Atrial Fibrillation and other Arrhythmias
Types | Causes | Diagnosis | Treatment
An arrhythmia is an abnormal heart rhythm. There are several types of arrhythmias, named by the chambers of the heart in which they occur (atria or ventricles) and by what effect they have on the heart's rhythm. An arrhythmia may happen for different reasons:
- The heartbeat may begin in a part of the heart other than the sinus node
- The sinus node may develop an abnormal rate or rhythm
- A heart block (delay in the normal flow of electrical impulses that cause the heart to beat) may be present.
Any of these may cause the heart to skip a beat, beat too fast, or beat too slow. Atrial fibrillation (AF) is a form of arrhythmia, or irregular heartbeat, in which the atria (the two small upper chambers of the heart) quiver instead of beating effectively.
Types of Arrhythmia
The two major types of heart arrhythmia are tachycardia (fast arrhythmia) and bradycardia (slow arrhythmia).
Tachycardia is defined by a heart rate over 100 beats per minute. There are three major types of tachycardia:
- Atrial tachycardia (starting in the atria)
- Supraventricular tachycardia (starting above the ventricles)
- Ventricular tachycardia (starting in the ventricles)
Bradycardia refers to a slow heart rhythm, caused by a failure of the heart signals to fire as they should.
Atrial fibrillation (AF) is a form of arrhythmia, or irregular heartbeat, in which the atria (the two small upper chambers of the heart) quiver instead of beating effectively. It is one of the most common forms of cardiac arrhythmia, affecting 0.4% of the general population and 5 to 10% of persons over 65 years of age. In addition, AF occurs in as many as 50% of patients undergoing cardiac operations.
Abnormalities in the heart's electrical impulses in patients with AF cause blood to be pumped improperly, resulting in pooling or clotting. If a blood clot moves to an artery in the brain, AF can lead to stroke. AF is also associated with increased risk of congestive heart failure and cardiomyopathy (heart muscle disease). These risks warrant medical attention for patients with AF even if symptoms are mild. While nonsurgical treatment options, such as electrical cardioversion, often help restore a normal rhythm initially, recurrence rates as high as 75% have been reported.
Columbia's surgical atrial fibrillation program is led by Michael Argenziano, MD, Director of Arrhythmia Surgery, and the management team are trained in the most innovative treatment options for atrial fibrillation. The Columbia team has performed surgical atrial fibrillation ablation (SAFA) in more than 600 patients, with a success rate (normal rhythm) at 6-12 months of 76%. The majority of these operations have been performed in conjunction with other cardiac procedures (such as valve repair or coronary bypass), but the procedure can also been used for atrial fibrillation as the sole indication.
Causes of Arrhythmia
It is not always clear what causes an arrhythmia. Possible causes include heart disease, aging, myocardial ischemia (reduced blood flow to heart muscle), electrical conduction disorders, stress, caffeine, tobacco, alcohol, diet pills, and cough medication. In the case of tachycardia, complicating factors include heart attack, heart valve disease, angina, and emphysema.
Diagnosis of Arrhythmias/ Atrial Fibrillation
Arrhythmias are diagnosed through medical history, physical examination, and EKG. Upon diagnosis, tachycardia is treated with medical therapies including anticoagulants to prevent blood clots and stroke, anti-arrhythmic to control rate and rhythm of the heart or beta-blockers to help lower blood pressure or other surgical options. For select patients, surgical treatments such as radiofrequency ablation or ICD implantation may be recommended. Bradycardia is most often treated with a pacemaker to keep the heart beating at a regular pace.
Treatment of Arrhythmias/ Atrial Fibrillation
Atrial fibrillation (AF) is a form of arrhythmia, or irregular heartbeat. In patients with AF, the two upper chambers of the heart (the atria) quiver instead of beating effectively. The Surgical Atrial Fibrillation Program at NYP/Columbia, one of the most experienced in the nation, offers a variety of solutions for this condition, and our expert surgeons have performed over 1000 procedures for AF.
The Maze Procedure and Surgical Atrial Fibrillation Ablation (SAFA)
These operations treat AF by interrupting the electrical impulses that cause the abnormal heart rhythm. These interruptions are caused in a variety of ways, including incisions in the atrial walls, heating of the heart tissue with radiofrequency probes, or freezing with cryothermy probes. Columbia surgeons have developed several atrial fibrillation ablation procedures, including minimally invasive and off-pump versions, totally closed-chest (robotic) ablation, and hybrid ablations, in which the procedure is made less invasive by combining surgical and catheter-based ablation techniques. The specific approach used is determined by each patient’s unique characteristics and anatomy, and these ablations can be performed for patients with “lone AF” or those having another cardiac operation, such as coronary bypass or valve surgery.
The MAZE Procedure
The MAZE Procedure is a surgical approach that treats atrial fibrillation by interrupting the electrical impulses that cause abnormal heart rhythm. The surgery typically involves the placement of incisions in both atria, however can be modified to suit a given patient's condition. When the incisions heal, scar tissue forms and prevents abnormal electrical impulses from passing through the heart. This technique is highly effective in curing atrial fibrillation. However, potential complications of the procedure include fluid retention and other risks associated with open heart surgery such as bleeding, infection, stroke, and pneumonia. For these reasons, and because the classical MAZE procedure requires a breastbone splitting incision, use of the heart-lung machine, and multiple incisions in the heart, this procedure has not been embraced by many patients and physicians.
Surgical Atrial Fibrillation Ablation (SAFA)
To reduce the risks and trauma associated with the classic MAZE operation, surgeons at Columbia University Medical Center Heart Institute have developed modification of the MAZE, known as Surgical Atrial Fibrillation Ablation (SAFA). In these procedures, a variety of energy sources such as radiofrequency, microwave, or laser, are used to create a limited number of scars in the left atrium, avoiding the need for many incisions in the heart. Furthermore, our surgeons have developed minimally invasive versions of SAFA, in which left atrial lesions can be made without opening the breastbone or using the heartlung machine.
Totally Endoscopic Beating Heart Atrial Fibrillation Ablation
The Columbia team has developed a totally endoscopic, beating heart version of surgical atrial fibrillation ablation. In this minimally invasive, robotic operation, the ablation is performed through small puncture wounds in the chest and without stopping the heart or using the heart-lung machine. We performed our first such closed chest, off-pump atrial fibrillation operation in February 2003, and we now offer this approach as a clinical option for treatment of lone atrial fibrillation.
Electrophysiology Studies (EPS)
Electrophysiology Studies (EPS) are used to assess changes in the heart rhythm that are not controlled with medications. Learn about electrophysiology testing here.
Electrophysiologists may also implant pacemakers and defibrillators to prevent or to treat symptoms. Learn about Pacemakers & Defibrillators for Cardiac Arrhythmias here.
If you have heart disease and need help, we’re here for you. To get started today, call (212) 305-2633 or use our appointment request form.