Anti-Anginal and Metabolic Effects of Carvedilol and Atenolol in Patients with Stable Angina Pectoris: A Prospective, Randomized, Parallel, Open-Label Study

Allopurinol versus Trimetazidine for the Treatment of Angina: A Randomized Clinical Trial

BACKGROUND

Recently, it was demonstrated that allopurinol, a xanthine oxidase inhibitor, has cardiovascular and anti-ischaemic properties and may be a metabolic antianginal agent option.Objective: The objective of this study was to evaluate the antianginal effect of allopurinol as a third drug for patients with stable coronary artery disease (CAD).

METHODS

This was a randomized clinical trial between 2018 and 2020 including patients with CAD who maintained angina despite initial optimization with beta-blockers and calcium channel blockers. The individuals were randomized 1:1 to 300 mg of allopurinol twice daily or 35 mg of trimetazidine twice daily. The main outcome was the difference in the angina frequency domain of the Seattle Angina Questionnaire (SAQ-AF). A probability (p) value < 0.05 was considered statistically significant.

RESULTS

A hundred and eight patients were included in the randomization phase, with 54 (50%) in the allopurinol group and 54 (50%) in the trimetazidine group. Six (5.6%) individuals, 3 from each group, were lost to follow-up for the primary outcome. In the allopurinol and trimetazidine groups, the median SAQ-AF scores were 50 (30.0 to 70.0) and 50 (21.3 to 78.3), respectively. In both groups, the SAQ-AF score improved, but the median of the difference compared to baseline was lower in the allopurinol group (10 [0 to 30] versus 20 [10 to 40]; p < 0.001), as was the mean of the difference in the total SAQ score (12.8 ± 17.8 versus 21.2 ± 15.9; p = 0.014).

CONCLUSION

Both allopurinol and trimetazidine improved the control of angina symptoms; however, trimetazidine presented a greater gain compared to baseline. Brazilian Registry of Clinical Trials - Registration Number RBR-5kh98y.

The clinical value of β-blockers in patients with stable angina

Stable angina, one manifestation of chronic coronary syndrome (CCS), is characterised by intermittent episodes of insufficient blood supply to the myocardium, provoking symptoms of myocardial ischaemia, particularly chest pain. These attacks usually occur during exercise or stress. Anti-ischaemic drugs are the mainstay of pharmacologic management of CCS with symptoms of angina. β-blockers reduce heart rate and myocardial contractility, thus reducing myocardial oxygen consumption. These drugs have been shown to ameliorate the frequency of anginal attacks and to improve exercise capacity in these patients. Current management guidelines include β-blockers as a first-line management option for most patients with CCS and symptoms of myocardial ischaemia, alongside dihydropyridine calcium channel blockers (CCB). The presence of comorbid angina and heart failure is a strong indication for starting with a β-blocker. β-blockers are also useful in the management of angina symptoms accompanied by a high heart rate, hypertension (with or without a renin-angiotensin-aldosterone-system [RAS] blocker or CCB), or microvascular angina (with a RAS blocker and a statin). A β-blocker is not suitable for a patient with low heart rate (<50 bpm), although use of a β-blocker may be supported by a pacemaker if the β-blocker is strongly indicated) and should be used at a low dose only in patients with low blood pressure.

Do Clinical Outcomes and Quality of Life Differ by the Number of Antianginals for Stable Ischemic Heart Disease? Insights from the BARI 2D Trial

Medical therapy, including antianginal treatment, is the cornerstone in the management of stable ischemic heart disease (SIHD). However, it remains unclear whether combining antianginal agents provides benefits beyond monotherapy in terms of quality of life (QoL) and cardiovascular outcomes. We used data from the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial, which compared cardiovascular and QoL outcomes in patients with SIHD and diabetes mellitus randomized to revascularization with intensive medical therapy or intensive medical therapy alone. We categorized patients into 3 groups: ≥2 versus 1 versus 0 antianginals. We compared patient characteristics, QoL metrics, and cardiovascular end points at baseline and at 5 years, creating a multivariable model to adjust for key clinical confounders. Of 2,368 patients, 348 patients (14.7%) were on 0 antianginals, 1,020 patients (43.1%) were on 1 antianginal, and 1,000 patients (42.2%) were on ≥2 antianginals at baseline. The most common antianginal class was β blockers. At baseline, patients on 0 antianginals had better QoL metrics (self-health score, Duke activity status index, and energy rating) than patients on ≥2 antianginals. However, at the 1-year follow-up, patients taking only 1 antianginal showed greater QoL improvement than those taking 0 antianginal, without any incremental benefit in QoL metrics seen in patients taking ≥2 antianginal agents, even after adjusting for multiple covariates such as age, heart failure, diabetes control, and myocardial jeopardy index. Lastly, at the 5-year follow-up, after adjustment, there were no differences in all-cause mortality, major adverse cardiovascular events, or myocardial infarction between patients taking different numbers of antianginals. Adults on a single antianginal for SIHD and diabetes mellitus had similar or better improvements in QoL than those on 2 or more antianginal agents at 1 year of follow-up. These findings merit further research to better understand the impact of medical therapy intensity on QoL in patients with SIHD and associated co-morbidities.

Effectiveness of bisoprolol versus other β-blockers and other antihypertensive classes: a cohort study in the Clinical Practice Research Datalink

Aim: To compare blood pressure (BP) and safety outcomes in patients with hypertension initiating bisoprolol, versus other β-blockers, angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers, calcium channel blockers or diuretics. Materials & methods: New user cohort study. Patients initiating bisoprolol were matched with up to four patients, in each comparator cohort using propensity score. BP outcomes were compared using linear mixed models and safety outcomes using Cox proportional hazards. Results: Differences in average systolic and diastolic BP variation were ≤3 mmHg between bisoprolol versus the compared classes. No difference was observed in risk of diabetes, obesity or erectile dysfunction. An increased dyslipidemia risk was only observed versus diuretics (hazard ratio: 0.76; 98.75% CI: 0.58, 0.99). Conclusion: No differences in BP variation and safety outcomes.

Advancements in pharmacotherapy for angina

INTRODUCTION

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