New guidelines for the treatment of atrial fibrillation – a heart condition that affects 250,000 Canadians – are promoting a radically different approach, saying the comfort of patients matters a lot more than the rhythm and rate of their heartbeat.
"We're placing a lot more emphasis on quality of life than on the numbers – because that's ultimately what matters," Laurent Macle, director of the electrophysiology fellowship program at the Montreal Heart Institute and co-author of the guidelines, said in an interview.
Patients with AF essentially suffer from an irregular and sometimes rapid heartbeat. It can happen in episodes lasting from minutes to weeks, or it may occur all the time for years.
Traditionally, they have spent long periods of time in hospital, and physicians have aimed to keep the heart rate of AF patients below 100 beats a minute using an array of medications. They were slow to use surgical procedures to correct the underlying heart rhythm problems.
But the new guidelines, published in Thursday's edition of the Canadian Journal of Cardiology, emphasize that AF patients should be treated more quickly and aggressively – beginning with shocking their heart right in the emergency room (which often restores normal rhythm).
"Shock and go is the best approach for most patients," Dr. Macle said. But he stressed that approach should only be taken if the symptoms have lasted less than 48 hours.
The guidelines, produced by a large group of cardiac experts under the auspices of the Canadian Cardiovascular Society, also call for more determined efforts to prevent the most dangerous side effect of AF, a stroke. Specifically, they recommend that patients at high risk of stroke be prescribed with the anti-coagulant dabigatran (brand name Pradax) instead of the much more common warfarin (Coumadin) because there are far fewer side effects. The catch though is that Pradax is not covered by provincial drug plans.
AF occurs when faulty electrical signals cause the atria – the two upper chambers of the heart – to contract fast and irregularly. Symptoms can include heart palpitations, fatigue and headaches, but some people have no obvious symptoms.
The biggest risk factor for AF is age: One in four Canadians over the age of 40 risks developing this anxiety-inducing, uncomfortable disease. After the age of 55, the incidence of AF doubles with each decade of life.
Rates of AF are higher in individuals with other heart conditions such as high blood pressure and valve problems, and those who undergo heart surgery. Thyroid problems, sleep apnea and excess alcohol consumption are also risk factors.
The most common treatment for AF is cardioconversion, shocking the heart to restore a normal rhythm. Anti-arrhythmia drugs are also used but they are often ineffective and can have numerous side effects.
For this reason, the guidelines recommend they only be used when necessary. For example, people who have intermittent symptoms should use "pill-in-pocket" therapy, meaning they only take the drugs when they have symptoms, not on a daily basis.
Drug therapy does not correct the underlying problem so the new guidelines also suggest that surgery be performed much more readily, specifically a procedure called catheter ablation. Most AF is caused by a build-up of tissue on the pulmonary veins, which disrupts electrical signals. Surgeons snake a thin tube (a catheter) through a small incision into the heart and cauterize (or burn off) that tissue.
"We used to have patients go through a lot of pills but now the recommendation is to go more quickly to catheter ablation," Dr. Macle said, because it has a success rate of 75 to 90 per cent.
The problem can also be corrected during open heart surgery, but the guidelines say that should only be done if the patient is already undergoing another procedure such as a bypass or valve replacement.
The new set of recommendations on the diagnosis and management of AF was last updated in 2005. Since then, major advances have been made in the management of the disease.
In addition to the paper version, the Canadian Cardiovascular Society is also creating, for the first time, an "app" for physicians so they can access then easily on their mobile devices.