Your heart has four chambers: two upper chambers called atria, where blood enters the heart, and two lower chambers called ventricles, where blood leaves the heart. It also has a total of four valves -- two entryways between each atrium and ventricle, and two exit valves between the ventricles and the outside of the heart. These valves are small muscular rings that have small leaflets attached. When closed, these leaflets fit tightly together, preventing the flow of blood. When pressure builds behind the valves, they open, allowing blood to pass. The valves are one-way doorways, forcing blood in one direction so that it doesn't leak backward after passing through a valve.
The mitral valve, in the left side of your heart, is the exit gate leading out of your lower ventricle. (The mitral valve is also known as the bicuspid valve, because unlike the other valves, the mitral valve only has two leaflets, instead of three.) In this article, we'll look at a condition called mitral valve prolapse (MVP), which is when the mitral valve closes but the leaflets billow backward into the upper atrium. Mitral valve prolapse can cause mitral valve regurgitation, which is when your blood leaks through a poorly closed valve. In this case, some of the blood that's already passed from the atrium to the ventricle leaks back into the atrium. And that's not good.
There are five things you need to know about MVP, and the first one is on the very next page.
When MVP is symptomatic, the signs your body sends you are very similar to the warning signs of heart disease. You may feel tired or dizzy for no clear reason, have headaches, or experience sudden drops in blood pressure when you stand. Additionally, your own heartbeat may seem eerily noticeable, and your heart may feel like it's beating a mile a minute even if you're resting. Like with heart disease, you may feel pain or tightness in your chest.
It's safe to say that even if you think you're able to tell the difference between one heart disorder and another, you should seek medical attention if you notice any of these unusual symptoms and let the doctors sort it out. Doctors can't say for certain why MVP may give you a killer headache, and maybe it doesn't really matter. Your body is trying to tell you, "Hey pal, something's wrong!" Even the most bull-headed among us should be willing to listen to our own internal advice, right?
Men age 50 and up are most likely to have serious symptoms [source: NHLBI]. In our next section, you'll see that MVP's headaches, dizziness and crazy heart rhythms aren't actually all that common, even if MVP is.
Mitral valve prolapse affects around 2 percent of people in the United States [source: Mayo]. Some estimates place the frequency as high as 5 percent [source: Merck]. It occurs as often in men as it does in women.
Knowing that MVP is a common condition may make it easier for the rest of us to swallow the news that we may have it as well. Here's some more reassurance -- MVP may not cause you any trouble whatsoever. The majority of people with MVP lead perfectly healthy, happy lives [source: AHA]. It won't matter if your leaflets are the size of palm leaves, as long as the leaflets still properly function. The main worry is that if the leaflets bulge out, blood will regurgitate into the atrium. This isn't always the case, however. Sometimes prolapsed leaflets still form a tight seal and prevent blood from leaking through.
If there is leakage, it will probably produce a small murmur that your doctor can detect. If there's no sign of regurgitation and no other symptoms, then you may never know there was anything slightly different about your mitral valve in the first place.
If MVP is diagnosed without major symptoms, doctors will keep tabs on the condition throughout your lifetime to make sure your MVP isn't worsening. And here's more good news: A symptom-free condition won't take a single day off your life [source: Mayo].
Although most people will experience no problems from MVP, other people may be in serious risk. One of the symptoms of MVP is the development of arrhythmias, or abnormal heartbeats. Arrhythmias are often the result of regurgitation and usually affect the heart's upper chambers. Sometimes, the arrhythmia occurs in the form of atrial fibrillation, in which the heart quivers instead of pumps. This leaves the atria unable to pass blood along to the ventricles.
If you have MVP and feel an unusual heartbeat, it doesn't mean you're going to die. Most of the time, these arrhythmias aren't deadly. However, in cases of sudden heart failure, it has been found that the cause is often an arrhythmia, though it's not known for sure if the fatal arrhythmia is directly related to the faulty valve [source: Mayo]. If you have MVP but the leaflets are still forming an effective seal against leakage, it's unlikely that you'll experience arrhythmias. In some cases of MVP, older patients have been found to have higher chances of experiencing nonfatal arrhythmias [source: PACE].
MVP also increases the risk of stroke because blood pooling in the atrium may form clots [source: NHLBI]. These clots can then break up, pass through the bloodstream and block a blood vessel in the brain. This too, however, is quite rare and only occurs in the case of an extremely fast heartbeat.
What do your teeth have to do with MVP? Find out in the next section.
Mitral valve prolapse makes a person more susceptible to infections. Bacteria like to collect on faulty valves, and so it goes with MVP. By brushing and flossing, you can prevent your gums from getting inflamed or irritated. If the conditions in your mouth begin to mimic those of a college dormitory, bacteria from your mouth can wind up attaching to the thin, protective layer that lines the inside of the heart's chambers and valves, the endocardium. When the surface of the valve gets infected, it causes a condition known as infective endocarditis.
This serious condition degenerates the valve, ultimately leading to heart failure. If left untreated, endocarditis is fatal. Even when treated with antibiotics, it results in death between 10 and 30 percent of the time [source: McMahon]. If your Uncle Lenny's jack-o-lantern smile doesn't convince you to brush and floss regularly, the fear of infective endocarditis should do the trick. Once the atrial valve is infected, the bacteria often accumulate and then break off and travel to other parts of the body. About half the time, endocarditis will cause swelling and abscesses in the kidneys, and 20 percent of deaths are caused by breakaway bacteria that have created swelling in the brain [source: McMahon].
Anyone with a history of prior infection or with a transplanted prosthetic valve should take antibiotics before any medical or dental surgery due to the increased amount of bloodstream bacteria such procedures produce [source: AHA].
Next: Nobody's blaming you, we just want to help.
Unlike a three-pack-a-day smoker who has a bad ticker, people with MVP have nothing to feel guilty about. Most people with MVP were born with it, and floppy atrial leaflets sprout more often on some family trees than on others. Those not born with MVP got it as a side effect of other conditions, especially those that affect connective tissues like Marfan syndrome and Ehlers-Danlos syndrome. Even scoliosis can cause MVP.
Most people won't need treatment, but there's hope for those who experience problems. If symptoms are rhythm-related, your doctor may give you beta blockers, which lower blood pressure and relax blood vessels, allowing them to function normally. Other drugs can also get heartbeats back on track and prevent potentially deadly clotting. If the condition is serious, the leaflets can sometimes be surgically trimmed. When this isn't possible, the valve can be replaced with either a mechanical valve or a biological valve (coming from a deceased human or a pig). Biological valves are less likely to cause clotting but usually need replacing after a decade or so. Mechanical valves normally long outlive the rest of your body but require you to take blood thinners daily for the rest of your life to prevent platelets from getting too comfortable as they pass through the new digs.
So if you have MVP, take heart: It's not your fault, it may not cause problems, and most problems can be fixed.
For more articles on the heart and health, try the links on the next page.
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More Great Links
- American Heart Association. "2008 Focused Update Incorporated Into the ACC/AHA 2006 Guidelines for the Management of Patients With Valvular Heart Disease." Circulation. 2008;118: e523-e661. http://circ.ahajournals.org/cgi/content/full/118/15/e523
- American Heart Association. "Ask the Pediatric Cardiologist: Infective (Bacterial) Endocarditis." (Oct. 13, 2008). http://www.americanheart.org/presenter.jhtml?identifier=3051384
- American Heart Association. "Mitral Valve and Mitral Valve Prolapse." http://www.americanheart.org/presenter.jhtml?identifier=4717
- American Heart Association. "Your Heart and How it Works." (Oct. 13, 2008). http://www.americanheart.org/presenter.jhtml?identifier=1557
- Franklin Institute. "The Human Heart: An Online Exploration from the Franklin Institute." (Oct. 13, 2008). http://www.fi.edu/learn/heart/
- Mayo Foundation for Medical Education and Research. "Beta Blockers." July 1, 2008. (Oct. 26, 2008) http://www.mayoclinic.com/health/beta-blockers/HI00059
- Mayo Foundation for Medical Education and Research. "Heart Disease." (Oct. 13, 2008). http://www.mayoclinic.com/health/heart-disease/HB99999
- Mayo Foundation for Medical Education and Research. "Heather's Back: Full of energy and free of worry." 2008 (Oct. 13, 2008).http://www.mayoclinic.org/patientstories/story-45.html
- Mayo Foundation for Medical Education and Research. "Mitral Valve Prolapse." Jan. 24, 2008. (Oct. 26, 2008). http://www.mayoclinic.com/health/mitral-valve-prolapse/DS00504
- McMahon, R.F.T.; Sloan, P. Essentials of Pathology for Dentistry. Elsevier Health Sciences, 2000. ISBN 0443057060, 9780443057069. Pgs. 101-109. http://books.google.com/books?hl=en&id=EZ5RBdaatIIC&dq=Essentials+of+Pathology+for+Dentistry&printsec=frontcover&source=web&ots=x8vnMGkov8&sig=7q4mdACYD5JR0C8IqT_NZ0Sv1Vo&sa=X&oi=book_result&resnum=5&ct=result
- Medline Plus. "Heart Valve Diseases." U.S. National Library of Medicine and the National Institutes of Health. May 28, 2008 (Oct. 13, 2008). http://www.nlm.nih.gov/medlineplus/heartvalvediseases.html
- Merck. "Heart and Blood Vessel Disorders: Heart Valve Disorders." Reviewed by Paul H. Tanser, MD, May 2006 (Oct. 13, 2008). http://www.merck.com/mmhe/sec03/ch028/ch028a.html
- Merck. "Mitral Valve Prolapse (MVP)." May 2006. (Oct. 26, 2008) http://www.merck.com/mmhe/sec03/ch028/ch028c.html
- National Heart Lung and Blood Institute. "Mitral Valve Prolapse." (Oct. 26, 2008) http://www.nhlbi.nih.gov/health/dci/Diseases/mvp/mvp_signsandsymptoms.html
- PACE (Pacing and Clinical Electrophysiology). "Ventricular Arrhythmia Factors in Mitral Valve Prolapse."
- Babuty, D.; Cosnay, P.; Breuillac, J.C.; Charniot, J.C.; Delhomme, C.; Fauchier, L.; Fauchier, J.P. June 30, 2006. (Oct. 26, 2008).http://www3.interscience.wiley.com/journal/119969614/abstract?CRETRY=1&SRETRY=0
- Roizen, Michael F. M.D., and Mehmet C. Oz, M.D. "YOU: The Owner's Manual." HarperCollins. 2005.
- St. Jude Medical. "Heart Valve Replacement." 2008 (Oct. 13, 2008).http://www.sjm.com/procedures/procedure.aspx?name=Heart+Valve+Replacement
- Texas Heart Institute at St. Luke's Episcopal Hospital. "Valve Repair/Replacement." July 2007 (Oct. 13, 2008). http://www.texasheartinstitute.org/hic/topics/proced/vsurg.cfm
- The Society of Thoracic Surgeons. "Heart Surgery Terms." 2007 (Oct. 13, 2008). http://www.sts.org/sections/patientinformation/otherresources/heartsurgterms/index.html#acquiredaorticvalvedisease