LiveWorld Transcripts

Houston Chronicle presents

Dr. Coulter
"Ask the Doctor": Heart Failure

February 15, 2000

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Sarah01: How does exercise affect my blood pressure? What's the correct blood pressure level?

Dr Coulter: People who exercise chronically tend to have lower blood pressures. However, when you exercise, sometimes your blood pressure goes up. But that is normal. A normal blood pressure, when you're not exercising, should be between 100 and 140 for systolic, and diastolic pressure between 50 and 90.

Sun-moon-stars: What percentage of persons who have had a cardiac event will experience heart failure at a later date?

Dr Coulter: That's a good question! The risk of developing heart failure after a cardiac event is directly proportional to the systolic function of the heart following the event. If the coronary event is the first one the patient has ever had, and the patient does not have a heart attack, then the risk is low. However, if they've had multiple heart attacks, they've likely damaged their heart over time and are at greater risk for developing heart failure. So the more damaged your heart is, the more likely you are to experience heart failure.

Dragonlvr: How important is diet in preventing future heart failure occurrences?

Dr Coulter: Diet is EXTREMELY important to patients who have a history of heart failure. The reason is that a reduced heart function precludes the heart from emptying completely. This makes the patient extremely sensitive to volume changes. Therefore, any increase in salt intake will lead to increase in intravascular volume, which can overwhelm the capacity of the heart to pump, and lead to elevated heart pressures and subsequent symptoms of congestive heart failure. (That's why it's called congestive.)

Saladgrazer: I have heard a lot about these all-protein diets. They seem to promote high fat foods and sound like they would be terrible for your heart! Are they really all that they are cracked up to be?

Dr Coulter: First of all, these high fat diets may be VERY unwise in a female who is overweight, in her 40s, and at risk for gall bladder disease, AKA gallstones. They have been known to provoke gall bladder attacks, which lead to a gall bladder operation. These dietary crazes are new, and have not been well studied from a cardiac perspective. However, it is well known that for every decrease in your cholesterol level, there is an associated increase in your life expectancy of two - three percent.

Sarah01: Can you explain how aspirin works fast enough to help save a life during a heart attack?

Dr Coulter: My favorite question! I love aspirin! Aspirin is a very common compound, which was initially purified from the bark of the willow tree. Among its therapeutic properties, aspirin immediately and irreversibly inhibits platelet aggregation. Heart attacks are caused by a ruptured atherosclerotic plaque (like a pimple), which occurs in a coronary artery, a heart artery. When the rupture occurs, oooey-goooey cholesterol junk oozes into the blood stream, where platelets are floating by. This causes immediate platelet plugging, which obstructs flow and causes a heart attack. Aspirin works by preventing the platelet plug from growing, and helps to re-establish flow in an initially occluded artery. One aspirin, chewed during a heart attack, will reduce the risk of dying by 23 percent. Just one pill! Taken even at home. Taken as early as possible. However, the benefits of aspirin, taken daily, prevent the chance of having a heart attack by another 25 percent. Extensive data indicates that patients greater than 55 years who are at risk of a heart attack, should take a baby aspirin every day. This prevents strokes as well as heart attacks.

Sigmagirl: My husband was born with ventricular septal defect, and had it surgically repaired when he was 16. Can you give me more information on this birth defect? Do I need to worry about my children being born with it? (He has no family history of other heart problems.) Thanks!

Dr Coulter: Good question! A ventricular septal defect is a hole between the ventricles, which allows the improper mixing of oxygenated and deoxygenated blood. This can lead, if not repaired and if large, to increases in lung pressures which damage the blood vessels in the lung and put further pressure on the right side of the heart. That is the reason that the decision was made to surgically correct this hole at the age of 16. Many children are born with small VSDs that close on their own. Thus, many children born with VSDs do not need surgical repair. However, if they are going to close naturally, they generally do so before the age of 8. Isolated VSD abnormalities do not tend to be genetic, however, patients with multiple cardiac abnormalities may have a genetic syndrome, which may be passed down to subsequent generations. But it does not sound like this applies to your husband, or your children.

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