Clinical practice. Chronic stable angina

Impact of self-management interventions on stable angina symptoms and health-related quality of life: a meta-analysis

Background

Chronic stable angina (CSA) has a major negative impact on health-related quality of life (HRQL) including poor general health status, psychological distress, and inability to self-manage.

Methods

We used meta-analysis to assess the effectiveness of self-management interventions for improving stable angina symptoms, HRQL and psychological well-being. Nine trials, involving 1,282 participants in total, were included. We used standard inverse-variance random-effects meta-analysis to combine the trials. Heterogeneity between trials was evaluated using chi-square tests for the tau-squared statistic and quantified using the I² statistic.

Results

There was significant improvement in the frequency of angina symptoms (Seattle Angina Questionnaire [SAQ], symptom diary) across trials, standardized mean difference (SMD): 0.30 (95% Confidence interval [CI] 0.14, 0.47), as well as reduction in the use of sublingual (SL) nitrates, SMD: -0.49 (95% CI -0.77, -0.20). Significant improvements for physical limitation (SAQ), SMD: 0.38 (95% CI 0.20, 0.55) and depression scores (Hospital Anxiety and Depression Scale), SMD: -1.38 (95% CI -2.46, -0.30) were also found. The impact of SM on anxiety was uncertain due to statistical heterogeneity across trials for this outcome, I² = 98%. SM did not improve other HRQL dimensions including angina stability, disease perception, and treatment satisfaction.

Conclusions

SM interventions significantly improve angina frequency and physical limitation; they also decrease the use of SL nitrates and improve depression in some cases. Further work is needed to make definitive conclusions about the impact of SM on cardiac-specific anxiety.

Recent insights into the treatment of stable CAD : FFR-guided PCI vs. medical therapy

Cornerstones in the treatment of coronary artery disease (CAD) are medical therapy and coronary revascularization. In acute settings (ST-elevation myocardial infarction and non-ST-elevation myocardial infarction), percutaneous coronary intervention (PCI) has proven to improve prognosis. The optimal treatment of stable CAD is subject to great controversy. By using fractional flow reserve to guide PCI, it is possible to stent only those lesions that induce myocardial ischemia. This review aims to reflect on the use of FFR-guided PCI in stable CAD.

Antagonist molecules in the treatment of angina

INTRODUCTION

Management of chronic angina has evolved dramatically in the last few decades with several options for pharmacotherapy outlined in various evidence-based guidelines.

AREAS COVERED

There is a growing list of drugs that are currently being investigated for treatment of chronic angina. These also include several herbal medications, which are now being scientifically evaluated as potential alternative or even adjunctive therapy for angina. Gene- and cell-based therapies have opened yet another avenue for management of chronic refractory angina in 'no-option' patients who are not candidates for either percutaneous or surgical revascularization and are on optimal medical therapy. An extensive review of literature using PUBMED, Cochrane database, clinical trial databases of the USA and European Union was done and summarized in this review. This review will attempt to discuss the traditional as well as novel therapeutic agents for angina.

EXPERT OPINION

Several pharmacological and non-pharmacological therapeutic options are now available for treatment and management of chronic refractory angina. Renewed interest in traditional therapies and cell- and gene-based modalities with targeted drug delivery systems will open the doors for personalized therapy for patients with chronic refractory angina.

Identification of independent risk factors for restenosis following bare-metal stent implantation: Role of bare-metal stents in the era of drug-eluting stents

In the era of drug-eluting stents (DESs), the ability of clinicians to predict which patients have a low risk of coronary restenosis following bare-metal stent (BMS) implantion is likely to be of benefit. The study population consisted of 2,711 patients who underwent BMS implantation in 3,770 lesions between 1995 and 2004. With clinical and 6 month follow-up angiographic data, we retrospectively sought to identify the independent risk predictors of restenosis, applied a previously proposed prediction model and assessed the characteristics of patients with a low likelihood of coronary restenosis within 6 months of BMS implantation. A 6-month follow-up coronary angiography was performed in 65.0% of the patients who had undergone the BMS implantation and the rate of restenosis was 26.6%. Using multivariate analysis, diabetes [odds ratio (OR), 1.294; 95% confidence interval (CI), 1.094–1.483; P=0.005], current smoking (OR, 1.294; 95% CI, 1.094–1.483; P=0.002), a reference vessel diameter of <3.25 mm (OR, 1.238; 95% CI, 1.021–1.501; P<0.001), a lesion length of >30 mm (OR, 1.645; 95% CI, 1.336–2.026; P<0.001), ostial lesion (OR, 1.858; 95% CI, 1.437–2.402; P<0.001), post-stenting minimal luminal diameter (OR, 0.576; 95% CI, 0.484–0.685; P<0.001) and bifurcation lesion (OR, 1.353; 95% CI, 1.070–1.711; P=0.012) were identified as significant independent predictors of restenosis. However, the accuracy of the prediction obtained with the current model, which used the clinical and angiographic variables correlated with the risk of restenosis, was poor. Various clinical and angiographic independent risk variables were revealed to be correlated with the risk of restenosis following BMS implantation in the present large dataset. Certain groups of patients with a relatively low risk of restenosis may be considered for BMS implantation as an alternative to DESs. However, the prediction models used at present are incomplete and further studies are required.

Pharmacokinetic comparison of the vasorelaxant compound ferulic acid following the administration of Guanxin II to healthy volunteers and patients with angina pectoris

Coronary heart disease (CHD) is the leading cause of mortality worldwide. The Chinese medicinal formula Guanxin II has been shown to have a favorable effect in the attenuation of angina. The aim of this study was to compare the pharmacokinetics of ferulic acid (FA), which is a vasorelaxant compound present in Guanxin II, in healthy volunteers and patients with angina pectoris following the administration of Guanxin II. Ex vivo experiments were performed in order to investigate the vasorelaxant effect of FA on the human internal mammary artery (IMA) to provide evidence that it is a bioactive component of Guanxin II. Following the oral administration of Guanxin II, the FA levels in the serum were quantified by a simple and rapid high-performance liquid chromatography (HPLC) method. Treatment with FA (10⁻⁸−10⁻³ M) caused a concentration-dependent relaxation of endothelial IMA rings following precontraction with KCl. Statistically significant differences were identified between the pharmaco-kinetic parameters C_max, t_1/2α, t_1/2β and t_1/2Ka of the healthy volunteers and the patients with angina pectoris following the oral administration of Guanxin II. FA is a bioactive compound absorbed from Guanxin II that attenuates angina pectoris, a condition that may modify the pharmacokinetics of FA. Not only do the pharmacokinetic parameters direct the clinical use of Guanxin II, but they may also be useful for exploring the pathology of angina pectoris.

Anti-anginal and anti-ischemic effects of late sodium current inhibition

The effective treatment of coronary artery disease targets two distinct goals, controlling symptomatic angina and decreasing the adverse events associated with ischemia. Traditional anti-anginal and anti-ischemic drugs function by altering the determinants of myocardial oxygen supply or demand, usually by altering loading conditions, changing the heart rate, or impacting contractility. Blockade of the late inward sodium current, late I(Na), offers another target for the treatment of ischemia. Blockade of late I(Na) reduces the sodium and calcium overload that follows ischemia. This improves myocardial relaxation and reduces left ventricular diastolic stiffness, in turn enhancing myocardial contractility and perfusion. Ranolazine, a late I(Na) inhibitor, has been shown to provide both anti-anginal and anti-ischemic benefits without significant alterations in the heart rate and blood pressure in patients with stable coronary artery disease. When evaluated in patients with acute coronary syndrome, ranolazine has been shown to decrease recurrent ischemia, but not significantly reduce the risk of death or myocardial infarction. This review will address the rationale that inhibition of the late sodium current is beneficial in reducing cardiac dysfunction during ischemia, and discuss the clinical studies supporting the use of ranolazine for its anti-anginal and anti-ischemic effects.

Perioperative cardioprotection

Although anaesthesia itself is now very safe, perioperative cardiac complications during non-cardiovascular surgery are a major cause of morbidity and mortality, because of the increasingly high underlying prevalence of cardiovascular disease. Fortunately, although there is no "magic bullet", pharmacological intervention can reduce the risk. In particular, current evidence strongly supports the use of aspirin and statins. Beta blockers may also be beneficial in higher risk groups but need to be titrated to effect, and their use requires careful consideration because of adverse effects in these patients.

Obstructive coronary atherosclerosis and ischemic heart disease: an elusive link!

In the current pathophysiological model of chronic ischemic heart disease (IHD), myocardial ischemia and exertional angina are caused by obstructive atherosclerotic plaque, and the clinical management of IHD is centered on the identification and removal of the stenosis. Although this approach has been in place for years, several lines of evidence, including poor prognostic impact, suggest that this direct relationship may present an oversimplified view of IHD. Indeed, a large number of studies have found that IHD can occur in the presence or absence of obstructive coronary artery disease and that atherosclerosis is just 1 element in a complex multifactorial pathophysiological process that includes inflammation, microvascular coronary dysfunction, endothelial dysfunction, thrombosis, and angiogenesis. Furthermore, the high recurrence rates underscore the fact that removing stenosis in patients with stable IHD does not address the underlying pathological mechanisms that lead to the progression of nonculprit lesions. The model proposed herein shifts the focus away from obstructive epicardial coronary atherosclerosis and centers it on the microvasculature and myocardial cell where the ischemia is taking place. If the myocardial cell is placed at the center of the model, all the potential pathological inputs can be considered, and strategies that protect the cardiomyocytes from ischemic damage, regardless of the causative mechanism, can be developed.

A meta-analysis of randomized controlled trials comparing percutaneous coronary intervention with medical therapy in stable angina pectoris

There continues to remain uncertainty regarding the effect of percutaneous coronary intervention (PCI) vs medical therapy in patients with stable angina. We therefore performed a systematic review and study-level meta-analysis of randomized controlled trials of patients with stable angina comparing PCI vs medical therapy for each of the following individual outcomes: all-cause mortality, cardiovascular (CV) mortality, myocardial infarction (MI), and angina relief. We used 8 strategies to identify eligible trials including bibliographic database searches of MEDLINE, PubMed, EMBASE, and the Cochrane Controlled Trials Registry until November 2011. Two independent reviewers undertook decisions about study eligibility and data abstraction. Data were pooled using a random effects model. Ten prospective randomized controlled trials fulfilled our eligibility criteria and they included a total of 6752 patients. We did not detect differences between PCI vs medical therapy for all-cause mortality (663 events; relative risk [RR], 0.97 [confidence interval (CI), 0.84-1.12]; I(2) = 0%), CV mortality (214 events; RR, 0.91 [CI, 0.70-1.17]; I(2) = 0%), MI (472 events; RR, 1.09 [CI, 0.92-1.29]; I(2) = 0%), or angina relief at the end of follow-up (2016 events; RR, 1.10 [CI, 0.97-1.26]; I(2)=85%). PCI was not associated with reductions in all-cause or CV mortality, MI, or angina relief. Considering the cost implication and the lack of clear clinical benefit, these findings continue to support existing clinical practice guidelines that medical therapy be considered the most appropriate initial clinical management for patients with stable angina.

Patients with unstable angina pectoris show an increased frequency of the Fc gamma RIIa R131 allele

Patients with Systemic Lupus Erythematosus (SLE) carry an increased risk for the development of coronary artery disease (CAD). The R131 allele of the Fc gamma receptor IIa (FcγRIIa) is associated with SLE incidence and disease severity but also with CAD. Compared to stable angina pectoris (SAP) the unstable angina (UAP), as a manifestation of destabilizing CAD, is associated with increased risk of persistent instability, myocardial infarction, and death. Identification of clinically relevant determinants for unstable angina promises reduction of UAP-associated mortality in patients with SLE. We conducted a clinical study among 553 consecutive patients with stable angina pectoris (n = 330) and unstable angina pectoris (n = 223). All patients were genotyped for a frequent functional variant at position 131 of the mature FcγRIIa. UAP, but not SAP was significantly associated with the R/R131 genotype (P < 0.001). In troponin-negative patients with angina carrying the R/R131 genotype the odds ratio for suffering from UAP was 4.02 (95% confidence interval, 2.52-6.41) compared to those with non-R/R131 genotypes. In a multivariable analysis, the R/R131 genotype independently predicted the risk for development of UAP in a model adjusted for classical atherogenic risk factors. Our data imply that risk stratification of SLE- and other high risk patients with troponin-negative angina could be significantly improved by FcγRIIa genotyping.

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

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

Clinical Experience with Ranolazine in a Veteran Population with Chronic Stable Angina

BACKGROUND:

Efficacy of ranolazine in the treatment of chronic stable angina (CSA) has been established; however, pivotal trials did not require the optimization of conventional antianginal drug therapy (CADT) prior to use in a veteran population.

OBJECTIVE:

To determine whether ranolazine, when added to optimized doses of CADT, improves angina in a veteran population with CSA and refractory symptoms.

METHODS:

In an observational retrospective study, 35 patients prescribed ranolazine and having a baseline Seattle Angina Questionnaire (SAQ) administered at a Veterans Affairs medical center in Gainesville, FL, were evaluated. Patients who were prescribed ranolazine by a provider from outside the institution and did not obtain a baseline SAQ were excluded. The primary outcome measure was the change in SAQ scores from baseline to 1 and 3 months after initiation of ranolazine treatment. Secondary measures included clinically significant QTc interval prolongation (>500 msec or an increase of at least 60 msec from baseline), adverse drug reactions, discontinuation rates, and drug-drug interactions.

RESULTS:

The addition of ranolazine to optimized CADT was associated with improvement in all dimensions of the SAQ scores at 1 and 3 months compared to baseline scores (p < 0.001 for all dimensions). Mean changes in SAQ dimension scores at 1 and 3 months, respectively, were as follows: physical limitation, +9.86 and +11.94; angina stability, +39.29 and +32.69; angina frequency, +26.79 and +25.38; treatment satisfaction, +11.38 and +10.66; and disease perception, +16.85 and +18.59. Improvments in all dimensions, except treatment satisfaction, were clinically significant as defined by set criteria. Of the 7 patients whose ranolazine dosages were increased to 1000 mg twice daily, only 2 patients were able to maintain treatment at that dosage.

CONCLUSIONS:

Ranolazine added to optimized doses of CADT demonstrated an improvement in angina symptoms when given to a veteran population with persistent CSA.

The role of multi-slice computed tomography in stable angina management: a current perspective

Contrast-enhanced CT coronary angiography (CTCA) has evolved as a reliable alternative imaging modality technique and may be the preferred initial diagnostic test in patients with stable angina with intermediate pre-test probability of CAD. However, because CTCA is moderately predictive for indicating the functional significance of a lesion, the combination of anatomic and functional imaging will become increasingly important. The technology will continue to improve with better spatial and temporal resolution at low radiation exposure, and CTCA may eventually replace invasive coronary angiography. The establishment of the precise role of CTCA in the diagnosis and management of patients with stable angina requires high-quality randomised study designs with clinical outcomes as a primary outcome.

Medical therapy versus myocardial revascularization in chronic coronary syndrome and stable angina

Coronary artery disease is a leading cause of death in the United States. Angina is encountered frequently in clinical practice. Effective management of patients with coronary artery disease and stable angina should consist of therapy aimed at symptom control and reduction of adverse clinical outcomes. Therapeutic options for angina include antianginal drugs: nitrates, beta-blockers, calcium channel blockers, ranolazine, and myocardial revascularization. Recent trials have shown that although revascularization is slightly better in controlling symptoms, optimal medical therapy that includes aggressive risk factor modification is equally effective in reducing the risk of future coronary events and death. On the basis of the available data, it seems appropriate to prescribe optimal medical therapy in most patients with coronary artery disease and stable angina, and reserve myocardial revascularization for selected patients with disabling symptoms despite optimal medical therapy.

Regulatory systems for hypoxia-inducible gene expression in ischemic heart disease gene therapy

Ischemic heart diseases are caused by narrowed coronary arteries that decrease the blood supply to the myocardium. In the ischemic myocardium, hypoxia-responsive genes are up-regulated by hypoxia-inducible factor-1 (HIF-1). Gene therapy for ischemic heart diseases uses genes encoding angiogenic growth factors and anti-apoptotic proteins as therapeutic genes. These genes increase blood supply into the myocardium by angiogenesis and protect cardiomyocytes from cell death. However, non-specific expression of these genes in normal tissues may be harmful, since growth factors and anti-apoptotic proteins may induce tumor growth. Therefore, tight gene regulation is required to limit gene expression to ischemic tissues, to avoid unwanted side effects. For this purpose, various gene expression strategies have been developed for ischemic-specific gene expression. Transcriptional, post-transcriptional, and post-translational regulatory strategies have been developed and evaluated in ischemic heart disease animal models. The regulatory systems can limit therapeutic gene expression to ischemic tissues and increase the efficiency of gene therapy. In this review, recent progresses in ischemic-specific gene expression systems are presented, and their applications to ischemic heart diseases are discussed.

Threshold haemoglobin levels and the prognosis of stable coronary disease: two new cohorts and a systematic review and meta-analysis

BACKGROUND

Low haemoglobin concentration has been associated with adverse prognosis in patients with angina and myocardial infarction (MI), but the strength and shape of the association and the presence of any threshold has not been precisely evaluated.

METHODS AND FINDINGS

A retrospective cohort study was carried out using the UK General Practice Research Database. 20,131 people with a new diagnosis of stable angina and no previous acute coronary syndrome, and 14,171 people with first MI who survived for at least 7 days were followed up for a mean of 3.2 years. Using semi-parametric Cox regression and multiple adjustment, there was evidence of threshold haemoglobin values below which mortality increased in a graded continuous fashion. For men with MI, the threshold value was 13.5 g/dl (95% confidence interval [CI] 13.2-13.9); the 29.5% of patients with haemoglobin below this threshold had an associated hazard ratio for mortality of 2.00 (95% CI 1.76-2.29) compared to those with haemoglobin values in the lowest risk range. Women tended to have lower threshold haemoglobin values (e.g, for MI 12.8 g/dl; 95% CI 12.1-13.5) but the shape and strength of association did not differ between the genders, nor between patients with angina and MI. We did a systematic review and meta-analysis that identified ten previously published studies, reporting a total of only 1,127 endpoints, but none evaluated thresholds of risk.

CONCLUSIONS

There is an association between low haemoglobin concentration and increased mortality. A large proportion of patients with coronary disease have haemoglobin concentrations below the thresholds of risk defined here. Intervention trials would clarify whether increasing the haemoglobin concentration reduces mortality.

Long-term prognosis in stable angina; medical treatment or coronary revascularization in patients younger than 70 years?

BACKGROUND

Literature on the appropriateness of coronary revascularization in chronic angina is still scanty. The study aimed to compare long-term effects of revascularization with those of medical therapy in stable angina.

METHODS

In an observational single center study, we assessed 10 year follow-up of 1442 consecutive patients with chronic angina, at least one coronary vessel disease, no previous myocardial infarction, screened for inducible ischemia. Patients>70 years were excluded. The event-free probabilities were estimated by Kaplan-Meier curves; all cause death, cardiac death, non-fatal myocardial infarction were the considered end points.

RESULTS

Age was 56±8 yrs. Global left ventricular function was preserved in all. Myocardial ischemia was documented in 1190 patients. Coronary disease was more severe in patients with inducible ischemia as compared to those with negative stress test (p<0.001); 868 patients underwent one revascularization procedure, 511 coronary angioplasty. Median follow-up was 106 months; 13% all cause deaths, 8% cardiac deaths, 6% non-fatal myocardial infarction were registered. When provocative test was negative revascularization did not improve survival (1% per year mortality irrespective of type of treatment). Conversely survival was significantly improved by revascularization when ischemia was documented (0.7% vs 1.8% per year mortality for revascularization vs medical therapy, p<0.05). Incidence of non-fatal myocardial infarction was low and similar in both groups.

CONCLUSION

In low-risk chronic angina coronary revascularization does not improve long-term prognosis unless inducible myocardial ischemia is present. This suggests considering coronary revascularization as an effective tool in treating coronary artery disease only when myocardial ischemia has been documented.

A functional polymorphism in renalase (Glu37Asp) is associated with cardiac hypertrophy, dysfunction, and ischemia: data from the heart and soul study

BACKGROUND

Renalase is a soluble enzyme that metabolizes circulating catecholamines. A common missense polymorphism in the flavin-adenine dinucleotide-binding domain of human renalase (Glu37Asp) has recently been described. The association of this polymorphism with cardiac structure, function, and ischemia has not previously been reported.

METHODS

We genotyped the rs2296545 single-nucleotide polymorphism (Glu37Asp) in 590 Caucasian individuals and performed resting and stress echocardiography. Logistic regression was used to examine the associations of the Glu37Asp polymorphism (C allele) with cardiac hypertrophy (LV mass>100 g/m2), systolic dysfunction (LVEF<50%), diastolic dysfunction, poor treadmill exercise capacity (METS<5) and inducible ischemia.

RESULTS

Compared with the 406 participants who had GG or CG genotypes, the 184 participants with the CC genotype had increased odds of left ventricular hypertrophy (OR = 1.43; 95% CI 0.99-2.06), systolic dysfunction (OR = 1.72; 95% CI 1.01-2.94), diastolic dysfunction (OR = 1.75; 95% CI 1.05-2.93), poor exercise capacity (OR = 1.61; 95% CI 1.05-2.47), and inducible ischemia (OR = 1.49, 95% CI 0.99-2.24). The Glu37Asp (CC genotype) caused a 24-fold decrease in affinity for NADH and a 2.3-fold reduction in maximal renalase enzymatic activity.

CONCLUSIONS

A functional missense polymorphism in renalase (Glu37Asp) is associated with cardiac hypertrophy, ventricular dysfunction, poor exercise capacity, and inducible ischemia in persons with stable coronary artery disease. Further studies investigating the therapeutic implications of this polymorphism should be considered.

Clinical Potential of Combined Organic Nitrate and Phosphodiesterase Type 5 Inhibitor in Treatment-Resistant Hypertension

NO donor drugs (eg, isosorbide mononitrate; ISMN) and phosphodiesterase 5 inhibitors (eg, sildenafil) have antihypertensive properties, and the combination can markedly reduce blood pressure (BP). The objective of this “proof-of-concept” study was to investigate the effect on BP of a combination of single oral doses of sildenafil (50 mg) and ISMN (10 mg) in patients with treatment-resistant hypertension. Six subjects with treatment-resistant hypertension were included, and their usual antihypertensive medication was continued during the study. Sildenafil alone, ISMN alone, and the combination all reduced brachial and central aortic BPs compared with placebo. The combination of sildenafil and ISMN produced the largest fall in BP (maximum brachial BP reduction of 26/18 mm Hg compared with placebo), without producing significant adverse effects. ISMN, alone and in combination with sildenafil, also reduced arterial wave reflection and central BP. In summary, in patients with treatment-resistant hypertension maintained on their usual antihypertensive treatment, sildenafil given alone and ISMN given alone both acutely reduced BP. There was additional BP reduction when these drugs were given in combination. In this therapeutically challenging group of patients, the combination of an NO donor drug and a phosphodiesterase 5 inhibitor may represent an effective treatment. Longer studies in larger numbers of patients are now justified.

Percutaneous coronary intervention in chronic stable angina

Although the therapeutic advantage of percutaneous coronary intervention in acute coronary syndromes have been proved in numerous studies, its position in the treatment of stable angina remains a controversial issue. The results of the recent studies did not lead into definite answers for the proper treatment of chronic coronary artery disease. The identification of the patients that will benefit from the interventional approach is necessary and is probably based on the proper screening for myocardial ischemia with noninvasive diagnostic techniques. In this review article, we mention the most recent studies for the treatment of chronic stable angina with respect to clinical outcome and economical consequences.

Enhanced external counterpulsation for chronic angina pectoris

BACKGROUND

Cardiovascular disease is a major cause of death in developed and developing countries. Refractory stable angina pectoris is, in general, inadequately responsive to conventional medical therapy.Enhanced external counterpulsation is a non-invasive treatment for patients with refractory angina and involves the placing of compressible cuffs around the calves and lower and upper thighs. These are inflated sequentially so that during early diastole they help propel blood back to the heart and when deflated at end of diastole allow the blood vessels to return to their normal state. It is claimed that enhanced external counterpulsation can help reduce aortic impedance and thereby alleviate some of the symptoms of angina.

OBJECTIVES

To assess the effects of enhanced external counterpulsation therapy in improving health outcomes for patients with chronic stable or refractory stable angina pectoris.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (2008, Issue 1), MEDLINE (1966 to February 2008), EMBASE (1980 to February 2008), LILACS via BIREME (to February 2008) and ISI Science Citation Index on Web of Science (to February 2008). No language restrictions were applied.

SELECTION CRITERIA

Randomized controlled trials and cluster-randomized trials comparing enhanced external counterpulsation therapy to sham treatment in adults, aged over 18 years, with chronic stable and stable refractory angina pectoris graded Canadian Cardiovascular Society Class III to IV at baseline.

DATA COLLECTION AND ANALYSIS

Two authors independently screened papers, extracted trial details and assessed risk of bias.

MAIN RESULTS

One trial (139 participants) was included in this review. Poor methodological quality, in terms of trial design and conduct, incompleteness in reporting of the review's primary outcome, limited follow up for the secondary outcomes and subsequent flawed statistical analysis, compromised the reliability of the reported data.

AUTHORS' CONCLUSIONS

We found one relevant trial which failed to address the characteristics of interest satisfactorily, in terms of severity of angina, for the participants in this review. Participants with the most severe symptoms of angina were excluded, therefore the results of this study represent only a subsection of the broader population with the disorder, are not generalizable and provide inconclusive evidence for the effectiveness of enhanced external counterpulsation therapy for chronic angina pectoris.

Guanxin II (II) for the management of coronary heart disease

This article presents an integrated overview of Guanxin II (II) regarding its quality control, pharmacokinetics, pharmacology, clinical studies, adverse events, dosage and administration, and its pharmacoeconomic assessment. It has been demonstrated that Guanxin II has beneficial effects on coronary heart disease (CHD). The underlying mechanism was proved to be its anti-ischemic, anti-apoptotic, antioxidative, antiplatelet and anti-inflammatory effects, and so on. Tanshinol, hydroxysafflor yellow A and ferulic acid might be responsible for the cardioprotective effect of Guanxin II. In terms of acquisition cost, Guanxin II is cheaper than other drugs currently available for CHD. Guanxin II is safe, cheap, and effective in the management of CHD. However, the mechanism of its cardioprotective effects has not been completely understood because of limitations in the research methodologies of Chinese medicine. Further work should be carried out with single components such as tanshinol, hydroxysafflor yellow A and ferulic acid, using modern biochemical and molecular methods.

Psychosocial modulators of angina response to myocardial ischemia

BACKGROUND

Although angina is often caused by atherosclerotic obstruction of the coronary arteries, patients with similar amounts of myocardial ischemia may vary widely in their symptoms. We sought to compare clinical and psychosocial characteristics associated with more frequent angina after adjusting for the amount of inducible ischemia.

METHODS AND RESULTS

From 2004 to 2006, 788 consecutive patients undergoing single-photon emission computed tomography stress perfusion imaging at 2 Seattle hospitals were assessed for their frequency of angina over the previous 4 weeks with the Seattle Angina Questionnaire and for a broad range of psychosocial characteristics. Among patients with demonstrable ischemia on single-photon emission computed tomography (summed difference score >or=2; n=191), angina frequency was categorized as none (Seattle Angina Questionnaire score=100; n=68), monthly (score=61 to 99; n=66), and weekly or daily (score=0 to 60; n=57). Using multivariable ordinal logistic regression, increasing angina was significantly associated with a history of coronary revascularization (odds ratio 2.24, 95% confidence interval 1.19 to 4.19), anxiety (odds ratio 4.72, 95% confidence interval 1.91 to 11.66), and depression (odds ratio 3.12, 95% confidence interval 1.45 to 6.69) after adjustment for the amount of inducible ischemia.

CONCLUSIONS

Among patients with a similar burden of inducible ischemia, a history of coronary revascularization and current anxiety and depressive symptoms were associated with more frequent angina. These results support the study of angina treatment strategies that aim to reduce psychosocial distress in conjunction with efforts to lessen myocardial ischemia.

Computed tomography coronary angiography vs. stress ECG in patients with stable angina

PURPOSE

This study compared the role of multislice computed tomography coronary angiography (MSCT-CA) and stress electrocardiography (ECG) in the diagnostic workup of patients with chronic chest pain.

MATERIALS AND METHODS

MSCT-CA was performed in 43 patients (31 men, 12 women, mean age 58.8+/-7.7 years) with stable angina after a routine diagnostic workup involving stress ECG and conventional CA. The following inclusion criteria were adopted: sinus rhythm and ability to hold breath for 12 s. Beta-blockers were administered in patients with heart rate>or=70 beats/minute. In order to identify or exclude patients with significant stenoses (>or=50% lumen), we determined posttest likelihood ratios of stress test and MSCT-CA separately and of MSCT-CA performed after the stress test.

RESULTS

The pretest probability of significant coronary artery disease (CAD) was 74%. Positive and negative likelihood ratios were 2.3 [95% confidence interval (CI) 1.0-5.3] and 0.3 (95% CI: 0.2-0.7) for the stress test and 10.0 (95% CI: 1.8-78.4) and 0.0 (95% CI: 0.0-infinity) for MSCT-CA, respectively. MSCT-CA increased the posttest probability of significant CAD after a negative stress test from 50% to 86% and after a positive stress test from 88% to 100%. MSCT-CA correctly detected all patients without CAD.

CONCLUSIONS

Noninvasive MSCT-CA is a potentially useful tool in the diagnostic workup of patients with stable angina owing to its capability to detect or exclude significant CAD.

A meta-analysis of 17 randomized trials of a percutaneous coronary intervention-based strategy in patients with stable coronary artery disease

OBJECTIVES

This study assessed the impact on long-term mortality of percutaneous coronary intervention (PCI) versus medical treatment in patients with symptoms or signs of myocardial ischemia but no acute coronary syndrome.

BACKGROUND

The impact of PCI on the long-term prognosis of patients with stable coronary artery disease has not been established.

METHODS

We identified 17 randomized trials comparing a PCI-based invasive treatment strategy with medical treatment in 7,513 patients with symptoms or signs of myocardial ischemia but no acute coronary syndrome. Of these patients, 3,675 were assigned to the PCI group and 3,838 to the medical treatment group. The primary end point was all-cause death. The length of follow-up was in the range between 12 and 122 months, 51 months on average.

RESULTS

In the PCI group, 271 patients died compared with 335 patients in the medical treatment group, which corresponds to a 20% reduction in the odds ratio (OR) of all-cause death (OR: 0.80; 95% confidence interval [CI]: 0.64 to 0.99, p = 0.263 for heterogeneity across the trials). Allocation to the PCI group was associated with a nonsignificant 26% reduction in the OR of cardiac death (OR: 0.74, 95% CI: 0.51 to 1.06). In the PCI group, 319 patients had a nonfatal myocardial infarction after randomization compared with 357 patients in the medical treatment group (OR: 0.90, 95% CI: 0.66 to 1.23).

CONCLUSIONS

These findings suggest that a PCI-based invasive strategy may improve long-term survival compared with a medical treatment-only strategy in patients with stable coronary artery disease.

Secondary prevention of coronary artery disease in urban Indian primary care

BACKGROUND

Although secondary prevention has the potential to substantially reduce the risk of coronary events, its impact depends on the extent to which it is applied in the community. Presently, there is no information on the frequency with which drugs recommended for secondary prevention of CAD are used in the setting of primary care in India or other developing countries. Such information could help focus attention of physicians on its importance.

METHOD

In a prospective epidemiologic survey, 134 primary care physicians from 50 randomly selected cities distributed throughout India identified outpatients with stable CAD and symptoms of angina. Demographic and clinical characteristics, together with their treatment were recorded on a standardized questionnaire.

RESULTS

In 406 patients, the number (%, 95% CI) receiving aspirin was, 335 (82.5, 78.2 to 86.2); b-blockers, 215 (53.0, 48.1 to 57.9); angiotensin converting enzyme inhibitors (ACEI), 63 (15.5, 12.0 to 19.0); and statins, 280 (69.0, 61.0 to 77.0). Hypertension was untreated in 125 patients (33.4, 28.6 to 38.2). Combination treatment with any two (of aspirin, b-blocker, statin, ACEI, or antihypertensive agent other than b-blocker and ACEI) was received by 249 patients (61.3, 51.3 to 71.3); and with any three by 21 (5.2, 3.0 to 7.3).

DISCUSSION

Secondary prevention is under utilized in Indian patents with CAD. Against the background of an emerging epidemic, physicians in primary care need to increase the use of widely available specific secondary preventive agents recommended by guidelines.

Traditional management of chronic stable angina

The clinical syndrome of chronic stable angina is an age-related condition that is one common manifestation of coronary artery disease (CAD). The presence of angina significantly affects quality of life when patients must limit their activities of daily living in an effort to prevent the occurrence of anginal attacks. In addition, patients are at risk for significant complications of CAD such as myocardial infarction, heart failure, stroke, and death. Therefore, treatment should focus not only on relief of symptoms and improvements in quality of life, but also on preventing disease progression and reducing the risk of complications from CAD. All patients should be instructed on the appropriate use of sublingual nitroglycerin for the immediate treatment of anginal episodes. Beta-blockers, calcium channel blockers, long-acting nitrate therapy, and ranolazine can prevent anginal symptoms. In addition, aggressive risk factor management, healthy lifestyle changes, antiplatelet agents such as aspirin, and angiotensin-converting enzyme inhibitors all should be used to prevent disease progression and occurrence of myocardial infarction or death. Many patients will be candidates for revascularization of the myocardium with either percutaneous coronary intervention or coronary artery bypass grafting for relief of symptoms as well as improvement in prognosis. Even after revascularization, patients may still require antianginal drug therapy. All patients undergoing revascularization should be guided to make appropriate lifestyle changes and to make concerted efforts to manage risk factors for CAD.

Prognostic value of plasma myeloperoxidase concentration in patients with stable coronary artery disease

BACKGROUND

There are no studies yet on the usefulness of myeloperoxidase (MPO) as a prognostic tool in patients with stable coronary artery disease (CAD).

METHODS

The study included 382 patients with clinical and angiographic confirmation of stable CAD. Blood samples for MPO measurement were taken before angiography. Myeloperoxidase was determined using an enzyme immunoassay. The primary end point of the study was all-cause mortality.

RESULTS

Patients were categorized into 2 groups: the high-MPO group included patients in the third tertile of MPO levels (>75.0 microg/L; 127 patients), and the low-MPO group included patients in the first (<52.6 microg/L) and second tertiles (52.6-75.0 microg/L) of MPO levels (255 patients). The median follow-up was 3.5 [3.3-4.8] years. There were 35 deaths (9.2%) during the follow-up. The MPO concentration was 60.1 [47.0; 83.8] microg/L in survivors and 72.7 [54.8; 105.1] microg/L in nonsurvivors (P = .06). There were 17 deaths in the high-MPO level and 18 deaths in the low-MPO group: Kaplan-Meier estimates of mortality were 18.3% and 10.5% with an odds ratio of 1.96 (95% confidence interval [1.02-3.76], P = .04). The Cox proportional hazards model adjusting for correlates of mortality showed that plasma MPO was not an independent correlate of mortality (hazard ratio 1.06, 95% confidence interval [0.71-1.59], P = .77 for 1 SD increase in the log variable).

CONCLUSION

Although elevated plasma MPO concentration is associated with a more advanced cardiovascular risk profile, plasma MPO does not predict mortality independent of other cardiovascular risk factors in patients with stable CAD.

Coronary artery spasm--clinical features, diagnosis, pathogenesis, and treatment

Coronary (artery) spasm plays an important role in the pathogenesis of ischemic heart disease, including stable angina, unstable angina, myocardial infarction, and sudden death. The prevalence of coronary spasm differs among populations, is higher in Japan and Korea than in the Western countries probably due to genetic as well as environmental factors. Coronary spasm occurs most often from midnight to early morning and is usually not induced by exercise in the daytime. The attacks of coronary spasm are associated with either ST segment elevation or depression, or negative U wave on ECG. Patients with multi-vessel coronary spasm may suffer from lethal arrhythmia, including advanced AV block, ventricular tachycardia or fibrillation, or even sudden death, and they are often resistant to conventional medical therapy including Ca-channel blockers (CCBs). Endothelial nitric oxide (NO) activity is reduced and markers of oxidative stress are elevated in patients with coronary spasm. Thrombogenesis is enhanced and plasma levels of hsCRP and P-selection are elevated in patients with coronary spasm. Thus, patients with coronary spasm have endothelial dysfunction and are suffering from a low-grade chronic inflammation. Polymorphisms of endothelial NO synthase, smoking, and low-grade inflammation are the most important risk factors for coronary spasm. Coronary spasm is a hyper-contraction of coronary smooth muscle triggered by an increase of intracellular Ca2+ in the presence of an increased Ca2+ sensitivity. It has been shown that RhoA/ROCK pathway is involved in Ca2+ sensitivity and that the reduced endothelial NO activity results in increased Ca2+ sensitivity through enhanced RhoA/ROCK pathway. Accordingly, it is possible that in addition to CCBs, RhoA/ROCK pathway blockers may prove to be useful for the treatment of coronary spasm.

The management of hypertension in ischaemic heart disease

PURPOSE OF REVIEW

Patients with hypertension and coronary artery disease are often inadequately treated. Blood pressure levels remain unacceptably high in about half of such patients. A significant shortfall exists between guidelines and practice in implementing evidence-based drug therapy.

RECENT FINDINGS

Recent trials underscore the importance of blood pressure reduction. The purported superiority of specific drug classes, notably angiotensin-converting enzyme inhibitors and beta-blockers, is increasingly debated. Conversely, the benefits of calcium channel blockers are increasingly recognized. Irrespective of differences, all three agents are frequently required to achieve blood pressure targets. Beyond blood pressure reduction, statin therapy is undoubtedly the single most important risk factor intervention. New studies suggest that intensive lipid lowering and greater reductions in low-density lipoprotein cholesterol will further reduce major cardiovascular events. Finally, the impact of smoking cessation, exercise, and diet is often underestimated.

SUMMARY

The prognosis for patients is critically dependent on reducing global cardiovascular risk by addressing all modifiable risk factors. The cornerstone of treatment remains blood pressure reduction, using agents with both antihypertensive and antianginal properties.

Perioperative use of statins in noncardiac surgery

BACKGROUND

Statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) can significantly decrease cardiovascular mortality and morbidity, irrespective of the patients' cholesterol status. This paper reviews the effects of perioperative statin therapy in patients undergoing noncardiac surgery.

METHOD

A systematic literature review was undertaken of all published literature on this subject using Medline and cross-referenced. All published relevant papers on the perioperative use of statins were used.

RESULTS

Perioperative statin therapy is associated with a lower perioperative morbidity and mortality in patients undergoing elective or emergency surgery. The effects are due to a combination of lipid-lowering and pleiotropic properties of statins.

CONCLUSION

Ideally a large scale multi-centre randomized controlled trial of perioperative statin therapy should be performed but this may be difficult to conduct since there is already overwhelming evidence in the literature to suggest perioperative cardiovascular protective properties. Statins may still be under-prescribed in surgical patients.