Amlodipine reduces transient myocardial ischemia in patients with coronary artery disease: double-blind Circadian Anti-Ischemia Program in Europe (CAPE Trial)

24-Hour Blood Pressure Control with Amlodipine: A Review of the Current Scenario

Introduction Hypertension is the leading cause of cardiovascular diseases and premature death worldwide. Antihypertensive therapy using calcium channel blockers (CCBs) is one of the preferred choices to treat blood pressure (BP) and control blood pressure variability (BPV). In contrast to clinic BP, 24-hour ambulatory BP monitoring (ABPM) has evolved into an accurate and reproducible tool for the assessment and management of hypertension. Amlodipine, a longer acting dihydropyridine CCB is effective for 24 hours BP control and also minimizing BPV. The present article is the comprehensive review highlighting the efficacy of amlodipine in controlling 24-hour BP and minimizing BPV from the review of recent studies.

Materials and Methods The literature search was done using PubMed, Google Scholar, and MEDLINE databases. The studies to be included for review, were identified through the keywords: “amlodipine,” “ambulatory BP monitoring (ABPM),”“blood pressure variability (BPV),” “CCBs,” and filtering articles published in English language only.

Results Pharmacological evidence suggests that amlodipine has the ability to block all the subtypes of CCBs such as L-, N-, P-, Q-, R-, and T-type. Various clinical studies reported that amlodipine is a powerful, well-tolerated, and safe antihypertensive agent which is widely used either alone or as a key component of combination therapy for control of 24 hours BP.

Conclusion Overall, amlodipine is a proven and effective antihypertensive drug and helpful in controlling 24-hour BP, minimizing BP variability and hence reducing the risk of cardiovascular complications.

Nitrendipine and Dementia: Forgotten Positive Facts?

Nowadays, there are about 50 million people suffering from dementia worldwide. In 2030, it is expected that there will be 82 million people living with dementia and in 2050, their number should reach 152 million. This increase in the number of people with dementia results in significant social and economic problems. Therefore, researchers attempt to reduce risk factors causing the development of dementia such as high blood pressure. Epidemiological studies have shown that hypertension increases the risk of dementia at an older age. It can, therefore, be assumed that hypertension therapy will reduce the risk of dementia. However, previous clinical studies have shown that the efficacy of different antihypertensive drugs differs in this respect. The drug group that appears to be the most effective in these analyses is calcium channel blockers (CCBs). The most significant preventive efficacy in terms of protection against dementia has been demonstrated with nitrendipine. Its use is, therefore, particularly advantageous in elderly patients with systolic hypertension who are at high risk of dementia. The purpose of this study is to restore the discussion on the prevention of vascular dementia and Alzheimer’s dementia with nitrendipine in indicated hypertonic patients. The authors performed a literature search of available sources describing the issue of dementia, hypertension and its treatment with nitrendipine. In addition, they made a comparison and evaluation of relevant findings. The results of the detected research studies indicate that nitrendipine is able to reduce the incidence of dementia [Alzheimer’s disease (AD), vascular and mixed] by 55%. The treatment of 1,000 patients with nitrendipine for 5 years may prevent 20 cases of dementia. However, what has not yet been explained is the temporal link between hypertension and dementia due to the long-time intervals between hypertension and the development of dementia.

Antianginal Therapy for Stable Ischemic Heart Disease

Chronic angina pectoris is associated with considerable morbidity and mortality, especially if treated suboptimally. For many patients, aggressive pharmacologic intervention is necessary in order to alleviate anginal symptoms. The optimal treatment of stable ischemic heart disease (SIHD) should be the prevention of angina and ischemia, with the goal of maximizing both quality and quantity of life. In addition to effective risk factor modification with lifestyle changes, intensive pharmacologic secondary prevention is the therapeutic cornerstone in managing patients with SIHD. Current guidelines recommend a multifaceted therapeutic approach with β-blockers as first-line treatment. Another important pharmacologic intervention for managing SIHD is nitrates. Nitrates can provide both relief of acute angina and can be used prophylactically before exposure to known triggers of myocardial ischemia to prevent angina. Additional therapeutic options include calcium channel blockers and ranolazine, an inhibitor of the late inward sodium current, that can be used alone or in addition to nitrates or β-blockers when these agents fail to alleviate symptoms. Ranolazine appears to be particularly effective for patients with microvascular angina and endothelial dysfunction. In addition, certain antianginal therapies are approved in Europe and have been shown to improve symptoms, including ivabradine, nicorandil, and trimetazidine; however, these have yet to be approved in the United States. Ultimately, there are several different medications available to the physician for managing the patient with SIHD having chronic angina, when either used alone or in combination. The purpose of this review is to highlight the most important therapeutic approaches to optimizing contemporary treatment in response to individual patient needs.

Combination therapy in the extended cardiovascular continuum: a focus on perindopril and amlodipine

The progression of cardiovascular disease could be regarded as following atherosclerosis-related and age-related pathways. The starting points for these pathways are different--risk factors or aortic ageing--but they conclude in the same way: end-stage heart disease. Together these interlinked pathways form the extended cardiovascular continuum. Renin-angiotensin-aldosterone system (RAAS) inhibitors have been shown to interrupt or slow the progression of cardiovascular disease along one pathway, the cardiovascular atherosclerotic continuum. Cardiovascular protection with RAAS inhibitors varies; different RAAS inhibitors offer different levels of protection. Similarly, calcium channel blockers (CCBs) also have clearly shown protective effect of cardiovascular system, especially as it regards cerebrovascular disease risk. The AngloScandinavian Cardiac Outcomes Trial (ASCOT) showed that a combination of the angiotensin-converting enzyme (ACE) inhibitor perindopril and CCB amlodipine offered better cardiovascular protection in at-risk hypertensive patients than beta-blocker and thiazide. By attenuating the deleterious effects of cardiovascular disease at multiple stages of the extended cardiovascular continuum on top of lowering blood pressure (BP), perindopril and amlodipine could interrupt and slow the progression of cardiovascular disease. These antihypertensive agents have complementary vascular effects that enhance cardiovascular protection and reduce side-effects. Evidence from ASCOT shows that antihypertensive and vascular effects of amlodipine with and without perindopril have translated into real-life clinical benefits. A strategy using ACE inhibitors and CCBs, such as perindopril and amlodipine, to target multiple stages in both pathways of cardiovascular disease could effectively reduce cardiovascular risk and lower BP.

Antihypertensive efficacy of triple combination perindopril/indapamide plus amlodipine in high-risk hypertensives: results of the PIANIST study (Perindopril-Indapamide plus AmlodipiNe in high rISk hyperTensive patients)

OBJECTIVE

Our objective was to evaluate a triple-drug antihypertensive strategy for blood pressure control in patients with difficult-to-treat hypertension.

DESIGN

The Perindopril-Indapamide plus AmlodipiNe in high rISk hyperTensive patients (PIANIST) trial was an observational, 4-month, open-label study.

PATIENTS AND INTERVENTIONS

A total of 4,731 patients at high or very high cardiovascular risk with hypertension that was not properly controlled [ , and for [corrected] whom study treatment (fixed-dose perindopril 10 mg/indapamide 2.5 mg + amlodipine 5 or 10 mg) was consistent with their existing therapeutic plan, were included.

OUTCOMES

One-sample t tests and Chi-squared tests were performed to evaluate changes in blood pressure.

RESULTS

Mean baseline office blood pressure (OBP) was 160.5 ± 13.3/93.8 ± 8.7 mmHg. After 4 months of therapy, OBP decreased by 28.3 ± 13.5/13.8 ± 9.4 to 132.2 ± 8.6/80.0 ± 6.6 mmHg (p < 0.0001). Blood pressure targets were reached by 72.0% of patients and by 81 and 91% of patients previously treated with an angiotensin-converting enzyme inhibitor/hydrochlorothiazide or an angiotensin receptor blocker/hydrochlorothiazide, respectively. Changes in OBP were 18.7 ± 8.3/9.7 ± 7.2 mmHg for grade 1 (n = 1,679), 30.4 ± 10.1/14.7 ± 8.6 mmHg for grade 2 (n = 2,397), and 45.4 ± 15.1/20.7 ± 12.1 mmHg for grade 3 patients (n = 655; all p < 0.0001). In patients who underwent ambulatory blood pressure monitoring (n = 104), 24-h mean blood pressure decreased from 147.4 ± 13.8/82.1 ± 11.9 to 122.6 ± 9.1/72.8 ± 7.4 mmHg (p < 0.0001). Ankle edema was infrequent (0.2% of patients).

CONCLUSION

Triple combination perindopril/indapamide/amlodipine was effectively and safely administered to a large population of high- and very high-risk hypertensive patients who had not reached target OBP values with previous treatment.

The clinical significance of continuous ECG (ambulatory ECG or Holter) monitoring of the ST-segment to evaluate ischemia: a review

Silent ischemia is a common manifestation of coronary artery disease (CAD). Continuous ECG (cECG) monitoring is an effective tool for assessing the frequency and duration of silent ischemic episodes for patients with CAD and for risk stratifying asymptomatic patients or those after an acute coronary syndrome by identifying those at increased risk for future cardiovascular events or death. cECG also allows monitoring of the effectiveness of therapy in patients with CAD. Treatment strategies targeted toward the elimination of silent ischemia have shown that revascularization was better than medical therapy in eliminating silent ischemia, but large scale, prospective studies targeting silent ischemia as a treatment endpoint are still lacking. Future research is warranted to study the effects of newer medical agents or the selected use of revascularization in those patients with persistent silent ischemia despite current medical regiments.

Telmisartan exerts pleiotropic effects in endothelial cells and promotes endothelial cell quiescence and survival

OBJECTIVE

Telmisartan, an angiotensin II type 1 receptor blocker, and amlodipine, a calcium channel blocker, are antihypertensive agents clinically used as monotherapy or in combination. They exert beneficial cardiovascular effects independently of blood pressure lowering and classic mechanisms of action. In this study, we investigate molecular mechanisms responsible for the off-target effects of telmisartan and telmisartan-amlodipine in endothelial cells (ECs), using an unbiased genomic approach.

APPROACH AND RESULTS

In human umbilical vein ECs, microarray analysis of gene expression followed by pathway enrichment analysis and quantitative polymerase chain reaction validation revealed that telmisartan modulates the expression of key genes responsible for cell cycle progression and apoptosis. Amlodipine's effect was similar to control. ECs exposed to telmisartan, but not amlodipine, losartan, or valsartan, exhibited a dose-dependent impairment of cell growth and failed to enter the S-phase of the cell cycle. Similarly, telmisartan inhibited proliferation in COS-7 cells lacking the angiotensin II type 1 receptor. In telmisartan-treated ECs, phosphorylation and activation of Akt, as well as MDM2, were reduced, leading to accumulation of p53 in the nucleus, where it represses the transcription of cell cycle-promoting genes. Phosphorylation of glycogen synthase kinase-3β was also reduced, resulting in rapid proteolytic turnover of CyclinD1. Telmisartan induced downregulation of proapoptotic genes and protected ECs from serum starvation-induced and 7-ketocholesterol-induced apoptosis.

CONCLUSIONS

Telmisartan exerts antiproliferative and antiapoptotic effects in ECs. This may account for the improved endothelial dysfunction observed in the clinical setting.

Optimization of blood pressure treatment with fixed-combination perindopril/amlodipine in patients with arterial hypertension

BACKGROUND

Fixed-dose combination treatments using an angiotensin-converting enzyme (ACE) inhibitor, such as perindopril, plus a calcium channel blocker (CCB), such as amlodipine, have been endorsed by guidelines because they improve blood pressure control and cardiovascular outcomes in hypertensive patients, while being well tolerated and well adhered to by patients.

OBJECTIVE

This study aimed to assess the blood pressure-lowering effects of fixed-combination perindopril/amlodipine in patients previously treated with an ACE inhibitor and/or a CCB.

METHODS

This was a prospective, real-life, open-label, longitudinal, phase IV study conducted in 223 outpatient medical centres across Slovakia. 2132 previously treated patients whose hypertension was insufficiently controlled at baseline or who tolerated treatment poorly were included. Patients were treated for 3 months with fixed-combination perindopril/amlodipine 5 mg/5 mg, 5 mg/10 mg, 10 mg/5 mg and 10 mg/10 mg. The main outcome measure was a reduction in mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) and achievement of blood pressure targets (SBP/DBP <140/90 mmHg or <130/80 mmHg for patients with type 2 diabetes mellitus or high cardiovascular risk).

RESULTS

After 3 months of treatment, mean ± SD SBP/DBP had decreased from 158.5 ± 17.5/93.6 ± 9.8 mmHg to 132.9 ± 10.6/80.7 ± 6.2 mmHg (p < 0.0001). In patients with grade 3 hypertension, mean ± SD changes from baseline in SBP/DBP were -45.4 ± 16.4/-20.0 ± 11.5 mmHg after 3 months (p < 0.0001). Blood pressure targets were reached by 74% of the overall patient population, 84% of patients with grade 1 hypertension, and 52% of difficult-to-treat patients with grade 3 hypertension. This treatment was associated with a 58% reduction in the number of patients with amlodipine-related ankle oedema compared with baseline.

CONCLUSION

Fixed-combination perindopril/amlodipine was well tolerated and resulted in statistically significant and clinically meaningful decreases in blood pressure.

Optimization of blood pressure treatment with fixed-combination perindopril/amlodipine in patients with arterial hypertension

BACKGROUND

Fixed-dose combination treatments using an angiotensin-converting enzyme (ACE) inhibitor, such as perindopril, plus a calcium channel blocker (CCB), such as amlodipine, have been endorsed by guidelines because they improve blood pressure control and cardiovascular outcomes in hypertensive patients, while being well tolerated and well adhered to by patients.

OBJECTIVE

This study aimed to assess the blood pressure-lowering effects of fixed-combination perindopril/amlodipine in patients previously treated with an ACE inhibitor and/or a CCB.

METHODS

This was a prospective, real-life, open-label, longitudinal, phase IV study conducted in 223 outpatient medical centres across Slovakia. 2132 previously treated patients whose hypertension was insufficiently controlled at baseline or who tolerated treatment poorly were included. Patients were treated for 3 months with fixed-combination perindopril/amlodipine 5 mg/5 mg, 5 mg/10 mg, 10 mg/5 mg and 10 mg/10 mg. The main outcome measure was a reduction in mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) and achievement of blood pressure targets (SBP/DBP <140/90 mmHg or <130/80 mmHg for patients with type 2 diabetes mellitus or high cardiovascular risk).

RESULTS

After 3 months of treatment, mean ± SD SBP/DBP had decreased from 158.5 ± 17.5/93.6 ± 9.8 mmHg to 132.9 ± 10.6/80.7 ± 6.2 mmHg (p < 0.0001). In patients with grade 3 hypertension, mean ± SD changes from baseline in SBP/DBP were -45.4 ± 16.4/-20.0 ± 11.5 mmHg after 3 months (p < 0.0001). Blood pressure targets were reached by 74% of the overall patient population, 84% of patients with grade 1 hypertension, and 52% of difficult-to-treat patients with grade 3 hypertension. This treatment was associated with a 58% reduction in the number of patients with amlodipine-related ankle oedema compared with baseline.

CONCLUSION

Fixed-combination perindopril/amlodipine was well tolerated and resulted in statistically significant and clinically meaningful decreases in blood pressure.

Emotional stressors trigger cardiovascular events

AIMS

To describe the relation between emotional stress and cardiovascular events, and review the literature on the cardiovascular effects of emotional stress, in order to describe the relation, the underlying pathophysiology, and potential therapeutic implications.

MATERIALS AND METHODS

Targeted PUBMED searches were conducted to supplement the authors' existing database on this topic.

RESULTS

Cardiovascular events are a major cause of morbidity and mortality in the developed world. Cardiovascular events can be triggered by acute mental stress caused by events such as an earthquake, a televised high-drama soccer game, job strain or the death of a loved one. Acute mental stress increases sympathetic output, impairs endothelial function and creates a hypercoagulable state. These changes have the potential to rupture vulnerable plaque and precipitate intraluminal thrombosis, resulting in myocardial infarction or sudden death.

CONCLUSION

Therapies targeting this pathway can potentially prevent acute mental stressors from initiating plaque rupture. Limited evidence suggests that appropriately timed administration of beta-blockers, statins and aspirin might reduce the incidence of triggered myocardial infarctions. Stress management and transcendental meditation warrant further study.

Cardio classics revisited: focus on the role of amlodipine

Amlodipine is a long-acting, dihydropyridine calcium antagonist now widely used for lowering of elevated blood pressure. In recent years it has been shown to be effective in reducing both blood pressure and risk of cardiovascular (CV) events when used in combination with other antihypertensive agents of different classes. Strong evidence of cardiovascular benefit has been attained for combination of amlodipine with diuretics or angiotensin converting enzyme (ACE) inhibitors in a number of high-risk CV groups, including those with established coronary artery disease, diabetes, and at risk of renal disease. Combination therapies of amlodipine with other agents eliciting renin-angiotensin-aldosterone system blockade (angiotensin II receptor blockers or renin inhibitors) have been shown to be effective blood pressure-lowering strategies, but await the results of ongoing trials for direct evidence of benefit for renal disease progression and CV morbidity and mortality.

Potent anti-ischaemic effects of statins in chronic stable angina: incremental benefit beyond lipid lowering?

Aims

The DoUble-blind Atorvastatin AmLodipine (DUAAL) trial investigated whether atorvastatin decreases ischaemia by a vascular benefit, independent of low-density lipoprotein cholesterol lowering, in patients with coronary artery disease (CAD), both alone and in combination with the traditional anti-anginal therapy, amlodipine.

Methods and results

Randomized, double-blind, parallel-group, multicountry trial (2 weeks run-in and 24 weeks active therapy) comparing three treatments: amlodipine, atorvastatin, and amlodipine + atorvastatin; in 311 patients (78% male; mean age 62 years) with stable angina (≥2 attacks/week), CAD history, ≥3 transient myocardial ischaemia (TMI) episodes, and/or ≥15 min ischaemia on 48 h ambulatory electrocardiographic (AECG) monitoring. Efficacy variables were change in TMI by AECG, exercise ischaemia, angina diary data, and inflammatory biomarkers at Week 26. There was a comparable, highly significant decrease in TMI with amlodipine and atorvastatin, but no additional benefit for the combination. More than 50% of patients became TMI-free in all three groups and this was accompanied by a comparable, marked reduction in angina and nitroglycerin consumption. High-sensitivity C-reactive protein fell by 40% in patients receiving atorvastatin but there was no change with amlodipine. Adverse events were comparable among groups.

Conclusion

Atorvastatin was as potent an anti-ischaemic agent as amlodipine. Future studies of combination therapies will be instructive.

Clinical trial registration information: National clinical trial number: NCT00159718, protocol number A0531031 listed on http://clinicaltrials.gov/.

Silent myocardial ischemia

Although much progress has been made in reducing mortality from ischemic cardiovascular disease, this condition remains the leading cause of death throughout the world. This might in part be due to the fact that over half of patients have a catastrophic event (heart attack or sudden death) as their initial manifestation of coronary disease. Contributing to this statistic is the observation that the majority of myocardial ischemic episodes are silent, indicating an inability or failure to sense ischemic damage or stress on the heart. This review examines the clinical characteristics of silent myocardial ischemia, and explores mechanisms involved in the generation of angina pectoris. Possible mechanisms for the more common manifestation of injurious reductions in coronary flow; namely, silent ischemia, are also explored. A new theory for the mechanism of silent ischemia is proposed. Finally, the prognostic importance of silent ischemia and potential future directions for research are discussed.

Circadian patterns in the onset of cardiogenic acute pulmonary edema

BACKGROUND

Circadian patterns of onset favoring the morning hours have been demonstrated for many cardiovascular disorders. Although much is known about cardiogenic acute pulmonary edema (CAPE), the relationship between time of day and CAPE episode onset has not been previously studied.

METHODS

We examined 154 consecutive episodes of CAPE treated at an urban community hospital to determine whether circadian patterns existed in the time these episodes began.

RESULTS

For all episodes, a significant circadian pattern existed, with peak onset between 6:00 and 11:59 A.M. (p < 0.01). When CAPE episodes were analyzed by the most probable precipitant of pulmonary edema, only the pattern for patients with progressive symptoms, showing a peak in the 6:00 and 11:59 A.M. interval, was statistically significant (p < 0.01). Although a similar trend existed for CAPE occurring in association with acute myocardial infarction, the pattern fell short of statistical significance (p = 0.09).

CONCLUSIONS

These data suggest that circadian patterns favoring the morning hours exist for episodes of CAPE, and that patterns may vary depending on the precipitant of the episode.

Monotherapy with amlodipine or atenolol versus their combination in stable angina pectoris

BACKGROUND

The basic cause of angina pectoris is imbalance between the metabolic needs of the myocardium and the capacity of the coronary circulation to deliver sufficient oxygenated blood to satisfy these needs.

HYPOTHESIS

The study was undertaken to evaluate whether the effect of combined amlodipine and atenolol therapy on patients with stable angina pectoris and with ST-depression during exercise testing and 48-h ambulatory electrocardiographic monitoring is superior to that of either agent given alone.

METHODS

Patients with stable angina pectoris and ST depression during exercise and ambulatory monitoring were randomized to receive amlodipine (n = 116) or atenolol (n = 116), or both (n = 119). All patients were also treated with short- and long-acting nitrates. The design was a double-blind, randomized, triple-arm parallel group study with 10 weeks of administration of the test medication.

RESULTS

In terms of time to onset of ST depression > 1 mm, time to onset of angina, total exercise time, maximum achieved workload, and peak intensity of angina, amlodipine and atenolol alone were as effective as their combination. During ambulatory monitoring, atenolol was more effective than amlodipine regarding total time and number of ST-depression episodes, and as effective as the combined drugs.

CONCLUSION

For individual patients with stable angina pectoris, combination of a beta blocker with a calcium antagonist is not necessarily more effective than either drug given alone.

Chronobiology and chronotherapy of ischemic heart disease

The occurrence of the clinical manifestations of ischemic heart disease (IHD)--myocardial ischemia and angina pectoris, acute myocardial infarction, and sudden cardiac death--is unevenly distributed during the 24 h with greater than expected events during the initial hours of the daily activity span and in the late afternoon or early evening. Such temporal patterns result from circadian rhythms in pathophysiological mechanisms plus cyclic environmental stressors that trigger ischemic events. Both the pharmacokinetics (PK) and pharmacodynamics (PD) of many, though not all, anti-ischemic oral nitrate, calcium channel blocker, and beta-adrenoceptor antagonist medications have been shown to be influenced by the circadian time of their administration. The requirement for preventive and therapeutic interventions varies predictably during the 24 h, and thus therapeutic strategies should also be tailored accordingly to optimize outcomes. During the past decade, two first generation calcium channel blocker chronotherapies have been developed, trialed, and marketed in North America for the improved treatment of IHD. Nonetheless, there has been relatively little investigation of the administration-time (circadian rhythm) dependencies of the PK and PD of conventional anti-ischemic medications, and there has been little progress in the development of new generation IHD chronotherapies. Available epidemiologic, pharmacologic, and clinico-therapeutic evidence demonstrates how the chronobiologic approach to IHD can contribute new insight and opportunities to improve drug design and drug delivery to enhance therapeutic outcomes.

Amlodipine Besylate versus Candesartan Cilexetil in Hypertensive Patients - Office and Self-Measured Blood Pressure : A Randomised, Double-Blind, Comparative, Multicentre Trial

OBJECTIVE

The aim of this study was to compare the antihypertensive efficacy and tolerability of the calcium channel antagonist amlodipine besylate versus the angiotensin II type 1 receptor antagonist candesartan cilexetil in hypertensive patients.

PATIENTS AND METHODS

After a 2-week placebo washout period, 326 patients with essential hypertension were randomised to receive amlodipine 5mg once daily or candesartan cilexetil 8mg once daily in a double-blind, parallel-group design with a 12-week active treatment period followed by a 4-day placebo drug-free period. The initial daily dose could be doubled at week 6 if office diastolic blood pressure (DBP) was still >/=90mm Hg. BP changes were assessed daily through patient self-measurements, and fortnightly by office BP measurements.

RESULTS

A total of 294 patients (151 amlodipine and 143 candesartan cilexetil) were included in the per-protocol analysis of the primary endpoint of BP change from baseline at 12 weeks. Reductions in sitting office systolic BP (SBP) [amlodipine 24.4mm Hg, candesartan cilexetil 22.3mm Hg] and DBP (amlodipine 14.9mm Hg, candesartan cilexetil 14.8mm Hg) were statistically equivalent within the chosen range of equivalence (5mm Hg for SBP and 3mm Hg for DBP). The proportion of controlled patients (office BP <140/90mm Hg) at the end of therapy was similar in both treatment groups (amlodipine 46.9%, candesartan cilexetil 44.4%). The reduction in self-measured DBP was significantly greater (p < 0.05) for amlodipine (7.2mm Hg) compared with candesartan cilexetil (4.8mm Hg). There was no significant difference between the two treatments in the incidence of adverse events reported.

CONCLUSIONS

Amlodipine besylate and candesartan cilexetil were both very effective in lowering office BP after 12 weeks of treatment. There was a trend towards a better self-measured BP reduction with amlodipine compared with candesartan cilexetil. The overall incidence of adverse events was comparable between the two treatments.

Silent myocardial ischaemia: clinical relevance and treatment

Transient myocardial ischaemia in the absence of chest pain ('silent ischaemia') commonly occurs in patients with coronary artery disease (CAD) and has important prognostic implications. However, doubts exist as to whether and how silent ischaemia should be managed. In the present article we review current knowledge regarding silent ischaemia and the role of recently developed drugs that may be effective to control its occurrence. Since the description in the 1770s of the syndrome of 'angina pectoris' by William Heberden, the importance of chest pain for the diagnosis of CAD has remained un-abated. However, several decades ago it became apparent that both myocardial infarctions and transient episodes of myocardial ischaemia could occur in the absence of chest pain. Indeed, a large proportion of patients with CAD have both silent and painful myocardial ischaemia as a manifestation of CAD. Whether the presence of asymptomatic ischaemic electrocardiographic changes in patients with CAD has prognostic importance and whether it needs medical or surgical treatment has been a matter of speculation for several decades.

Current strategies for the prevention of angina in patients with stable coronary artery disease

PURPOSE OF REVIEW

Angina pectoris affects at least 6.6 million people in the US and approximately 400,000 new cases of stable angina occur each year. Angina may be one of the first signs of ischemic heart disease, although it is likely not causally related to the likelihood of plaque rupture leading to an acute coronary syndrome. Modalities for treatment of angina should be used maximally to improve quality of life and decrease cardiovascular morbidity and mortality. The current recommended pharmacologic and invasive approaches, as well as novel therapies, are reviewed.

RECENT FINDINGS

Antiischemic agents, including beta-blockers, nitrates and calcium channel blockers, remain the mainstay in the prevention of angina. Revascularization via percutaneous interventions or coronary bypass surgery are appropriate in specific cases or when medical treatment fails. Noninvasive treatment options for refractory angina, metabolic agents, and vasodilator therapies are adding to the armamentarium to prevent and treat angina.

SUMMARY

A multifaceted approach is optimal to address the prevention of angina. Once angina is recognized, there are many modalities that lessen the incidence of daily life-induced and exercise-induced angina and ischemia. Angina management is best addressed by pharmacologic and lifestyle interventions.

Effect of exercise training on myocardial blood flow in patients with stable coronary artery disease

BACKGROUND

The mechanisms by which exercise training benefits patients with coronary artery disease (CAD) are unclear but may include improved myocardial circulation. The aim of this study was to investigate the effect of exercise training on myocardial blood flow (MBF) and coronary flow reserve (CFR) in patients with stable CAD.

METHODS

Twelve patients with documented CAD and ischemic ST-segment depression during exercise testing were randomized to exercise training (n = 7) or sedentary life style (control; n = 5) and underwent rubidium-82 positron emission tomography pre- and postintervention. Global left ventricle MBF and regional MBF in 17 left ventricular segments were calculated. Segments with <75% uptake (2 SD below normal) on stress uptake images were defined as abnormal.

RESULTS

Exercise training increased global CFR by 20.8% +/- 27.9% versus control (10.5 +/- 24.1%, P = .0001). In normal segments (exercise training: n = 91; control: n = 46), exercise training did not change resting MBF (-14.1% +/- 16.3% vs -8.8% +/- 15.6%) and hyperemic MBF (-1.93% +/- 19.1% vs 2.86% +/- 20.5%, P = NS) and increased in CFR compared to control (17.0% +/- 25.5% vs 11.3% +/- 23.5%, P = .01). In abnormal segments, the change in resting MBF was not significantly different (-12.6% +/- 18.5% exercise [28 segments] vs -2.9% +/- 18.0% control [39 segments], P = NS). A significant increase was seen in hyperemic MBF with exercise (12.5% +/- 22.1% vs 2.6% +/- 16.3%, P = .02) and CFR (32.8% +/- 32.3% vs 9.5% +/- 24.8%, P = .001).

CONCLUSIONS

Exercise training increased CFR in normal and diseased segments, and increased hyperemic flow in diseased segments. These data provide preliminary evidence in support of a favorable effect of exercise training on blood flow to ischemic myocardium.

Natural and unnatural triggers of myocardial infarction

Previous analyses have suggested that factors that stimulate the sympathetic nervous system and catecholamine release can trigger acute myocardial infarction. The wake-up time, Mondays, winter season, physical exertion, emotional upset, overeating, lack of sleep, cocaine, marijuana, anger, and sexual activity are some of the more common triggers. Certain natural disasters such as earthquakes and blizzards have also been associated with an increase in cardiac events. Certain unnatural triggers may play a role including the Holiday season. Holiday season cardiac events peak on Christmas and New Year. A number of hypotheses have been raised to explain the increase in cardiac events during the holidays, including overeating, excessive use of salt and alcohol, exposure to particulates, from fireplaces, a delay in seeking medical help, anxiety or depression related to the holidays, and poorer staffing of health care facilities at this time. War has been associated with an increase in cardiac events. Data regarding an increase in cardiac events during the 9/11 terrorist attack have been mixed. Understanding the cause of cardiovascular triggers will help in developing potential therapies.

Drug treatment of stable angina pectoris in the elderly: defining the place of calcium channel antagonists

Chronic stable angina pectoris (CSAP) resulting from coronary artery disease (CAD) is common in elderly patients, and significantly reduces their quality of life. Myocardial revascularisation procedures in this age group entail significant risks, largely related to comorbidities rather than advanced age itself. Coronary artery anatomy is more likely to be technically unsuitable for revascularisation and angina more resistant to drug treatment. Therefore, elderly patients often take combinations of antianginal drugs. Calcium channel antagonists (CCAs) are effective antianginal drugs first introduced for clinical use in the late 1970's. They reduce myocardial ischaemia by both causing vasodilatation of coronary resistance vessels and reducing cardiac workload (negative inotropic effect). However, adverse effects related to abrupt arterial vasodilatation limited the tolerability of these short acting 'first generation' drugs (nifedipine, verapamil and diltiazem). Furthermore, short acting nifedipine may occasionally increase both the frequency of angina pectoris and mortality in patients with CAD. Since then, long acting formulations of first generation agents and new chemical entities (second and third generation drugs) have been developed. These are well tolerated and effective at attenuating both myocardial ischaemia and the frequency and severity of angina pectoris in most patients with stable CAD. Current guidelines on the drug treatment of CSAP propose that beta-adrenoceptor antagonists (beta-blockers) should be used as first line medication primarily for their prognostic benefits, and that CCAs need only be introduced if beta-blockers are not tolerated, contraindicated or ineffective. Despite this, there is a wealth of evidence from clinical trials that demonstrate equal antianginal efficacy for CCAs and beta-blockers. The presence of chronic heart failure and prior myocardial infarction are clear indications for the use of beta-blockers in preference to CCAs for the treatment of CSAP. However, in patients with both CSAP and hypertension, second and third generation CCAs may offer prognostic benefits of similar magnitude to those provided by beta-blockers. Therefore, antianginal drug therapy must be tailored to the individual needs and comorbidities of each elderly patient.

Novel Vascular Biology of Third-Generation L-Type Calcium Channel Antagonists

Calcium channel blockers (CCBs) were developed as vasodilators, and their use in cardiovascular disease treatment remains largely based on that mechanism of action. More recently, with the evolution of second- and third-generation CCBs, pleiotropic effects have been observed, and at least some of CCBs’ benefit is attributable to these mechanisms. Understanding these effects has contributed greatly to elucidating disease mechanisms and the rationale for CCB use. Furthermore, this knowledge might clarify why drugs are useful in some disease states, such as atherosclerosis, but not in others, such as heart failure. Although numerous drugs used in the treatment of vascular disease, including statins and angiotensin-converting–enzyme inhibitors, have well-described pleiotropic effects universally accepted to contribute to their benefit, little attention has been paid to CCBs’ potentially similar effects. Accumulating evidence that at least 1 CCB, amlodipine, has pharmacologic actions distinct from L-type calcium channel blockade prompted us to investigate the pleiotropic actions of amlodipine and CCBs in general. There are several areas of research; foci here are (1) the physicochemical properties of amlodipine and its interaction with cholesterol and oxidants; (2) the mechanism by which amlodipine regulates NO production and implications; and (3) amlodipine’s role in controlling smooth muscle cell proliferation and matrix formation.

Calcium antagonists in the treatment of hypertension in patients with ischaemic heart disease

Are lives saved or heart attacks prevented by antihypertensive therapy, as a result of blood pressure reduction alone, or because of other properties of the antihypertensive medications which are independent of blood pressure lowering? Long-acting calcium antagonists seem to be as effective as thiazide diuretics and angiotensin-converting enzyme (ACE) inhibitors in preventing all-cause mortality and stroke in patients with hypertension, but are probably inferior to ACE inhibitors in preventing coronary artery disease. In patients with symptomatic coronary artery disease, calcium antagonists are generally as effective as beta-blockers in relieving angina and improving exercise time-to-onset of angina or ischaemia. Unstable angina or myocardial infarction require treatment with a beta-blocker, with an ACE inhibitor added when necessary for blood pressure control or if there is significant left ventricular (LV) dysfunction. If beta-blockers are contraindicated and if there is no LV dysfunction, a non-dihydropyridine calcium antagonist can be substituted.

Effects of amlodipine on ischemia after percutaneous transluminal coronary angioplasty: secondary results of the Coronary Angioplasty Amlodipine Restenosis (CAPARES) Study

BACKGROUND

Despite successful coronary angioplasty (PTCA), patients may have ischemia after the procedure because of the overall coronary disease and luminal renarrowing at the lesion sites. The aim of this study was to examine the effects of the calcium-channel blocker amlodipine on post-PTCA ischemia.

METHODS

In a prospective, double-blind design, patients were randomized to receive 10 mg of amlodipine or placebo 2 weeks before angioplasty. Exercise tests and 48-hour ambulatory electrocardiography recordings were performed in 405 patients, 2 weeks before and 2 and 20 weeks (early and late) after PTCA.

RESULTS

There were no differences in clinical and angiographic baseline characteristics between the treatment groups. Ischemia and angina were equally distributed before PTCA, and no difference in restenosis was found between the groups at follow-up. The incidence of angina was significantly lower in the amlodipine group compared with the placebo group both early and late after PTCA (P =.04 and.03). Exercise-induced ischemia was reduced by 40% (P =.009) early and 34% (P =.02) late after PTCA in the amlodipine group, and ischemia on ambulatory electrocardiography was reduced by 18% early and 28% late after PTCA compared with placebo (P =.06 and P =.009).

CONCLUSION

Ischemia and angina occurred after successful PTCA and were significantly reduced by amlodipine.

Amlodipine versus Angiotensin-receptor blockers for nonhypertension indications

OBJECTIVE

To review the efficacy and safety data of amlodipine and the angiotensin-receptor blockers (ARBs), focusing on heart failure, angina, percutaneous coronary intervention (PCI), and renal protection.

DATA SOURCE

A MEDLINE search (1966-December 2001) was completed using amlodipine, angiotensin-receptor antagonist, losartan, valsartan, candesartan, and telmisartan as key words. English-language articles were identified and included.

STUDY SELECTION AND DATA EXTRACTION

All identified articles were evaluated. Articles representative of the subject matter of our review were included.

DATA SYNTHESIS

Amlodipine and the ARBs lower blood pressure to a similar extent. Amlodipine is an effective antianginal agent, whereas ARBs are not. However, amlodipine is not effective in the treatment of heart failure; ARBs may be useful in this setting. ARBs are also effective in preserving renal function and may provide some protection from restenosis in patients who have had a PCI. The ARBs may also be useful in preventing both diabetic and nondiabetic nephropathy.

CONCLUSIONS

Concomitant disease states should be considered when choosing between an ARB and amlodipine for the management of hypertension.

Medical treatment of myocardial ischemia in coronary artery disease: effect of drug regime and irregular dosing in the CAPE II trial

OBJECTIVES

The Circadian Anti-ischemia Program in Europe (CAPE II) compared the efficacy of amlodipine and diltiazem (Adizem XL) and the combination of amlodipine/atenolol and diltiazem (Adizem XL)/isosorbide 5-mononitrate on exercise and ambulatory myocardial ischemia during regular therapy and after omission of medication.

BACKGROUND

The optimal medical therapy for ischemia suppression and the impact of irregular dosing using agents with different pharmacologic properties has not been established in patients with coronary disease.

METHODS

Patients with > or = 4 ischemic episodes or > or = 20 min of ST segment depression on 72-h electrocardiogram were randomized to amlodipine 10 mg once daily or diltiazem (Adizem XL) 300 mg once daily in a 14-week double-blind randomized multicountry study. In the second phase, atenolol 100 mg was added to amlodipine and isosorbide 5-mononitrate 100 mg to diltiazem (Adizem XL). Ambulatory monitoring (72 h) and exercise testing were repeated after both phases, on treatment and after a 24-h drug-free interval.

RESULTS

Both monotherapy with amlodipine and diltiazem (Adizem XL) were effective on symptoms and ambulatory and exercise ischemia. Combination therapy reduced ischemia further, with amlodipine/atenolol superior to diltiazem (Adizem XL)/isosorbide 5-mononitrate. Amlodipine/atenolol was significantly superior during the drug-free interval with maintenance of ischemia reduction.

CONCLUSIONS

Amlodipine, with its intrinsically long half-life alone or together with beta-blocker, is likely to produce superior ischemia reduction in clinical practice when patients frequently forget to take medication or dose irregularly.

Restenosis and clinical outcome in patients treated with amlodipine after angioplasty: results from the Coronary AngioPlasty Amlodipine REStenosis Study (CAPARES)

OBJECTIVES

Our intent was to investigate the effect of the dihydropyridine calcium channel blocker amlodipine on restenosis and clinical outcome in patients undergoing percutaneous transluminal coronary angioplasty (PTCA).

BACKGROUND

Amlodipine has sustained vasodilatory effects and relieves coronary spasm, which may reduce luminal loss and clinical complications after PTCA.

METHODS

In a prospective, double-blind design, 635 patients were randomized to 10 mg of amlodipine or placebo. Pretreatment with the study drug started two weeks before PTCA and continued until four months after PTCA. The primary angiographic end point was loss in minimal lumen diameter (MLD) from post-PTCA to follow-up, as assessed by quantitative coronary angiography (QCA). Clinical end points were death, myocardial infarction, coronary artery bypass graft surgery and repeat PTCA (major adverse clinical events).

RESULTS

Angioplasty was performed in 585 patients (92.1%); 91 patients (15.6%) had coronary stents implanted. Follow-up angiography suitable for QCA analysis was done in 236 patients in the amlodipine group and 215 patients in the placebo group (per-protocol group). The mean loss in MLD was 0.30 +/- 0.45 mm in the amlodipine group versus 0.29 +/- 0.49 mm in the placebo group (p = 0.84). The need for repeat PTCA was significantly lower in the amlodipine versus the placebo group (10 [3.1%] vs. 23 patients [7.3%], p = 0.02, relative risk ratio [RR]: 0.45, 95% confidence interval [CI]: 0.22 to 0.91), and the composite incidence of clinical events (30 [9.4%] vs. 46 patients (14.5%), p = 0.049, RR: 0.65, CI: 0.43 to 0.99) within the four months follow-up period (intention-to-treat analysis).

CONCLUSIONS

Amlodipine therapy starting two weeks before PTCA did not reduce luminal loss, but the incidence of repeat PTCA and the composite major adverse clinical events were significantly reduced during the four-month follow-up period after PTCA with amlodipine as compared with placebo.

Modification of high blood pressure after myocardial infarction

The treatment of high blood pressure (BP) after myocardial infarction is extremely important to decrease reinfarction and mortality. BP should be controlled more strictly in this high-risk hypertensive population. Recently, many clinical trials have demonstrated the benefits of lifestyle modification and antihypertensive agents, particularly beta-blockers and angiotensin-converting-enzyme inhibitors for the treatment of acute myocardial infarction. Treatment with these agents that modify BP may benefit even normotensive patients after a myocardial infarction, although the benefit is greater in hypertensives.

Amlodipine reduces myocardial ischaemia during exercise without compromising left ventricular function in patients with silent ischaemia: a randomised, double-blind, placebo-controlled study

BACKGROUND

Left ventricular systolic function is reduced during episodes of silent ischaemia in patients with coronary artery disease (CAD). In most normal subjects left ventricular ejection fraction (LVEF) increases at least 5% during exercise whereas LVEF often remains unchanged or decreases in patients with CAD. The anti-ischaemic effect of calcium antagonists is well documented including a capability to reduce exercise-induced electrocardiographic ST-depressions, whereas the effect of these drugs on LV volume changes during exercise in patients with silent ischaemia is unknown.

AIM

The aim of this study was to evaluate the effect of amlodipine on rest and exercise LVEF in patients with silent ischaemia.

METHODS

Twenty-one patients completed a double-blind placebo-controlled cross-over study. Conventional exercise test and radionuclide cardiographies during exercise were used for determining haemodynamic parameters.

RESULTS

Exercise-induced electrocardiographic ST-depressions were reduced in 83% of the patients having ST-deviations during placebo even though 10 patients were already treated with a beta-blocker. Amlodipine did not affect left ventricular systolic function compared to placebo, neither at rest nor during exercise.

CONCLUSION

The results indicated that amlodipine is a safe anti-ischaemic drug in patients with silent ischaemia concerning cardiac function.

Effect of amlodipine on exercise-induced platelet activation in patients affected by chronic stable angina

BACKGROUND

Literature concerning exercise-induced platelet activation in chronic stable angina is somewhat confusing. The reason lies in the type of exercise as well as in methodological problems. A powerful, recently introduced procedure to detect platelet activation is flow cytometry. Platelet response to activating factors is mediated by calcium uptake; however, calcium antagonist effect on platelet activity is still unclear.

HYPOTHESIS

The study was undertaken to investigate exercise-induced platelet activation before and after treatment with amlodipine in chronic stable angina.

METHODS

Twenty patients with chronic stable angina were entered into the study. Each subject underwent a symptom-limited cycloergometer stress test following a washout period of 2 weeks. Blood samples were collected before and immediately after exercise. All subjects were then randomized into two groups of 10 patients each, with Group 1 and Group 2 taking amlodipine 10 mg/day, and placebo for 4 weeks, respectively. They subsequently underwent a second exercise stress test, and blood samples were obtained before and immediately after exercise. Flow-cytometric evaluation of platelet activity was performed in order to recognize GMP-140 expression on platelet membrane.

RESULTS

Strenuous exercise induced a significant increase in platelet activation in all subjects prior to therapy. No significant differences were observed in platelet activity at rest between Groups 1 and 2, whereas a significant decrease in exercise-induced platelet activation was demonstrated in Group 1 compared with Group 2.

CONCLUSION

Our data provide evidence of the favorable effect of amlodipine on exercise-induced platelet activation in patients affected by chronic stable angina.

Combination of calcium channel blockers and beta-blockers for patients with exercise-induced angina pectoris: beneficial effect of calcium channel blockers largely determined by their effect on heart rate

The combination of calcium channel blockers and beta-blockers is more effective for the treatment of exercise-induced angina pectoris than beta-blocker monotherapy. As ischemia in exercise-induced angina is essentially preceded by an increase in heart rate, calcium channel blockers with a negative chronotropic property may perform better for this purpose than nonchronotropic compounds. A 335-patient, 10-week, double-blind, parallel-group comparison of amlodipine 5 mg and 10 mg, diltiazem 200 mg and 300 mg, and mibefradil 50 mg and 100 mg treatment added to baseline beta-blocker treatment was performed. Exercise testing (ETT) was performed by bicycle ergometry. All of the calcium channels blockers significantly delayed the onset of 1 mm ST-segment depression on ETT (p < 0.001 for any treatment vs. baseline). In addition, mibefradil, in both low- and high-dose treatments, produced the largest delays (low dose: different from diltiazem and amlodipine by 24.1 and 29.8 seconds, respectively, p < 0.003 and < 0.001; high dose: different from diltiazem and amlodipine by 33.7 and 37.0 seconds, respectively, p < 0.001 and < 0.001). A stepwise logistic regression analysis revealed that this beneficial effect of calcium channel blockers was largely dependent on their effect on heart rate. Serious symptoms of dizziness likewise occurred significantly more frequently on mibefradil (p < 0.05 vs. diltiazem) and urged no fewer than 19 patients on mibefradil to withdraw from the trial. The authors conclude that calcium channel blockers with a negative chronotropic property provide a better delay of ischemia in patients with exercise-induced angina, but the concomitant risk of intolerable dizziness may reduce this benefit.

Combination of calcium channel blockers and beta blockers for patients with exercise-induced angina pectoris: a double-blind parallel-group comparison of different classes of calcium channel blockers. The Netherlands Working Group on Cardiovascular Research (WCN)

The combination of calcium channel blockers and beta blockers is more effective for the treatment of exercise-induced angina pectoris than beta blocker monotherapy. Since ischemia in exercise-induced angina is essentially preceded by an increase in heart rate, calcium channel blockers with negative chronotropic property may perform better for this purpose than nonchronotropic compounds. A 335-patient, 10-week, double-blind, parallel-group comparison of amlodipine 5 and 10 mg, diltiazem XR 200 and 300 mg, and mibefradil 50 and 100 mg treatment added to baseline beta blocker treatment was performed. Exercise testing (ETT) was performed by bicycle ergometry. Although none of the calcium channel blockers improved duration of exercise or amount of workload, all of them significantly delayed onset of 1 mm ST segment depression on ETT (p<0.001 for any treatment versus baseline). In addition, mibefradil, both low- and high-dose treatment, produced the largest delays (low dose: different from diltiazem and amlodipine by 24.1 and 29.8 s, p<0.003 and <0.001, respectively; high dose: different from diltiazem and amlodipine by 33.7 and 37.0 s, p<0.001 and <0.001, respectively). These effects were linearly correlated to the amount of rate pressure product (RPP) reduction. Serious symptoms of dizziness likewise occurred significantly more frequently with mibefradil (p<0.05) and led 19 patients taking mibefradil to withdraw from the trial. The authors conclude that calcium channel blockers with negative chronotropic property provide better delay of ischemia in patients with exercise-induced angina but that the concomitant risk of intolerable dizziness largely reduces this benefit.

Combination of calcium channel blockers and beta-adrenoceptor blockers for patients with exercise-induced angina pectoris: a double-blind parallel-group comparison of different classes of calcium channel blockers. Netherlands Working Group on Cardiovascular Research (WCN)

AIMS

The combination of calcium channel blockers and beta-adrenoceptor blockers is more effective for the treatment of exercise-induced angina pectoris than beta-adrenoceptor blocker monotherapy. As ischaemia in exercise-induced angina is preceded by increase in heart rate, calcium channel blockers with negative chronotropic properties may perform better for this purpose than nonchronotropic compounds.

METHODS

A 335 patient double-blind parallel-group study comparing 14 day treatment with amlodipine 5 and 10 mg, with diltiazem 200 and 300 mg, and mibefradil 50 and 100 mg added to baseline beta-adrenoceptor blocker treatment was performed. Exercise testing (ETT) was performed by bicycle ergometry.

RESULTS

Although none of the calcium channel blockers improved duration of exercise or amount of workload, all significantly delayed onset of 1 mm ST-segment depression on ETT (P<0.001 for any treatment vs baseline). In addition, mibefradil, both low and high dose treatment, produced the longest delays (low dose: different from diltiazem and amlodipine by 24.1 and 29.8 s, respectively, P<0. 003 and <0.001; high dose: different from diltiazem and amlodipine by 33.7 and 37.0 s, respectively, P<0.001 and <0.001). These effects were linearly correlated with the reduction in rate pressure product (RPP). Serious symptoms of dizziness occurred significantly more frequently on mibefradil (P<0.05), and 19 patients on mibefradil withdrew from trial.

CONCLUSIONS

Calcium channel blockers with negative chronotropic properties provide greater delay of ischaemia in patients with exercise-induced angina, but the concomitant risk of intolerable dizziness attenuates this benefit.

Anti-ischemic effects of amlodipine in patients with stable angina pectoris and myocardial ischemia during daily life. Amlodipine Study Group

Ambulatory electrocardiographic monitoring was used to assess the anti-ischemic effects of amlodipine in a subset of 56 patients enrolled in a 14-week withdrawal study; amlodipine therapy resulted in a marked decrease in the overall mean number of ischemic events and the average number of transient ischemic episodes (p <0.005). Amlodipine substantially reduced the number of ischemic events among all patients during the single-blind phase, with further significant reductions recorded among patients who remained on amlodipine during double-blind therapy, but the number of ischemic events increased almost to baseline levels in patients switched to placebo during double-blind therapy (p = 0.01 by analysis of variance).

Pharmacologic effects of calcium channel blockers on restenosis

The understanding and control of the healing process after percutaneous transluminal coronary angioplasty (PTCA) and of the pathogenesis of restenosis are incomplete. To date, only stent implantation has been shown to successfully reduce the rate of restenosis. Calcium channel blockers have positive effects on a number of processes that may be associated with restenosis, including reduction of platelet aggregation, minimization of vasospasm, and inhibition of mitogens. Clinical trials have therefore been performed to assess the effect of calcium channel blockers on restenosis and ischemia. A meta-analysis of five restenosis trials investigating calcium channel blockers demonstrated a 30% reduction in the risk for restenosis. The Coronary Angioplasty Amlodipine Restenosis Study (CAPARES) is therefore assessing the effect of amlodipine, a long-acting, third-generation calcium channel blocker in angioplasty patients. Therapy (amlodipine 5 mg with a forced titration to 10 mg once daily, or placebo), is begun 2 weeks before angioplasty and is continued for 4 months after the procedure. The rationale of CAPARES is that amlodipine may offer anti-ischemic protection before, during, and after angioplasty, may have more beneficial effects on restenosis and various clinical end points than calcium channel blockers used in previous trials, and may improve the long-term outcome of PTCA therapy.

Analysis of arrhythmias in the Circadian Antiischemia Program in Europe (CAPE) study

The aim of this study was to analyze whether, in patients with long-standing (>4 years) coronary artery disease (CAD), the addition of the long-acting calcium channel blocker (CCB) amlodipine to conventional treatment [beta-blockers (BBLs) and nitrates] during anginal attacks would have a proarrhythmic effect. This was tested by analyzing data from patients who had taken part in the Circadian Anti-ischemia Program in Europe (CAPE) trial. After a 2-week, single-blind, run-in period (Phase 1), patients were randomized to amlodipine, 5 mg/day (first 4 weeks) and 10 mg/day (second 4 weeks), or placebo for 8 weeks (Phase 2). The 48-h Holter data were analyzed for 167 amlodipine-treated patients and 83 placebo patients based on a 2:1 randomization scheme. Sixty-three per cent of amlodipine patients and 67% of placebo patients were receiving concomitant BBLs, and >90% had taken sublingual nitrates during anginal attacks, as basic antiischemic therapy. After 7 weeks of therapy, when 48-h Holter monitoring was repeated, there were no significant changes in the frequency of ventricular arrhythmias in the placebo or amlodipine groups for all patients or subgroups of patients with or without BBLs. Also, between-group comparisons showed no significant differences in arrhythmias between amlodipine and placebo patients. In summary, amlodipine (5-10 mg/day) given to patients with severe, chronic CAD receiving conventional antiischemic therapy, did not produce any proarrhythmic effects.