Bradycardia is the medical name for when an individual’s heart rate is slower than normal. The average healthy heart rate for an adult should be between 60 to 100 beats per minute. However, if you are diagnosed with bradycardia, your resting heart rate will be less than 60 times per minute.
The low heart rate caused by bradycardia can cause significant problems if the heart isn’t pumping enough oxygen-rich blood around the body. For some people, bradycardia doesn’t induce any complications or symptoms.
Bradycardia can cause a detrimental effect on your brain and other vital organs within the body. You may suffer from not receiving enough oxygen, causing symptoms such as:
- The feeling of nearly fainting or fainting (syncope)
- Shortness of breath
- Feeling fatigued
- Chest pains and not being able to breathe properly
- Feeling confused and memory problems
- Becoming tired easily from physical activities
If you’re suffering from any of the above symptoms, you may have bradycardia and it’s important for you to book an appointment with your physician for an examination.
A number of reasons can cause bradycardia within a patient’s heart. The common reasons that bradycardia can be caused by are:
- Damaged heart tissue from a heart attack or heart disease
- Damaged heart tissue as a result of aging
- A congenital heart defect
- Myocarditis – an infection of the heart’s tissue
- A complication during or after heart surgery
- Hypothyroidism – an underactive thyroid
- A chemical imbalance in the blood such as a potassium or calcium deficiency
- Obstructive sleep apnea
- Rheumatic fever or lupus
- Certain medications for treating arrhythmias and high blood pressure
The heart consists of four chambers, the two upper chambers called the atria and the two lower chambers called ventricles. The sinus node, which acts as a natural pacemaker controls your heartbeats by producing electrical impulses.
The electrical impulses travel across the atria, resulting in them to contract and pump blood into the ventricles. The impulses then proceed to arrive at a cluster of cells referred to as the AV node, which then sends the impulses to a group of cells called the bundle of His. The bundle of His transmits signals down the branches that serve the left and right ventricles which makes them contract and pump blood.
The right ventricle sends blood lacking in oxygen to the lungs to be refreshed and the left ventricle sends refueled, oxygenated blood to the rest of the body. Bradycardia can also occur when electrical signals within the heart slow down or are blocked, causing the body to receive blood that isn’t properly oxygenated.
Sinus Node Issues
Bradycardia can often start in the sinus node, resulting in electrical impulses that are slower than they should be. Furthermore, a slower heart rate might occur because the sinus node is failing to discharge at a regular rate. The sinus node may also discharge an impulse that becomes blocked before the atria contracts.
Heart Block Issues
Heart block or atrioventricular block is caused when electrical signals that are transmitted from the atria aren’t correctly transmitted to the ventricles. There are three distinct classifications for heart block, depending on the severity of the blockage.
The types of heart block:
- First degree: heart block in its mildest form, all of the electrical signals from the atria eventually reach the vehicles, however, the signals are slowed down.
- Second degree: Not all of the electrical signals are able to reach the ventricles, causing some of the heartbeats to stop and it results in a slower rhythm that may also be irregular.
- Third degree: This is the most severe, none of the impulses from the atria are able to reach the ventricles.
There are many risk factors involved for patients that may get diagnosed with bradycardia such as age and lifestyle. There’s an increased risk of developing bradycardia if you have high blood pressure, smoke excessively, drink alcohol heavily, recreationally use drugs or suffer from extreme stress and anxiety.
If you feel like you’re developing any of the symptoms of bradycardia, you can check your heartbeat by performing an ECG at home. If the symptoms persist and you’re still worried, we always advise that you should book an appointment with your physician.