At a glance
Cardioversion is a medical procedure that resets an abnormal heart rhythm back to a normal one by delivering a precisely timed electrical shock to the heart.
The heart beats because electrical signals move through it in an orderly pattern. When that pattern breaks down, the heart may beat too fast, too slow, or chaotically. Cardioversion sends a brief pulse of electricity through the chest wall and into the heart muscle, interrupting the faulty signals and giving the heart's own natural pacemaker a chance to take over and restore a steady rhythm.
Medical Condition
Cardioversion is used when the heart is beating in an abnormal rhythm, known as an arrhythmia, that has not responded to medication or that is causing serious symptoms such as breathlessness, chest pain, or faintness.
- Atrial fibrillation (AF), where the upper chambers of the heart quiver instead of beating properly, is the most common reason for cardioversion.
- Atrial flutter, a fast but more organised rhythm in the upper chambers.
- Supraventricular tachycardia (SVT), a rapid heartbeat that starts above the lower chambers.
- Ventricular tachycardia (VT), a dangerously fast rhythm in the lower chambers, when the patient still has a pulse.
Cardioversion is not suitable for everyone. Your cardiologist will review your full medical history before recommending it.
- Patients who have had AF for a long time without treatment may have a higher risk of blood clots being dislodged by the procedure.
- Certain abnormal rhythms caused by digoxin toxicity (a reaction to a specific heart medication) are generally not treated this way.
- People with very advanced heart disease or a sick sinus syndrome (a fault in the heart's natural pacemaker node) may need a different approach.
- The procedure is postponed if blood thinner medication levels are not within a safe range.
Risks & Complications
Cardioversion is generally considered a low-risk procedure, but like all medical interventions it carries some recognised complications.
- Skin redness or mild burns at the sites where the electrode pads are placed, which usually heal on their own within a few days.
- Brief period of low blood pressure immediately after the shock, which the medical team monitors closely.
- The arrhythmia returning hours, days, or weeks later, which is the most common longer-term issue.
- Dislodgement of a blood clot from the heart, which can travel to the brain and cause a stroke. This risk is why doctors require blood thinners to be taken beforehand.
- A different or new abnormal rhythm appearing after the procedure, which the team can usually treat quickly.
- Temporary confusion or disorientation from the short sedation used, particularly in older patients.
- In rare cases, injury to the heart muscle. This is uncommon with modern equipment and careful technique.
Preparation & Procedure
Preparation usually begins days or even weeks before the procedure, not just on the morning it is performed.
Most cardiologists require the patient to take blood thinners for several weeks beforehand to reduce the risk of a blood clot being dislodged during the shock. In some urgent situations, an echocardiogram (ultrasound of the heart) may be done to check for clots inside the heart before the procedure goes ahead. Smoking and alcohol are best avoided in the lead-up period, as both affect how the heart responds to treatment.
On the day itself, patients are asked to stop eating and drinking, usually for at least six hours before the procedure, because a short sedative will be given. The care team will also review any regular medications and may ask the patient to pause or adjust certain ones.
Tests commonly ordered before cardioversion include:
- An electrocardiogram (EKG), which records the electrical activity of the heart and confirms the type of arrhythmia.
- Blood tests to check kidney function, electrolyte (salt and mineral) levels, and blood thinner levels.
- An echocardiogram to look at the heart's structure and check for clots, if not already done.
- Chest X-ray in some cases to rule out lung problems.
The procedure itself follows a consistent sequence, although the exact steps may vary slightly between hospitals:
- 1. The patient changes into a hospital gown and lies on a procedure bed.
- 2. EKG electrodes (small sticky patches) are attached to the chest, arms, and legs to monitor the heart continuously.
- 3. A small needle is placed into a vein in the arm or hand to give fluids and medication.
- 4. A sedative or light anaesthetic is given through the vein so the patient is asleep and feels nothing.
- 5. Adhesive electrode pads are placed on the chest and sometimes the back. These deliver the electrical shock.
- 6. The machine is charged and synchronised to the patient's own heartbeat using the EKG signal. This timing is what separates cardioversion from a defibrillation (emergency shock used in cardiac arrest).
- 7. The shock is delivered. The patient's muscles may contract briefly, but because of the sedation this is not felt.
- 8. The EKG is checked immediately to see whether the rhythm has returned to normal.
- 9. If the first shock is not fully effective, the doctor may repeat it at a higher energy setting.
- 10. Once the target rhythm is achieved, the sedative is allowed to wear off and the patient is moved to a recovery area.
Aftercare
Most patients spend a few hours in a monitored recovery area before going home the same day, although an overnight stay is sometimes arranged depending on the patient's condition and the hospital's practice.
- Heart rhythm monitoring continues for at least one to several hours after the procedure to catch any immediate recurrence of the arrhythmia.
- Driving is not permitted on the day of the procedure because of the sedative; a companion should be arranged in advance.
- Blood thinners are usually continued for several weeks after cardioversion, and sometimes long-term, to reduce stroke risk.
- Any skin redness under the electrode pads can be soothed with a mild moisturiser; the care team will advise on this.
- Strenuous physical activity is typically restricted for a short period, with the cardiologist setting the timeline based on the individual.
- A follow-up EKG or outpatient appointment is usually scheduled within a few weeks to confirm the rhythm has held.
- Ongoing medication to suppress the arrhythmia from returning is often prescribed alongside the procedure, and regular cardiology reviews are part of long-term management.
- Lifestyle adjustments such as limiting alcohol, managing sleep apnoea (interrupted breathing during sleep), and controlling blood pressure support a lasting result.
Cost & What Determines It
The cost of cardioversion varies widely depending on where it is performed, how urgently it is needed, and what additional care is required around it.
- Complexity of the arrhythmia: a straightforward first procedure costs less than a repeat cardioversion or one combined with other cardiac investigations on the same day.
- Hospital class and country: the same procedure performed in a private hospital in a major city, a public teaching hospital, or a specialist cardiac centre in another country can carry very different price tags.
- Setting: a planned, elective cardioversion in a day-procedure unit is typically priced differently from one performed as part of an emergency or inpatient admission.
- Length of stay: most patients are discharged the same day, but any overnight monitoring adds to the bill.
- Cardiac imaging: an echocardiogram done as part of the workup is sometimes bundled in and sometimes billed separately.
- Anaesthesia or sedation fee: the sedation used during cardioversion is usually administered by an anaesthesiologist, whose fee may be separate from the procedural fee.
- Blood tests and EKG monitoring: pre- and post-procedure tests are sometimes included in a package and sometimes itemised.
- Ongoing medication: blood thinners prescribed for weeks before and after the procedure represent an additional cost outside the procedure itself.
Hospital packages for cardioversion often include the procedure room fee, nursing care, sedation, and basic monitoring. Items that are commonly billed separately include the cardiologist's consultation fee, echocardiography, blood tests, and any medications dispensed to take home.
For Indonesian patients, BPJS Kesehatan and most domestic private insurance policies do not cover treatment received abroad. Patients who choose to have cardioversion overseas typically pay out of pocket or hold an international private health insurance policy that explicitly covers planned cardiac procedures. Before travelling, asking the hospital for a written cost estimate that itemises each component is the practical way to understand the full financial commitment and avoid unexpected charges on discharge.
Frequently Asked Questions
How many sessions of cardioversion will I need?
Most patients need only one session, though some may need it repeated if the abnormal heart rhythm returns. Your cardiologist will monitor your heart rhythm after the procedure and decide whether a repeat session or a change in ongoing medication is appropriate.
Does cardioversion hurt? What does it feel like?
You will be given a short-acting sedative so you are asleep during the electric shock, meaning you should not feel any pain during the procedure itself. Afterwards, some people notice mild chest soreness or a flushed feeling on the skin where the pads were placed, but this usually fades within a day.
How soon will I know if cardioversion worked?
Your care team can tell immediately whether your heart has returned to a normal rhythm, because they watch your heart tracing on a monitor throughout the procedure. Even if the rhythm corrects right away, your doctor will usually keep you on blood thinners and heart-rhythm medication for some time afterward to reduce the chance of the rhythm slipping back.
How much does cardioversion cost?
The cost depends on factors such as the hospital's class and facilities, the length of monitoring required before and after the procedure, and the type of sedation used. Requesting a written cost estimate directly from the hospital is the most reliable way to get an accurate figure for your situation.
This page is general information, not a substitute for medical advice. Every case is different. Your doctor decides what is right for you.
