A heart rhythm study is a very common procedure.
A heart rhythm study enables your doctor to study your heart’s electrical activity, by placing electrodes inside your heart.
A heart rhythm study is useful for arrhythmias producing slow heart rates (bradycardia) as well as those producing fast heart rates (tachycardia).
If your arrhythmia is due to atrial fibrillation (an irregular, often rapid heart rate), a heart rhythm study combined with radiofrequency ablation (also known as cardiac ablation or catheter ablation) has a success rate of 70% to 80%. If you’re an older person with heart disease the success rate is lower.
The skill of your electrophysiologist plays a big part in the success of the procedure. An electrophysiologist is a cardiologist who has specialist training in heart rhythm studies.
Heart rhythm studies, which are often combined with ablation, are low risk procedures. The main risk is failure to fix the problem. For 20% to 30% of people with atrial fibrillation, a heart rhythm study combined with ablation doesn’t work the first time. A repeat procedure increases the rate of success by about 10%.
Apart from this, the risk of complications from a heart rhythm study is usually less than 0.5%.
The main risks and complications are:
Bleeding or infection
This can sometimes occur where the catheter was inserted in your groin.
Injury to blood vessels
Although it’s unusual, an injury to a blood vessel is the most common complication from a heart rhythm study. Occasionally the femoral artery, which is near the femoral vein in your groin, is punctured during the procedure.
Injury to the lining of the lung
It’s possible for your lung to be punctured by the catheter. This can cause air to leak out of your lung, and may require drainage of this air until the leakage stops. This complication can sometimes mean you have to spend a few extra days in hospital.
Puncture of the heart or damage to the heart valves
Occasionally a catheter damages the wall of the heart or a heart valve. However, this is extremely uncommon. It sometimes requires surgery to repair the damage.
Induction of severe arrhythmias
The goal of a heart rhythm study is to trigger and study your arrhythmia. Occasionally the procedure triggers a severe arrhythmia. You may feel dizzy or faint for a few seconds, but the equipment and medical team can usually manage this.
Damage to the heart’s electrical system
Your heart's normal electrical system could be damaged by the procedure. This is usually temporary, but if it persists you may need to have a pacemaker implanted.
Damage to your heart or nearby structures
Once the arrhythmia is identified, it’s often treated with radiofrequency ablation. This procedure creates a small burn to the area of the heart that’s causing the arrhythmia. Occasionally this damages other structures, like the veins bringing blood to your heart from your lungs or your swallowing tube (oesophagus).
Damage to the veins can cause them to narrow. In rare cases this leads to problems like cough and shortness of breath. Damage to the oesophagus has been known to create a hole between the heart and oesophagus.
Blood clots in your legs, lungs or heart
This can lead to stroke if the clot travels to your brain. If your doctor thinks you may be at risk, they’ll give you a blood-thinner.
Rarely, a heart rhythm study triggers a heart attack.