DC cardioversion is a common medical procedure designed to restore a normal heart rhythm in individuals with abnormal heartbeats. This intervention manages various heart rhythm disorders, aiming to improve symptoms and reduce associated risks. Understanding the procedure can help demystify the process.
What is DC Cardioversion?
DC cardioversion uses a controlled electrical shock to reset the heart’s rhythm to a normal pattern. The “DC” refers to direct current, indicating the type of electrical energy delivered. This current temporarily depolarizes heart muscle cells, allowing the heart’s natural pacemaker to regain control and re-establish a healthy rhythm. This method differs from chemical cardioversion, which uses medications to achieve a similar outcome.
Synchronization with the heart’s electrical activity is a key aspect. The shock is precisely timed to occur during the QRS complex on an electrocardiogram (ECG). This prevents the shock from being delivered during a vulnerable period, which could lead to dangerous arrhythmias. Unlike defibrillation, which delivers a higher-energy, unsynchronized shock in emergency situations like cardiac arrest, DC cardioversion is typically a scheduled procedure for patients with a pulse.
Why It’s Performed
DC cardioversion treats specific heart rhythm disorders (arrhythmias) that cause the heart to beat too fast or irregularly. Primarily, it is used for conditions such as atrial fibrillation (AFib) and atrial flutter. In atrial fibrillation, the upper chambers of the heart (atria) beat chaotically and rapidly, while in atrial flutter, they beat very quickly in a more organized but still abnormal pattern.
These irregular rhythms can lead to various symptoms, including shortness of breath, fatigue, chest discomfort, and dizziness. Beyond symptom relief, restoring a normal rhythm also reduces the risk of serious complications like stroke. Stroke can arise from blood clots forming in the heart due to stagnant blood flow. The procedure’s goal is to enable the heart to pump blood more efficiently throughout the body.
Getting Ready for the Procedure
Preparation for DC cardioversion involves steps to ensure patient safety and effectiveness. Patients typically fast for several hours before the procedure, usually not eating or drinking after midnight or for at least eight hours prior. This is because the procedure is performed under sedation or light anesthesia.
Blood-thinning medications (anticoagulants) are a particularly important aspect of preparation. These are often prescribed for several weeks (commonly three to four) before cardioversion. This prevents blood clots from forming in the heart, as restoring a normal rhythm could dislodge existing clots and lead to a stroke. In some cases, a transesophageal echocardiogram (TEE) might be performed just before the procedure to check for any existing blood clots in the heart.
The Cardioversion Process
The DC cardioversion procedure is generally quick, often taking only a few minutes to complete. It is performed while the patient is under light sedation or a short-acting general anesthetic, ensuring they remain comfortable and do not feel the electrical shock. Medical staff continuously monitor the patient’s breathing and heart activity throughout the procedure.
Adhesive pads or paddles are placed on the patient’s chest, sometimes with one on the chest and one on the back. These pads are connected to a specialized machine that records the heart’s electrical activity. The machine then delivers a synchronized electrical shock, which lasts for less than a second, aiming to reset the heart’s rhythm. Following the shock, medical personnel assess the heart’s response to confirm if a normal rhythm has been restored.
Recovery and Next Steps
Following DC cardioversion, patients are monitored in a recovery area until sedation wears off, usually allowing for same-day discharge. It is common to feel sleepy or drowsy for the remainder of the day due to the anesthetic. Some individuals may experience mild skin irritation or soreness where the pads were placed, similar to a sunburn, which can last for a few days and may be soothed with lotions.
Patients are advised not to drive or operate machinery for at least 24 hours after the procedure. Continued medication, particularly blood thinners, is often recommended for several weeks post-procedure (typically at least four) to minimize blood clot risk. Follow-up appointments with the healthcare provider are scheduled to monitor the heart’s rhythm, adjust medications if needed, and discuss long-term management of the heart condition.