By Dr. Jignesh Shah
Normally, the heart beats steady and strong, pumping oxygen-rich blood throughout the body. Most of the time, we don’t even notice the regular, life-sustaining rhythm. However, when the heart beats faster than normal, or when the heart "skips a beat,” it can be quite unsettling.
As a cardiologist at the Gill Heart Institute at the University of Kentucky, I see a lot of patients with heart rhythm disorders. Here are some of the more common questions they ask.
Q: What are the different types of heart rhythm disorders?
A: Atrial fibrillation (a fluttering in the upper chambers of the heart), supraventricular tachycardia (rapid rhythm from the upper chambers of the heart) and ventricular tachycardia (fast rhythm developing from the lower chambers of the heart) are the most common heart rhythm disorders.
Q: What are the symptoms?
A: Most patients with atrial fibrillation and supraventricular tachycardia feel palpitations, skipped beats or "heart jumping out of the chest" sensation. Some patients experience fatigue, lightheadedness, dizziness or a sensation that they are about to pass out. Occasionally, they do pass out because of these arrhythmias; this type of episode is called syncope. Patients with pre-existing heart disease can develop ventricular tachycardia, and some patients may succumb to these malignant arrhythmias.
Q: What treatments are available if I have a heart rhythm disorder?
A: Depending upon the nature and cause of the heart rhythm disorder, various treatment options are available. Supraventricular tachycardia and atrial fibrillation are treated with medications and, in some cases, with radiofrequency ablation. Ventricular tachycardia requires a complex treatment regimen including a combination of medications, radiofrequency ablation and, in some cases, implantation of a defibrillator to shock the heart into a normal rhythm. In patients with pre-existing heart condition, a defibrillator may be implanted to prevent syncope and death secondary to ventricular tachycardias.
Q. What is radiofrequency ablation?
A. Radiofrequency ablation is a widely used procedure for various heart rhythm disturbances. A physician guides a catheter with an electrode at its tip to the various areas of the heart, guided with real-time, moving X-rays displayed on a video screen. Using various techniques, the exact site inside the heart where cells give off the electrical signals that stimulate the abnormal heart rhythm is detected. Then mild, painless radiofrequency energy (similar to microwave heat) is transmitted to destroy this carefully selected group of heart muscle cells in a very small area (about 1/5 of an inch). This procedure stops the rapid heartbeats and hence the palpitations and skipped beats. In a majority of the patients, medications are no longer necessary after successful ablation. This procedure has a success rate of over 90 percent and a low risk of complications. Patients who have this done can resume normal activities in a few days. It causes little or no discomfort and is done under mild sedation with local anesthesia.
Q: Are heart rhythm disorders hereditary? My mother has atrial fibrillation and I’m worried I could have it, too.
A: There is a hereditary component to some rhythm disturbances like atrial fibrillation; however, the majority of patients with heart rhythm disorders do not have family history of heart rhythm disorders.
Q: I get a fluttery feeling sometimes, like my heart “skips” a beat or doesn’t beat normally for a few seconds. If I cough hard, it usually goes away. I passed a stress test. Should I have other tests?
A: Sensation of skipped beats is due to heart rhythm disorder. You would need to be assessed by an electrophysiologist to determine its nature. A stress test will determine if there is adequate blood flow to the heart. However, it is possible to have a rhythm disorder even with adequate blood flow. An electrocardiogram, echocardiogram, event monitor or Holter monitor study will provide better insight into the nature and cause of these skipped beats and guide therapy. In some cases, an electrophysiology study may be necessary for assessment of heart rhythm disorders.
Dr. Jignesh Shah is assistant professor in the UK College of Medicine and a cardiologist specializing in heart rhythm disorders for UK HealthCare.