Cardioversion

What is it for?

You have an irregular heartbeat which means that the heart is not working as efficiently as normal. The irregular heartbeat may be making you less able to exert yourself or may be putting you at increased risk of complications such as stroke. We are going to try and make the heart beat regularly again by applying an electrical shock under general anaesthetic. This may be combined with drug treatment to help stabilize the heartbeat.

Are there any risks with this procedure?

Provided you have had appropriate treatment with anticoagulation (blood thinning treatment) before the procedure, there are no serious side effects from cardioversion. Sometimes the application of electrical energy to the skin of the chest causes minor reddening of the skin and soreness.

What needs to be done in preparation for cardioversion?

You should already have been started on the warfarin medicine to thin your blood and this treatment will need to be supervised in the anticoagulant clinic for at least a month before you will be ready for the cardioversion. Some patients may receive treatment with injected anticoagulant (low molecular weight heparin injected under the skin) before the procedure and for a period after the cardioversion.

Other medication may be added to your usual tablets before cardioversion (or repeat cardioversion) in order to increase the likelihood of success. The purpose of any additional medication and possible side effects will be explained to you before any change in medication.

How will I know when to come for the procedure?

The procedure will be scheduled for a mutually convenient day and time. We would normally confirm the arrangements in writing by post. Please let us know if the scheduled date for admission is inconvenient. Contact either your consultant's secretary or The Kings Oak Hospital (contact numbers at the end of this page).

What will I need to do to prepare for the procedure?

The cardioversion will be done as day-case procedure. Most patients will be able to go home later the same day but occasionally patients are kept in hospital overnight. The cardioversion will be done under general anaesthetic. The anaesthetic will probably only need to be short (a few minutes) but you will need to be prepared for the anaesthetic in the usual way. This means that your stomach must be empty (because of the risk of vomiting when having the anaesthetic). For cardioversions scheduled to take place in the morning, you should not eat and drink after midnight, except for a few sips of water with which to take your usual medication. If the procedure is scheduled for later in the day you should not eat or drink for at least 6 hours beforehand. Do not even take sweets or chewing gum in the period of fasting before the procedure.

What will I need to bring with me?

Please bring:

• A dressing gown, a set of nightclothes and any toiletries you may require;
• Any tablets or medicines that you may need to take during the day (and a list of the medicines you take regularly);
• Your anticoagulation card;
• Some reading material;
• A small bag to keep your things in;

What will happen when I come into hospital?

You should report to reception on arrival. There you will be asked to check and complete the details we hold on file about you. You will be seen by a nurse who will check your blood pressure and weight. We may need to record a heart tracing (ECG) to check your heart rhythm and sometimes a blood test is needed to make sure that your blood is thin enough for you safely to undergo the procedure.

You will be seen by your consultant who will perform the cardioversion, and also by an anaesthetist. The procedure will be explained to you and you will be asked to sign the consent form to give your permission in writing for the procedure to be undertaken. You will have an opportunity to ask any questions you may have about the procedure.

You will be escorted to the room where the cardioversion will be carried out and you will be given an anaesthetic. When you are fully anaesthetised you will undergo the cardioversion by means of special electrodes applied to the chest.

You will come out of the procedure room on a trolley into the recovery area. Your blood pressure and pulse will be monitored for a short while. You will then be returned to your room on the ward until you are ready to go home.

You may have a heart tracing (ECG) repeated before you are discharged.

When will I be ready to go home?

You will be allowed home as soon as you feel well enough after waking up from the anaesthetic but not before one hour after the procedure.

You will be discharged by one of the nursing staff and will not necessarily be seen by a doctor. You will be sent home with a letter for your GP which should be delivered to him/her within 48 hours.

Please remember that after going home you should have:

• An escort home in a private car or minicab;
• Access to a telephone at home;
• Someone with you for the first 24 hours after your anaesthetic;

When back at home you should rest and may sleep as much as you wish. You may eat and drink normally but should avoid alcohol and sleeping tablets for at least 24 hours. Simple painkillers (such as paracetamol or panadol) are allowed if you feel soreness where the electrodes were applied.

Will I have to come back to the outpatient clinic again?

We would normally arrange an appointment for you to be seen again in the consulting rooms approximately one month after your cardioversion. We will always try to make this appointment before you leave the ward.

What about my warfarin and my other medications?

You must continue your warfarin and continue to attend the anticoagulant clinic until you are told that you may stop.

Even after a successful cardioversion warfarin must be continued for at least a month.

You can expect to be given specific instructions about your other medication before you are discharged.

What should I do if I feel that my heart starts beating irregularly again after the cardioversion?

You should contact your consultant's secretary or The Kings Oak Hospital if you are concerned in any way after the procedure.

Further Information:

If you have any questions or concerns not covered by this leaflet, or if the scheduled date for your cardioversion is not convenient, please telephone either your consultant's secretary or The Kings Oak Hospital on 020 8370 9500.