Electrophysiology

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.

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.

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 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.

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

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

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.

This is a 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.

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.

A procedure to remove leads from an implanted cardiac device.