Cardioversion for Atrial Fibrillation (AF) with Rivaroxaban
AF can cause palpitations, breathlessness, tiredness and inability to exercise. Patients found in AF are often offered ‘cardioversion’ to try and restore normal rhythm. This involves applying a high voltage shock to the heart under general anesthetic. This is very controlled and the risks are very low if managed properly.
A major problem with AF is the ‘stagnation’ of normal blood flow in the atria, which can lead to the formation of blood clots. If these clots subsequently dislodge and are released into the blood stream, there is a serious risk of ‘thrombo-embolism’ and stroke when the blood clots reach the brain. This is particularly relevant when performing cardioversion when the heart is suddenly transformed form irregular fibrillation back to normal rhythm. Pre-treatment with blood thinning drugs is required to prevent a thrombus (blood clot) forming for at least 3 weeks before and for at least a month afterwards, although for the majority of people with AF these drugs will need to continue indefinitely.
Trials are therefore being conducted to compare the different blood thinning drugs and their relative effectiveness as a pre-treatment for AF procedures.
The indications for using warfarin rather than one of the novel oral anticoagulant drugs (NOACs) are diminishing. Data from the X-Vert Study published in the European Heart Journal confirm that performing electrical cardioversion for patients with atrial fibrillation taking rivaroxaban is just as safe and effective as for those taking warfarin.
The study showed that there was a 25% reduction in the time needed to wait from starting rivaroxaban (22 days) before cardioversion, as opposed to warfarin (30 days) and this was statistically significant.
However, Rivaroxaban, and the other NOACs, have the distinct additional advantage of not needing blood test monitoring and the complex dose adjustments that warfarin does. In other words, as London Cardiologist and AF expert Dr Oliver Segal explains, "if you see a doctor and are told you need a cardioversion and are taking rivaroxaban, you know this can be done safely twenty one days later. It is best to keep the next few weeks (or sometimes even months) open if you’re on warfarin."
Furthermore, the NOAC drugs don't interact with many other drugs, unlike warfarin, and have few interactions with food either, unlike warfarin. Their effects are predictable, unlike warfarin.
So, what's the down side? They are expensive and this has limited their prescription in the UK. In fact, the UK is the only country in the Western World where warfarin prescriptions are still actually rising!
There are three NOACs licensed for stroke prevention for patients with atrial fibrillation in the UK, these include:
- Rivaroxaban,
- Apixaban and
- Dabigatran
These drugs have now been used in tens of millions of patients world-wide and are slowly taking over from warfarin in the UK. The data from the X-Vert Study opens up an additional clinical area where rivaroxaban can be used to help patients with AF offering greater efficiency, no blood test monitoring and better quality of life.
