Prognostic impact of ß-blocker use in patients with stable coronary artery disease

Beta-Blockers in the Prevention and Treatment of Ischemic Heart Disease: Evidence and Clinical Practice

Coronary artery disease (CAD) is the most prevalent cardiovascular disease characterized by atherosclerotic plaque buildup that can lead to partial or full obstruction of blood flow in the coronary arteries. Treatment for CAD involves a combination of lifestyle changes, pharmacologic therapy, and modern revascularization procedures. Beta-adrenoceptor antagonists (or beta-blockers) have been widely used for decades as a key therapy for CAD. In this review, prior studies are examined to better understand beta-adrenoceptor antagonist use in patients with acute coronary syndrome, stable coronary heart disease, and in the perioperative setting. The evidence for the benefit of beta-blocker therapy is well established for patients with acute myocardial infarction, but it diminishes as the time from the index cardiac event elapses. The evidence for benefit in the perioperative setting is not strong.

Physical activity and risk of all-cause mortality in patients with stable angina pectoris: Effect modification by β-blocker treatment

Background

Physical activity (PA) influences sympathetic stimulation, platelet activation as well as vascular function, and has been associated with improved health outcomes in patients with coronary heart disease. β-blocker therapy reduces sympathetic activity and improves platelet and endothelial function. We investigated if β-blocker treatment modifies the association of self-reported PA with the risk of all-cause mortality.

Methods

A total of 2284 patients undergoing elective coronary angiography for suspected stable angina pectoris (SAP) were studied. Using Cox modeling, we examined associations between PA (categorized as 'sedentary/inactive', 'low', 'moderate', and 'high') and all-cause mortality according to β-blocker therapy.

Results

During a median follow-up of 10.3 years, 390 patients (17.1%) died. Higher PA was generally associated with a more favorable cardiovascular risk profile. Compared to the patients who were sedentary or inactive, the age and sex adjusted HRs (95% CI) for all-cause mortality were 0.89 (0.66-1.20), 0.73 (0.57-0.95) and 0.72 (0.55-0.95) in the low, moderate and high PA group, respectively. However, and notably, these risk estimates were 0.85 (0.60-1.20), 0.65 (0.47-0.89) and 0.58 (0.41-0.81) in β-blocker treated subjects vs. 1.00 (0.57-1.78), 0.96 (0.61-1.52) and 1.20 (0.74-1.95) in non-treated groups (P _interaction = 0.018). The results were essentially similar in the multivariable adjusted models.

Conclusions

In patients with suspected SAP, increased PA was associated with reduced mortality risk primarily in patients treated with β-blockers.

MEdical TReatment Optimization in cardiac rehabilitation (METRO study) : a French multicenter study

BACKGROUND

Cardiac rehabilitation (CR) is the right place to optimize the medical treatment in coronary artery disease (CAD) patients.

AIMS

To report the medical management in CAD patients during CR and evaluate the consequences.

METHODS

CAD patients who attended a CR program within less than three months of an acute coronary syndrome (ACS), a percutaneous coronary intervention (PCI), or a coronary artery bypass graft (CABG) were included in a prospective multicenter study. Medical treatments were analyzed at the beginning and at discharge of the CR stay. Results of exercise tests were compared between 4 groups. G1: unchanged medication, n=443, G2: beta-blockers or bradycardic agents adaptation n=199, G3: renin-angiotensin system (RAS) inhibitors adaptation, n=194, G4: both medications adaptation, n=164.

RESULTS

One thousand consecutive patients were included in 23 French CR centers (85.3% males; mean age 59.9 ± 11 years). The index event was ACS (68.5%), PCI (62.6%) and CABG (36.3%). During CR, we noted an adaptation for beta-blockers in 32.1%, in other bradycardic agents (ivabradine, verapamil, diltiazem, amiodarone) in 9.5%, and in RAS inhibitors in 36.3%. Patients of group 1 had an initial resting heart rate lower than in group 2 and 4, but at the final exercise testing, the range of the decrease was more important in group 2 and 4. The combination of physical training and therapeutic modifications resulted in similar exercise capacities in the four groups, from 5.2, 5.3, 5.4 and 5.2 MET (p=0.68), to 6.3, 6.5, 6.5 and 6.1 MET (p=0.44), respectively.

CONCLUSION

The METRO study showed that significant alteration in medical treatment during cardiac rehabilitation programs could take part in improving physical capacity.

β-blocker use and risk of all-cause mortality in patients with coronary heart disease: effect modification by serum vitamin A

AIMS 

Blockade of β-adrenoceptors reduces sympathetic nervous system activity and improves survival in patients with heart failure with reduced left ventricular ejection fraction (HFrEF); however, any improvement in longevity among patients with coronary heart disease (CHD) but without HFrEF remains uncertain. Vitamin A has been linked to the activation of tyrosine hydroxylase, the rate-limiting enzyme in the catecholamine synthesis pathway. We investigated if vitamin A status modified the association of β-blocker use with the risk of all-cause mortality.

METHODS AND RESULTS 

A total of 4118 patients undergoing elective coronary angiography for suspected stable angina pectoris, of whom the majority had normal left ventricular ejection fraction (LVEF) were studied. Hazard ratios (HRs) of all-cause mortality comparing treatment vs. non-treatment of β-blockers according to the tertiles of serum vitamin A were explored in Cox proportional hazards regression models. During a median follow-up of 10.3 years, 897 patients (21.8%) died. The overall LVEF was 65% and 283 (6.9%) had anamnestic HF. After multivariable adjustments for traditional risk factors, medical history, and drug therapies of cardiovascular disease, β-blocker treatment was inversely associated with the risk of all-cause mortality [HR : 0.84; 95% CI (confidence interval), 0.72-0.97]. However, the inverse association was generally stronger among patients in the upper serum vitamin A tertile (HR :0.66; 95% CI, 0.50-0.86; Pinteraction = 0.012), which remained present after excluding patients with LVEF < 40%.

CONCLUSION 

In patients with suspected CHD, β-blocker treatment was associated with improved survival primarily among patients with high serum vitamin A levels.

Treatment of stable ischaemic heart disease: the old and the new

Stable ischaemic heart disease is a frequent and very heterogeneous condition. Drug therapy is important, in these patients, for improving their prognosis and controlling their symptoms. The typical clinical manifestation of obstructive coronary disease is angina pectoris. This symptom can be improved by various classes of compounds, namely beta-blockers (BBs), calcium antagonist, and nitrates. More recently, ranolazine and ivabradine have been introduced. All these drugs have been proven to reduce significantly angina. On the other hand, there are no evidences supporting improvement in prognosis, besides for the use of BBs, in patients with previous myocardial infarction (MI) or systolic dysfunction. Besides drugs for symptoms control, these patients also receive antiplatelet drugs, specifically aspirin, and lipid lowering compounds such as statins. Furthermore, recent evidences supported the use of low doses direct anticoagulant, or a second antiplatelet agent in patients with previous MI. Similarly, a very low LDL cholesterol level, such as obtained with PCKS9 inhibitors, seems very beneficial in these patients. It is possible that in the near future a specific role for neo-angiogenesis factors and cellular therapies, could be proven, albeit, presently these treatments are not supported by solid evidences.

Pro-angiogenic Role of Danqi Pill Through Activating Fatty Acids Oxidation Pathway Against Coronary Artery Disease

Coronary artery disease (CAD) is one of the leading causes of deaths worldwide. Energy metabolism disorders, including a reduction in fatty acids oxidation and upregulation of glycolysis pathway, are involved in the process of CAD. Therapeutic angiogenesis has become a promising treatment for CAD. Traditional Chinese medicines, such as Danqi Pill (DQP), have been proven to be effective in treating CAD in China for many years. However, the pro-angiogenic effects of DQP based on fatty acids oxidation are still unknown and the mechanism is worthy of investigation. In this study, left anterior descending (LAD) coronary artery was ligated to induce the CAD models in vivo, and cardiac functions were examined using echocardiography. Human umbilical vein endothelial cells (HUVEC) were subjected to H₂O₂-induced oxidative stress in vitro. The effects of DQP on CAD rat models and in vitro HUVEC were detected. Our results showed that DQP had cardio-protective effects in rat model. The intensity of capillaries in the marginal area of infarction of the rat heart was increased remarkably in DQP group, and the expression of PPARα and VEGF-2 were increased. The key enzymes involved in the transportation and intake of fatty acids, including CPT1A and CD36, both increased. In H₂O₂-induced endothelial cells injury models, DQP also showed protective roles and promoted capillary-like tube formation. DQP up-regulated key enzymes in fatty acids oxidation in H₂O₂-treated HUVEC. In addition, inhibition of CPT1A compromised the pro-angiogenic effects of DQP. In conclusion, fatty acids oxidation axis PPARα-CD36-CPT1A was involved in the pro-angiogenic roles of DQP against CAD. Cardiac CPT1A may serve as a target in therapeutic angiogenesis in clinics.

Potential Effectiveness of Chinese Patent Medicine Tongxinluo Capsule for Secondary Prevention After Acute Myocardial Infarction: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Chinese patent medicine Tongxinluo capsule (TXL) is commonly used for cardio-cerebrovascular diseases. Previous research had demonstrated that TXL exhibited great clinical effects on the treatment of acute myocardial infarction (AMI), however there is a lack of systematic review. The purpose of this study was to evaluate the potential effectiveness and safety of TXL for secondary prevention in patients with AMI. Method: We searched 6 databases to identify relevant randomized controlled trials (RCTs) from inceptions to December 30, 2017. Two review authors independently assessed the methodological quality and analyzed data by the RevMan 5.3 software. The publication bias was assessed through funnel plot and Begg's test. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used for evaluating the quality of evidence. Results: We included 19 RCTs in this review and performed a meta-analysis based on 16 studies. There were statistical differences of TXL treatment group in reducing primary cardiovascular events (cardiac death [RR = 0.27, 95%CI: 0.08~0.95, I2 = 0%], recurrent myocardial reinfarction [RR = 0.38, 95%CI: 0.20~0.74, I2 = 0%], arrhythmia [RR = 0.44, 95%CI: 0.30~0.66, I2 = 0%], recurrent angina pectoris [RR = 0.34, 95%CI: 0.17~0.69, I2 = 0%]). TXL could improve cardiac function (LVEF [MD = 4.10, 95%CI: 3.95~4.25, I2 = 0%]), regulate blood lipid TC [MD = -0.66, 95%CI: -0.94 ~ -0.37, I2 = 74%], TG [MD = -0.38, 95%CI: -0.62 ~ -0.14, I2 = 70%], LDL-C[-0.40, 95%CI: -0.65 ~ -0.16, I2 = 88%), decrease the level of hs-CRP (4-week: MD = -0.78, 95%CI: -0.97 ~ -0.60, I2 = 20%; Over 4-week: MD = -1.36, 95%CI: -1.55 ~ -1.17, I2 = 20%). However, TXL has little effects on revascularization [RR = 0.45, 95%CI: 0.13~1.56, I2 = 0%], recurrent heart failure (RR = 0.83, 95%CI: 0.27~2.57, I2 = 0%), and HDL-C (MD = 0.14, 95%CI: 0.00 ~0.29, I2 = 73%). Furthermore, TXL treatment group was more prone to suffer gastrointestinal discomfort. Conclusion: Chinese patent medicine TXL seemed beneficial for secondary prevention after AMI. This potential benefit needs to be further assessed through more rigorous RCTs. Systematic review registration number in the PROSPERO register: CRD42017068417.

Therapeutic Angiogenesis of Chinese Herbal Medicines in Ischemic Heart Disease: A Review

Ischemic heart disease (IHD) is one of the primary causes of death around the world. Therapeutic angiogenesis is a promising innovative approach for treating IHD, improving cardiac function by promoting blood perfusion to the ischemic myocardium. This treatment is especially important for targeting patients that are unable to undergo angioplasty or bypass surgery. Chinese herbal medicines have been used for more than 2,500 years and they play an important role alongside contemporary medicines in China. Growing evidence in animal models show Chinese herbal medicines can provide therapeutic effect on IHD by targeting angiogenesis. Identifying the mechanism in which Chinese herbal medicines can promote angiogenesis in IHD is a major topic in the field of traditional Chinese medicine, and has the potential for advancing therapeutic treatment. This review summarizes the progression of research and highlights potential pro-angiogenic mechanisms of Chinese herbal medicines in IHD. In addition, an outline of the limitations of Chinese herbal medicines and challenges they face will be presented.

Long-term secondary prevention of acute myocardial infarction (SEPAT) - guidelines adherence and outcome

Background

A number of registry studies have reported suboptimal adherence to guidelines for cardiovascular prevention during the first year after acute myocardial infarction (AMI). However, only a few studies have addressed long-term secondary prevention after AMI. This study evaluates prevention guideline adherence and outcome of guideline-directed secondary prevention in patients surviving 2 years after AMI.

Methods

Patients aged 18–85 years at the time of their index AMI were consecutively identified from hospital discharge records between July 2010 and December 2011 in Gothenburg, Sweden. All patients who agreed to participate in the study (16.2%) were invited for a structured interview, physical examinations and laboratory analysis 2 years after AMI. Guideline-directed secondary preventive goals were defined as optimally controlled blood pressure, serum cholesterol, glucose, regular physical activity, smoking cessation and pharmacological treatment.

Results

The mean age of the study cohort (n = 200) at the index AMI was 63.0 ± 9.7 years, 79% were men. Only 3.5% of the cohort achieved all six guideline-directed secondary preventive goals 2 years after infarction. LDL < 1.8 mmol/L was achieved in 18.5% of the cohort, regular exercise in 45.5% and systolic blood pressure <140 mmHg in 57.0%. Anti-platelet therapy was used by 97% of the patients, beta-blockers by 83.0%, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers by 76.5% and statins by 88.5%. During follow-up, non-fatal adverse cardiovascular events (cardiac hospitalization, recurrent acute coronary syndrome, angina pectoris, new percutaneous coronary intervention, new onset of atrial fibrillation, post-infarct heart failure, pacemaker implantation, stroke/transient ischemic attack (TIA), cardiac surgery and cardiac arrest) occurred in 47% of the cohort and readmission due to cardiac causes in 30%.

Conclusions

Our data showed the failure of secondary prevention in our daily clinical practice and high rate of non-fatal adverse cardiovascular events 2 years after AMI.

Efficacy of β-blocker therapy for secondary prevention for patients undergoing coronary artery bypass grafting surgery

PURPOSE OF REVIEW

The efficacy and safety of β-blockers in the treatment of cardiovascular diseases, such as ischemic heart disease, cardiac arrhythmias, and heart failure, have been well established for decades. In this article, we review the current opinions on the application of β-blockers for secondary prevention in patients undergoing coronary artery bypass grafting (CABG) surgery.

RECENT FINDINGS

As the average age of patients treated surgically for coronary artery disease (CAD) is increasing, it is not uncommon to have candidates for CABG presenting with concomitant atrial fibrillation, heart failure or hypertension, most of which were caused by excessive activation of the adrenergic nervous system. In a recent decade, a number of national quality-improvement efforts using a variety of techniques have been made to increase the use of β-blocker therapy before or following the CABG. Results from recent large observational studies among patients with CAD showed that β-blockers were associated with a lower risk of cardiac events only among those with heart failure or recent myocardial infarction. However, the consistent use of β-blockers could benefit those with or without prior myocardial infarction who underwent CABG and discharged alive.

SUMMARY

In real-world clinical practice, β-blockers are effective and safe to control heart rate and symptoms in patients with CAD, especially for those concomitant with left ventricular systolic dysfunction or prior myocardial infarction. Current evidence supports the preoperative use of β-blocker therapy for patients undergoing CABG as a prevention of new-onset atrial fibrillation. It is reasonable to continue β-blockers as chronic therapy in all CABG patients without contraindications after hospital discharge. Further strategies should be developed to understand and improve discharge prescription of β-blockers and long-term patient adherence.

Association of β-blocker therapy with long-term clinical outcomes in patients with coronary chronic total occlusion

There are limited data regarding the efficacy of β-blockers for secondary prevention in patients with coronary chronic total occlusion (CTO). Therefore, we investigated the association of β-blocker therapy with long-term clinical outcomes in CTO patients. From March 2003 to February 2012, a total of 2024 CTO patients treated with either medical therapy alone or revascularization were enrolled in the study. We assessed 1596 patients with stable ischemic heart disease and divided them into the β-blocker group (n = 932) and the no-β-blocker group (n = 664). The primary outcome was all-cause death. The median follow-up duration was 3.9 (interquartile range: 2.0-6.2) years. All-cause death occurred in 11.6% patients in the β-blocker group and 13.6% patients in the no-β-blocker group (hazard ratio [HR]: 0.81, 95% confidence interval [CI]: 0.61-1.08; P = 0.15). In the propensity score-matched population (570 pairs), all-cause death occurred in 12.3% patients in the β-blocker group and 12.8% patients in the no-β-blocker group (HR: 0.93, 95% CI: 0.67-1.29; P = 0.66). In subgroup analysis, β-blocker therapy was associated with better outcome, in terms of all-cause death, in patients with CTO of the left anterior descending coronary artery and Synergy Between PCI with Taxus and Cardiac Surgery (SYNTAX) score ≥23 (P for interaction = 0.01 and 0.02, respectively). In conclusion, β-blocker therapy was not associated with favorable long-term clinical outcomes in stable CTO patients, regardless of treatment strategy. However, β-blocker therapy might be beneficial in a highly selective group of CTO patients with a high ischemic burden.

Practice Patterns for Outpatients With Stable Coronary Artery Disease: A Case Vignette-based Survey Among French Cardiologists

BACKGROUND

Although medical management of patients with coronary artery disease (CAD) is often based on scientific guidelines, a number of everyday clinical situations are not specifically covered by recommendations or the level of evidence is low. The aim of this study was to assess practice patterns regarding routine management of patients with stable CAD.

METHODS

A survey comprising six questions on two clinical scenarios regarding stable CAD management was sent to 345 cardiologists from the Nord-Pas-de-Calais Region (France). We first assessed practice patterns globally and then searched for associations with physician characteristics (age, gender, sub-specialty, and type of practice).

FINDINGS

The response rate was 92%. Regarding management of asymptomatic CAD, 86% of the cardiologists performed routine exercise testing, before which, 69% withdrew β-blockers. After a positive exercise test, 26% immediately performed coronary angiography and 67%, further imaging tests. In the absence of left ventricular dysfunction or history of myocardial infarction, routine β-blocker prescription for stable CAD was selected by 43%. When anticoagulation was needed for atrial fibrillation, 41% initiated direct oral anticoagulants rather than vitamin-K antagonists and 50% combined aspirin with anticoagulants. For recurrent stable angina in patients with known CAD, 24% performed coronary angiography directly, 49% requested a stress test, and 27% opted for medical therapy without further diagnostic testing. Age, gender of the cardiologist, academic environment, and practice of interventional cardiology were associated with certain management patterns.

INTERPRETATION

When not guided by high-level recommendations, practice patterns for routine clinical situations in stable CAD vary considerably. Future clinical trials should address these clinical interrogations.

Does Oral Beta-Blocker Therapy Improve Long-Term Survival in ST-Segment Elevation Myocardial Infarction With Preserved Systolic Function? A Meta-Analysis

BACKGROUND

The effect of oral beta-blocker therapy on long-term mortality in patients with ST-segment elevation myocardial infarction (STEMI) who are treated with primary percutaneous coronary intervention (PCI) and who have preserved left ventricular ejection fraction (LVEF) remains unclear.

METHODS

We searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials for studies evaluating the effect of oral beta-blocker therapy in patients with STEMI who underwent primary PCI and who had preserved LVEF. The primary outcome was all-cause mortality. Randomized controlled trials and the observational studies that reported an adjusted hazard ratio (or hazard ratio in the propensity score-matched patients) with follow-up duration equal to or more than 6 months were included. Pooled hazard ratio with 95% confidence interval (CI) was calculated using a random effect model.

RESULTS

No randomized controlled trials met the inclusion criteria. Seven observational studies totaling 10 857 patients met the inclusion criteria. Follow-up duration ranged from 6 months to 5.2 years. Preserved LVEF was defined as 40% in 4 studies and 50% in 3 studies. Based on the pooled estimate, oral beta-blocker therapy was associated with a reduction in all-cause mortality (combined hazard ratio 0.79, 95% CI 0.65-0.97).

CONCLUSION

This meta-analysis demonstrates that oral beta-blocker therapy is associated with decreased all-cause mortality in patients with STEMI who are treated with primary PCI and who have preserved LVEF. This supports the current American College of Cardiology Foundation/American Heart Association 2013 Guideline for the Management of STEMI.

Prognostic Significance of the Renal Resistive Index After Renal Artery Revascularization in the Context of Flash Pulmonary Edema

PURPOSE

To evaluate the prognostic value of the renal resistive index (Ri) after renal artery revascularization in the context of flash pulmonary edema.

METHODS

Between 2000 and 2008, 43 patients (mean age 72.1±10.9 years; 23 women) underwent renal artery angioplasty/stenting in the context of flash pulmonary edema. Intrarenal Ri was assessed using duplex ultrasound. The majority (97.7%) of patients had hypertension, and nearly half (46.5%) had diabetes mellitus. For this retrospective analysis, the patients were divided into 2 groups according to the median Ri (<0.8 and ≥0.8) of the population. A Cox proportional hazards model was used to identify predictors of all-cause mortality (primary endpoint) and rehospitalization for heart failure; the results are presented as the hazard ratio (HR) and 95% confidence interval (CI). The mean follow-up was 49.8±30.6 months.

RESULTS

There was no difference between the groups regarding clinical characteristics. A high Ri was associated with the risk of all-cause death (HR 2.54, 95% CI 1.15 to 5.60, p=0.021). This relationship was still statistically significant after adjustment for age, gender, diabetes, glomerular filtration rate, and treatment with a renin-angiotensin system inhibitor (HR 1.74, 95%CI 1.08 to 2.81, p=0.032). A high Ri was also associated with cardiovascular death in unadjusted and adjusted analyses. In contrast, a high Ri was not associated with the risk of rehospitalization for heart failure.

CONCLUSION

After renal artery revascularization for flash pulmonary edema, a high intrarenal Ri is independently associated with all-cause mortality. Determination of the intrarenal Ri after this procedure may be useful for identifying at-risk patients.

Prevalence and correlates of non-optimal secondary medical prevention in patients with stable coronary artery disease

BACKGROUND

In patients with coronary artery disease (CAD), non-optimal use of evidence-based medications is associated with an increased risk of adverse outcome.

AIMS

To assess the prevalence and correlates of non-optimal secondary medical prevention in patients with stable CAD.

METHODS

We included 4184 consecutive outpatients with stable CAD. Treatment at inclusion was classified as optimal/non-optimal regarding the four major classes of secondary prevention drugs: antithrombotics; statins; angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs); and beta-blockers. For each treatment, the prescription was considered non-optimal if the drug was missing despite a class IA indication according to international guidelines. To assess the information globally, non-optimal secondary prevention was defined as at least one major treatment missing.

RESULTS

The proportions of patients with non-optimal treatment were 0.7%, 7.8%, 12.9% and 10.3% for antithrombotics, statins, ACE inhibitors/ARBs and beta-blockers, respectively. Non-optimal secondary medical prevention was observed in 16.8% of cases. By multivariable analysis, the correlates of non-optimal secondary medical prevention were long time interval since last coronary event (P<0.0001), older age (P<0.0001), diabetes mellitus (P<0.0001), hypertension (P<0.0001), no history of myocardial infarction (P=0.001), no history of coronary revascularization (P=0.013) and low glomerular filtration rate (P=0.042).

CONCLUSIONS

Although most patients with stable CAD are receiving evidence-based medications according to guidelines, there remain subgroups at higher risk of non-optimal treatment. In particular, it might be feasible to improve prevention by focusing on patients in whom a long time has elapsed since the last coronary event.