Monday, June 25, 2012
DocTalk: I’ll take euphemisms for $1,000 Alex.
Alex: The answer is…no such thing.
DocTalk: What is a mild heart attack?
The news was filled with stories that Alex Trebek, long time host of Jeopardy, had been hospitalized because of a minor heart attack. There is no doubt that there are heart attacks can be more or les s severe, depending upon how much heart muscle has been damaged, but the idea that a minor or mild heart attack exists, seems a little optimistic. It’s like telling somebody that they are just a little bit pregnant. Having a heart attack is a big deal and there is always the risk of sudden death because the irritated heart muscle can decide to stop beating.
It’s all about semantics. The heart is a muscle like any other in the body. It has blood vessels that supply it with oxygen rich blood to allow each muscle cell to function. If the blood vessels to the heart narrow and there isn’t enough blood to supply the needs of the heart, it starts to ache or hurt and this is called angina. If you run fast, your legs may start to hurt because the leg muscles may outstrip the ability of the body to provide oxygen. Same story if you lift a lot and your arms get tired. But while you can stop to rest your arms and legs, it’s hard to ask your heart to take a break and stop beating.
In classic angina, the chest pain, ache, tightness, indigestion, shortness of breath or whatever might be the equivalent, is brought on by activity and gets better with rest. Over time, as the blood vessels narrow, less activity brings on more pain and that pain takes longer to resolve. If a blood vessel closes off completely, the part of the heart muscle it supplies dies and that is called a heart attack. If it is one of the major blood vessels to the heart, lots of muscle can be damaged. If it is a tiny blood vessel, then perhaps less muscle dies. This perhaps can classify a heart attack as major or minor, but it fails to take into account an important point: anytime heart muscle becomes irritated, it can cause the heart rhythm to change and cause sudden death.
There is a basic diagnosis progression in the ER when somebody presents with chest pain that is likely coming from their heart.
• An EKG is done immediately looking for classic signs of a heart attack or myocardial infarction. If this is positive, it means that a major blood vessel has been clogged and there is true urgency to get it open either by going to the cath lab and having a cardiologist put in a stent to open the blood vessel, or if that isn’t available, option two is injecting a clot busting drug into an IV and hopefully opening the blocked blood vessel.
• If the EKG is normal, then blood tests are done to look for chemicals that damaged heart muscles can leak into the blood stream. It can take 6 or 12 hours for the chemicals called troponin and myoglobin to be detected.
• If the blood tests are positive, it means that a heart attack has occurred and it is important to proceed to heart catheterization to see whether there are narrowed blood vessels that can be opened with a stent or whether open heart surgery may be needed to bypass blocked blood vessels.
• If the blood tests are negative, then there is no heart damage but the risk of heart disease and future heart attack still exists and the heart needs to be imaged in some way, whether that is a stress test, an echocardiogram or ultrasound or by heart catheterization.
Throughout this process, the patient is kept on heart monitors to make certain life threatening heart rhythms do not occur. Should the electrical signals in the ventricle, the lower chamber of the heart that does the pumping, change from a regular impulse into chaotic ventricular fibrillation, the heart stops beating and sudden death occurs. The electrical short circuit doesn’t care if a little or lot a heart muscle is damaged is irritable.
So Alex, to explain my answer: You may have a mild heart attack that did not damage the pumping ability of your heart muscle, BUT your minor heart attack can cause ventricular fibrillation and that makes it a big deal. Just like being pregnant, you can’t have a little sudden death and that means you can’t have a minor heart attack.