Treatment of Stable Angina: An Update

Heart attacks are common causes of death, especially in the urban, high-stressed world. They are sometimes preceded by repeated attacks of chest pain, referred to as angina. The pain may radiate to the left shoulder, arm or jaw. A recent article reviewed the current guidelines for treating stable angina pectoris that are developed by the American College of Cardiology Foundation (ACCF) and the American Heart Association (AHA). A summary of the article is provided below: Stable angina pectoris refers to cardiac chest pain that occurs with exertion or emotional stress. If the chest pain persists for two or more months and does not vary in severity, character or with respect to triggering factors, the condition is called chronic stable angina pectoris. Current guidelines emphasize not only on treating the angina with medications, but also bringing about lifestyle modifications, and controlling blood pressure, cholesterol levels and diabetes, if present.

Among the lifestyle modifications that could reduce angina symptoms, avoidance of smoking and alcohol is advised. Regular brisk walking for 30 to 60 minutes or other similar exercise is known to keep the heart healthy, of course depending on the underlying capacity of the patient. Weight should be controlled with a balanced diet and adequate activity. The salt and cholesterol content of the diet should be limited.

High blood pressure adds to the work of the heart. Medications like beta blockers or ACE inhibitors are used to control the blood pressure; these medications also help to improve angina symptoms. High cholesterol levels should be controlled through diet and medications to prevent further worsening of the angina. Diabetes should be treated with regulation of diet and anti-diabetes medications. Rosiglitazone, an antidiabetes drug, should not be used in diabetes patients with stable angina.

Nitrates are the standard drugs used to treat an attack of angina. They dilate blood vessels and reduce the work of the heart. A tablet of nitroglycerin is placed under the tongue following an angina attack; if the patient does not experience any relief, the tablet is repeated every 5 minutes for a total of 3 tablets. Nitrates that act over longer durations are also available.

Other drugs are used mainly to prevent angina attacks. These include aspirin, which is administered in a low dose of 75 to 162 mg; this dose is much less than the dose used to treat headaches and other aches. In patients who cannot be given aspirin due to a possibility of a side effect, another drug, clopidogrel may be used as an alternative.

Drugs belonging to the group ACE inhibitors like ramipril and lisinopril reduce the work load of the heart, and therefore improve its functioning. Newer drugs like losartan and valsartan may be used in those cases that experience side effects with ACE inhibitors.

Drugs belonging to the beta-blocker group include carvedilol, metoprolol, or bisoprolol. These slow down the heart rate and therefore reduce the work and oxygen requirement of the heart. They should be started in all patients with angina, unless there is a definite contraindication. Calcium channel blockers like diltiazem and verapamil also bring about an action similar to beta blockers. They can be used in those cases where beta blockers cannot be prescribed.

Ranolazine is the newest drug approved for the treatment of chronic angina. It is used in cases where a beta blocker cannot be used or is insufficient to prevent angina. Currently, it is used only as a second-line drug in angina.

Thus, a combination of medications and lifestyle changes are recommended for the treatment of stable angina.

Reference:

The Pathophysiology and Treatment of Stable Angina Pectoris; Suzanne Albrecht et al; US Pharm. 2013;38(2):43-60. 

Source-Medindia