Usefulness of amlodipine for angina pectoris

Clinical Outcomes of Calcium-Channel Blocker vs Beta-Blocker: From the Korean Acute Myocardial Infarction Registry

Background

Although current guidelines recommend beta-blockers (BBs) after acute myocardial infarction (AMI), the role of calcium-channel blockers (CCBs) has not been well investigated, especially nondihydropyridine.

Objectives

This study aimed to compare the effects of CCBs on cardiovascular outcomes compared with BBs in AMI because patients from East Asia have a higher incidence of a vasospastic angina component compared with Western countries.

Methods

Among 15,628 patients enrolled in the KAMIR-V (Korean Acute Myocardial Infarction Registry-V), we evaluated 10,650 in-hospital survivors who were treated with either CCBs or BBs. We applied a propensity score for 1:4 pair matching of baseline covariates and Cox regression to compare CCBs and BBs. The primary endpoint was all-cause death at 1 year. The secondary endpoints were 1-year major adverse cardiac and cerebrovascular events, which was the composite of cardiac death, myocardial infarction, revascularization, and readmission due to heart failure and stroke.

Results

There was a significant interaction with the treatment arm with left ventricular ejection fraction (LVEF) (P for interaction = 0.011). CCB groups at discharge had higher 1-year cardiac death and major adverse cardiac and cerebrovascular events for patients with LVEF <50% (HR: 4.950; 95% CI: 1.329-18.435; P = 0.017; and HR: 1.810; 95% CI: 1.038-3.158; P = 0.037, respectively) but not for patients with LVEF ≥50% (HR: 0.699; 95% CI: 0.435-1.124; P = 0.140).

Conclusions

CCB therapy did not increase adverse cardiovascular events for patients after AMI with preserved LVEF. CCBs can be considered as an alternative for BBs in East Asian patients after AMI with preserved LVEF.

Angina in 2022: Current Perspectives

Angina is the main symptom of ischemic heart disease; mirroring a mismatch between oxygen supply and demand. Epicardial coronary stenoses are only responsible for nearly half of the patients presenting with angina; whereas in several cases; symptoms may underlie coronary vasomotor disorders; such as microvascular dysfunction or epicardial spasm. Various medications have been proven to improve the prognosis and quality of life; representing the treatment of choice in stable angina and leaving revascularization only in particular coronary anatomies or poorly controlled symptoms despite optimal medical therapy. Antianginal medications aim to reduce the oxygen supply-demand mismatch and are generally effective in improving symptoms; quality of life; effort tolerance and time to ischemia onset and may improve prognosis in selected populations. Since antianginal medications have different mechanisms of action and side effects; their use should be tailored according to patient history and potential drug-drug interactions. Angina with non-obstructed coronary arteries patients should be phenotyped with invasive assessment and treated accordingly. Patients with refractory angina represent a higher-risk population in which some therapeutic options are available to reduce symptoms and improve quality of life; but robust data from large randomized controlled trials are still lacking.

Evaluation of the Safety and Efficacy of Dual Therapy Perindopril/Amlodipine in the Management of Hypertension. A Systematic Review and Meta-Analysis

INTRODUCTION

Hypertension represent the commonest cause of death in 2017. Hypertension is classified into two types which are primary or essential hypertension and secondary hypertension. The perindopril-amlodipine combination showed a significant effect in reduction of the elevated BP and the cardiovascular complications.

AIM

To evaluate the efficacy and safety of a fixed-dose single-pill combination of perindopril-amlodipine in hypertensive patients.

METHODS

We searched PubMed, Medline, SCOPUS, and Web of Science for relevant clinical trials. Quality appraisal was evaluated according to GRADE and we assessed the risk of bias using Cochrane's risk of bias tool. We included the following outcomes: systolic blood pressure, diastolic blood pressure, pulse pressure, mean blood pressure, heart rate, cough, dizziness, headache, and peripheral edema. We performed the analysis of homogeneous data under the fixed-effects model, while analysis of heterogeneous data was analyzed under the random-effects model. We conducted a meta-regression according to the dose.

RESULTS

We included ten clinical trials. The pooled analysis showed that there was a significant reduction of the systolic blood pressure, diastolic blood pressure, pulse plessure, mean blood pressure, and heart rate after the the perindopril-amlodipine combination (MD = 18.96 [14.32, 23.60], P < 0.0001), (MD = 11.90 [8.45, 15.35], P < 0.0001), (MD = 8.44 [6.91, 9.97], P = 0.0001), (MD = 13.07 [5.86, 20.29], P = 0.0004), and (MD = 2.93 [0.89, 4.96], P = 0.005), respectively. The results of the meta-regression revealed that the efficacy is increased by increasing the dose (P < 0.001) CONCLUSION: The use of the perindopril-amlodipine combination had a significant effect on the reduction of SBP, DBP, mean blood pressure, pulse pressure, and HR.

Advancements in pharmacotherapy for angina

INTRODUCTION

Angina pectoris is the most prevalent symptomatic manifestation of ischemic heart disease, frequently leads to a poor quality of life, and is a major cause of medical resource consumption. Since the early descriptions of nitrite and nitrate in the 19th century, there has been considerable advancement in the pharmacologic management of angina. Areas covered: Management of chronic angina is often challenging for clinicians. Despite introduction of several pharmacological agents in last few decades, a significant proportion of patients continue to experience symptoms (i.e., refractory angina) with subsequent disability. For the purpose of this review, we searched PubMed and Cochrane databases from inception to August 2016 for the most clinically relevant publications that guide current practice in angina therapy and its development. In this article, we briefly review the pathophysiology of angina and mechanism-based classification of current therapy. This is followed by evidence-based insight into the traditional and novel pharmacotherapeutic agents, highlighting their clinical usefulness. Expert opinion: Considering the wide array of available therapies with different mechanism efficacy and limiting factors, a personalized approach is essential, particularly for patients with refractory angina. Ongoing research with novel pharmacologic modalities is likely to provide new options for management of angina.

Amlodipine in hypertension: a first-line agent with efficacy for improving blood pressure and patient outcomes

OBJECTIVES

Hypertension is well established as a major risk factor for cardiovascular disease. Although there is undeniable evidence to support the beneficial effects of antihypertensive therapy on morbidity and mortality, adequate blood pressure management still remains suboptimal. Research into the treatment of hypertension has produced a multitude of drug classes with different efficacy profiles. These agents include β-blockers, diuretics, ACE inhibitors, angiotensin receptor blockers and calcium channel blockers. One of the oldest groups of antihypertensives, the calcium channel blockers are a heterogeneous group of medications.

METHODS

This review paper will focus on amlodipine, a dihydropyridine calcium channel blockers, which has been widely used for 2 decades.

RESULTS

Amlodipine has good efficacy and safety, in addition to strong evidence from large randomised controlled trials for cardiovascular event reduction.

CONCLUSIONS

Amlodipine should be considered a first-line antihypertensive agent.

Pharmacotherapy of Vasospastic Angina

Vasospastic angina is a diagnosis of exclusion that manifests with signs and symptoms, which overlap with obstructive coronary artery disease, most often ST-segment elevation myocardial infarction. The pharmacotherapy that is available to treat vasospastic angina can help ameliorate angina symptoms. However, the etiology of vasospastic angina is ill-defined, making targeted pharmacotherapy difficult. Most patients receive pharmacotherapy that includes calcium channel blockers and/or long-acting nitrates. This article reviews the efficacy and safety of the pharmacotherapy used to treat vasospastic angina. High-dose calcium channel blockers possess the most evidence, with respect to decreasing angina incidence, frequency, and duration. However, not all patients respond to calcium channel blockers. Nitrates and/or alpha1-adrenergic receptor antagonists can be used in patients who respond poorly to calcium channel blockers. Albeit, evidence for use of nitrates and alpha1-adrenergic receptor antagonists in vasospastic angina is not as robust as calcium channel blockers and can exacerbate adverse effects when added to calcium channel blocker therapy. Despite having a clear benefit in patients with obstructive coronary artery disease, the benefit of beta-adrenergic receptor antagonists, statins, and aspirin remains unclear. More data are needed to elucidate whether or not these agents are beneficial or harmful to patients being treated for vasospastic angina. Overall, the use of pharmacotherapy for the treatment of vasospastic angina should be guided by patient-specific factors, such as tolerability, adverse effects, drug–drug, and drug–disease interactions.

Post-valvular surgery multi-vessel coronary artery spasm - A literature review

Coronary artery spasm (CAS) refers to the spontaneous or stimuli-induced transient, often localized and intense subtotal or total constriction/occlusion of the epicardial coronary artery, usually concomitant with angina pectoris with associated elevation of the ST segment on electrocardiogram (ECG). In this article, we present a literature review on post-valvular surgery CAS and report the clinical case of a 77 year-old man who experienced severe early post-aortic surgery chest pain and hemodynamic instability. Emergent coronary angiography revealed severe occlusion of multiple branches of both coronary arteries. The CAS was alleviated with intracoronary infusion of nitroglycerin.

A randomised, multicentre, double blind, placebo controlled trial to evaluate the efficacy and safety of cilostazol in patients with vasospastic angina

OBJECTIVES

We conducted a randomised, double blind, placebo controlled trial to assess the efficacy and safety of cilostazol, a selective inhibitor of phosphodiesterase 3, in patients with vasospastic angina (VSA).

BACKGROUND

Cilostazol has been shown to induce vascular dilatation, but its efficacy in patients with VSA is unknown.

METHODS

Between October 2011 and July 2012, 50 patients with confirmed VSA who had ≥1 angina episodes/week despite amlodipine therapy (5 mg/day) were randomly assigned to receive either cilostazol (up to 200 mg/day) or placebo for 4 weeks. All patients were given diaries to record the frequency and severity of chest pain (0-10 grading). The primary endpoint was the relative reduction of the weekly incidence of chest pain.

RESULTS

Baseline characteristics were similar between the two groups. Among 49 evaluable patients (25 in the cilostazol group, 24 in the placebo group), the primary endpoint was significantly greater in the cilostazol group compared with the placebo group (-66.5±88.6% vs -17.6±140.1%, respectively, p=0.009). The secondary endpoints, including a change in the frequency of chest pain (-3.7±0.5 vs -1.9±0.6, respectively, p=0.029), a change in the chest pain severity scale (-2.8±0.4 vs -1.1±0.4, respectively, p=0.003), and the proportion of chest pain-free patients (76.0% vs 33.3%, respectively, p=0.003) also significantly favoured cilostazol. Headache was the most common adverse event in both groups (40.0% vs 20.8%, respectively, p=0.217).

CONCLUSIONS

Cilostazol is an effective therapy for patients with VSA uncontrolled by conventional amlodipine therapy, and has no serious side effects.

TRIAL REGISTRATION NUMBER

NCT01444885.

Management and outcomes of non-ST elevation acute coronary syndromes in relation to previous use of antianginal therapies (from the Canadian Global Registry of Acute Coronary Events [GRACE] and Canadian Registry of Acute Coronary Events [CANRACE])

Randomized trials have established the efficacy of antianginal medications in the treatment of chronic stable coronary disease. Using data from the Global Registry of Acute Coronary Events (GRACE) and Canadian Registry of Acute Coronary Events (CANRACE), we examined the temporal trends in antianginal use (beta blockers, calcium antagonists, and nitrates) before non-ST-elevation acute coronary syndrome presentation from 1999 to 2008 in 10,019 patients. The relationships among previous antianginal use, clinical characteristics on presentation, and in-hospital management and outcomes were examined. Beta blockers were the most commonly used agents, and there was a significant decline in the use of nitrates over time. Compared with patients not on any antianginal therapy before presentation, those on treatment were more likely to be older, female, and have a history of hypertension, diabetes, previous angina, and myocardial infarction; they were less likely to present with positive biomarkers (all p <0.001). Patients not on antianginal therapy before presentation were more likely to undergo coronary angiography and percutaneous coronary intervention and less likely to have recurrent ischemia during hospitalization (all p <0.001). In multivariable analysis, previous antianginal use was independently associated with lower use of coronary angiography in hospital (p = 0.034) but not with in-hospital mortality. In conclusion, there has significant temporal decline in nitrate use before non-ST-elevation acute coronary syndrome. Patients receiving antianginal therapy before presentation more frequently had preexisting cardiovascular disease and previous revascularization and were less likely to present with non-ST-segment elevation MI compared with patients on no antianginal therapies. Previous antianginal use was independently associated with a lower use of coronary angiography in hospital.

A randomized, double-blind comparison of lercanidipine 10 and 20 mg in patients with stable effort angina: clinical evaluation of cardiac function by ambulatory ventricular scintigraphic monitoring

We evaluated the antiischemic action and the effects on left ventricular response to exercise of lercanidipine, a long-acting dihydropyridine calcium antagonist, in 23 patients with stable effort angina in a randomized, double-blind, parallel trial. Left ventricular function was assessed during upright bicycle exercise using an ambulatory radionuclide detector for continuous noninvasive monitoring of cardiac function. Exercise was performed under control conditions before (run-in placebo period) and after 2-week treatment with lercanidipine 10 or 20 mg once daily. During the placebo run-in period and at the study end, patients underwent clinical examination, ECG, exercise tests, ambulatory ventricular scintigraphic monitoring (VEST). Results showed that both drug doses increased time to onset of ST segment depression >/=1 mm and peak ST segment depression, with improvement of total exercise duration. Heart rate, blood pressure, and the rate-pressure product did not significantly change with respect to pretreatment value. The left ventricular ejection fraction, indicating contractility state of myocardium, was unchanged at rest and during exercise after both lercanidipine doses. In conclusion, lercanidipine is safe and effective in reducing ischemia in patients with stable effort angina without any deterioration of cardiac function.

Calcium channel blockers: an update

This paper reviews the current literature pertaining to calcium channel blockers, including their classification, properties, and therapeutic indications, in light of several recent trials that have addressed their safety. Calcium channel blockers are a structurally and functionally heterogeneous group of medications that are used widely to control blood pressure and manage symptoms of angina. They are classified as dihydropyridines or nondihydropyridines. As a class, they are well tolerated and are associated with few side effects. The question of whether they may precipitate cardiovascular events has been largely settled by recent trials, such as the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), the International Verapamil Slow-Release/Trandolapril Study (INVEST), and the Controlled Onset Verapamil Investigation of Cardiovascular Endpoints (CONVINCE) study, in which no such association was found. Even so, the use of these agents has been linked with an increased risk of heart failure. Thus, long-acting calcium channel blockers may be safely used in the management of hypertension and angina. However, as a class, they are not as protective as other antihypertensive agents against heart failure.

De la première à la quatrième génération de dihydropyridines : vers une meilleure efficacité et une meilleure tolérance

Dihydropyridines are among the most widely used drugs for the management of cardiovascular disease. Introduced in the 1960s, dihydropyridines have undergone several changes to optimise their efficacy and safety. Four generations of dihydropyridines are now available. The first-generation (nicardipine) agents have proven efficacy against hypertension. However, because of their short duration and rapid onset of vasodilator action, these drugs were more likely to be associated with adverse effects. The pharmaceutical industry responded to this problem by designing slow-release preparations of the short-acting drugs. These new preparations (second generation) allowed better control of the therapeutic effect and a reduction in some adverse effects. Pharmacodynamic innovation with regard to the dihydropyridines began with the third-generation agents (amlodipine, nitrendipine). These drugs exhibit more stable pharmacokinetics, are less cardioselective and, consequently, well tolerated in patients with heart failure. Highly lipophilic dihydropyridines are now available (lercanidipine, lacidipine). These fourth-generation agents provide a real degree of therapeutic comfort in terms of stable activity, a reduction in adverse effects and a broad therapeutic spectrum, especially in myocardial ischaemia and potentially in congestive heart failure.

A randomized, double-blind comparison of 10 and 20 mg lercanidipine in patients with stable effort angina: effects on myocardial ischemia and heart rate variability

We evaluated the anti-ischemic action and the effects on autonomic function of lercanidipine, a long-acting dihydropyridine calcium antagonist, in 25 patients with stable effort angina in a randomized, double-blind, parallel trial. After a 2-week placebo run-in period, patients entered a 2-week treatment period with 10 or 20 mg of lercanidipine once daily. During the placebo run-in period and at the study end, the patients underwent clinical examination, electrocardiography, exercise tests, 24-hour Holter electrocardiography for long-term heart rate variability evaluation, and short-term spectral analysis of heart rate and systolic blood pressure variability and plasma epinephrine and norepinephrine levels at rest and during tilting. Results showed that time to onset of ST segment depression > or =1 mm was significantly increased by both drug doses. No significant change was recorded in the average hourly heart rate after treatment with both 10 and 20 mg of lercanidipine. During the 24-hour recordings, no significant change was observed in low-frequency power, high-frequency power, or low frequency/high frequency. In the standing position, there was a significant increase in plasma norepinephrine and epinephrine concentration in both groups, and no change in the supine position after 10 and 20 mg of lercanidipine. When considering short-term heart rate variability, no significant difference was observed in either treatment group in low frequency, high frequency, or their ratio on electrocardiographic R-R spectra. The blood pressure spectral component was also unchanged. In conclusion, lercanidipine is effective in reducing ischemia in patients with stable effort angina. Moreover, lercanidipine does not cause adrenergic activation, which is the main mechanism hypothesized to explain the negative effect on cardiovascular mortality assigned to short-acting dihydropyridine calcium antagonists.

Clinical pharmacokinetics of vasodilators. Part I

Understanding the mechanism of action and the pharmacokinetic properties of vasodilatory drugs facilitates optimal use in clinical practice. It should be kept in mind that a drug belongs to a class but is a distinct entity, sometimes derived from a prototype to achieve a specific effect. The most common pharmacokinetic drug improvement is the development of a drug with a half-life sufficiently long to allow an adequate once-daily dosage. Developing a controlled release preparation can increase the apparent half-life of a drug. Altering the molecular structure may also increase the half-life of a prototype drug. Another desirable improvement is increasing the specificity of a drug, which may result in fewer adverse effects, or more efficacy at the target site. This is especially important for vasodilatory drugs which may be administered over decades for the treatment of hypertension, which usually does not interfere with subjective well-being. Compliance is greatly increased with once-daily dosing. Vasodilatory agents cause relaxation by either a decrease in cytoplasmic calcium, an increase in nitric oxide (NO) or by inhibiting myosin light chain kinase. They are divided into 9 classes: calcium antagonists, potassium channel openers, ACE inhibitors, angiotensin-II receptor antagonists, alpha-adrenergic and imidazole receptor antagonists, beta 1-adrenergic agonist, phosphodiesterase inhibitors, eicosanoids and NO donors. Despite chemical differences, the pharmacokinetic properties of calcium antagonists are similar. Absorption from the gastrointestinal tract is high, with all substances undergoing considerable first-pass metabolism by the liver, resulting in low bioavailability and pronounced individual variation in pharmacokinetics. Renal impairment has little effect on pharmacokinetics since renal elimination of these agents is minimal. Except for the newer drugs of the dihydropyridine type, amlodipine, felodipine, isradipine, nilvadipine, nisoldipine and nitrendipine, the half-life of calcium antagonists is short. Maintaining an effective drug concentration for the remainder of these agents requires multiple daily dosing, in some cases even with controlled release formulations. However, a coat-core preparation of nifedipine has been developed to allow once-daily administration. Adverse effects are directly correlated to the potency of the individual calcium antagonists. Treatment with the potassium channel opener minoxidil is reserved for patients with moderately severe to severe hypertension which is refractory to other treatment. Diazoxide and hydralazine are chiefly used to treat severe hypertensive emergencies, primary pulmonary and malignant hypertension and in severe preeclampsia. ACE inhibitors prevent conversion of angiotensin-I to angiotensin-II and are most effective when renin production is increased. Since ACE is identical to kininase-II, which inactivates the potent endogenous vasodilator bradykinin, ACE inhibition causes a reduction in bradykinin degradation. ACE inhibitors exert cardioprotective and cardioreparative effects by preventing and reversing cardiac fibrosis and ventricular hypertrophy in animal models. The predominant elimination pathway of most ACE inhibitors is via renal excretion. Therefore, renal impairment is associated with reduced elimination and a dosage reduction of 25 to 50% is recommended in patients with moderate to severe renal impairment. Separating angiotensin-II inhibition from bradykinin potentiation has been the goal in developing angiotensin-II receptor antagonists. The incidence of adverse effects of such an agent, losartan, is comparable to that encountered with placebo treatment, and the troublesome cough associated with ACE inhibitors is absent.

Evaluation of changes in sympathetic nerve activity and heart rate in essential hypertensive patients induced by amlodipine and nifedipine

OBJECTIVE

To compare the effects of amlodipine and nifedipine on heart rate and parameters of sympathetic nerve activity during the acute and chronic treatment periods in order to elucidate their influence on cardiovascular outcome.

DESIGN

A randomized and single-blind study.

METHODS

We performed 24 h ambulatory electrocardiography and blood pressure monitoring of 45 essential hypertensive inpatients. Plasma and urinary catecholamine levels were measured during the control (pretreatment) period, on the first day (acute period) and after 4 weeks (chronic period) of administration of amlodipine and of short-acting nifedipine or its slow-releasing formulation. The low-frequency and high-frequency power spectral densities and low-frequency: high-frequency ratio were obtained by heart rate power spectral analysis.

RESULTS

Blood pressure was significantly and similarly reduced by administrations of amlodipine, short-acting nifedipine and slow-releasing nifedipine during the chronic period. The total QRS count per 24 h, which remained constant during the chronic period of administration of slow-releasing nifedipine and was increased by administration of nifedipine, was decreased by 2.8% by administration of amlodipine. Administration of amlodipine decreased the plasma and urinary norepinephrine levels during the chronic period, whereas the levels were significantly increased by administration of short-acting nifedipine and not changed by administration of slow-release nifedipine. Although low-frequency: high-frequency ratio was increased significantly by administration of short-acting nifedipine and slightly by administration of slow-releasing nifedipine, administration of amlodipine reduced it during the acute and chronic periods.

CONCLUSIONS

Administration of amlodipine did not induce an increase in sympathetic nerve activity in essential hypertensive patients during the chronic period, suggesting that beneficial effects on essential hypertension can be expected after its long-term administration. Administration of slow-releasing nifedipine induces milder reflex sympathetic activation than does that of short-acting nifedipine.

Effect of metoprolol and amlodipine on myocardial total ischaemic burden in patients with stable angina pectoris

OBJECTIVE

A randomized double-blind cross-over study to assess the effect on myocardial total ischaemic burden and the anti-anginal efficacy of the beta-1-blocker metoprolol given as metoprolol CR/Zok versus the calcium channel blocker amlodipine, both given in the recommended and commonly used doses of 100 mg o.d. and 5 mg o.d., respectively.

METHOD

Fifty-two patients with a history of stable exercise-induced angina pectoris and at least six episodes of significant ST-segment depression during 24-h ambulatory electrocardiographic monitoring after 9 days of placebo were included in the study. The patients first completed a 9-day placebo run-in phase with additional administration of a long-acting nitrate during the first 7 days. They then received in a randomized sequence metoprolol CR/Zok and amlodipine each for 4 weeks. During placebo treatment and at the end of each phase of active treatment the patients' clinical progress was assessed and a 24-h ECG monitor performed.

RESULTS

Forty-seven patients completed the two 4-week treatment periods. Five patients withdrew from the study. The number of ischaemic episodes during 24 h was 30.4 at baseline with placebo, which was reduced significantly by both treatments (P<0.005) to 6.8 episodes after metoprolol and 15.8 episodes after amlodipine treatment (P<0.001 for the difference between the treatment groups). Metoprolol and amlodipine reduced the total duration of ischaemic episodes from 86.0 min to 15-1 and 48.3 min with a mean episode duration of 1.1 and 2.6 min, respectively. Twenty patients on metoprolol (42.6%) and four on amlodipine (8.4%) showed no ST-segment depression at the end of treatment. Baseline heart rate of 80 b.p.m. decreased by 11.1 b.p.m. after metoprolol and increased by 4b.p.m. after amlodipine. Anginal attacks were reduced from 14.8 attacks per week at baseline to 2.4 attacks on metoprolol and 4.4 attacks on amlodipine treatment. For all variables the observed changes from baseline were significant after either treatment (P<0.005) with a significantly more pronounced effect in favour of metoprolol (P<0.0001). Ten patients reported nine different adverse events during metoprolol treatment. On amlodipine, 12 patients were affected by 11 different symptoms leading to three treatment withdrawals. On metoprolol one patient withdrew due to adverse events.

CONCLUSION

Both drugs reduce total ischaemic burden by reducing ischaemic episodes and antianginal attacks, with a significantly greater effect from metoprolol 100 mg o.d. as compared to amlodipine 5 mg o.d.

Calcium channel blockers in heart failure: help or hindrance?

Since their development, calcium channel blocking agents have stimulated interest in their potential benefit for a variety of cardiovascular disorders, including heart failure. The rationale for the potential benefit of calcium channel blockers in heart failure is multi-factorial, including vasodilation, correction of perturbed diastolic relaxation, anti-ischemic action, and potential for inhibiting myocyte hypertrophy and injury. Despite these potential benefits, the degree of salutary influence has remained controversial, and a number of studies have suggested potential adverse action in patients with heart failure, perhaps linked to either negative inotropic action or to reflex neurohormonal activation. Diversity among different agents, particularly with regard to tissue selectivity and pharmacokinetics may imply substantial differences in the relative benefits and risks in various subgroups of patients with heart failure. One trial with the newer dihydropyridine agent, amlodipine, indicates benefit to survival in patients with moderate to severe heart failure and reduced ejection fraction. The reproducibility of this finding and the mechanism for this benefit deserves further investigation.

Re-examining the clinical safety and roles of calcium antagonists in cardiovascular medicine

Despite recent analyses questioning the safety of calcium antagonists, evidence and clinical practice strongly support a major role for these drugs in the management of many cardiovascular diseases such as arrhythmia, vascular spasm, hypertension, diastolic dysfunction, stable angina, and myocardial infarction. These agents are a heterogeneous class of drugs with each formulation possessing unique properties and clinical applications. This article presents a review of the available literature and discusses the recommended use of various calcium antagonists in the treatment of diseases of the heart and vascular system.

Calcium antagonists and mortality in patients with coronary artery disease: a cohort study of 11,575 patients

OBJECTIVES

This study sought to establish the risk ratio for mortality associated with calcium antagonists in a large population of patients with chronic coronary artery disease.

BACKGROUND

Recent reports have suggested that the use of short-acting nifedipine may cause an increase in overall mortality in patients with coronary artery disease and that a similar effect may be produced by other calcium antagonists, in particular those of the dihydropyridine type.

METHODS

Mortality data were obtained for 11,575 patients screened for the Bezafibrate Infarction Prevention study (5,843 with and 5,732 without calcium antagonists) after a mean follow-up period of 3.2 years.

RESULTS

There were 495 deaths (8.5%) in the calcium antagonist group compared with 410 in the control group (7.2%). The age-adjusted risk ratio for mortality was 1.08 (95% confidence interval [CI] 0.95 to 1.24). After adjustment for the differences between the groups in age and gender and the prevalence of previous myocardial infarction, angina pectoris, hypertension, New York Heart Association functional class, peripheral vascular disease, chronic obstructive pulmonary disease, diabetes and current smoking, the adjusted risk ratio declined to 0.97 (95% CI 0.84 to 1.11). After further adjustment for concomitant medication, the risk ratio was estimated at 0.94 (95% CI 0.82 to 1.08).

CONCLUSIONS

The current analysis does not support the claim that calcium antagonist therapy in patients with chronic coronary artery disease, whether myocardial infarction survivors or others harbors an increased risk of mortality.

Sex- and age-related antihypertensive effects of amlodipine. The Amlodipine Cardiovascular Community Trial Study Group

This community-based study assessed whether there were age, sex, or racial differences in response to amlodipine 5 to 10 mg once daily in patients with mild to moderate essential hypertension. This prospective, open-label trial had a 2-week placebo period, a 4-week upward drug titration/efficacy period, and a 12-week drug maintenance period. There were 1,084 evaluable patients (mean age 55.5 years; 65% men and 35% women; 79% white and 21% black; 75% <65 and 25% > or = 65 years old). At the end of the titration/efficacy phase, the mean +/- SD blood pressure (BP) decreased by -16.3 +/- 12.3/-12.5 +/- 5.9 mm Hg, (p < or = 0.0001). Amlodipine produced a goal BP response (sitting diastolic BP < or = 90 mm Hg, or a 10 mm Hg decrease) in 86.0% of patients overall. The BP response was greater in women (91.4%) than in men (83.0%, p < or = 0.001), and greater in those > or = 65 years old (91.5%) than in those < 65 years old (84.1%, p < or = 0.01); however, it was similar between whites and blacks (86.0% vs 85.9%, respectively, p = NS). The sex difference in BP response could not be fully explained by differences in age, weight, dose (mg/kg), race, baseline BP, or compliance, and there were no differences among women based on use of hormone replacement therapy. Amlodipine was well tolerated; mild to moderate edema was the most common adverse effect. Thus, amlodipine was effective and safe as once-a-day monotherapy in the treatment of mild to moderate hypertension in a community-based population. Women had a greater BP response to amlodipine.

Ca(2+)-channel blockers modulate the expression of interleukin-6 and interleukin-8 genes in human vascular smooth muscle cells

Ca(2+)-channel blockers at therapeutic concentrations were shown to modulate several processes underlying inflammation, such as growth factor-mediated activation of genes coding for the low density lipoprotein receptor and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase in human vascular smooth muscle cells (VSMC) (Block et al., 1991), and for interleukins in human mesangial cells (Roth et al., 1992). Two Ca(2+)-channel blockers, Manidipine (Roth et al., 1992) and Verapamil (Walz et al., 1990) have been shown to induce the expression of the gene coding for interleukin-6 (IL-6). Here we demonstrate that the four Ca(2+)-channel blockers, Amlodipine, Felodipine, Isradipine and Manidipine, at nanomolar concentrations, activate the transcription of the genes encoding IL-6 and IL-8 in primary human VSMC and fibroblasts. Ca(2+)-channel blocker-induced transcription is subsequently followed by secretion of the two ILs into the growth medium of the cells. In addition, we compared the action of the Ca(2+)-channel blockers with that of propranolol, a beta-adrenoceptor antagonist, or with furosemide, a diuretic, all of which are known to lower blood pressure. However, in contrast to the dihydropyridines, the two latter drugs failed to affect the expression of the two IL genes.