Cardiac Catheter Ablation

Detail of Pulmonary Vein Isolation

In some people, a fast heartbeat, or heart arrhythmia, is triggered by "hot spots" — extra electrical pathways in the heart that are found most commonly in the pulmonary veins, which return blood from the lungs to the heart. In pulmonary vein isolation ablation, patients first undergo electrophysiology testing to locate precisely the extra electrical pathways in the heart.

Before Pulmonary Vein Isolation

Patients come to the clinic several days before the ablation procedure. The patient meets with physicians who specialize in treating heart arrhythmias. Together, the patient and physicians decide the most appropriate treatment option.

If an ablation procedure is necessary, the patient may undergo testing, for example, an echocardiogram, CT scan and lung perfusion scan — even if the tests were previously performed. Patients usually are admitted to the hospital on the morning of the ablation procedure.

During Pulmonary Vein Isolation

The procedure causes little or no discomfort and can usually be done with only conscious (moderate) sedation and a local anesthetic or under general anesthesia.

During the procedure, four to eight catheters (long, narrow tubes) are inserted into different veins and threaded through the blood vessels to different locations in the heart. Some catheters are used to record the heart's electrical activity. In some cases, medications may be given to trigger the heart arrhythmia. Areas of the heart are then mapped to identify abnormal tissue. Sometimes, if the fast heartbeat does not resolve itself, electric shocks may be needed to stop the arrhythmia. Before any shock is administered, patients are given medication for sleep so they don't feel the shock.

Once the hot spots on the heart have been identified, the electrophysiologist uses the catheter tip to apply energy (either radiofrequency to heat, or nitrous oxide to freeze) to the hot spots. The energy ablates (destroys) the hot spots and interrupts the triggers for the heart arrhythmia.

Generally, the procedure takes from four to nine hours. The length of the procedure depends on the number of hot spots and whether other abnormal electrical circuits in the heart need treatment.

Care Following Pulmonary Vein Isolation

After the procedure is completed, patients stay at the hospital for at least 24 hours so that heart rhythm and overall condition can be monitored. Before going home, patients may have a chest X-ray, electrocardiogram (ECG) and an echocardiogram. These tests allow the physicians to view the heart and rule out complications.

If there are no complications or recurrence of heart arrhythmia, patients may leave the hospital. If complications arise, or the arrhythmia returns, the patient will be hospitalized longer. The patient and medical team will discuss instructions regarding medications, activities and follow-up care before the patient leaves the hospital.

Most people resume normal activities a few days.