Cardiology Diagnostics Tests
What is an echocardiogram?
An echocardiogram (echo) is a test that uses high frequency sound waves (ultrasound) to make pictures of your heart. The test is also called echocardiography or diagnostic cardiac ultrasound.
An echo uses sound waves to create pictures of your heart’s chambers, valves, walls and the blood vessels (aorta, arteries, veins) attached to your heart. A probe called a transducer is passed over your chest. The probe produces sound waves that bounce off your heart and “echo” back to the probe. These waves are changed into pictures viewed on a video monitor. An echo can’t harm you.
Why do people need an echo test?
Your doctor may use an echo test to look at your heart’s structure and check how well your heart functions.
The test helps your doctor find out:
The size and shape of your heart, and the size, thickness and movement of your heart’s walls.
How your heart moves.
The heart’s pumping strength.
If the heart valves are working correctly.
If blood is leaking backwards through your heart valves (regurgitation).
If the heart valves are too narrow (stenosis).
If there is a tumor or infectious growth around your heart valves.
What is it?
An electrocardiogram — abbreviated as EKG or ECG — is a test that measures the electrical activity of the heartbeat. With each beat, an electrical impulse (or “wave”) travels through the heart. This wave causes the muscle to squeeze and pump blood from the heart. A normal heartbeat on ECG will show the timing of the top and lower chambers.
Why is it done?
An ECG gives two major kinds of information.
First, by measuring time intervals on the ECG, a doctor can determine how long the electrical wave takes to pass through the heart. Finding out how long a wave takes to travel from one part of the heart to the next shows if the electrical activity is normal or slow, fast or irregular.
Second, by measuring the amount of electrical activity passing through the heart muscle, a cardiologist may be able to find out if parts of the heart are too large or are overworked.
TMT / Treadmill Test / Exercise Stress Test
A stress test, sometimes called a treadmill test or exercise test, helps a doctor find out how well your heart handles work. As your body works harder during the test, it requires more oxygen, so the heart must pump more blood. The test can show if the blood supply is reduced in the arteries that supply the heart. It also helps doctors know the kind and level of exercise appropriate for a patient.
Why do doctor advice TMT?
A physician may recommend an exercise stress test to:
Diagnose coronary artery disease
Diagnose a possible heart-related cause of symptoms such as chest pain, shortness of breath or lightheadedness
Determine a safe level of exercise
Check the effectiveness of procedures done to improve coronary artery circulation in patients with coronary artery disease
Predict risk of dangerous heart-related conditions such as a heart attack.
Depending on the results of the exercise stress test, the physician may recommend more tests such as a nuclear stress test or cardiac catheterization.
What is a Holter monitor?
A Holter monitor is a battery-operated portable device that measures and records your heart’s activity (ECG) continuously for 24 to 48 hours or longer depending on the type of monitoring used. The device is the size of a small camera. It has wires with silver dollar-sized electrodes that attach to your skin. The Holter monitor and other devices that record your ECG as you go about your daily activities are called ambulatory electrocardiograms.
You may be asked to wear a Holter monitor to see if you have a slow, fast or irregular (uneven) heartbeat. Or, your doctor may use it to see how well your medicines are working to treat these problems. If you have a pacemaker and feel dizzy, your doctor may use a Holter monitor to find out if your pacemaker is working properly. This monitor has no risks and wearing it isn’t painful. The results of wearing a Holter monitor will help you and your doctor decide if you need more tests or medicines for your heart, or if you need a pacemaker or cardioversion procedure to restore a regular heart rhythm.
PFT can be done with 2 methods. These 2 methods may be used together and perform different tests, depending on the information that your healthcare provider is looking for:
- Spirometry. A spirometer is a device with a mouthpiece hooked up to a small electronic machine.
- Plethysmography. You sit or stand inside an air-tight box that looks like a short, square telephone booth to do the tests.
Should Your Sleep Be Evaluated?
To determine whether you might benefit from a sleep evaluation, ask yourself the following questions:
Do you regularly have difficulty getting to sleep or staying asleep?
Do you have a problem with snoring? Has anyone ever told you that you have pauses in breathing or that you gasp for breath when you sleep?
Are your legs “active” at night? Do you experience tingling, creeping, itching, pulling, aching or other strange feelings in your legs while sitting or lying down that cause a strong urge to move, walk or kick your legs for relief?
Are you so tired when you wake up in the morning that you cannot function normally during the day?
Does sleepiness and fatigue persist for more than two to three weeks?
If you answered yes to any of these questions, then a complete sleep evaluation should be considered
How does a home sleep test work?
*Most HSTs come as a kit with several parts and instructions for how to use them. The most minimal kit will include: *
A small recording device, usually a box
A nasal cannula (clear tubing inserted into the nostril to measure airflow)
A belt to wear across the chest to measure the chest’s breathing effort
A pulse oximeter (a finger clip which measures blood oxygen and pulse rate)
Additional devices in an HST kit might include:
A thermistor (a wire sensor that measures oral breathing)
A second belt to wear across the lap to measure the diaphragm’s breathing effort
A position sensor to indicate what side you are sleeping on at any given time during the study
A snoring sensor which measures throat vibrations indicate snoring
Each of these components is applied prior to bedtime; they usually require simple adhesion, but nothing painful.
The recording device, once the test is started, collects a variety of data—how many pauses in breathing occurred, how low the blood oxygen levels dipped throughout the night, any marked changes in heart and respiratory rates.
This data usually provides enough of an objective glimpse into the patient’s nighttime breathing patterns to help identify moderate to severe OSA.