|Rhythm and blues||Jun. 24, 2012|
|Written by: Marilyn Linton, QMI Agency|
|Atrial fibrillation can lead to strokes if untreated|
Tim Readman is no plumber, but he's good at explaining how the heart, as the body's main pump, affects the brain.
"If your central heating pump stops working, you don't get heat around the house," Readman says. "And if your heart isn't pumping properly, it affects the whole body system. The brain is especially vulnerable because it needs blood."
Readman, executive director of the Stroke Recovery Association of British Columbia, is on a campaign to educate Canadians about a condition known as atrial fibrillation or AF. The irregular heart rhythm, which is difficult to understand and not the easiest condition to treat, can nonetheless lead to strokes if left unattended.
There are currently 350,000 Canadians with AF, says Dr. Zaev Wulffhart, chief of cardiology at Southlake Regional Health Centre in Newmarket, Ont. "It's the most common rhythm disturbance around, and it is on the increase."
Everyone has the occasional skipped heartbeat, Wulffhart explains, but in AF there is a fast (often more than 100 beats a minute) irregular heart rhythm. When explaining AF to his patients, he thinks highways and tollgates.
"There's like a relay station, a kind of pacemaker, in the middle of the heart that directs the traffic from the top chamber to the bottom. If you think of the heart as a highway and that pacemaker as a kind of tollgate where the cars have to pay in order to go through, the cars will come to the gate, pay the attendant, and drive through," Wulffhart says.
"In AF, you have vehicles at varying speeds arriving at the tollgate where the toll master is trying his best to get all the cars through to the bottom. But he can't cope, and some traffic goes through quickly and other cars are delayed," Wulffhart says.
"At the top part of the heart (where the cars are waiting to go through), the blood can stagnate in that chamber by not flowing efficiently. While waiting, it can form little blood clots which then can cause strokes."
This rhythm problem, Wulffhart stresses, is not at all related to cardiac arrest; the word fibrillation makes people think it has to be treated with defibrillators to shock the heart back to beating. "It's a quality of life rhythm problem which carries with it a risk of stroke," the cardiologist says. "If your heart goes too fast or too slow in AF you can faint, but this is not a problem that would make someone drop dead."
Its causes can include high blood pressure, abnormal or defective heart valves, an overactive thyroid, lung disease or exposure to stimulants such as medications, caffeine, tobacco or alcohol. Sleep apnea, viral infections or previous heart surgery can also lead to AF. By the age of 80, approximately 15% of us will have AF. "The higher the prevalence of AF, the more likely your stroke will be related to it," says Wulffhart.
Hannah Sibeth is doing everything she can to avoid such a stroke. At age 61, a decade living with AF, and now a caregiver to husband, Paul, who suffered a stroke, the Aylmer, Que., special events planner says she used to go to ERs a lot. "Having an irregular heartbeat is most unnerving."
To improve her health, she has lost 50 pounds, learned to control her blood pressure, and was prescribed a blood thinner. Several treatments are offered AF patients, says Wulffhart: "You can slow the heartbeat through medication, correct it using an anti-arrhythmic drug, or use ablation."
Blood thinners are advised for anyone with AF but taking them requires strict monitoring because bruising and bleeding can be side effects of everything from aspirin to Coumadin to Pradaxa. In her business, Sijjbeth is careful about cutting herself while arranging flowers for an event. And while she appreciates the challenges of blood thinners, stroke is "no fun," she says. "It's debilitating and life changing for everyone."
Do you have AF?
A continuous erratic heartbeat is the most common symptom, but some people feel only the occasional butterflies in the chest, shortness of breath or lethargy. AF can be chronic and sustained or brief and intermittent. "If it comes and goes, and you are at your doctor's when your heartbeat returns to regular, the doctor may miss it." Further tests taken over a period of time by a device such as a Holter monitor can confirm AF. Adds Tim Readman: "Make sure you get yourself checked if you have a sensation that you are having abnormal heart rhythms or palpitations. Don't ignore it."
British Columbia's Hans Larsen has battled AF for over a decade and is devoted to researching the condition and offering information on up-to-date statistics, international studies and alternative medicine approaches. At afibbers.org you can also sign up for The Afib Report.
Risk versus benefit
Blood thinners always come with a bleeding and bruising risk, says Dr. Wulffhart who adds that many doctors now use the HAS-BLED score to calculate a patient's bleeding risks before prescribing anti-coagulants. Studies of some AF medications have shown that they increase heart attack risk, though some cardiologists dispute the claims. For more on AF, check out stopAfib.org, written by former AF patient Melanie True Hills.
The heart's four chambers include the two upper ones (atria) and the two lower (ventricles.) A group of cells called the sinus node acts like a natural pacemaker and produces the impulse that starts each heartbeat. In AF, the upper chambers experience chaotic electrical signals and the electrical connection between the atria and the ventricles is overloaded with impulses trying to get through to the ventricles. The result is a fast, irregular heart rhythm.
|MORE COLUMNS BY MARILYN LINTON, QMI AGENCY|