Electrophysiology is a specialty within the field of cardiology that diagnoses and treats problems related to the electrical system of the heart, called cardiac arrhythmias. At Lahey Hospital & Medical Center, our cardiac electrophysiologists use a variety of tests to evaluate symptoms that may be related to cardiac arrhythmias.

Common symptoms of arrhythmias include palpitations, irregular or racing heartbeat, shortness of breath, fatigue at rest or with exertion and fainting.

There are a variety of wearable heart monitors that can be of use in evaluating a patient’s heart rhythm during normal activities. These range from a 24-hour Holter monitor to 30-day monitors for symptoms that are infrequent, to small (size of a wooden matchstick) implantable monitors that can be worn for up to 3 years (see picture below). Our doctors also use electrophysiology studies to test the electrical activity of the heart.

During an electrophysiology study, the physician inserts a thin catheter into a blood vessel in the groin that leads to the heart. Electrodes on the tip of the catheter allow the physician to study the electrical system of the heart.

Electrophysiology studies can determine where an abnormal heartbeat is coming from. The results help guide appropriate treatment such as medication, an implantable pacemaker or defibrillator, a procedure called cardiac ablation, or surgery, all of which are available through Lahey

Advanced Electrophysiology Procedures at Lahey

Atrial Fibrillation Ablation: Atrial fibrillation is the most common cardiac arrhythmia, affecting approximately 5 million people in the Unites States. When medication is ineffective in controlling the arrhythmia, catheter ablation may be offered.

There has been a tremendous amount of research and technology devoted to catheter ablation for atrial fibrillation over the past 20 years. Today, the results of catheter ablation for atrial fibrillation are better than ever, with shorter procedure times, reduced hospitalization stays, reduced complications and better results in preventing recurrences. As a result of improvements in many aspects of the procedure, 90% of patients are able to be discharged the same day. There are several different types of catheter ablation procedures for atrial fibrillation. Be sure to discuss with your doctor which procedure is best for you and your arrhythmia.

  • Cryoballoon Ablation: This procedure uses a balloon that is filled with a gas to freeze specific areas of the heart known as pulmonary veins. These areas are known to cause atrial fibrillation in the majority of patients. The cryoballoon ablation procedure is particularly effective for patients with an early form of atrial fibrillation called paroxysmal.
  • Radiofrequency Ablation: This form of ablation uses radiofrequency energy to heat the tip of the catheter and burn selective areas. This type of ablation offers the flexibility to deliver energy to any area of the heart that may be causing atrial fibrillation.
  • Convergent Procedure: The Convergent Procedure is a minimally invasive ablation procedure that combines the best techniques of an electrophysiologist and a cardiac surgeon to restore the heart’s rhythm. The combined procedure gives patients with the most advanced form of atrial fibrillation the best chances of restoring and maintaining normal heart rhythm.

Supraventricular Tachycardia: This type of arrhythmia arises from the top chambers of the heart and is a frequent cause of a racing heart beat or palpitations. Catheter ablation has very high success rates for eliminating this arrhythmia and is generally an outpatient procedure with extremely high rates of complete cure.

Premature Ventricular Contraction (PVC) Ablation: PVCs are a frequent cause of “skipped beat.” Actually, the PVC is an extra beat that often generates a lower amplitude pulse that can be hard to detect. It often feels like the heart is missing a beat. Patients often feel the more forceful beat following the PVC. When medication is ineffective or not tolerated catheter ablation is very successful in eliminating PVC’s.

Ventricular Tachycardia Ablation: Ventricular tachycardia is an abnormal rapid heart rhythm arising from one of the bottom chambers of the heart. Typically this occurs in patients with a previous heart attack which has damaged the electrical system. In other patients the heart may be normal with the exception of a small cluster of cells generating abnormal signals resulting in ventricular tachycardia. In patients with recurrent ventricular tachycardia there are many treatments available, including an implantable defibrillator, medication and ablation.

Left Atrial Appendage Occlusion Procedures: It is estimated that 5 million people are affected by atrial fibrillation (AF) in the U.S. and it is expected that number will more than double by the year 2050. Patients with atrial fibrillation have a five-fold higher risk of stroke compared to those without.

In patients with nonvalvular (not related to rheumatic mitral stenosis) atrial fibrillation, studies have shown that 90% of stroke-causing clots are located within a part of the heart called the left atrial appendage. While blood thinners have been shown to reduce the stroke risk, only about 60% of patients indicated for blood thinners are prescribed these drugs. In patients who are given a prescription for blood thinners, about 25% of patients will have stopped taking the drugs by 2 years. For these reasons, a newer approach to stroke risk reduction in patients with nonvalvular atrial fibrillation was developed.

  • Watchman Procedure: Watchman Procedure: The Watchman is a left atrial appendage occlusion device which is inserted through a vein in the groin (Figure 1). The procedure takes approximately 60 minutes and the majority of patients are discharged home after a single night in the hospital the same day. Over the course of the last 150 years more than 22000 patients were studied in the Watchman trials in randomized comparison to warfarin for stroke prevention in patients with nonvalvular atrial fibrillation. The results have shown equivalence to warfarin with respect to stroke reduction with a significant reduction in major bleeding.The FDA approved the Watchman device in March 2015 as an alternative to warfarin in patients with nonvalvular atrial fibrillation. Beginning in 2011, Lahey Hospital and Medical Center began participating in the first of 2 clinical trials of the Watchman device. Following FDA approval of the Watchman in 2015, Lahey became the first center in Massachusetts to implant patients with the device. Candidate patients for the Watchman LAA occlusion device generally:
  1. Have nonvalvular atrial fibrillation with an elevated stroke risk
  2. Are not suitable for long-term blood thinners

Pacemaker and Implantable Cardioverter Defibrillator (ICD) Implantation: For patients in whom the heart beat is too slow symptoms of fatigue, shortness of breath or fainting may occur. A pacemaker is a small device inserted under the skin of the upper chest. The pacemaker is connected to wires threaded through a vein under the collarbone that are positioned in the heart. In other patients with more serious arrhythmias coming from the bottom chambers of the heart (ventricular tachycardia) an implantable defibrillator may be implanted. This device can monitor the heart’s rhythm and deliver a life-saving electrical shock automatically when needed.

Leadless Pacemaker: This is a very recent development in pacemaker technology in which the pacemaker is completely implanted in the heart, with no wires in the blood vessels and no battery or generator in the chest. It is inserted through a vein in the groin and has most of the features of a traditional pacemaker.

Cardiac Resynchronization Therapy (CRT): In many patients with weakening of the heart muscle congestive heart failure may develop, leading to symptoms of shortness of breath, fatigue and exetional intolerance. In many patients, medications are very effective in controlling and improving symptoms. In some patients electrical abnormalities of the electrical system (left bundle branch block) may contribute to the weakening of the heart muscle. CRT uses a traditional pacemaker or defibrillator with an extra wire placed onto the left ventricle to help improve the electrical and mechanical pump function of the heart.

Laser Lead Extraction

Arrhythmia Device Clinic

The Arrhythmia Device Clinic at Lahey Hospital & Medical Center, sometimes referred to as the Pacemaker Clinic, is a specialized outpatient clinic where patients who have implanted cardiac devices are routinely followed. Over the years, implanted cardiac devices have grown in their sophistication from the simple pacemaker of years ago, to include pacemakers and defibrillators, that monitor and intervene on cardiac rhythm, as well as newer devices used mainly for the detection of cardiac arrhythmia.

Patients first visit the clinic usually one month after having such a device implanted. Thereafter, in person visits may be once or twice yearly. In addition, the great majority of these devices are followed from home as well, known as remote monitoring, using the patient’s phone or internet access. Some of the older pacemakers are followed every few months over the phone.

The Arrhythmia Device Clinic provides a strong connection between patients with pacemakers or defibrillators and Lahey Hospital & Medical Center. Technical information is taken from the devices either in person, or monitoring from home, as well as clinical information from the patients, and relayed to their physicians, usually their cardiologists. A close relationship often forms between our device patients and our staff of nurses and cardiovascular technicians, and we are an indispensable link between patient and specialist. Furthermore, the clinic acts as an ongoing source of support and education for patient regarding their devices and heart rhythm.

We currently follow over 4000 patients with devices, with over 3000 in person visits and well over 11,000 home checks performed annually. Lahey Hospital & Medical Center has been at the forefront of cardiac rhythm device implantation and management for years endowing us with experience and resources to follow patients with such devices efficiently and expertly.

The Arrhythmia Device Clinic at Lahey Hospital & Medical Center is led by Dr. Florence M. Parrella, a senior staff electrophysiologist and expert in arrhythmia device optimization along with a team of nurse specialists and pacemaker technologists.

For further information about the Arrhythmia Device Clinic, please call Sarah Leclerc at 781-744-8863 by following the prompts for the Pacemaker Clinic.


Clinical Cardiac Electrophysiology Fellowship

The Arrhythmia Section within the Division of Cardiovascular Medicine offers a two-year fellowship in Clinical Cardiac Electrophysiology (CCEP) designed to provide comprehensive subspecialty training for individuals planning to pursue a career in this field. Lahey Hospital and Medical Center has a complement of 4 ACGME-accredited positions in which 2 fellows are selected through the National Residency Matching Program each year. Click here for more information

All fellows will have completed the required three-year training in Internal Medicine and fellowship in Cardiovascular Diseases at ACGME-accredited or equivalent training programs. Fellows are expected to be able to function at a level commensurate with such experience.

The Lahey program is predominantly clinical in its focus, with a wealth of clinical material from which to derive practical educational experiences. Fellows should expect to participate in 800-1,000 procedures over the course of two years, far exceeding the COCATS requirements for CCEP training. After the satisfactory completion of this fellowship, the graduate will be capable of serving as an independent consultant and specialist in clinical cardiac electrophysiology.

The collaborative relationship between attending physician and trainees in the delivery of patient care is at the core of this Program; the provision of high-quality patient care is the fundamental vehicle for teaching and learning of all the required competencies. Clinical training is augmented with daily intracardiac electrogram reviews, weekly conferences used for journal club, case studies, didactic lectures and research meetings. Fellows are encouraged to participate in scholarly activities including publication of case reports, independent research and projects focused on quality improvement and patient safety. Each fellow also participates in a longitudinal ambulatory clinic with a weekly, supervised half-day session in which they learn and master outpatient arrhythmia management.

Our faculty consists of six board certified electrophysiologists, each with a faculty appointment at Tufts University School of Medicine. We also have a highly skilled team of advanced practitioners who work in both inpatient and outpatient settings.

Fellows will participate in three primary clinical rotations:

  1. Invasive EP lab: 2 out of every 4 weeks
  2. Inpatient consult service: 1 out of every 4 weeks
  3. Float week: 1 out of every 4 weeks
  4. Ambulatory clinic: One half day per week

Lahey Hospital & Medical Center is the primary site for all rotations however, senior EP fellows will also have the opportunity to rotate through Beverly Hospital for both clinic and lab experiences in a community hospital setting.

Interested fellows should apply through the Electronic Residency Application Service (ERAS) and will be selected for fellowship through the National Residency Matching Program (NRMP).  Please visit of the ERA and NRMP websites for important dates and timelines.

To learn more about the Lahey CCEP program and faculty, click here.

Jonathan S. Silver, MD, FACC, FHRS

CCEP Fellowship Program Director

Program Contact
 Donna Rizzo
CCEP Fellowship Coordinator
[email protected]

Meet The Electrophysiology Team

Lahey offers a highly regarded Electrophysiology fellowship. Learn more.