What is atrial fibrillation (AFib)?
Atrial fibrillation (AFib) is a type of heart arrythmia that causes the upper part of the heart to beat quickly and erratically. The main job of this part of the heart is to push blood into the lower section of the heart and then out to the body. AFib can slow the passage of blood to the lower section of the heart.
Blood also can become trapped and pool in the upper heart, increasing the risk of blood clots and stroke.
How is AFib diagnosed and treated?
If AFib is suspected, an electrocardiogram or holter monitor can be used to confirm the diagnosis. Catheter ablation is a procedure performed to treat some types of arrhythmia, including AFib, and often is recommended for symptomatic patients if AFib cannot be controlled with medications.
In a typical catheter ablation procedure:
- The doctor makes a needle puncture through your skin and into the blood vessel in your groin. A small straw-sized tube called a sheath is inserted into the blood vessel. The doctor gently guides a catheter (a long, thin tube) into your vessel through the sheath. You may feel some pressure, but should not feel any pain.
- The doctor inserts several long, thin tubes with wires, called electrode catheters, through the sheath and feeds these tubes into your heart.
- To locate the abnormal tissue causing arrhythmia, the doctor sends a small electrical impulse through the electrode catheter. This activates the abnormal tissue that is causing your arrhythmia. Other catheters record the heart’s electrical signals to locate the abnormal sites.
- The doctor places the catheter at the exact site where the abnormal cells are located inside of your heart. A mild, painless, radiofrequency energy, similar to microwave heat, is sent to the tissue. This ablates, or destroys, the abnormal heart muscle cells in a small area (about 1/5 of an inch) that are causing the rapid heartbeat.
- Catheter ablation usually takes between 2 and 4 hours. If you have more than 1 area of abnormal tissue, the procedure may take longer. Patients usually go home the same day, or may stay overnight.
What is the advantage of fluoroless catheter ablation?
In the traditional cardiac ablation procedure described above, a fluoroscopy technique uses x-rays to show real-time images of the heart on a video screen. This aids the physician in guiding the catheters to the site of the abnormal cells within the heart. Unfortunately, the radiation exposure from those x-rays can be significant and has been shown to increase the likelihood of developing a malignant cancer. The risk is to both the patient and their healthcare team.
As an alternative to x-ray images, fluoroless catheter ablation uses other electrophysiology techniques to guide surgeons in performing the ablation procedure. Dr. Saumil R. Shah, of Virginia Arrhythmia Consultants in Richmond, Virginia, is one of the first surgeons in the country to adopt fluoroless cardiac ablation as a safer alternative both for the patient and their healthcare team. “It is cutting-edge technology,” says Shah. “It means that we are performing the same procedures and maintaining the highest quality without exposing the patient, physician, or staff to x-ray radiation.”
3D electro-anatomic mapping and intracardiac echocardiography are types of non-invasive electrophysiology techniques that help guide the surgeon during fluoroless catheter ablations. Used together, they mimic the imagery created by an x-ray, but without the risk of radiation exposure. An echocardiogram uses sound waves (ultrasound) to create a picture of the heart as an alternative to x-ray images. A miniaturized probe called a transducer is advanced inside the heart and produces sound waves that bounce off of the heart and “echo” back to the probe. These waves are transformed into pictures that are seen on a video monitor.
According to some experts, the use of fluoroless catheter ablation should become the standard of care in the field of cardiology. A Weill Cornell Medicine and New York-Presbyterian study recently published in Heart Rhythm Journal found that, “The amount of fluoroscopy received by a patient during a routine [atrial fibrillation] ablation procedure is estimated to be the equivalent of the dose of radiation a patient would receive with 830 X-rays.”2 Electrophysiology techniques, like 3D mapping and intracardiac echocardiography, are a safer way to achieve the same result, without exposure to potentially harmful radiation.
Sources:
- American Heart Association (AHA).
- Heart Rhythm Journal. “Fluoroless catheter ablation of atrial fibrillation”. Lerman, MD, FHRS, Bruce B.; Markowitz, MD, FHRS, Steven M.; LIU, MD, FHRS, Christopher F.; Thomas, MD, George; Ip, MD, James E.; Cheung, MD, FHRS, Jim W. (Division of Cardiology, Department of Medicine, Cornell University Medical College, New York Presbyterian Hospital, New York, New York). June 2017, Volume 14, Issue 6, Pages 928–934.
- Heart Rhythm Case Reports. “Long-standing persistent atrial fibrillation ablation without use of fluoroscopy in a patient with cor triatriatum”. Saumil R. Shah, MD, Guru P. Mohanty, MD, David M. Gilligan, MD, FHRS, C. Mark Newton, MD, Virginia Cardiovascular Specialists, Chippenham Hospital, Richmond, VA. February 2019, volume 5, Issue 2, pages 88-92.