Should stable coronary artery disease patients without angina receive anti-ischemic therapy ?

Should stable coronary artery disease patients without angina receive anti-ischemic therapy ?
Magdy Abdel Hamid , MD , FSCAI
Professor of Cardiovascular Medicine
Faculty of Medicine, Cairo University
Coronary artery disease (CAD) may be asymptomatic or cause angina pectoris ,myocardial infarction (MI) ,heart failure ,arrhythmias ,and sudden death . Silent ischemia is typically defined as objective evidence of myocardial ischemia in patients without symptoms related to that ischemia. In fact, asymptomatic (or silent) ST-segment depression during ambulatory electrocardiogram monitoring (AECG) occurs more often than symptomatic ST-segment depression in patients with CAD. In patients with medically managed CAD, the likelihood of death or MI during 7 years of follow-up was similar between patients with asymptomatic and those with symptomatic ST-segment depression with exercise Silent ischemia during AECG monitoring was a more powerful predictor of mortality than exercise duration, age, previous MI , hypertension, diabetes, or smoking history.
Should therapy in patients with stable CAD be guided by angina symptoms or by ischemia ? ,The goals of treatment of CAD aims to reduce risk of disease progression, prevention of acute coronary syndromes (ACS) and cardiovascular death ,in addition
to relieve symptoms and improve quality of life in patients with stable CAD.Silent myocardial ischemia is a major component of the total ischemic burden for patients with CAD. Management should aim to reduce or eliminate myocardial ischemia by risk factor modification, aggressive medical therapy and, if appropriate, myocardial revascularization .
Optimal management of CAD includes: (i) appropriate lifestyle, i.e.
no smoking, a healthy diet, weight control, and regular exercise; (ii) detection and treatment of diseases and conditions which increase the risk of atherosclerosis, in particular hypertension, diabetes, and hypercholesterolemia; (iii) regardless of LDL cholesterol levels, all patients with coronary artery disease should be taking an HMG-CoA reductase inhibitor or “statin” which has been shown to reduce progression of disease
.In addition , significant mortality benefits and reduction of ACS have been demonstrated in multiple trials, even in CAD patients with normal LDL levels .Statins have anti-inflammatory properties and plaque stabilization capabilities independent of LDL lowering. ; (iv) additional preventive therapy with aspirin, other anti-thrombotic agents, ACE-inhibitors, and ß- blockers in patients with known atherosclerosis .Every patient with documented CAD should be taking antiplatelet therapy, usually in the form of aspirin, for the prevention of ACS .Low dose aspirin (75 mg to 150 mg) has been shown to be equally effective as medium dose aspirin (162 mg to 325 mg) with less gastrointestinal bleeding complications. In addition, clopidogrel, prasugrel, and ticagrelor reduce recurrent events in the first year after an ACS.
ß-blockers. These seem to be the most effective agents; they reduce the incidence, frequency, duration, and severity of silent ischemia according to the results of the Atenolol Silent Ischemia Study (ASIST) .Treatment with atenolol , 100 mg/d, reduced daily ischemia, as well as the risk of future adverse cardiac events at 1 year. The NICE guidelines recommends offering either a ß-blocker or calcium channel blocker as first-line treatment for stable angina, with the choice of drug depending on co-morbidities, contraindications and the person’s preference . ;(v) symptomatic treatment with nitrates, beta blockers, calcium channel blockers, and other anti-angina drugs; and (vi) revascularization by PCI or CABG in selected patients. Revascularization exerts favorable effects on symptoms, quality of life, exercise capacity, and survival, particularly in those with extensive CAD and documented moderate-to-severe ischemia. Additionally, future research is warranted to study the effect of newer medical therapies such as ranolazine and ivabradine or selected use of revascularization in those patients with persistent silent ischemia despite optimal current-era medical therapy.