Loosely translated, angina pectoris is a discomfort often described as a squeezing or pressure in the chest. Generally, discomfort appears with exertion and goes away with rest. Most likely, the cause of such discomfort is a fatty build-up and narrowing of one or more coronary arteries, which supply blood to the heart muscle.When coronary arteries are narrowed or blocked, there is a decrease in blood flow – and therefore, oxygen – to the heart muscle. This deprives the heart of nutrition and usually results in chest discomfort. The cause of the narrowing is atherosclerosis, or hardening of an artery, which is brought on by one or more risk factors, including cigarette smoking, hypertension (high blood pressure), high cholesterol, diabetes, family history (heredity), obesity, sedentary lifestyle and stress. It bears mentioning, however, that chest discomfort may not represent angina, but rather, pain in the muscles of the chest, gastrointestinal or lung problems.
At Lahey Clinic, the diagnosis of angina begins with a careful medical history taken by the patient's physician. Testing may include an electrocardiogram (ECG) and stress testing. Stress tests are generally performed on a treadmill, and the electrocardiogram is taken during the stress test. Sometimes the referring physician will also request that an imaging study be done with the stress test, either by echocardiography (i.e., ultrasound or sonogram) or with a nuclear radiopharmaceutical (i.e., thallium or myoview). In association with the ECG, the images provide the physician with the information necessary to consider a blockage as the problem.
If the patient's symptoms and the noninvasive tests suggest the need for further testing, the physician may suggest a coronary angiogram, or cardiac catheterization. During cardiac catheterization, a catheter (a thin, flexible plastic tube) is threaded under X-ray guidance through an artery in the leg or arm and up into the coronary arteries of the heart. Next, X-ray dye is injected through the coronary arteries and animated X-rays are taken to look for any blockages in the arteries. Recommendations for treatment can then be made.
Angina is generally treated according to one of three strategies. First and foremost is lifestyle modification combined with the use of medications. Quitting smoking, losing weight, getting exercise, and changing one's diet are the cornerstones of treatment, with which dieticians and cardiac rehab nurses can help.Medications often include the use of aspirin or aspirin-like drugs; cholesterol lowering medications such as statins (i.e., Zocor, Pravachol, Lipitor, Lescol, Crestor); Beta-blockers (i.e., atenolol, Toprol, metoprolol); long-acting nitrates (i.e., isosorbide) and calcium channel blockers (i.e., Norvasc, Plendil, Cardizem or Verapamil). Medication choice is at the discretion of the treating physician and is based on the patient's individual needs and lifestyle.Another treatment for angina is coronary angioplasty. Angioplasty takes about an hour, and can be performed under local anesthesia in the same sitting as the angiogram (catheterization), if needed. Once the catheter is in place in the artery, a small plastic tube with a balloon on the end is inserted and inflated briefly at the site of the blockage in the coronary artery. Balloon inflation opens the blockage, and often a stent (small metal tube) is placed there to help keep the artery open.If an angina patient has multiple blockages that are not amenable to angioplasty or if the left main coronary artery is severely blocked, coronary bypass grafting is generally recommended. During this surgery, the surgeon removes a vein from the patient's leg, an artery from within the patient's chest, and sometimes an artery from the forearm, and "bypasses" the blocked artery in the heart. Several different approaches may be taken; following a consultation with the referring cardiologist, the choice depends on the surgeon's opinion as to which approach is best for the individual patient. Coronary bypass grafting generally takes three to five hours, and requires an average hospital stay of five to six days. Patients are encouraged to adapt their lifestyles, including smoking cessation, change in diet, and often weight loss.