Non beta-blocker therapies are infrequently used in patients experiencing angina after PCI

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Alexander Fanaroff

Data from the TRANSLATE-ACS (Treatment with adenosine diphosphate receptor inhibitor: longitude assessment of treatment of patterns and events after acute coronary syndrome), published in the Journal of the American Heart Association, indicate that nearly a third of patients who have undergone percutaneous coronary intervention (PCI) for a myocardial infarction experience angina at six weeks after discharge.

Furthermore, the results of the study show that such patients infrequently receive non beta-blocker antianginal medications.

Study authors Alexander C Fanaroff (Division of Cardiolgoy, Duke University, Durham, USA) and others report that, prior to their study, the typical management of angina after PCI for an acute myocardial infarction was unknown. Therefore, they reviewed data from TRANSLATE-ACS (involving 10,870 patients) to gain a better understanding of the proportion of patients that have angina following PCI and to review how such patients are managed.

According to the results of the study, 29% of patients had self-reported angina at six weeks post discharge. Of these, 92% received beta-blockers but only 23.3% received other antianginal medication. Fanaroff et al conclude: “Strategies that increase awareness of angina burden coupled with symptom-driven management permit patient-centric improvement in outcomes should be explored”. In this interview, Fanaroff spoke to Cardiovascular News about the data and its implications.

What do current US guidelines recommend regarding secondary prevention following an acute coronary syndrome?

Current US guidelines recommend that aspirin, a P2Y12 inhibitor, a high-intensity statin, a beta-blocker should be given to patients without contraindications. They also advise that selected patients should receive an ACE inhibitor (or an ARB) and an aldosterone antagonist. Additionally, short-acting nitrates are recommended at discharge for all patients, and calcium-channel blockers are recommended in patients with angina who are refractory to beta-blockers and nitrates.

The stable ischaemic heart disease guidelines offer more guidance for angina management. Beta-blockers are recommended for all patients, and calcium-channel blockers or long-acting nitrates are recommended in addition to beta-blockers in patients with angina despite beta-blocker therapy or if beta-blocker therapy is contraindicated. Ranolazine may be used as a substitute for beta-blockers when beta-blockers are ineffective or contraindicated or in addition to beta-blockers when beta- blockers are inefficient. Revascularisation is recommended in patients with continued unacceptable angina despite medical therapy.

Essentially, the two sets of guidelines for management of chronic stable angina following an acute coronary syndrome can be summarised as such: beta-blockers are indicated in all patients, with stepped addition of calcium-channel blockers, long-acting nitrates, and ranolazine recommended for patients with continued angina on beta-blockers, and revascularisation is reserved for patients with continued angina despite medical treatment.

Prior to your study, what was known about adherence to US guidelines post acute coronary syndrome?

In a previous analysis, long-acting calcium-channel blockers were prescribed to 12% of patients with angina following myocardial infarction and nitrates, including short-acting nitrates, were prescribed to 51%.

How do the findings of study compare with those of previous studies?

About 29% of patients had angina at six weeks post-discharge. To the best of our knowledge, the presence of angina at six weeks following discharge has not been reported by a previous study.

Nearly 10% (9.7%) of patients in our study had persistent angina at one year, defined as angina at both six weeks and one year. Overall, 17.5% of patients reported angina at one year. The proportion of patients with persistent angina over the year following myocardial infarction had not been previously reported, to our knowledge. The proportion of patients with angina at 12 months in previous analyses was about 20%, close to the proportion reporting angina in our study.

Why do you think so few patients were receiving non beta-blocker medication?

This is an interesting question, and our study does not really answer it. However, symptomatic treatment of angina requires that patients report their symptoms to physicians. Multiple studies have shown that patient-physician communication about angina is suboptimal, with patient and physician reports of angina frequency often differing and a substantial minority of patients with angina indicating that they did not discuss their symptoms with their physician.

Other potential reasons could be physicians’ failure to recognise the importance of treating angina or the effectiveness of available antianginal medications, cost/logistical barriers to obtaining antianginal medications (though calcium-channel blockers and long-acting nitrates are available in generic form), and treatment inertia.

Another factor, which is less relevant to our study, in which patients self-reported angina, is that patients need to recognise their angina symptoms before they can be treated. Also, patients may unwittingly become more sedentary as coronary disease progresses and fail to recognise that angina has limited their activity level.

Do you think fewer patients would have had angina at six weeks or at one year if more of them were receiving non beta-blocker medication?

Based on what we know about antianginal medications from randomised clinical trials, I think it is likely that fewer patients would have had angina if more were receiving non beta-blocker antianginal medications. However, our study does not specifically address that question.

What are the key implications of your study?

The key implications are that angina following hospital discharge is frequent in patients that undergo PCI for myocardial infarction, that angina persists in roughly 30% of patients that have it immediately following hospital discharge, and that antianginal medications are used infrequently even in patients with severe or persistent angina following PCI for myocardial infarction. Strategies to enhance patient-provider communication regarding angina symptoms are needed and should be developed and tested.


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