CARDIOVERSION

​

Cardioversion is a medical procedure used to restore a normal heart rhythm in patients with certain types of abnormal heartbeats, or arrhythmias. The most common arrhythmias treated with cardioversion are atrial fibrillation and atrial flutter. The procedure can be performed using electrical or pharmacological methods.

​

1. Electrical cardioversion: This method involves delivering a controlled electric shock to the heart through electrodes placed on the patient's chest. The shock momentarily stops the heart's electrical activity, allowing the heart's natural pacemaker to regain control and restore a normal rhythm. Electrical cardioversion is performed under sedation or short-acting general anesthesia to ensure the patient's comfort.

2. Pharmacological cardioversion: This method involves using antiarrhythmic medications to restore a normal heart rhythm. These medications can be administered orally or intravenously, depending on the patient's condition and the specific drug used. Pharmacological cardioversion may be used in cases where electrical cardioversion is not appropriate or has not been successful.

​

Effective depolarization of a critical mass of the heart terminates the arrhythmia, allowing normal sinus rhythm to resume. The pulse is delivered synchronously to the QRS,

​

Before the procedure, the patient will undergo a thorough evaluation, including a review of medical history, a physical examination, and diagnostic tests such as an electrocardiogram (ECG) or echocardiogram. The physician may also prescribe anticoagulant medications for several weeks before and after the procedure to reduce the risk of blood clots and stroke.

​

After the procedure, the patient will be monitored to ensure that the heart rhythm has returned to normal and that there are no complications. The healthcare team may prescribe medications to help maintain a normal heart rhythm and reduce the risk of future arrhythmias. 

​

                                                                                                 

                                                                Anesthetic Implications for Cardioversion

​

Anesthesia type: Brief general anesthesia, deep sedation

​

Airway: ETT rarely needed

​​

Preoperative:

​​

• Adequate anticoagulation in patients with AF

• Assess the presence or absence of hemodynamic instability

• In the emergency patient, full-stomach precautions may be needed​

• Elective cardioversions are often performed on patients who have failed drug therapy

• Assess the presence of CAD, CHF, and valvular disease

• Have emergency airway equipment, oxygen, suction, and resuscitation medications

• Cardioversion is painful, ensure adequate sedation

• TEE/ECHO can help detect left atrial appendage thrombus

• If a thrombus is identified, cardioversion is canceled

• Ensure the patient is NPO and not a full stomach

• Ensure the head of the bed is easily accessible in case of airway compromise

• Stay clear of the patient prior to the delivery of synchronized shock

​

Intraoperative:

​

• Maintain a patent airway and limit apnea

• Duration < 30 minutes

• Position: Supine with defibrillator pads

• No blood loss

• Profound bradycardia can occur after cardioversion

​

Postoperative:

​

• Monitoring of cardiac rhythm

• Check for full recovery of airway reflexes

• Perform neurological exam

​

Complications:

​

• Stroke

• Embolic event

• Skin burns (thermal injury)

• New arrhythmias

• Acute pulmonary edema

• Loss of airway

• Severe bradycardia

• Hypertension

• Catecholamine surge

• Myocardial ischemia

• Recall/awareness

• Myalgias

​

​

Sources:

 

Jaffe, R. A. (2020). Anesthesiologist's Manual of Surgical Procedures (6th ed.). 

​

​

​

​

​

​

 

​​

​​