Angina pectoris is characterized by severe chest pain, pressure, or tightness. It affects, to some degree, ~6.5 million individuals in the United States.¹ The fundamental cause of angina pectoris is an imbalance between the oxygen requirement of the heart and the oxygen supplied to the heart by way of the coronary vessels.² Angina is also a symptom of ischemic heart.

Symptoms Associated with Angina

Although pain and discomfort are the classic symptoms related to angina attacks, patients should be alerted to other signs and symptoms that may be associated with angina. Episodes of pain or discomfort typically start under the breastbone but may radiate to other areas such as the arms, left shoulder, back, neck, jaw, or stomach. Patients also may experience other symptoms, such as^1,3 :

• Episodes of difficulty in breathing or shortness of breath
• Sweating, light-headedness, dizziness, extreme weakness, or anxiety
• Feeling of indigestion
• Nausea or vomiting
• Rapid or irregular heartbeats

Types of Angina

There are 3 types of angina: stable, unstable, and variant (also referred to as Prinzmetal's angina; Table 1⁴). Each year, there are ~400,000 new cases of stable angina.^3,5 An estimated 1 million patients are hospitalized each year with a primary diagnosis of unstable angina.⁶ Variant (Prinzmetal's) angina is rare and accounts for only 2 of every 100 cases of angina; it is caused by a coronary spasm.⁴

Diagnosing Angina

To determine whether an individual has angina, the primary health care provider can perform many types of tests. Examples of what the physician may do are as follows:

• Perform a physical examination that may include laboratory tests, an electrocardiogram, and stress tests
• Evaluate the types and severity of the symptoms
• Determine whether the individual has risk factors associated with the development of coronary artery disease (Table 2¹)

Treatment

In treating angina, various strategies may be used to effectively and safely manage the condition, depending on the severity of the symptoms. These treatment plans can include lifestyle modifications, the use of pharmacologic agents, cardiac procedures, and cardiac rehabilitation. The goals of treating angina are to successfully control the condition by reducing both the frequency and the severity of angina symptoms, as well as possibly preventing further complications.

The use of pharmacologic agents in conjunction with lifestyle modifications may improve an individual's quality of life. The cardiovascular agents commonly used to treat angina include nitrates, ß- blockers, and calcium channel blockers.

In February 2006, the FDA approved Ranexa (ranolazine), manufactured by CV Therapeutics, for the treatment of chronic angina. It is the first new drug approved to treat chronic angina in more than a decade. Because Ranexa prolongs the QT interval, it should be reserved for those individuals who have not responded to other antianginal medications.

Ranexa should be used in conjunction with amlodipine, ß-blockers, or nitrates. Ranexa is contraindicated in individuals with preexisting QT prolongation, in those with hepatic impairment, and in individuals taking drugs that prolong the QTc interval. The drug also is contraindicated in those individuals receiving potent and moderately potent CYP3A inhibitors, including diltiazem.⁷

Initially, Ranexa is dosed at 500 mg bid, and it may be increased to 1000 mg bid as needed, based on clinical symptoms. The maximum recommended daily dose is 1000 mg bid. Common adverse effects include dizziness, headache, constipation, and nausea.

In addition, angiotensin-converting enzyme inhibitors, antiplatelet drugs, and antihyperlipidemic agents, as well as anticoagulants, often are used in this patient population, depending on the patient's specific needs. Pharmacists are in a key position to monitor potential drug interactions as well as possible contraindications.

When a patient does not respond to medication, various invasive procedures such as angioplasty and coronary artery bypass surgery may be performed.

Ms. Terrie is a clinical pharmacy writer based in Haymarket,Va.

For a list of references, send a stamped, self-addressed envelope to: References Department, Attn. A. Rybovic, Pharmacy Times, Ascend Media Healthcare, 103 College Road East, Princeton, NJ 08540; or send an e-mail request to: arybovic@ascendmedia.com.