Atrial fibrillation: a topic of interest at the Montreal Heart Institute

Atrial fibrillation is the most common heart rhythm disorder, affecting about 700,000 Canadians. Find out more about this cardiovascular condition that is a topic of interest for many researchers at the Montreal Heart Institute.

Atrial fibrillation

Atrial fibrillation is characterised by quick and irregular heart beats that prevent the heart from efficiently pumping blood to other organs in the body.

This cardiovascular disease affects the heart’s upper cavities also known as the atria. When a heart is in atrial fibrillation, the number of electrical impulses in the atria can be as high as 400 impulses per minute. This causes the ventricles to contract in an irregular, quick way.

This arrythmia is the result of an abnormal firing of electrical impulses, which makes the heart’s job more difficult.

Factors of risk

Several factors can increase the risks of atrial fibrillation:

• Heart disease (involving the valves or muscle)
• Age
• Diabetes
• High blood pressure
• Hyperthyroidism
• Coronary disease or an anomaly of the cardiac muscle or valves
• Sleep apnea
• Obesity
• Heavy drinking
• Family history of atrial fibrillation

Symptoms

The symptoms associated with atrial fibrillation can vary. In fact, about 30% of cases are asymptomatic. However, this condition can also be associated with severe symptoms at its onset.

Atrial fibrillation can lead to chest pains and, most often, palpitations which are felt as a quivery and/or irregular heartbeat.

Other symptoms of atrial fibrillation include shortness of breath, dizziness, fatigue, anxiety, or an inability to carry out daily tasks.

Diagnosis and treatment

If an individual experiences frequent, long-lasting palpitations or other symptoms, a physician may prescribe non-invasive exams to investigate the presence of atrial fibrillation. This condition may also unexpectedly be diagnosed during a routine physical exam.

Treatments for atrial fibrillation are first and foremost focused on controlling the frequency or rate of the irregular heartbeat. This is also supported by a treatment to prevent the formation of blood clots.

Because atrial fibrillation is a chronic disease, its treatment involves a multifaceted approach that must be constantly optimized. The Montreal Heart Institute’s atrial fibrillation clinic provides specialized medical expertise to patients who have trouble managing their condition.

Atrial fibrillation and strokes

One possible complication of atrial fibrillation is a stroke. In fact, 1 out of 6 strokes is caused by this condition. The atria’s haphazard contractions reduce blood flow which can then accumulate in the upper chambers of the heart. Blood clots can then form and get lodged in the brain when the blood is pumped towards the rest of the body, leading to a stroke.

Unfortunately, the risks of stroke increase with age and when combined with other risk factors such as high blood pressure, diabetes, a history of strokes, heart valve disease, and heart failure. Anticoagulant drugs are recommended for patients meeting these criteria and are efficient at preventing strokes. Thankfully, most patients treated for atrial fibrillation enjoy a high quality of life.

The BRAIN-AF study

According to some researchers at the Montreal Heart Institute, strokes caused by atrial fibrillation could be responsible for cognitive impairment and an increased risk of dementia, specifically in young patients with atrial fibrillation who do not take anticoagulants.

The BRAIN-AF study, led by Dr. Lena Rivard and her colleagues Dr. Denis Roy and Dr. Paul Khairy, seeks to understand the effects of cardiovascular diseases on cognitive decline and the ways of preventing this from occurring. This is the world’s first study that aims to demonstrate a link between atrial fibrillation and cognitive impairment in young patients. The results of the BRAIN-AF study could benefit the nearly 175,000 Canadians aged 65 or under who are affected by this heart rhythm disorder.

The study’s team wants to prove the efficiency of an anticoagulant called rivaroxaban to treat atrial fibrillation and thereby develop a new preventive approach for cognitive impairment and dementia.

Help support the Montreal Heart Institute’s fight against atrial fibrillation and other cardiovascular diseases.