New treatment for atrial fibrillation (AFib) proving safe and effective
Atrial fibrillation, also known as AFib, is the most common abnormal heart rhythm and increases in prevalence with age. It affects up to 5% of the population older than 69 years, and 8% of the population older than 80 years.
In the heart of a healthy person, electrical impulses are sent from a group of cells called the sinus node in the upper right chamber of the heart (atrium). The signal spreads to the upper left chamber, down between the two lower chambers (ventricles), and then to the lower chambers. This ‘spreading’ of the electrical impulse is what makes our heart beat normally so that blood can be pumped into the lungs and throughout the body.
In the case of AFib, the atria (both upper chambers of the heart) beat chaotically and irregularly, and are out of coordination with the two ventricles. This means that the heart is not adequately supplying oxygen-rich blood to the body.
Although AFib itself usually isn't life-threatening, it is a serious medical condition that sometimes requires emergency treatment and can lead to complications. It may lead to blood clots forming in the heart that may circulate to other organs. When this happens, a person has a five times higher risk of stroke, in addition to other serious conditions as such congestive heart failure.
Often, patients do not feel anything and so will not know that something is wrong. Other patients can experience such symptoms as dizziness, chest pain, shortness of breath, faintness or a recognizable fluttering in the chest. Risk factors include hypertension, obesity, sleep apnea, diabetes and lung disease. The cause can also be unknown, and called ‘lone AFIB’.
AFib can be brief and happen only occasionally or can be recurrent. This is called “Paroxysmal fibrillation.” This is unpredictable and can turn into the more serious “Persistent AFib,” where the heart cannot be returned to a normal rhythm without treatments that help control symptoms and prevent future complications.
There are several tests used to diagnose AFib, including an electrocardiogram (EKG), and a monitor you can wear that records the heart rate and rhythm over 24 to 48 hours or even up to 4 weeks. If AFib is such that treatment is required, there are many different medications that can regulate or control the rhythm and rate of the heart, or that can prevent the formation of blood clots to avoid stroke and other complications.
While people can live a long time with AFib, finding the right treatment regimen for each individual patient can be challenging. Unfortunately, drug therapy fails in half of patients and further treatment using catheter ablation is required. One new ablation treatment proving to be safe and more effective than medication in clinical studies is catheter cryoablation. In fact, studies show that more than 70% of patients treated with catheter cryoablation were free from AFib after one year, compared to less than 10% of patients treated with medication.
Cryoablation is performed in an electrophysiology (EP) lab, such as we have at Beebe Healthcare, by an experienced electrophysiologist, which is a cardiologist specializing in treating all types of heart rhythm disorders. It is a minimally invasive procedure that allows the electrophysiologist to restore a normal heartbeat by using extreme cold (cryo) to destroy or damage abnormally firing tissue by freezing. The electrophysiologist inserts a balloon catheter into a blood vessel, usually in the upper leg, and then threads it though the body until it reaches the heart. Once the balloon is in the correct position, extremely cold energy is sent though the catheter to freeze the tissue.
In the EP lab at Beebe Healthcare, we use advanced technology called 3-D mapping that allows me to create an electro-anatomic map (real-time geometry) of the heart. The image is displayed on a monitor so that I can use it as a guide as I perform the procedure. I began performing catheter cyoablation this year at Beebe and it is already showing very good results and offers hope that we can help patients control this heart problem.
Firas El-Sabbagh, MD, is a cardiac electrophysiologist with offices in Millsboro and Lewes and Medical Director of Electrophysiology Services at Beebe Healthcare.