When your heart beats irregularly or seems to stop: what is it and do you need tests?

AFib Matters (a website prepared by the ESC and EHRA for patients) describes palpitations, that is, feeling your heartbeat, like this: the heart may beat harder or faster, be irregular, and beats may feel skipped, “dropped” or uneven. Less often, a very fast “fluttering” is felt. Such episodes may come and go. However clear the sensation is, it is not a diagnosis.

Extrasystoles are extra (ectopic) beats that come earlier than expected. AFib Matters lists such beats among the causes of feeling your heartbeat. Extra beats that come from the ventricles are called premature ventricular contractions (PVCs). Extra beats are often harmless, but only tests can tell whether that is so in your case.

Yes. Among the causes, AFib Matters lists ordinary situations (feeling your heartbeat after exercise, excitement or an infection), anxiety, caffeine and other conditions not related to the heart, as well as other arrhythmias. Alcohol and caffeine may be triggers.

In atrial fibrillation, the rhythm is “completely irregular” (the AFib Matters term: irregularly irregular), and episodes may come and go. Feeling your pulse may make you suspect irregularity, but it cannot reliably confirm it, especially when the heart is beating fast. That is why the cause has to be found with an ECG, not by how it feels.

According to AFib Matters, seeing a doctor is needed especially when it comes together with dizziness, chest pain or shortness of breath. Fast episodes that interfere with daily life, as well as episodes with shortness of breath, dizziness, fainting or chest pain, require urgent medical help.

To prepare for your appointment, keep a symptom diary: how long it lasted, what triggered it, what else you felt. Even if the symptoms seem harmless, if they keep coming back, have a planned check-up.

According to AFib Matters, if the heart beats irregularly all the time, an ECG at rest helps make the diagnosis. If episodes come and go, the main thing is a recording taken during the symptoms. According to the BC Guidelines, the method depends on how often the symptoms occur:

• if almost every day, 24–48 hour Holter monitoring;
• if less often and unpredictable, an external event recorder that you switch on during symptoms, for up to about a month;
• if less than once a month, a small loop recorder placed under the skin, for up to about 3 years; this is an invasive method.

The guideline also notes that when symptoms are rare, repeating the Holter may not help. The doctor decides which method is needed.

Whether treatment is needed and which method, the doctor decides based on where the extra beats come from, whether they cause symptoms and how many there are. According to the ACC summary of the 2022 ESC guidelines:

• for extra beats with symptoms that come from the right ventricular outflow tract or from the conducting fibers in the left ventricle, catheter ablation is recommended as the first choice;
• if they come from other places and cause symptoms, beta-blockers or non-dihydropyridine calcium channel blockers may be used; sometimes flecainide or ablation is also considered.

If there are very many extra beats, that is, they make up 10 % or more of all beats, and the pumping strength of the heart (ejection fraction) has dropped for no clear reason, the guideline recommends taking into account that this drop may be caused by the extra beats themselves and considering a cardiac MRI. If the cardiomyopathy is likely to have been caused by frequent, mostly same-shaped (monomorphic) extra beats, ablation is recommended. Do not choose a medicine or a procedure on your own.