Angiotensin II receptor antagonists in acute coronary syndromes

Prognostic impact of secondary prevention medical therapy following myocardial infarction with non-obstructive coronary arteries: a Bayesian and frequentist meta-analysis

AIMS

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a clinical entity with several causes and pathophysiologic mechanisms. Secondary prevention with medical therapy used in patients with obstructive coronary artery disease has unclear benefits in MINOCA patients.

METHODS AND RESULTS

A literature search was conducted until 8 March 2022. Random-effect frequentist and hierarchical Bayesian meta-analyses were performed to assess the clinical impact of medical therapy [renin-angiotensin-aldosterone system (RAAS) inhibitors, statins, dual antiplatelet therapy (DAPT), β-blockers] in MINOCA patients. Outcomes of interest were all-cause mortality and major adverse cardiovascular events (MACE). A total of 12 663 MINOCA patients among five observational studies were analysed. The mean follow-up ranged from 12 to 90 months across studies. In frequentist meta-analysis, statins and β-blockers were associated with a lower risk of all-cause mortality [pooled adjusted hazard ratios (aHRs) 0.53 and 0.81, with 95% confidence intervals (CIs) (0.37-0.76) and (0.67-0.97), respectively]. Only RAAS inhibitors were associated with a lower risk of MACE [pooled aHR: 0.69, with 95% CI (0.53-0.90)]. Bayesian meta-analysis based on informative prior assumptions offered strong evidence only for the benefit of statins on decreasing the risk of all-cause death [Bayes factor (BF): 33.2] and moderate evidence for the benefit of RAAS inhibitors on decreasing the risk of MACE (BF: 9); assigning less informative prior distributions did not affect the results, yet it downgraded the level of evidence to anecdotal.

CONCLUSION

In this meta-analysis, statins and RAAS inhibitors were consistently associated with a lower risk of all-cause mortality and MACE, respectively, in patients with MINOCA. Neutral prognostic evidence was demonstrated for β-blockers and DAPT.

Adipose tissue and blood leukocytes ACE2 DNA methylation in obesity and after weight loss

BACKGROUND

Obesity was consistently associated with a poor prognosis in patients with COVID-19. Epigenetic mechanisms were proposed as the link between obesity and comorbidities risk.

AIM

To evaluate the methylation levels of angiotensin-converting enzyme 2 (ACE2) gene, the main entry receptor of SARS-CoV-2, in different depots of adipose tissue (AT) and leukocytes (PBMCs) in obesity and after weight loss therapy based on a very-low-calorie ketogenic diet (VLCKD), a balanced hypocaloric diet (HCD) or bariatric surgery (BS).

MATERIALS AND METHODS

DNA methylation levels of ACE2 were extracted from our data sets generated by the hybridization of subcutaneous (SAT) (n = 32) or visceral (VAT; n = 32) adipose tissue, and PBMCs (n = 34) samples in Infinium HumanMethylation450 BeadChips. Data were compared based on the degree of obesity and after 4-6 months of weight loss either by following a nutritional or surgical treatment and correlated with ACE2 transcript levels.

RESULTS

As compared with normal weight, VAT from patients with obesity showed higher ACE2 methylation levels. These differences were mirrored in PBMCs but not in SAT. The observed obesity-associated methylation of ACE2 was reversed after VLCKD and HCD but not after BS. Among the studied CpG sites, cg16734967 and cg21598868, located at the promoter, were the most affected and correlated with BMI. The observed DNA methylation pattern was inversely correlated with ACE2 expression.

CONCLUSION

Obesity-related VAT shows hypermethylation and downregulation of the ACE2 gene that is mirrored in PBMCs and is restored after nutritional weight reduction therapy. The results warrant the necessity to further evaluate its implication for COVID-19 pathogenesis.

Secondary Prevention Medical Therapy and Outcomes in Patients With Myocardial Infarction With Non-Obstructive Coronary Artery Disease

Background

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a heterogeneous entity with relevant long-term major cardiovascular events. Several trials have demonstrated that dual antiplatelet therapy (DAPT), β-blocker, renin-angiotensin-aldosterone system (RAAS) inhibitor and statin therapy improve the prognosis in patients with obstructive myocardial infarction (ob-MI). However, evidence on the best medical therapy for secondary prevention in MINOCA patients is lacking.

Purpose

To investigate the effects of secondary prevention treatments at discharge on mid-term outcomes in MINOCA.

Methods

Patients with acute myocardial infarction (MI) undergoing early coronary angiography between 2016 and 2018 were extracted from a clinical database. The diagnosis of MINOCA was made according to 2016 ESC MINOCA Position Paper criteria. Second-level diagnostic work-up including cardiac magnetic resonance was performed to exclude non-ischemic troponin elevation cause. The relationship between treatments and outcomes was evaluated by using Kaplan-Meier survival analysis and Cox regression models. All confirmed MINOCA were followed in our outpatient clinics. The primary end-points were all-cause mortality, re-hospitalization for MI and a composite outcome including all-cause mortality, hospitalization for MI and ischemic stroke (MACE).

Results

Out of 1,141 AMI who underwent coronary angiography, 134 were initially diagnosed as MINOCA. Patients with MINOCA were less likely to receive secondary prevention treatments than patients with obstructive coronary artery disease (CAD) MI (respectively, 42.1% vs 81.8% for DAPT; 75.5% vs 89.6% for β-blockers; 64.7% vs 80.3% for RAAS inhibitor and 63.9% vs 83% for statins). Based on the diagnostic work-up completed during the first month after discharge, a final sample of 88 patients had confirmed MINOCA. During an average follow-up of 19.35 ± 10.65 months, all-cause mortality occurred in 11 (12.5%) patients, recurrence of MI in 4 (4.5%), and MACE in 15 (17.0%) patients. Patients treated with RAAS inhibitors and statins had a significantly longer survival. On the contrary, no increase in survival was found in patients treated with β-blockers or DAPT. Cox multivariable analysis, including all secondary prevention drugs, showed that only RAAS inhibitors were associated with reduced all cause-mortality and MACE.

Conclusion

This prospective study suggests that RAAS inhibitor therapy provides mid-term beneficial effects on outcomes in MINOCA patients; in contrast, dual antiplatelet, β-blocker and statin therapy had no effects on mortality and MACE. These results should be considered preliminary and warrant confirmation from larger studies.

Early occurrence of drug intolerance as risk factor during follow-up in patients with acute coronary syndrome or coronary revascularization

Aims

The occurrence of drug intolerance (DI) after an acute coronary syndrome (ACS) or percutaneous coronary intervention (PCI) is an important reason for quitting treatment. Nevertheless, the association between DI and major cardiac and cerebrovascular events (MACCE) is poorly reported in the literature, therefore, we analysed potential relationship between DI and MACCE (a composite of ACS, PCI, heart failure, and stroke) during follow-up.

Methods and results

From 1 January 2014 to 31 December 2015, 891 consecutive patients after ACS or coronary revascularization were referred to cardiac rehabilitation (CR) programme and included in a dedicated registry where DI was analysed and treatment appropriately tailored. Three hundred and nine patients (34.7%) developed DI, 26.9% of them were female. Angiotensin-converting enzyme (ACE) inhibitors and statins were the most frequent drugs which caused DI, followed by beta-blockers and calcium channel blockers, in 13.1%, 12.8%, 7.5%, and 5.5% of patients, respectively. During a median follow-up of 18 (interquartile range 11-24) months after CR, MACCE occurred in 14.1% of patients with DI and 8.1% without DI (P = 0.007). At multivariable model, DI to 1 drug [odds ratio (OR) 1.8, 95% confidence interval (CI) 1.01-3.18; P = 0.043] or to 2 drugs (OR 2.56, 95% CI 1.27-5.17; P = 0.008) were independently associated to MACCE. Regarding the association of specific class of prognostic drugs to MACCE, only DI to ACE-inhibitors was independently associated with MACCE (OR 2.31, 95% CI 1.14-4.65; P = 0.019).

Conclusion

DI was frequently encountered in real-world clinical practice and was significantly associated with MACCE during follow-up. This study suggests that early occurrence of DI could be considered to be an adjunctive cardiovascular risk factor during secondary prevention.

Influence of antihypertensive drugs on aortic and coronary effects of Ang-(1-7) in pressure-overloaded rats

This study investigated the influence of antihypertensive drugs, such as angiotensin-converting enzyme inhibitors (ACEIs), AT1 receptor blockers (ARBs), voltage-gated L-type calcium channel blockers, and mineralocorticoid receptor antagonists (MRAs), on the effects of angiotensin-(1-7) [Ang-(1-7)] on aorta and coronary arteries from pressure-overloaded rats. Pressure overload was induced by abdominal aortic banding (AB). To evaluate the role of antihypertensive drugs on the effect of Ang-(1-7), AB male Wistar rats weighing 250–300 g were treated with vehicle or low doses (5 mg·kg^-1·day^-1, gavage) of losartan, captopril, amlodipine, or spironolactone. Isolated aortic rings and isolated perfused hearts under constant flow were used to evaluate the effect of Ang-(1-7) in thoracic aorta and coronary arteries, respectively. Ang-(1-7) induced a significant relaxation in the aorta of sham animals, but this effect was reduced in the aortas of AB rats. Chronic treatments with losartan, captopril or amlodipine, but not with spironolactone, restored the Ang-(1-7)-induced aorta relaxation in AB rats. The coronary vasodilatation evoked by Ang-(1-7) in sham rats was blunted in hypertrophic rats. Only the treatment with losartan restored the coronary vasodilatory effect of Ang-(1-7) in AB rat hearts. These data support a beneficial vascular effect of an association of Ang-(1-7) and some antihypertensive drugs. Thus, this association may have potential as a new therapeutic strategy for cardiovascular diseases.

Update on the role of angiotensin in the pathophysiology of coronary atherothrombosis

BACKGROUND

Coronary atherothrombosis due to atherosclerotic plaque rupture or erosion is frequently associated with acute coronary syndromes (ACS). Significant efforts have been made to elucidate the pathophysiological mechanisms underlying acute coronary events.

MATERIALS AND METHODS

This narrative review is based on the material searched for and obtained via PubMed up to August 2014. The search terms we used were as follows: 'angiotensin, acute coronary syndromes, acute myocardial infarction' in combination with 'atherosclerosis, vulnerability, clinical trial, ACE inhibitors, inflammation'.

RESULTS

Among several regulatory components, the renin-angiotensin system (RAS) was shown as a key pathway modulating coronary atherosclerotic plaque vulnerability. Indeed, these molecules are involved in all stages of atherogenesis. Classically, the RAS is composed by a series of enzymatic reactions leading to the angiotensin (Ang) II generation and activity. However, the knowledge of RAS has expanded and become more complex. The discovery of novel components and their functions has revealed additional pathways that contribute to or counterbalance the actions of Ang II. In this review, we discussed on recent findings concerning the role of different angiotensin peptides in the pathophysiology of ACS and coronary atherothrombosis, exploring the link between these molecules and atherosclerotic plaque vulnerability.

CONCLUSIONS

Treatments selectively targeting angiotensins (including Mas and AT2 agonists, ACE2 recombinant, or Ang-(1-7) and almandine in oral formulations) have been tested in animal studies or in small human subgroups, expanding the perspective in the ACS prevention. These novel strategies, especially in the counter-regulatory axis ACE2/Ang-(1-7)/Mas, might be promising to reduce plaque vulnerability and inflammation.

Reasons for discontinuation of recommended therapies according to the patients after acute coronary syndromes

BACKGROUND

The prescription of recommended medical therapies is a key factor to improve prognosis after acute coronary syndromes (ACS). However, reasons for cardiovascular therapies discontinuation after hospital discharge are poorly reported in previous studies.

METHODS

We enrolled 3055 consecutive patients hospitalized with a main diagnosis of ACS in four Swiss university hospitals with a prospective one-year follow-up. We assessed the self-reported use of recommended therapies and the reasons for medication discontinuation according to the patient interview performed at one-year follow-up.

RESULTS

3014 (99.3%) patients were discharged with aspirin, 2983 (98.4%) with statin, 2464 (81.2%) with beta-blocker, 2738 (90.3%) with ACE inhibitors/ARB and 2597 (100%) with P2Y12 inhibitors if treated with coronary stent. At the one-year follow-up, the discontinuation percentages were 2.9% for aspirin, 6.6% for statin, 11.6% for beta-blocker, 15.1% for ACE inhibitor/ARB and 17.8% for P2Y12 inhibitors. Most patients reported having discontinued their medication based on their physicians' decision: 64 (2.1%) for aspirin, 82 (2.7%) for statin, 212 (8.6%) for beta-blocker, 251 (9.1% for ACE inhibitor/ARB) and 293 (11.4%) for P2Y12 inhibitors, while side effect, perception that medication was unnecessary and medication costs were uncommon reported reasons (<2%) according to the patients.

CONCLUSIONS

Discontinuation of recommended therapies after ACS differs according the class of medication with the lowest percentages for aspirin. According to patients, most stopped their cardiovascular medication based on their physician's decision, while spontaneous discontinuation was infrequent.