home *** CD-ROM | disk | FTP | other *** search
- Date sent: Sat, 27 Apr 1996 22:00:19 -0400
-
-
-
- QUESTION: What is Angina? And
- what is the cure?
- ================================
- RESPONSE:
- Angina refers to the pain arising from lack of adequate blood supply to the
- heart muscle. Typically, it is a crushing pain behind the breastbone in the
- center of the chest, brought on by exertion and relieved by rest. It may at
- times radiate to or arise in the left arm, neck, jaw, left chest, or
- back. It is frequently accompanied by sweating, palpitations of the
- heart, and generally lasts a matter of minutes. Similar pain syndromes
- may be caused by other diseases, including esophagitis, gall bladder
- disease, ulcers, and others.
- Diagnosis of angina begins with the recognition of the consistent
- symptoms. Often an exercise test with radioactive thallium is performed
- if the diagnosis is in question, and sometimes even a cardiac
- catheterization is done if the outcome is felt necessary to make
- management decisions. This is a complex area which requires careful
- judgment by physician and patient.
- Angina is a manifestation of coronary artery disease, the same
- disease leading to heart attacks. Coronary artery diseas refers to
- those syndromes caused by blockage to the flow of blood in those
- arteries supplying the heart muscle itself, i.e., the coronary arteries.
- Like any other organ, the heart requires a steady flow of oxygen and
- nutrients to provide energy for rmovement, and to maintain the delicate
- balance of chemicals which allow for the careful electrical rhythm
- control of the heart beat. Unlike some other organs, the heart can
- survive only a matter of minutes without these nutrients, and the rest
- of the body can survive only minutes without the heart--thus the
- critical nature of these syndromes.
- Causes of blockage range from congenital tissue strands within or
- over the arteries to spasms of the muscular coat of the arteries
- themselves. By far the most common cause, however, is the deposition of
- plaques of cholesterol, platelets and other substances within the
- arterial walls. Sometimes the buildup is very gradual, but in other
- cases the buildup is suddenly increased as a chunk of matter breaks off
- and suddenly blocks the already narrowed opening.
- Certain factors seem to favor the buildup of these plaques. A strong
- family history of heart attacks is a definite risk factor, reflecting
- some metabolic derangement in either cholesterol handling or some other
- factor. Being male, for reasons probably related to the protective
- effects of some female hormones, is also a relative risk. Cigarette
- smoking and high blood pressure are definite risks, both reversible in
- most cases. Risk also increases with age. Elevated blood cholesterol
- levels (both total and low density types) are risks, whereas the high
- density cholesterol level is a risk only if it is reduced. Possible,
- but less well-defined factors include certain intense and hostile or
- time-pressured personality types (so-called type A), inactive lifestyle,
- and high cholesterol diets.
- Medications are increasingly effective for symptom control, as well
- as prevention of complications. The oldest and most common agents are
- the nitrates, derivatives of nitroglycerine. They include
- nitroglycerine, isosorbide, and similar agents. Newer forms include
- long acting oral agents, plus skin patches which release a small amount
- through the skin into the bloodstream over a full day. They act by
- reducing the burden of blood returning to the heart from the veins and
- also by dilating the coronary arteries themselves. Nitrates are highly
- effective for relief and prevention of angina, and sometimes for
- limiting the size of a heart attack. Used both for treatment of
- symptoms as well as prevention of anticipated symptoms, nitrates are
- considered by many to be the mainstay of medical therapy for angina.
- The second group of drugs are called "beta blockers" for their
- ability to block the activity of the beta receptors of the nervous
- system. These receptors cause actions such as blood pressure elevation,
- rapid heart rate, and forceful heart contractions. When these actions
- are reduced, the heart needs less blood, and thus angina may be reduced.
- The newest group of drugs for angina is called the calcium channel
- blockers. Calcium channels refer to the areas of the membranes of heart
- and other cells where calcium flows in and out, reacting with other
- chemicals to modulate the force and rate of contractions. In the heart,
- they can reduce the force and rate of contractions and electrical
- excitability, thereby having a calming effect on the heart. Although
- their final place in heart disease remains to be seen, they promise to
- play an increasingly important role.
- When medications are unsuccessful, or if there is concern about an
- impending or potential heart attack, coronary bypass surgery is highly
- successful in reducing symptoms. Whether or not it prolongs survival is
- questionable for most patients.
- Angina which is new or somehow different from previous episodes in
- any way is termed unstable angina, is a medical emergency, and
- requires urgent attention. Research is active, and careful medical
- follow-up is important.mergency, and
- requires urgent attention. Research is active, and careful medical
- follow-up is important.
-