INTRODUCING ARRHYTHMIA DIAGNOSIS
Let us talk about arrhythmia diagnosis. Most cases of arrhythmias do not occur frequently thus it is difficult to diagnose it. The doctor will utilize questions and investigations to arrive at a diagnosis. The flow is from history taking to physical examination and on to tests that help to make the diagnosis. Some of the tests done are those that will actually precipitate an arrhythmia so the doctor can observe it.
To get the right arrhythmia diagnosis, ensure that you are as detailed as possible when telling the doctor about the symptoms you have, questions asked usually include:
- Any feeling of an increased heartbeat
- Light headedness or dizziness
- Shortness of breath
The timing and frequency of occurrence of the arrhythmia can also be asked about. Other co-morbidities will also be ruled out. Certain diseases such as heart disease (including hypertension), diabetes and thyroid gland diseases may also lead to arrhythmia. Medications are also implicated in the causation of arrhythmia so do well to tell your doctor about any drug you are taking whether it is over-the-counter drug or prescription-only drugs including vitamins, minerals and herbal supplements you take. Other contributory factors include smoking, excessive alcohol consumption, intake of other drugs and the degree of stress you face.
The doctor is also interested in the family history. He or she will ask about family history of hypertension, diabetes, sudden death or arrhythmias especially in a first degree relative. Just tell the doctor about any family condition that has been noticed. During examination, the doctor conducts a cardiovascular system examination by listening to the heart rate or rhythm and also does the following:
- Listens for a heart murmur which is an abnormal sound produced by turbulence during blood circulation
- Examines the pulse and counts the heart rate at rest
- Examines for leg swelling which may be indicative of a heart failure or heart disease
- Requests for some blood tests to be done which are indicative of a heart disease or points towards a thyroid disorder
These are the initial procedures that are done but later on, the doctor orders for some diagnostic tests that either affirm or nullify the diagnosis.
DIAGNOSTIC TESTS FOR ARRYTHMIA
Several tests are employed by a doctor to make a diagnosis of arrhythmia. The heart may have to be monitored over a time span so that once an arrhythmia occurs, it can be detected. Some tests attempt to trigger an arrhythmia so the doctor can observe while others simply seek out things or conditions that are likely to cause an arrhythmia. Below are some tests employed in arrhythmia diagnosis:
It is a test used most frequently to make a diagnosis of arrhythmia. It generally measures the electrical activity of the heart. It can show how fast the heart beats, the heart rhythm, strength of the signals and timing of the signals as they pass through the heart. The electrodes take a record of the timing and duration of the heart beat. Here is a comprehensive guide on ECG for nurses.
It is a form of ECG that is portable and can be worn for days. The conventional ECG can be done over a short time in a doctor’s office. There are some patients who have symptoms that are not easily picked up while at the hospital or those who cannot stay long enough for the signs to emerge and so they may need to wear this halter monitor which will record the electrical activity in the heart over some days.
An event monitor is just like a Holter monitor (an ECG monitor). One is able to proceed with daily activities when it is worn. It only begins to take a recording when symptoms of arrhythmia start and the person wearing it is mostly aware of the time the recording starts. This is advantageous as it only records the electrical activity of the heart during an episode of arrhythmia.
Transthoracic echocardiogram (TTE)
A TTE utilizes sound waves to produce an image of the heart. It is a non-invasive procedure that is done by putting a sonography probe on the chest and capturing some images of the heart through this chest wall. This enables the doctor to visualize the heart and its chambers for any functional abnormality.
Here, sound waves are sent through the esophagus to create a picture of the heart. Unlike in TTE, here the sound waves pass through the esophagus and mostly create a picture of the heart valves and the back side of the heart. However, this test can only be conducted if the patient is sedated so the doctor can pass the probe easily without resistance and visualize the heart.
CT SCAN OR MRI
A computed tomographic scan (CT scan) of the heart or magnetic resonance imaging (MRI) of the heart are procedures that are done to find out the likely precipitants of an arrhythmia by visualization of the structure of the heart. They are non-invasive procedures. In an MRI, one lays on a table inside a cylindrical-shaped machine and the image of the heart is produced by the signals gotten when the magnetic fields arrange atomic particles in the body cells. For a CT scan, one lays on a table inside a circular machine and this machine rotates around the person’s body to get a picture of and take X-rays of the heart and chest.
Electrolyte imbalances will be checked for especially those which very high or low levels of it can precipitate an arrhythmia. Sodium and potassium are usually the electrolytes checked. Other blood tests can be done to check for the functionality of the thyroid gland as too high or too low levels can trigger an arrhythmia.
Some arrhythmias are noticed more when the heart is actively working such as during an exercise rather than when it is at rest. You may have to exercise within the hospital environment so the doctor can watch out for an arrhythmia by monitoring the heart rate on an ECG machine. For those who are not able to exercise or have difficulty exercising, the doctor will give medications that will cause the heart rate to be as that gotten when you would exercise.
Tilt table test
If you are the type that experiences fainting as part of your symptoms then the doctor can put you through this test to check for an arrhythmia. First, you will lie supine on a table and the table will be slowly lifted to 90 degrees at a standing position. The doctor watches the activities of the heart on an ECG, monitors the blood pressure level and the nervous system readings as the table is moved from a flat position.
Here, a slim, flexible tube known as a catheter is put into a blood vessel either from the arm, groin or neck. The doctor monitors blood circulation through the cardiovascular system when a special dye is introduced into the X-ray machine used for this visualization. Obstruction to blood flow or leakages in the circulation are usually the things checked for.
Electrophysiological mapping and testing
It is similar to coronary angiography in that it also makes use of a tiny flexible catheter to map out the inner functionality of the heart. The only difference here is that there are electrodes on this catheter which stimulate the heart and a recording of how the impulses spread across the heart is done by the machine. This enables the doctor to detect any leakage or obstruction in impulses.
Implantable loop recorder
This device is placed beneath the skin of the chest to recognize and record any abnormality in the heart’s rhythm. It is best for patients whose symptoms do not occur frequently.