Bradycardia means a significant slowing of the heart rate. It is usually not serious, but it can sometimes betray a cardiac anomaly or a cardiovascular disease in its own right. How to detect and deal with it? Insights from Dr Claude Kouakam, cardiologist, specialist in the management of heart rhythm disorders and head of the Syncope unit and the Non-Invasive Rhythmological Technical Platform at the Institut Coeur Lung of the CHU Lille.
Definition: what is bradycardia?
As stated above, bradycardia refers to a slower than average heart rate, is less than 60 beats per minute at rest. “The heart rate can go down to 50 beats per minute during the day at rest and up to 40 beats per minute at night,” says Dr Kouakam, who insists that it is theoretical valuesto be analyzed according to the patients’ feelings.
Relatively common in athletes, bradycardia can also be linked to aging, taking medication or even heart disease. According to their origin, we distinguish:
- THE physiological bradycardias ;
- THE iatrogenic bradycardia ;
- THE cardiac bradycardia ;
- and the secondary bradycardias.
Norms at rest: how fast does a heart normally beat?
A healthy heart usually beats between 60 and 90 times per minute. “But some great athletes can have a heart that beats 50 times per minute and carry themselves like charms!”, Underlines the cardiologist.
Bradycardia-tachycardia syndrome
Bradycardia-tachycardia syndrome, also known as “atrial disease”, is characterized by an alternation of phases during which the heart beats too slowly (bradycardia) and phases during which the heart beats too quickly (tachycardia).
Usually caused by a malfunction in the electrical activity of the sinus node, it can cause severe fatigue, dizziness, sickness, palpitations and chest pain.
Its support depends on its originbut usually includes taking medication to regulate heart rhythm, implanting a pacemaker, and/or having surgery to correct heart electrical abnormalities.
Fatigue, shortness of breath, dizziness… What signs should alert?
Bradycardia sometimes goes unnoticed because it is sometimes well tolerated by patients and does not cause symptoms. However, there are a few warning signs:
- a great fatigue ;
- and lack of enthusiasm ;
- and short of breathment ;
- a feeling of malaise or some dizziness ;
- the impression that his heart “stops” ;
- etc.
In the most serious cases, patients may even lose consciousness (syncope). And Dr. Kouakam added: “If the heart rate is 20 beats per minute, bradycardia can lead to cardiac arrest“.
Risks: is bradycardia dangerous? (Is a slow beating heart serious?)
Bradycardia is not necessarily dangerous, since it can remain asymptomatic.
However, in the event of disabling and recurrent symptoms, it must be taken care of for avoid any risk of complications linked, in particular, to syncope, which can cause serious falls and other deleterious consequences.
Not to mention that it is essential to eliminate underlying and potentially serious cardiovascular causes.
Causes: what can cause bradycardia?
We first distinguish between physiological causes, such as the practice of a sport at a high level or thee natural aging.
Iatrogenic bradycardias are linked to medication that can slow the heart rate, such as beta-blockers, certain heart failure medications, or certain blood pressure medications.
The so-called “secondary” bradycardias are, as their name suggests, consequent to certain chronic pathologiesas :
- hypothyroidism;
- epilepsy;
- jaundice;
- intracranial hypertension;
- certain infections, such as typhoid fever;
- sleep apnea syndrome;
- l’amylose ;
- and/or certain autoimmune diseases.
If all these causes have been ruled out, it is certainly a cardiac bradycardialinked to :
- myocardial infarction;
- an infection such as pericarditis, myocarditis or endocarditis;
- an abnormality of the sinus node (for example, scars left by another heart disease);
- one or more abnormalities in the cardiac electrical impulse between the atria and the ventricles (atrioventricular block);
- or hemochromatosis (a genetic disease characterized by intestinal hyperabsorption of iron).
Who are the people at risk?
Bradycardia can affect anyone, but some audiences are more “at risk”, such as:
- old people ;
- athletes (eg freedivers);
- patients treated with certain drugs;
- people with heart disease;
- and people in a state of total relaxation after a relaxation or meditation session.
How do we diagnose it? What exams to take?
The diagnosis of bradycardia requires a thorough clinical examination: “we take into account the pulse, cardiac auscultation, age, history, current treatments and lifestyle of each patient”, insists Dr. Kouakam.
To invalidate or confirm his diagnosis, he can prescribe one of these tests:
- a stress test;
- cardiac ultrasound;
- a Holter recording;
- an implantable heart monitor;
- etc.
Treatment: what management to limit the impact of bradycardia?
The management of bradycardia obviously depends on its cause (so-called symptomatic management).
“The choice of treatment depends not only on the cause of the bradycardia, but also on its impact on the daily lives of patients“, insists the cardiologist.
When the bradycardia seems benign and does not impact daily life, it is possible to do without treatment (without forgetting monitoring). But in more severe cases, the installation of a pacemaker or implantable pacemaker is essential to manage the heart rate and accelerate it if necessary.
Diet, sport, sleep: how to deal with bradycardia?
Most patients suffering from bradycardia are not affected on a daily basis and lead a completely “normal” life. Similarly, wearing a pacemaker does not complicate everyday life beyond measure.
In both cases, several lifestyle rules are necessary as a precaution:
- limit alcohol and caffeine consumption;
- limit — or even stop — smoking;
- avoid recurring sources of stress ;
- adopt a balanced diet;
- do not try to increase your heart rate at all costs
- and regularly engage in appropriate physical activity.
Also remember to regularly consult your doctor or cardiologist to take stock. And if new symptoms appear, notify them quickly.