Arrhythmia Associates LLP

Our Process - Diagnosis - Non-Invasive Testing

Non-Invasive Testing

Click on any testing process below to learn more:

The Electrocardiogram (ECG or EKG)

is a simple test performed by recording the amplified electrical activity of the heart from the body's surface. Careful analysis of the ECG during arrhythmia can establish the nature of the rhythm disturbance. An ECG recording at the time of the arrhythmia is the foremost way of establishing the diagnosis. This not only verifies that an arrhythmia is present, but it gives information about exactly what type of arrhythmia it is. This leads to the therapy or therapies uniquely best suited for that arrhythmia

Holter monitoring is a continuous recording of an ECG for 24 or 48 hours. Electrodes on the skin's surface record the heart's electrical activity, and the signals are saved and later analyzed. A holter monitor can be placed by your cardiologist or by our practice.

The event recorder is a kind of Holter that is a continuous loop recording device. It can be "worn" for a whole month and the patient alerts the device when an arrhythmia symptom appears by pushing a button. The saved signals can be transmitted over a telephone to the doctor's office for analysis.

The exercise test (on a treadmill) is especially useful for arrhythmias experienced only during exercise. The patient wears several electrodes attached to an ECG machine and walks progressively faster on the treadmill. This is also a way of evaluating whether or not coronary artery blockages are present.

Preparation
Do not eat or drink anything after midnight the evening before your procedure. If you must take medications, drink only small sips of water to help you swallow your pills.

Take all your medications as prescribed. If you are diabetic, check with the office about how to adjust your diabetic medications.

Wear comfortable clothes and shoes for walking. You will wear a hospital gown during the procedure. It is best not to wear any jewelry or valuables. Electrode patches will be attached to your chest and upper back. Men may have their chest hair shaved for electrode placement. A blood pressure cuff will be attached to your arm for monitoring during this test.

Procedure
The nurse will help you to the treadmill machine and the physician or physician's assistant will slowly start the treadmill belt and you will start walking at a comfortable stride. Every three minutes, the treadmill will move faster and the incline of the treadmill will increase. We will encourage you to walk for as long as possible so that we can obtain the maximal amount of information about your heart. When you feel that you can no longer continue, you will notify us and the treadmill will slow down and return to a flat level and then the treadmill belt will stop. We will help you back to the examining table as you may feel slightly dizzy. Your heart rate and blood pressure will continue to be monitored until your heart rate and blood pressure return to normal.

Follow-up care
The results of your treadmill test will be discussed with you and further recommendations will be made. As always, if you have any further questions, don't hesitate to call our office.

Microvolt T-Wave Alternans Test (m-TWA)

This is a noninvasive test that is used to evaluate a patient's level of electrical instability in the lower chamber of the heart (the ventricles). T-wave alternans was first described in the 1950's when it was observed that visible oscillations of the T-wave on the electrocardiogram (ECG) was an indication of an increased risk for dangerous ventricular arrhythmias-a very ominous warning. However, the ECG findings were very rare and of limited clinical utility. Recently, a new technique was developed using computer processing to evaluate for t-wave alternans that you could not see with the naked eye. This is called microvolt t-wave alternans (m-TWA). It has been shown that microvolt t-wave alternans is also associated with an individual's future risk of ventricular arrhythmias if it is seen within a certain range of heart beats. Almost all people have some m-TWA with very fast heart beats but m-TWA is clinically significant when it is present when the heart rate is less than 110 beats/min. Arrhythmia Associates were the first physicians in the Washington DC area to utilize m-TWA testing for our patients.

Preparation
We will ask you to refrain from using skin moisturizers or any bathing product that contains moisturizers (such as Dove soap) for 4-5 days prior to the procedure. Any ingredients that contain emollients to moisturize the skin affect our ability to record very subtle electrical signals from the electrodes on the chest. We may also advise you to discontinue your beta-blocker for several days prior as the test requires your doctor to increase your heart rate to over 100 beats/min and beta-blocker medications can limit this.

If you are diabetic, check with the office about how to adjust your diabetic medications. If you are on a blood thinner (anticoagulant), we may give you specific directions regarding this medication for the procedure, and the weeks leading up to the procedure.

Wear comfortable clothes. It is best not to wear any jewelry or valuables. Electrode patches will be attached to your chest and upper back. Men may have their chest hair shaved for electrode placement. The placement of the electrodes requires the nurse to mildly abrade the skin of your chest to remove any remaining skin oils that might hinder interpretation of the test. The preparation for this test can take 15-20minutes.

Procedure
There are two methods to perform m-TWA testing: exercise/walking testing and pacing testing. With a walking test, you will walk on a treadmill to slowly raise your heart rate to a rate greater than 100 beats/min. If your resting heart rate is already 100 beats/min, then walking may not be necessary.

A pacing test is generally performed in patients who already have a pacemaker. After the electrodes are correctly placed, the pacemaker is interrogated and we will temporarily program it to a set rate of 110 beats/min.

In either case, the data is obtained and then processed by a machine and the results will be interpreted by your doctors. The testing itself takes approximately 10 minutes. The interpretation of the test can sometimes be hindered by extra heart beats called atrial premature contractions (see APC's) or ventricular premature contractions (see VPC's) and the testing may need to be repeated for another 10 minutes.

Follow-up care
Your physicians at Arrhythmia Associates will review the available data and make further recommendations to you.

As always, if you have any questions, please call our office.

Tilt Table Test

This procedure is used to help uncover the mechanism for unexplained syncope. Often, the cause of syncope can be identified by careful review of the clinical history. In some cases, further testing is required to further clarify the mechanism of syncope in order to decide appropriate treatment.

Preparation
Do not eat or drink anything after midnight the evening before your procedure. If you must take medications, drink only small sips of water to help you swallow your pills.

Take all your medications as prescribed. If you are diabetic, check with the office about how to adjust your diabetic medications. If you are on a blood thinner (anticoagulant), we may give you specific directions regarding this medication for the procedure, and the weeks leading up to the procedure.

Wear comfortable clothes. You will wear a hospital gown during the procedure. It is best not to wear any jewelry or valuables.

Most likely, you will be able to go home after the procedure. You should bring someone with you to drive you home after the procedure.

Procedure
You will lie on a bed and the nurse will start an intravenous (IV) line into your arm or hand. This is so you may receive medications and fluids during the procedure.

The nurse will connect you to several monitors. Electrode patches will be attached to your chest and upper back. Men may have their chest hair shaved for electrode placement. A blood pressure cuff will be attached to your arm. Your heart rate and blood pressure will be carefully monitored while you are resting. We will then raise the table to a 70 degree incline. You may feel like you are falling forward but you will be strapped to the table to prevent this. Your blood pressure and heart rate will be carefully monitored. We will ask you to inform us if you feel dizzy or lightheaded. If you begin to feel symptoms, we will watch your blood pressure and heart rate even more closely to understand the mechanism for your dizziness. If the symptoms become worse, we will put the table back down flat and we will increase the fluids going into your arm and your symptoms should rapidly resolve.

Recovery
After the procedure, your referring doctor will be informed of the findings of this test and further recommendations will be made regarding treatment. You will be observed clinically and when you feel well the IV will be removed from your arm and you will be sent home. You may be provided some additional medications based on the results of your tilt table test

Follow-up care
Your referring physician will likely schedule a follow-up office appointment in a month or so after your tilt table test to see if the medical treatment is effective for you.

As always, if you have any questions, please call our office.