Restoring a normal heart rhythm: the pros and cons

Photo of a couple (PantherMedia / kurhan)

In atrial fibrillation, the rhythm of the heart is irregular and the heart usually beats faster than normal. The high pulse can be reduced with medications such as beta blockers. There are also treatments that aim to restore and maintain a normal heart rhythm. These are most suitable for people who have severe symptoms.

If someone has atrial fibrillation, trying to restore a normal heart rhythm (sinus rhythm) may sound logical at first. But even if this treatment works, sooner or later most people go on to develop atrial fibrillation again – sometimes without noticing it. And the treatments that are used to restore the sinus rhythm are associated with side effects and risks, including the risk of serious complications. So it is worth carefully considering the pros and cons of this treatment together with your doctor.

It's important to know that even if your heartbeat returns to a normal rhythm after treatment, you are still at higher risk of having a stroke. Because of this, people often still need to carry on taking anti-clotting medication (anticoagulants).

Lower your pulse or reset your heart rhythm?

Most people who have atrial fibrillation only have treatment to slow down their heartbeat. The aim of this treatment to control the heart rate is to reduce the heart’s workload and relieve bothersome symptoms. Beta blockers are typically used to lower the resting heart rate to less than 110 beats per minute at first. If that isn’t enough to relieve the symptoms, doctors can try to lower the resting heart rate further, either by using a higher dose of the same medication or using additional medications.

Another option is to try to restore the normal “sinus” rhythm, either with medication or by delivering a small electric shock. The medical term for this is pharmacological or electrical cardioversion. After cardioversion, people typically take medication to stabilize their heart rate (anti-arrhythmics) and ultimately prevent atrial fibrillation from recurring.

Arguments for having treatment to restore the heart rhythm

If this kind of treatment is successful, it has two main advantages: On the one hand, it reduces symptoms of atrial fibrillation. On the other, the performance of the heart returns to normal. Other reasons for getting treatment to restore the heart rhythm include:

  • Bothersome symptoms: For instance, if symptoms like palpitations or exhaustion don't go away enough after treatment to control the heart rate.
  • First-time, acute episode: If you have atrial fibrillation for the first time or if you haven’t had it for a long time. It is assumed that the chances of successfully restoring and maintaining the heart rhythm will then be higher.
  • Heart failure (cardiac insufficiency): If it is thought that atrial fibrillation is causing heart failure, treatment to restore the heart rhythm could help to improve the heart’s performance.
  • If atrial fibrillation is being caused by a treatable condition: If atrial fibrillation is being caused by another medical condition, such as an overactive thyroid gland, that underlying condition is treated first. Should the heart rhythm not return to normal on its own after that, cardioversion is attempted. If treatment for the condition that is causing the atrial fibrillation is effective enough, the heartbeat often remains stable over the long term afterwards.

There are sometimes other reasons to try cardioversion – for instance if the person is very sporty and finds it important to have their heart working at full capacity.

Arguments against having treatment to restore the heart rhythm

The main arguments against having this treatment are the associated risks and limited chances of success:

  • Associated risks: The medications that are used to restore the heart rhythm can themselves cause heart rhythm problems – some of which are life-threatening. Cardioversion also temporarily increases the risk of a stroke. When the heartbeat returns to the normal rhythm, any blood clots in the left atrium (upper heart chamber) might become dislodged and lead to a stroke. In the first few weeks after cardioversion there is also an increased risk of new blood clots forming in the heart. These risks can be lowered, but not completely eliminated, using preventive treatment with anticoagulants.
  • Limited chances of success: Although it is often possible to restore the normal heart rhythm through cardioversion, most people develop atrial fibrillation again after some time.
  • Limited advantages: Research has shown that – compared to treatment to control the heart rate – treatment to restore the heart rhythm doesn’t increase life expectancy, and doesn’t offer better protection from medical conditions caused by atrial fibrillation, such as strokes.

Treatment to restore the heart rhythm may also be less suitable

  • if the atrial fibrillation has persisted for more than one year: Cardioversion is then not likely to be successful.
  • in older age: It is a good idea for older people in particular to carefully consider the pros and cons of cardioversion because of the associated risks.
  • if atrial fibrillation has recurred: Cardioversion is less likely to be successful after the first attempt.
  • if you also have certain other medical conditions such as chronic kidney failure or other heart problems.
  • due to practical disadvantages: Treatment to restore the heart rhythm often involves more check-ups and medications to prevent atrial fibrillation from recurring.

A lot of people still have to take medication to control their heart rate after cardioversion. This is because some people still have a high pulse even after the rhythm of their heart has returned to normal.

How likely is it that treatment to restore the heart rhythm will be successful in the long term?

Many people who have had successful cardioversion develop atrial fibrillation again. According to studies, this happens within a year in up to 80 out of 100 people. The success rate can be improved somewhat by taking anti-arrhythmic medication over the longer term. But it is only rarely possible to stop the heart rhythm becoming irregular again at some point.

Anti-arrhythmics can cause a number of side effects when taken over a longer period of time. For instance, in 5 out of 100 people they cause heart rhythm problems that may sometimes be life-threatening. Other possible side effects include vision problems, increased skin sensitivity to light, as well as nausea, vomiting and diarrhea. The side effects go away again if you stop taking the medication.

Choosing a treatment strategy

The decision regarding whether or not to have treatment to restore your heart rhythm is ultimately a personal decision. It will depend on how you feel about the pros and cons of the treatment. Many medical societies only recommend cardioversion if other treatments aren’t effective enough.

It is best to talk with your doctor about which treatment strategy is suitable for you. Regardless of whether you decide to have treatment to control your heart rate or treatment to restore your heart rhythm, the decision won’t necessarily be “final”: Your situation may change over time, leading to a change in treatment strategy.

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