Posted by steve giddings on June 11, 2002 at 23:06:08:
In Reply to: Re: Three weeks post-op and high heart rhythm posted by Henry Alken on June 11, 2002 at 15:32:22:
Every drug has its own set of actions and its own set of side effects. The trick is to pick the drug that does the most good and the least potential harm for each clinical setting. Each patient is different. Rhythmol, propofenone, is a relatively selective ion channel poison. It blocks the one of the types of holes that sodium uses to travel through cell membranes. By doing so, it alters the electrical characteristics of the heart. It decreases the chance of a spontaneous depolarization, and also changes the rate at wehich heart cells recover after they depolarize. This decreases the chance for AF in many patients. The bad rap against this class of drugs, which also includes flecainide and encainide, is that they may increase the chance for lethal arrhytmias and sudden death in patients with hearts damaged by previous heart attack. They do not seem to do this in otherwise healthy hearts,(as in lone a fib). SO they may be a good choice in some patients.
Amiodarone also suppresses a fib, and does not cause the smae increase in risk for sudden death in patients with damaged hearts. For this reason it is used more in this type of patient. It is being replaced to some degree by implanted defibrillators (AICDs). It has more potential side effects, including pulmonoary fibrosis, both hypo and hyperthyroidism in different clinical settings, liver failure, lenticualr deposits, photosensitivity rashes, can turn the skin blue/gray, etc. These effects are for the most part dose dependent. They were also seen in patients who were desperately ill (in whom the drug was otherwise lifesaving).
Amio is probably somewhat more effective in controlling af than other drugs, and the incidence of side effects is quite low in patients who are on the low doses typically used to treat AF.
Which drug to use (if any) is a judgment call that requires a fair amount o information and background knowledge.
P waves are the electrical trace that the atria creates on ekg when they contract normally. You don't see normal p waves with flutter. After the maze, the atria may be so damaged/weak that there is no perceptible P wave on a regular ekg. Often you can pick uop small p waves using specially placed leads (like in the esophagus). They tend to get bigger as the atria recover.
- Re: Three weeks post-op and high heart rhythm Woodland Anne 18:30:25 6/13/2002 (0)