Northside Hospital Cardiovascular Institute provides heart care that is personal, professional, compassionate and comprehensive. Our team of top board-certified cardiologists are renowned and recognized for ground-breaking research, cardiac expertise, industry leadership and compassionate patient visits.


Located in Braselton, Canton, Crabapple, Cumming, Dahlonega, Dawsonville, Duluth, Gainesville, Lawrenceville, Midtown Atlanta and Sandy Springs-Barfield.

Patient Portal

Patient Forms

Latest News



Understanding Your Heart Rhythm

Heart rhythm disorders are when the heart beat is abnormal including beats that are too fast or too slow. Our highly skilled cardiac electrophysiologists provide expert care for all heart rhythm disorders. We are at the forefront of the latest technologies and techniques to provide the most advanced therapies for managing your heart rate and rhythm. Trust your heart to Northside.

Our Electrophysiology Services

Heart Rhythm Disorders

Abnormal heart rhythms, or arrythmias, occur when there is a problem with the electrical system that is supposed to control a steady heartbeat. With a problem in the electrical system, your heart may beat too fast, too slow, or irregularly.

In any of these situations, your body’s vital organs may not get enough blood to meet their needs.

Learn More

Device Implantation


A pacemaker is a small electronic device that helps regulate a slow heartbeat. The pacemaker is usually implanted in the chest, just below the collarbone. A pacemaker is made of 3 parts. They include a pulse generator, 1 or more leads, and an electrode on each lead. A pacemaker signals the heart to beat when the natural heartbeat is too slow or irregular. Your doctor may recommend this device to keep your heartbeat from slowing down to a dangerously low rate.

Learn More:

Implantable Cardiac Defibrillator (ICD)

An implantable cardioverter defibrillator (ICD) is a small electronic device connected to the heart. It is used to continuously monitor and help control fast and sometimes life-threatening electrical problems with the heart. The ICD responds to life-threatening heart rhythms from the lower chambers of the heart. Pacing corrects a fast rhythm and helps you have a normal heartbeat. A brief shock (defibrillation) resets the heart rhythm if needed to prevent sudden cardiac arrest. An ICD also records and stores information about your heart rhythm and treatments delivered by the ICD for your doctor to review.

Learn More:

Cardiac Resynchronization Therapy (CRT)

Cardiac resynchronization therapy (CRT) is treatment to help restore the normal rhythm (timing pattern) of the heartbeat. CRT therapy means you will need to have the pacemaker placed under your skin by minor surgery. Wires from the device are connected to the ventricles on both sides of your heart. The CRT device sends electrical signals to the ventricles to make them pump together the way they should. This type of electrical stimulation is called biventricular pacing.

Learn More:

Device Lead Extraction

Many people have surgically implanted cardiac devices. These devices can include pacemakers and implantable cardioverter defibrillators (ICDs). Both these devices have 2 main components: a pulse generator and one or more leads. The design of the leads allows them to stay attached to the heart permanently. Sometimes, however, it is necessary to remove leads. This is called lead extraction.

Learn More:

Loop Recorder Implantation

An implantable loop recorder is a heart recording device that looks for causes of fainting, palpitations, very fast or slow heartbeats, and hidden rhythms that can cause strokes. During a loop recorder implantation, your cardiologist does a minor procedure. He or she places the small device under your skin, on your chest wall, overlying the heart. The machine works as an electrocardiogram (ECG). It constantly picks up electrical signal from your heart.

Learn More:

Electrophysiological Study (EP Study)

An EP study is a test used to evaluate your heart’s electrical system and to check for abnormal heart rhythms.

Learn More:

Catheter Ablation

During catheter ablation, a nonsurgical procedure used to treat an abnormal heartbeat, a flexible tube (catheter) is guided into your heart and placed near the small area of heart tissue that may be causing your abnormal heartbeat. Once there, heat (radiofrequency) or cold (cryoablation) energy is used to destroy the tissue.

Learn More:

Supraventricular Tachycardia Ablation (SVT Ablation)

Supraventricular tachycardias (SVT) are a group of abnormally fast heart rhythms (heartbeats). It’s a problem in the electrical system of the heart. The word supraventricular means above the ventricles. With SVT, the abnormal rhythm starts in the upper heart chambers (atria). Also, known as paroxysmal supraventricular tachycardia as these fast heart rhythms may start and stop abruptly and can occur with intervals of normal heart rhythm.

Learn More:

Ventricular Tachycardia Ablation (VT Ablation)

Ventricular tachycardia (VT) is a fast, abnormal heart rate. It starts in your heart’s lower chambers, called the ventricles. VT is defined as 3 or more heartbeats in a row, at a rate of more than 100 beats a minute. If VT lasts for more than a few seconds at a time, it can become life-threatening. Sustained VT is when the arrhythmia lasts for more than 30 seconds, otherwise the VT is called nonsustained. The rapid heartbeat doesn’t give your heart enough time to fill with blood before it contracts again. This can affect blood flow to the rest of your body.

Learn More:

Atrial Fibrillation and Atrial Flutter Ablation

Atrial Fibrillation Ablation

Ablation is a procedure to treat atrial fibrillation. It uses small burns or freezes to cause some scarring on the inside of the heart to help break up and or insulate the electrical signals that cause irregular heartbeats. This can help the heart maintain a normal heart rhythm.

Learn More:  

Atrial Flutter Ablation

Atrial flutter is one of the more common abnormal heart rhythms (arrhythmias). It affects the upper heart chambers (atria). It’s caused by an abnormal electrical circuit that makes the atria beat quickly and flutter instead of fully squeezing. It can result in fast heart rates and a heart that doesn’t work as well as it should. This causes symptoms and increases the risk for stroke.

Learn More:  

Atrial Fibrillation Stroke Prevention

Blood thinner, LAAC/WATCHMAN

Atrial fibrillation (AFib) increases the risk for stroke, so stroke prevention is an important part of treatment. This means taking medicines commonly referred to as “blood thinners” or an alternative, such as a procedure to place a device in the heart.

Learn More:

Cardiac Rhythm Monitoring

An event monitor is a portable device used to record your heart’s electrical activity when you have symptoms. It records the same information as an electrocardiogram (ECG), but for a longer time. Most of these devices can sent the recorded information directly to your healthcare provider. This lets him or her analyze the electrical activity of your heart while you are having symptoms or shortly thereafter.

Learn More:

Heart Rhythm Research Studies


Find a Northside Hospital Cardiovascular Institute device and electrophysiology clinic near you.

Electrophysiology Clinic Locations


Device Clinic Locations



Find a Northside Hospital Cardiovascular Institute cardiologist that specializes in electrophysiology.

Alok Gambhir, MD, PhD, FACC, FHRS
Chief of Cardiac Electrophysiology, Northside Health System
Niraj Sharma, MD, FACC, FHRS