The straining of a bowel movement in the setting of underlying heart disease and high blood pressure certainly could cause a heart attack, stroke, or fainting episode. Elvis was said to have been prescribed pain medications, including codeine and hydrocodone, two drugs known to be very constipating. If he had some sort of underlying tendency toward chronic constipation, as Nichopoulos has speculated, any pain medication would have made things much worse.
When one strains to have a bowel movement, the effort transiently reduces the flow of blood back to the heart. There's a transient reduction in blood pressure and cardiac output, and a marked rise in heart rate. When the straining effort ceases, there's a big rush of blood to the heart followed by a gradual fall in the heart rate toward normal. This is called the "Valsalva maneuver." If there's underlying heart disease, such straining could result in a fatal heart arrhythmia or heart attack.
Question: Is nicotine bad for my health?
Answer: Nicotine is a naturally occurring compound in tobacco products and is the chemical that makes tobacco addictive. When nicotine is introduced to the body, it rapidly gets into the bloodstream. It can cross the "blood-brain" barrier and reach the brain within 10 to 20 seconds of inhalation.
Smokeless tobacco, which is held in the mouth for long periods, is particularly addictive because it releases much more nicotine than inhaled smoke.
Once the nicotine gets into the brain, it increases the flow of the brain chemical transmitter dopamine, creating a pleasurable response. Nicotine also increases alertness and suppresses appetite, which is part of its attraction. When blood levels begin to fall, people crave it and experience withdrawal symptoms.
Research from Brown University shows that nicotine itself can cause cardiovascular disease by promoting the invasion and damage of smooth muscle cells that line blood vessels. This process ultimately leads to the formation of artery-clogging plaques.
The best use of nicotine is to help folks break their tobacco addiction. The most successful method is a nicotine patch combined with some form of nicotine by mouth (gum, inhaler, lozenge). While tobacco use is far worse than nicotine replacement products, long-term nicotine use may not be as harmless as once thought.
Mitchell Hecht specializes in internal medicine. Send questions to "Ask Dr. H.," Box 767787, Atlanta, Ga. 30076. Due to the volume of mail, personal replies are not possible.