After assessing and manipulating alterable risk factors, a regular exercise program should be undertaken with caution in a graduated fashion and with adequate supervision to improve cardiovascular and muscular fitness.
Nitrate therapy should be the first step in managing acute attacks of chronic stable angina if the episodes are infrequent. If angina occurs no more often than once every few days, then sublingual nitroglycerin 0.3 to 0.4 mg sublingually may be used about 5 minutes prior to the time of the activity. Nitroglycerin spray may be useful when inadequate saliva is produced to rapidly dissolve sublingual nitroglycerin or if a patient has difficulty opening the tablet container. The response usually lasts about 30 minutes.
When angina occurs more frequently than once a day, chronic prophylactic therapy should be instituted. BETA-adrenergic blocking agents may be preferable because of less frequent dosing and other desirable properties (eg. potential cardioprotective effects, antiarrhythmic effects, lack of tolerance, antihypertensive efficacy). The appropriate dose should be determined by the goals outlined for heart rate and DP. An agent should be selected that is well tolerated by individual patients at a reasonable cost. Patients most likely to respond well to beta blockade are those with a high resting heart rate and those with a relatively fixed anginal threshold (i.e., their symptoms appear at the same level of exercise or workload on a consistent basis).
Calcium channel antagonists have the potential advantage of improving coronary blood flow through coronary artery vasodilation as well as decreasing MVO2 and may be used instead of beta-blockers for chronic prophylactic therapy. They are as effective as beta blockers and are most useful in patients who have a variable threshold for exertional angina. Calcium antagonists may provide better skeletal muscle oxygenation, resulting in decreased fatigue and better exercise tolerance. They can be used safely in many patients with contraindications to beta-blocker therapy. The available drugs have similar efficacy in the management of chronic stable angina. Patients with conduction abnormalities and moderate to severe LV dysfunction (EF less than 35%) should not be treated with Verapamil, whereas amlodipine may be used safely in many of these patients. Diltiazem has significant effects on the AV node and can produce heart block in patients with preexisting conduction disease or when other drugs with effects on conduction (eg. digoxin, beta blockers) are used concurrently. Nifedipine may cause excessive heart rate elevation, especially if the patient is not receiving a beta blocker, and this may offset its beneficial effect on MVO2. The combination of calcium channel blockers and beta-blockers is rational because the hemodynamic effect of calcium antagonists is complementary to beta blockade. However, combination therapy may not always be more effective than single-agent therapy.
Chronic prophylactic therapy with long-acting forms of nitroglycerin (oral or transdermal), ISDN, ISMN, and pentaerythritol trinitrate may also be effective when angina occurs more than once a day. Monotherapy with nitrates should not be first-line therapy unless beta-blockers and calcium channel blockers are contraindicated or not tolerated. A nitrate-free interval of 8h/day or longer should be provided to maintain efficacy. Dose titration should be based on changes in the DP. The choice among nitrate products should be based on changes in the DP. The choice among nitrate products should be based on experience, cost, and patient acceptance.
Nitrate therapy should be the first step in managing acute attacks of chronic stable angina if the episodes are infrequent. If angina occurs no more often than once every few days, then sublingual nitroglycerin 0.3 to 0.4 mg sublingually may be used about 5 minutes prior to the time of the activity. Nitroglycerin spray may be useful when inadequate saliva is produced to rapidly dissolve sublingual nitroglycerin or if a patient has difficulty opening the tablet container. The response usually lasts about 30 minutes.
When angina occurs more frequently than once a day, chronic prophylactic therapy should be instituted. BETA-adrenergic blocking agents may be preferable because of less frequent dosing and other desirable properties (eg. potential cardioprotective effects, antiarrhythmic effects, lack of tolerance, antihypertensive efficacy). The appropriate dose should be determined by the goals outlined for heart rate and DP. An agent should be selected that is well tolerated by individual patients at a reasonable cost. Patients most likely to respond well to beta blockade are those with a high resting heart rate and those with a relatively fixed anginal threshold (i.e., their symptoms appear at the same level of exercise or workload on a consistent basis).
Calcium channel antagonists have the potential advantage of improving coronary blood flow through coronary artery vasodilation as well as decreasing MVO2 and may be used instead of beta-blockers for chronic prophylactic therapy. They are as effective as beta blockers and are most useful in patients who have a variable threshold for exertional angina. Calcium antagonists may provide better skeletal muscle oxygenation, resulting in decreased fatigue and better exercise tolerance. They can be used safely in many patients with contraindications to beta-blocker therapy. The available drugs have similar efficacy in the management of chronic stable angina. Patients with conduction abnormalities and moderate to severe LV dysfunction (EF less than 35%) should not be treated with Verapamil, whereas amlodipine may be used safely in many of these patients. Diltiazem has significant effects on the AV node and can produce heart block in patients with preexisting conduction disease or when other drugs with effects on conduction (eg. digoxin, beta blockers) are used concurrently. Nifedipine may cause excessive heart rate elevation, especially if the patient is not receiving a beta blocker, and this may offset its beneficial effect on MVO2. The combination of calcium channel blockers and beta-blockers is rational because the hemodynamic effect of calcium antagonists is complementary to beta blockade. However, combination therapy may not always be more effective than single-agent therapy.
Chronic prophylactic therapy with long-acting forms of nitroglycerin (oral or transdermal), ISDN, ISMN, and pentaerythritol trinitrate may also be effective when angina occurs more than once a day. Monotherapy with nitrates should not be first-line therapy unless beta-blockers and calcium channel blockers are contraindicated or not tolerated. A nitrate-free interval of 8h/day or longer should be provided to maintain efficacy. Dose titration should be based on changes in the DP. The choice among nitrate products should be based on changes in the DP. The choice among nitrate products should be based on experience, cost, and patient acceptance.
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