Electrophysiology

In a normal and healthy heart, the four chambers contract (squeeze) in a very organized way. This helps the heart pump all the blood the body needs. In atrial fibrillation, the electrical impulse of the heart is not regular. The upper chambers of the heart beat irregularly and rapidly – at 300 beats per minute – and out of coordination with the two lower chambers of the heart. As a result, the heart may not pump enough blood to meet the body's needs. This causes poor blood flow, resulting in symptoms such as fatigue and shortness of breath. Up to 5 million people in the United States suffer from atrial fibrillation, making it one of the most common heart rhythm disturbances. It can affect both men and women and becomes more common as you get older.

The electrophysiologists at the CHI Health Clinic Heart Institute specialize in treating atrial fibrillation with the latest technology, procedures and devices. They work collaboratively with our general cardiologists and interventional cardiologists as well as cardiovascular surgeons to provide high-quality patient centered care.

Afib Symptoms

• Rapid or irregular heart rate
• A sense that your heart is pounding, skipping or fluttering.
• Feeling tired or unable to complete normal daily activities
• Chest pain or tightness
• Shortness of breath
• Dizziness or feeling lightheaded
• Fainting
• Increased need to go to the bathroom
• Swelling in the legs

Tests for Afib

• EcG
• Event monitor
• Holter monitor (24-hour test)
• Implanted loop recorder
• Echocardiogram (ultrasound imaging of the heart)

Atrial Fibrillation Treatment Options

Medicine

Daily medicines taken by mouth may also be used to slow the irregular heartbeat. These medications may include beta-blockers, calcium channel blockers, and digoxin. Medicines may also be used to keep atrial fibrillation from coming back. These medications may work well in many people, but they can have serious side effects. Many patients go back to atrial fibrillation, even while taking these medications.

Blood thinners — such as heparin, warfarin (Coumadin), apixaban, and dabigatran (Pradaxa) — reduce the risk of a blood clot traveling in the body (such as a stroke). Because these drugs increase the chance of bleeding, not everyone can use them. Antiplatelet drugs such as aspirin or clopidogrel may also be prescribed. Your doctor will consider your age and other medical problems when deciding which drug is best.

Procedures

To help get the heart back into normal rhythm right away, electrical cardioversion may be used. This may involve electrical shocks or special drugs given through the veins. They may be done as an emergency, or planned ahead of time.

A procedure called ablation can be used to treat areas in your heart that may be causing your heart rhythm problems. Radiofrequency or Cryoablation Techniques (freezing) are available.

What is Device (Pacemaker and Defibrillator) Interrogation?

Your pacemaker or defibrillator has the ability to communicate through the skin with a programmer we have in the office. We perform this interrogation by placing a wand over your chest where the device is located.

What are the indications for the procedure?

We routinely evaluate the programming of your device and confirm that the battery and wires (leads) are functioning appropriately. Device interrogation can be done routinely in the office setting or remotely.

How is it done?

We place a wand over your device that is linked to a special computer called a programmer. When the programmer and the device communicate, valuable information can be obtained from the memory of your device and we can change the programmed settings if needed.

Typically we start by evaluating the remaining lifespan of the battery and we can usually give you some idea about how long the battery will last. We test the function of the leads and make sure they conduct electricity both to and from your heart. We can also modify the programmed parameters to better suit your heart’s individual needs. If you have any questions or concerns about your pacemaker or defibrillator please bring them up and we can address them.

How do you prepare for the procedure?

No preparation is needed. In the office, our staff will have the necessary equipment to check your pacemaker or defibrillator. At home, you will also have special equipment to transmit tracings over the phone.

What are the risks of the procedure?

There are little or no risks of the procedure. With testing occasionally you can feel some mild lightheadedness with the interrogation and testing of you device.

What Is Electrical cardioversion?

Electrical cardioversion (CV) is a procedure where a patient with a rhythm abnormality undergoes sedation and receives an electrical shock to the chest meant to convert the heart back to normal rhythm. In certain individuals CV is accompanied by a transesophageal echocardiogram (TEE) for visual assessment of the heart prior to the procedure.

How is it done?

You will start by discussing the nature of the procedure with your cardiologist along with the risks and alternatives. On the day of the CV you'll come to the hospital where baseline blood testing will be done to verify that your electrolytes and blood counts are stable. You'll be prepped for conscious sedation and have electrical pads placed on your chest and back. You will then be briefly sedated and your cardiologist will deliver a shock to your chest. With adequate sedation the procedure is painless. This very quick series of events takes no more than a few minutes. Your doctor will know immediately if the CV has been successful and will arrange for an electrocardiogram to confirm the presence of a normal rhythm. If the CV is not successful with one shock your doctor may deliver one or more successive shocks in short order. As noted above, some patients will need to undergo TEE along with the CV, but both procedures will be done during the brief time you are sedated. 

What are the indications for the procedure?

Elective CV is most commonly recommended for the atrial rhythm abnormalities atrial fibrillation (AF) and atrial flutter. If you suffer from persistence of either rhythm and have associated symptoms (such as shortness of breath, lightheadedness, fatigue, palpitations, or exertional intolerance) you may benefit from CV as a means of returning your heart to normal rhythm. We sometimes recommend CV as an isolated therapy or in conjunction with the use of medications meant to stabilize cardiac rhythm.

How do you prepare for the procedure?

Your doctor will give you detailed instructions, but in general all you need to do is arrive at the hospital fasting for at least 12 hours. You will likely be instructed to take all your usual medications on the morning of the CV. Male patients should expect to have their chest and/or back shaved as part of the preparation (in order to improve electrical contact between the pads and the skin).

What are the risks of the procedure?

Despite the seemingly dramatic outward appearance of CV it is actually one of the least risky procedures that cardiologists perform. The greatest risk you'll face has to do with the conscious sedation, but risk is no different from that seen with typical sedation for other procedures. The shock itself can theoretically trigger a more dangerous rhythm abnormality but this is exceedingly uncommon and easily treated. Because stroke can rarely accompany conversion of AF to normal rhythm you'll either need to be on the blood thinner warfarin (Coumadin) or undergo TEE to exclude the presence of clot in the left atrium of the heart. The most common adverse outcome of CV is that it simply doesn't work. Your doctor should be able to give you some idea prior to the procedure what chance of success you might have and what options exist if your heart continues in AF despite CV.

Holtor Monitoring

What is a Holter monitor?

A Holter monitor is a small heart monitor that is worn for at least 24 hours and continuously records your heart rhythm.

What are the indications?

A Holter monitor is used to help diagnose heart arrhythmias and evaluate the cause of palpitations, lightheadedness and fainting. In patients known to have certain rhythm abnormalities such as atrial fibrillation we will use a Holter monitor to assess how well our medication is controlling the heart rate.

How is it done?

You are usually hooked up to the Holter monitor before you leave the office, Emergency Care department or hospital. We will clean your chest with alcohol and apply a special adhesive to make the electrode patches stick. If you are a male patient, we may have to shave 2-3 areas on your chest to ensure that the patches will remain intact. Three to five electrodes or EKG patches will be stuck to your chest and the monitor leads will be attached to them. The monitor may be worn in a pouch around your neck or it can clip to your belt.

You will be given a diary to record your activity or any symptoms you experience during the monitoring period. It is very important that you fill this out and bring it back to our office when you return the Holter monitor. This will allow the physician to correlate your symptoms with the monitor readings provided and help make an accurate diagnosis.

How do you prepare for it?

It is important to shower before the Holter monitor is attached to your chest. You will not be able to remove the electrodes for 24 hours while wearing the monitor. This allows us to receive the most accurate information regarding your heart rhythm.

Our staff will show you how to replace an electrode or patch if it becomes loose or falls off. Please alert our staff if you are allergic to adhesives—we can provide nonallergic patches to wear during your test.

What are the risks?

There is no meaningful risk associated with this test. As noted above, some persons exhibit skin sensitivity to the adhesive on the EKG patches.

Event Monitoring

Event monitors are used to record heart rate and rhythms for brief periods. They help doctors diagnose problems that don’t happen often enough for an EKG or Holter monitor to record. The monitor may be worn up to 30 days.

Event monitors work only when a person turns on the device. When you experience symptoms, you activate the device and make a recording of your heart’s electrical activity. Because there are different models of event monitors, they can be worn like a wristwatch, carried in your purse or pocket, or worn like a beeper.

Implantable Loop Recorder (ILR)

The implantable loop recorder (ILR) is a subcutaneous, single-lead, electrocardiographic (ECG) monitoring device used for diagnosis in patients with recurrent unexplained episodes of palpitations or syncope. The device is typically implanted in the left parasternal region and is capable of storing ECG data automatically in response to preset parameters (including significant bradyarrhythmias, tachyarrhythmias, or pauses) or patient activation. It is particularly useful either when symptoms are infrequent or when the burden of certain arrhythmias needs to be assessed. It is a very simple outpatient procedure which only takes minutes, but could provide long-term data up to three years.

What is an ICD?

An ICD is a device, about the size of a deck of cards, which is implanted under the skin and has wires (leads) that pass into the heart. The main purpose of the ICD is to monitor the heart for the life-threatening rhythms ventricular tachycardia (VT) and ventricular fibrillation (VF) that can lead to cardiac arrest and death. The ICD can terminate the abnormal rhythm and restore normal rhythm by delivering a powerful shock to the heart muscle or through a special type of cardiac pacing.

The ICD also has all the functions of a pacemaker and can send very small electrical impulses to the heart to stimulate contraction of the heart. This function keeps the heart from going to slow in patients where this is a problem.

What are the indications for the procedure?

Sudden cardiac arrest from VF and VT is a common cause of death among patients whose heart muscle is weak. When the ejection fraction (defined below*) is below 35% the risk of lethal arrhythmia rises. Most patients with a heart that has been weakened by causes not considered immediately reversible (such as prior heart attacks and viral illnesses) are at higher risk of VT and VF and should be considered candidates to receive an ICD.

How is it done?

When we’re ready to start you’ll be brought into the cardiac catheterization lab (much like an operating room with x-ray cameras) and you’ll lie on a table while our technicians prepare the area on your body where we’ll be working. In most patients we place the ICD just below the collarbone on the left chest wall. We can also implant the ICD on the right if there is a reason the left side can’t be used (e.g. a patient with a left arm dialysis fistula or previous surgery for breast cancer). The technicians will cover your chest and face with a drape to protect the sterile area where we’ll work (the drape over the face can bother some patients—we can provide more sedation to you if you think this will be a problem). After providing you with some sedating medication we numb the area of skin with local anesthetic.

We make an incision about two inches long and then create an area under the skin where we can place the ICD. We pass the wires (leads) into veins that lead directly into the right atrium and ventricle of the heart. Once we place and secure the leads in the heart we test them electrically to make sure we have good conduction and adequate position to pace the heart. We attach the leads to the ICD and place it under the skin. At that point you will be fully sedated and we will test the shock function of the ICD. Finally, we close the skin with absorbable suture so that you will not need stitches removed. You will stay in the hospital overnight so that we can observe your heart rhythm and check the status of your ICD and leads in the morning. There is a small chance that one of the leads will pull free from where we put it within the first few hours after surgery. We are able to easily detect this on the morning after surgery and return to the cath lab to fix it if necessary.

If all goes well you are discharged from the hospital on the day after surgery.

How do you prepare for the procedure?

ICD insertion is done on both hospitalized and ambulatory patients. As an outpatient having this done electively you will first visit with the cardiologist in the office to go over the procedure and discuss the risks and alternatives. Since you will be asked to sign document of consent be sure to ask any question and raise any concern you may have. You will need to have basic blood work done and this can be drawn in the office.

Unless instructed otherwise you should be fasting on the morning of the procedure. In general we want you to take your usual morning medications with the exception of any we’ve told you not to take (please talk to our nurses or schedulers if you have any questions about this).

We do this procedure in the hospital at CUMC - Bergan Mercy, Midlands, Mercy, Immanuel and Lakeside. You’ll receive specific instructions on where to show up and what time to be there.

What are the risks of the procedure?

The risk of bleeding and bruising accompanies any invasive procedure. The risk of infection of the ICD site is about 1-4% nationally. Because the vein we use to gain access to the heart lies very near the lung there is the possibility of puncturing and collapsing the lung, necessitating the placement of a chest tube. There is a small risk of leads perforating the muscle in the heart and causing potentially life-threatening bleeding around the heart.

These complications are uncommon and we can take measures to treat them when they arise. We take all these potential complications very seriously and take great precautions to avoid them.

* Ejection Fraction: We quantify the strength of the left ventricle (the main pumping chamber) by referring to the heart’s ejection fraction, a measure of the percentage of blood squeezed out of the heart with each beat. The left ventricle doesn’t wring every drop out with each beat, but rather pushes out about two thirds of its full volume. This number is the ejection fraction. The normal ejection fraction is between 55 and 75%.

What is a pacemaker?

A pacemaker is a device, about the size of 4 stacked silver dollars, which is implanted under the skin and has wires (leads) that pass into the heart. It sends a very small electrical impulse through the leads into the muscle of the heart about once every second to stimulate contraction of the heart. Its main purpose is to make sure a person’s heart rate does not become too slow.

What are the indications for the procedure?

A pacemaker is useful for anyone who has symptoms due to a slow heart rate. At very low heart rates (in the 20s and 30s) a person can develop lightheadedness, fainting, shortness of breath and congestive heart failure. With rates in the 40s and 50s a person can still feel lightheaded and weak. A pacemaker in people with slow heart rates can dramatically improve symptoms.

Sometimes people have a normal heart rate that occasionally drops very low or they have short periods (several seconds) where the heart stops beating. This can result in sudden loss of consciousness with the danger of falling and injury. A pacemaker in this situation will prevent these episodes from occurring.

Atrial fibrillation is a common rhythm problem that results in rapid heart rates. If the atrial fibrillation is intermittent, the intervening periods of normal heart rhythm can be uncomfortably slow especially if we use medications that slow the heart rate down. A pacemaker in this situation provides protection against slow heart rates so that we can increase the doses of drugs that keep the atrial fibrillation from racing too fast.

How is it done?

When we’re ready to start you’ll be brought into the cardiac catheterization lab (much like an operating room with x-ray cameras) and you’ll lie on a table while our technicians prepare the area on your body where we’ll be working. In most patients we place the pacemaker just below the collarbone on the left chest wall. We can also implant the pacemaker on the right if there is a reason the left side can’t be used (e.g. a patient with a left arm dialysis fistula or previous surgery for breast cancer). The technicians will cover your chest and face with a drape to protect the sterile area where we’ll work (the drape over the face can bother some patients—we can provide more sedation to you if you think this will be a problem). After providing you with some sedating medication we numb the area of skin with local anesthetic. We make an incision about an inch and a half long and then create an area under the skin where we can place the pacemaker. We pass the wires (leads) into a vein which leads directly into the right atrium and ventricle of the heart. Once we place and secure the leads in the heart we test them electrically to make sure we have good conduction and adequate position to pace the heart. We attach the leads to the pacemaker and place it under the skin. We close the skin with absorbable suture so that you will not need stitches removed. You will stay in the hospital overnight so that we can observe your heart rhythm and check the status of your pacemaker and leads in the morning. There is a small chance that one of the leads will pull free from where we put it within the first few hours after surgery. We are able to easily detect this on the morning after surgery and return to the cath lab to fix it if necessary.

If all goes well you are discharged from the hospital on the day after surgery.

How do you prepare for the procedure?

Pacemaker insertion is done on both hospitalized and ambulatory patients. As an outpatient having this done electively you will first visit with the cardiologist in the office to go over the procedure and discuss the risks and alternatives. Since you will be asked to sign document of consent be sure to ask any question and raise any concern you may have. You will need to have basic blood work done and this can be drawn in the office.

Unless instructed otherwise you should be fasting on the morning of the procedure. In general we want you to take your usual morning medications with the exception of any we’ve told you not to take (please talk to our nurses or schedulers if you have any questions about this).

We do this procedure in the hospital at CUMC - Bergan Mercy, Midlands, Mercy Council Bluffs, Immanuel and Lakeside. You’ll receive specific instructions on where to show up and what time to be there.

What are the risks of the procedure?

The risk of bleeding and bruising accompanies any invasive procedure. The risk of infection of the pacemaker site is about 1-4% nationally. Because the vein we use to gain access to the heart lies very near the lung there is the possibility of puncturing and collapsing the lung, necessitating the placement of a chest tube. There is a small risk of leads perforating the muscle in the heart and causing potentially life-threatening bleeding around the heart.

These complications are uncommon and we can take measures to treat them when they arise. We take all these potential complications very seriously and take great precautions to avoid them.