You have been diagnosed as having a fast / irregular heart rhythm and one of the chosen treatments is a procedure called DC Cardioversion. Some abnormal heart rhythms cause your heart to pump inefficiently and may put you at increased risk of developing a blood clot. This clot could lodge in the circulation and block blood flow, putting you at an increased risk of a stroke or other complications.
What is a DC Cardioversion?
Electrical DC Cardioversion is a long established technique for attempting to restore the heart’s normal rhythm by applying a brief electric shock to the chest wall, under light anaesthetic. This small electric shock is delivered through two pads on the chest. Although the procedure takes only a few seconds to perform, you will be asleep for 10 – 15 minutes or less.
The drugs to put you to sleep will be administered through a small needle (cannula) that the doctor or nurse will insert into your arm or hand on your admission.
To minimise the risk of stroke during the procedure you will have been stabilised on Warfarin before being admitted. You should have been taking Warfarin for at least 6 – 8 weeks prior to coming in for the procedure and your INR result should be above 2 continuously.
Some patients may be on other blood thinning drugs called Dabigatran – Pradaxa, Eliquis – Apixaban or Xarelto – Rivaroxaban / Edoxaban which also minimises the risk of stroke during the procedure. Please note failure to take this medication for 4 – 6 weeks continually will mean your DCCV will be cancelled.
On the day prior to your admission, you will be asked to attend the Pathology Lab at the hospital for a blood test.
It is very important that both the I.N.R. (a measure of how thin your blood is) if you are on Warfarin and other blood chemicals are within acceptable limits for the procedure to be carried out.
On occasions, it may be necessary to cancel the procedure at short notice if your blood tests are not range. This is done purely for safety reasons. We will try to re-book the procedure again as quickly as possible.
Fasting for the Procedure
Please ensure that you have fasted prior to your admission. You can have:
- Clear fluids (e.g. water, squash, tea without milk, coffee without milk) only until 06:30
- Solid food and milk should not be taken after 02.30
- No chewing gum, fizzy drink or smoking on the day of Cardioversion
If you do not fast as above this may cause your cardioversion to be delayed or cancelled.
You will be advised at pre-assessment about medications to omit or take. If you are taking Digoxin tablets, you will need to stop taking these 48 hours prior to admission. Diabetics should omit their insulin or diabetic tablets on the morning of the procedure but all other tablets (including Warfarin and other blood thinners) must be taken. Water tablets to be withheld that morning.
You will be required to come into the Cardiology Day Case Unit for the day. On admission you will be shown to your bed area and asked to remove your outer clothing and put on a hospital gown.
A nurse will then ask you some questions and complete your nursing records. You will have an E.C.G (heart tracing) recorded and the nurse will also check your temperature, pulse and blood pressure. Your ECG maybe found to be normal
therefore your procedure maybe cancelled. You will be spoken to by the Arrythmia Specialist nurse.
A doctor / nurse will also come and talk to you and explain the procedure. The anaesthetist may also want to examine you and ask you some further questions.
You will be asked to sign a consent form to confirm that you understand and agree to have the procedure. You will be given a copy of the consent form to keep.
The needle (cannula) will be inserted into one of your veins, usually in the back of the hand or forearm to administer the anaesthetic drugs to make you sleep.
You will be taken to a procedure room for the procedure and once you are asleep, an electric current from a defibrillator machine will be administered to the chest wall, aiming to revert the abnormal heart rhythm back to normal.
Will it work?
There is about a 90% chance that this procedure will return your heart rhythm to normal at the time.
However, depending on the underlying condition and your drug treatment there is a possibility that even if successful you may revert to your original rhythm within hours, days or weeks after the procedure. If unsuccessful, you may remain in your current rhythm and your medication would need to be continued or adjusted.
Will it hurt?
Since you will be asleep you will not feel the electric shock. You may, following the procedure, feel some skin irritation / soreness around where the pads have been and it is possible that your skin may become reddened.
The degree of discomfort experienced following a DC Cardioversion is variable. If you are not allergic to them, simple pain killers such as paracetamol may also help.
Are there any alternatives to DC Cardioversion?
The alternatives to DC Cardioversion should have been discussed with you by the Doctor who put you on the waiting list. Alternative treatment usually involves starting different medication in attempt to correct your heart rhythm.
This sometimes works alone and may be tried prior to bringing you into hospital for DC Cardioversion. If this is the case, an electrocardiogram will be recorded on admission to check your heart rhythm has not returned to normal. Not all patients benefit from medication alone, if this is the case it will be explained to you at the time you are put on the waiting list.
Are there any risks?
There are risks associated with this procedure which should have been discussed with you when the decision was made to put you on the waiting list for DC Cardioversion and will be discussed when taking your consent for the procedure.
However, if you have any concerns please do not hesitate to discuss them with your nurse at the pre assessment clinic / or on the day of your admission.
The recognised risks associated with the procedure:
- Dislodgment of a clot from within the heart. This can cause stroke, risk <1%
- Pulmonary oedema: fluid on the lung. May require treatment with medication
- Arrhythmias: fast or slow heart rhythm abnormalities. May require active treatment with medications or temporary pacemaker to correct
- The procedure can sometimes worsen arrhythmias. Rarely, it can cause life threatening arrhythmias
- Low blood pressure following the procedure which usually reverts to normal without treatment required
- Minor skin burns
If you have any concerns regarding the potential risks of this procedure then please do not hesitate to discuss this on the day of your admission.
Furthermore, if you have any questions concerning your general anaesthetic please feel free to discuss them with the anaesthetist attending to you.
It can be helpful to some people to write down their questions, as it is common to forget them when in hospital.
After the Cardioversion
After the cardioversion you will be sleepy for approximately 30 minutes. During this time, a nurse will monitor your blood pressure, pulse and oxygen level and you will be attached to a heart monitor to enable the nurse to see your heart rhythm, an electrocardiogram (ECG) will also be taken.
Do I have to stay on anticoagulation?
After successful Cardioversion anticoagulation will be continued for a period of time specified by your consultant. However it is most likely to be a long-term medicine that you will have to take.
Please make arrangements for someone to drive you to the hospital and also to collect you afterwards, as due to the effects of the anaesthetic, you will not be allowed to drive yourself home. It is also recommended that you do not use public transport on the day.
Advice for Patients on Discharge following DC Cardioversion
Please read this information COMPLETELY.
You have undergone a procedure whereby you have been given an intravenous anaesthetic.It is important you follow the following advice when you are discharged:
- You will need someone to stay with you at home for the rest of the day and overnight
- You must not drive your car for at least 24 hours after the procedure. Do not sign legal documents for at least 24 hours after the procedure
- On discharge, please go straight home and please rest for the remainder of the day. DO NOT EXERT YOURSELF IN ANY WAY FOR AT LEAST 24 – 48 HOURS
- You may eat and drink as normal
- If your chest is soreness due to the electrical current passing through your chest causing a slight irritation or a slight reddening of the skin on the chest that might sting like sunburn for a day or two. Unless you are allergic, please take regular painkillers such as paracetamol. If the pain / soreness persists for more than 48 hours contact your GP
When can I go home?
You may go home 3 to 5 hours after the procedure, providing everything is okay. On very rare occasions you may have to stay overnight so please ensure that you bring an overnight bag. The needle (cannula) which was inserted will be removed and a small dressing applied.
Prior to your discharge from the Cardiology Day Case Unit, you will be advised about your medication and follow up appointment (usually in four to eight weeks). If you require any new medication you will be given a 7 – 14 day supply. After this, you will need to see your own doctor for a repeat prescription.
You should contact your GP if you feel any changes in your heartbeat. If your arrhythmia has come back after your cardioversion procedure, you may have to return to have the procedure repeated or alternative treatments to restore it.
When can I go back to work?
You are able to return to work after 24 – 48 hours. You will be given a copy of your discharge letter. A letter will also be provided for your G.P. You should not need to make an appointment to see your doctor unless advised to on discharge. If you require any further advice about any issues concerning the procedure, please do not hesitate to call the Cardiology Day Case Unit where your procedure was performed. We are happy to answer any questions that you may have.
Should you require further information regarding heart investigations you may find the following websites useful:
The British Cardiac Society www.bcs.com
The British Heart Foundation www.bhf.org.uk
The British Society of Echocardiography www.bsecho.org
Contact Details for Further Information
If you have any queries regarding any of the information contained within this leaflet, or your admission date and time please contact the Unit carrying out the procedure at:
Diana, Princess of Wales Hospital, Grimsby on: 03033 306081 (Cardiology Day Case Unit)
03033 303058 (C1Glover)
Scunthorpe General Hospital on: 03033 302366 (Coronary Care Unit)
03033 302327 (Planned Investigations Unit)
Any Comments, Compliments, Concerns or Complaints
If you have any other concerns please talk to your nurse, therapist or doctor. Our Patient Advice and Liaison Service (PALS) is available on 03033 306518 (Grimsby, Scunthorpe and Goole). You can also contact nlg-tr.PALS@nhs.net
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Date of issue: January 2021
Review period: January 2024