment.

[ProCor: an extramural screening on heart rate reduction in patients with chronic stable angina pectoris in Austria]

Based on the evidence from large clinical and epidemiological studies indicating an independent prognostic role of heart rate in cardiovascular disease, the assessment and correction of elevated heart rate is of significant prognostic relevance. In the present study conducted with the support of 74 specialists of Internal Medicine in 2009 in Austria, heart rate in patients with coronary heart disease (CHD) and chronic stable angina pectoris was evaluated in relation to pre-existing and concomitant diseases, angina-severity (CCS), angina-symptoms and treatment. For all variables, descriptive statistical analyses were performed according to three predefined groups with heart rates <60 bpm (HR-1), 60-70 bpm (HR-2), and >70 bpm (HR-3). Of the 1280 patients 21.8% had a heart rate of <60 bpm, 39.6% of 60-70 bpm, and 38.5% of >70 bpm. A significant association was shown between elevated heart rate and concomitant disease, e.g., peripheral artery disease (p = 0.046), psoriasis (p = 0.029), previous acute coronary syndrome (p = 0.001), COPD (p < 0.001), diabetes mellitus (p = 0.004), and depression (p < 0.001). CCS-severity was correlated with heart rates (mean values; CCS-0: 66.8 bpm, CCS-IV: 77.5 bpm). Angina-pectoris (AP) symptoms were more common in patients with heart rates of >70 bpm (HR-3: 1,2 AP-events/week; HR-2: 1 AP-events/week; HR-1: 0,7 AP events/week; each time p < 0.001). The majority of patients were treated with betablockers (74%); yet, the average dose was approximately half the maximal recommended dose. Despite inadequate heart rate reduction in patients on betablockers, selective heart rate lowering agents such as ivabradine were used in only 1.6% of patients. Overall, these results illustrate that heart rate as an important therapeutic target in CHD-patients with chronic stable angina is still underestimated in contemporary clinical practice.