In This Section      

Electrophysiology and Arrhythmia Service

Johns Hopkins arrhythmia experts
Johns Hopkins arrhythmia experts (left to right) Aravindan Kolandaivelu, Jonathan Chrispin, Charles Love, Hiroshi Ashikaga, Henry Halperin, David Spragg, Hugh Calkins, Ronald Berger, Caridad de la Uz, Joseph Marine, Rotimi Mesubi and Andreas Barth

The Johns Hopkins Arrhythmia Service exists to provide patients with timely and accurate diagnoses and therapies. We do this by using advanced technologies and working as a team with you, your family and your physician to help you continue or return to your normal daily activities as soon as possible. 

History and Goals

The Arrhythmia Service began in the early 1970’s with two goals:

  1. to provide leading edge clinical care for patients with abnormal heart rhythms (arrhythmias)
  2. conduct research to determine the cause of arrhythmias and develop therapies for patients who have arrhythmia associated problems.

As the first such service in Maryland, and one of the first in the United States, the Johns Hopkins Arrhythmia Service rapidly took on a leadership role. An early success was the development and use of the first implantable cardioverterdefibrillator (ICD). In 1980, Dr. Levi Watkins first implanted this device, invented by Drs. Michel Mirowski and Morton Mower, in a patient who had experienced numerous episodes of life-threatening arrhythmias. Since then, ICDs have saved hundreds of thousands of lives and are currently recognized as the most effective treatment to prevent sudden cardiac death.

Doctors on our Arrhythmia Service also focus their efforts on catheter ablation, a minimally invasive technique that can cure a number of arrhythmias. Other areas of major interest include; the causes and treatment of atrial fibrillation, the diagnosis and treatment of inheritable arrhythmias such as arrhythmogenic right ventricular dysplasia, the prevention and treatment of both common and rare problems that may cause sudden cardiac death, device therapy for monitoring and treatment of congestive heart failure, as well as further improving pacemaker and ICD therapy.

Our staff of physicians, nurses, and technologists is available to explain tests and procedures to you and your family, answer your questions, and guide you as you proceed through the diagnostic and treatment process. Some of your questions may be answered by the information we have assembled here for you. But don’t hesitate to ask questions: understanding your care is an important part of a complete recovery.


Electrophysiology is the study of electrical activity in the heart; how the heart beats. Our doctors are cardiologists who specialize in the electrical system of the heart.

Cardiac electrophysiologists (arrhythmia specialists) rely on a patient’s medical history and the results of a variety of procedures to diagnose heart rhythm abnormalities. Once the electrical disorder is diagnosed, the arrhythmia specialist works with your doctor to determine the risk of the heart rhythm abnormality and recommend treatment. Together, you, your primary care doctor or general cardiologist, and the arrhythmia specialist decide on the most appropriate treatment for you.

To be evaluated for an abnormal heart rhythm, one of our physicians will first examine you at the Johns Hopkins Outpatient Center or Johns Hopkins Bayview Medical Center, or at one of our community sites -- Green Spring Station, White Marsh, Odenton, Greater Baltimore Medical Center (GBMC) in Towson, or Columbia. If necessary, you may be asked to undergo one or more of the following tests:

  • An electrocardiogram (called ECG or EKG), records your heart's electrical activity during rest to determining abnormal rhythms
  • A Holter monitor to record your heart's activity during a 24-hour period or longer. Small sensors applied to your skin are connected to a small recording device that is strapped or belted to your body. This is useful for detecting abnormalities that may not occur during an electrocardiogram
  • An event monitor, which records the heart rhythm only when activated and is usually worn for about a month.
  • An exercise stress test also known as treadmill tests, help determine irregular heart rhythms during exercise. During this test, the heart’s electrical activity is monitored through small metal sensors applied to your skin while you exercise on a stationary bicycle or treadmill.
  • A tilt table test may be in order if you experience lightheadedness or fainting. You will be placed on a table that starts in a horizontal position and is then tilted upward at different angles while your heart rate and blood pressure are measured.

Based on your diagnostic exam and test results, our physicians will work with you on a treatment plan which may include:

doctor explaining to adolescent patient

Arrhythmogenic Right Ventricular Dysplasia / Cardiomyopathy (ARVD/C) Program

The Johns Hopkins Arrhythmogenic Right Ventricular Dysplasia (Cardiomyopathy) Program helps patients and their families with screening, education, and advanced medical and surgical treatments.

Learn more about the ARVD/C program