Understanding Medication Management for Cardioversion
Cardioversion is a medical procedure used to restore a normal heart rhythm in people with certain types of abnormal heartbeats (arrhythmias), such as atrial fibrillation (AFib). The success and safety of this procedure are significantly influenced by the patient's current medications. While some drugs can interfere with the procedure or increase risks, others, particularly anticoagulants, are essential for preventing serious complications like stroke [1.5.1]. Current guidelines recommend at least three weeks of therapeutic anticoagulation before cardioversion and four weeks after for patients with AFib lasting more than 48 hours or of unknown duration [1.8.4]. This is because the risk of a thromboembolic event (a blood clot traveling through the bloodstream) is highest within the first week after cardioversion [1.5.1].
Medications Typically Stopped or Held
Healthcare providers give specific instructions on which medications to hold before the procedure. This is often done to prevent adverse interactions with the anesthesia used or to minimize risks associated with the electrical shock itself.
- Digoxin: It is a long-standing practice to withhold digoxin for 24 to 48 hours before an elective cardioversion [1.2.3, 1.2.2]. Early reports indicated that in the presence of digoxin toxicity, direct current (DC) cardioversion could provoke lethal ventricular arrhythmias [1.4.5]. While some studies suggest cardioversion is safe in patients with therapeutic, non-toxic digoxin levels, the standard precaution is to stop the medication to avoid the increased risk of post-shock arrhythmias [1.3.5, 1.4.3].
- Certain Diabetes Medications: Patients are generally instructed to hold diabetes medications the night before or the morning of the procedure [1.2.1]. This is especially important for specific classes of drugs due to the fasting period (NPO) required before receiving sedation.
- SGLT2 Inhibitors: Drugs like Jardiance, Farxiga, and Invokana need to be stopped for at least three days (or three doses) before the procedure [1.2.1, 1.2.4].
- GLP-1 Agonists: Medications such as Ozempic, Trulicity, and Wegovy should be stopped for one dose before the procedure [1.2.1].
- Insulin: The night before the procedure, a half dose is often recommended, with no insulin taken on the morning of the cardioversion [1.2.1].
- Diuretics: Some instructions may include holding diuretics on the morning of the procedure.
Medications Typically Continued
Not all medications are stopped. Many are crucial for the patient's stability and the procedure's success. Patients should always take their regular medications with small sips of water unless explicitly told otherwise by their provider [1.3.1].
- Anticoagulants (Blood Thinners): This is the most critical class of medication to continue. Patients are explicitly instructed NOT to stop their blood thinner (e.g., warfarin, Eliquis, Xarelto, Pradaxa) unless directed by their provider [1.2.1]. Adequate anticoagulation for at least 3-4 weeks prior to the procedure is a cornerstone of preventing stroke [1.3.6]. The development of direct oral anticoagulants (DOACs) has made this process more predictable than with warfarin, which requires frequent monitoring to ensure a therapeutic level (INR of 2.0-3.0) [1.8.3, 1.5.6].
- Beta-Blockers and Calcium Channel Blockers: While some institutions recommend holding drugs like metoprolol or diltiazem on the morning of the procedure, others specifically instruct patients to continue taking their beta-blockers (e.g., bisoprolol, carvedilol) [1.2.1, 1.2.2]. Pre-treatment with beta-blockers may even improve the rate of maintaining a normal sinus rhythm after cardioversion [1.9.2]. The decision rests with the treating physician and institution protocol.
- Other Antiarrhythmic Drugs: Aside from digoxin, other antiarrhythmic drugs may be continued. In some cases, pretreatment with agents like amiodarone, flecainide, or sotalol can decrease the energy required to restore sinus rhythm and reduce the risk of early AFib recurrence [1.2.3].
Medication Decision Comparison Table
| Medication Class | Common Examples | Typical Pre-Cardioversion Instruction | Rationale |
|---|---|---|---|
| Anticoagulants | Warfarin, Apixaban (Eliquis), Rivaroxaban (Xarelto) | CONTINUE without interruption [1.2.1] | To prevent blood clots and reduce stroke risk, which is elevated around the time of cardioversion [1.5.1]. |
| Digitalis Glycosides | Digoxin (Lanoxin) | STOP 24-48 hours before procedure [1.2.2, 1.6.5] | To reduce the risk of provoking serious ventricular arrhythmias, especially if toxicity is present [1.4.5]. |
| Beta-Blockers | Metoprolol, Bisoprolol, Carvedilol | Varies: Often continued, but sometimes held morning of [1.2.1, 1.2.2] | Can help with rate control and may improve long-term success of maintaining normal rhythm [1.9.2]. Decision is provider-dependent. |
| SGLT2 Inhibitors | Jardiance, Farxiga, Invokana | STOP 3 days before procedure [1.2.4] | To mitigate risks associated with the required fasting period before anesthesia. |
| GLP-1 Agonists | Ozempic, Trulicity, Wegovy | STOP for one dose before procedure [1.2.1] | To manage risks related to anesthesia and slowed gastric emptying during a fasting state. |
| Other Antiarrhythmics | Amiodarone, Sotalol, Flecainide | Generally CONTINUE [1.2.3] | Can help facilitate conversion to and maintenance of normal sinus rhythm [1.2.3]. |
Conclusion
Deciding what medications should be stopped before cardioversion is a critical safety step managed by the cardiology and anesthesiology teams. The most consistent and important instruction is to continue taking prescribed anticoagulants to prevent stroke [1.3.4]. The decision to temporarily stop other medications, most notably digoxin and certain diabetic drugs, is based on minimizing procedural risks and potential adverse effects [1.2.1, 1.3.2]. Patients must follow the specific instructions provided by their healthcare team, as protocols can vary slightly between institutions. After the procedure, medication regimens are often adjusted, with anticoagulation continuing for at least four weeks and sometimes lifelong [1.8.1].
For more detailed patient instructions, consider visiting the Cleveland Clinic's patient guide on cardioversion.
