Diagnostic Testing Oakville

Diagnostic Testing

Types of Diagnostic Testing

electrocardiogram (ECG) waves

Electrocardiogram (ECG)

An Electrocardiogram, which is sometimes called an ECG or EKG, is a test to determine  the electrical activity of the heart.  The heart is controlled by an electrical system, that causes the heart to contract with each heartbeat. An ECG uses sensors (electrodes) that are placed at various locations on the chest and limbs, to record the electrical signals of the heart.  These electrical signals are visualized as waves, and provide information to the cardiologist about any problem’s in your heart’s electrical conduction system.

Holter Monitor

A Holter monitor is a type of portable electrocardiogram, which records the continuous electrical activity of the heart for a certain period of time. Your cardiologist will determine the length of time you need to wear this monitor, such as 24 hours, 48 hours, 72 hours or 7 days, depending on the clinical concern.   The purpose of the Holter monitor is to detect any abnormal electrical disturbances (such as arrhythmias or conduction delays), that may need to be managed accordingly.

woman connected to a holter monitor
echocardiography machine


Echocardiography, also called an “Echo,” is a sophisticated imaging modality that uses high frequency sound waves to visualize the contractility of the heart and Doppler technology to determine the flow of blood through the heart chambers and valves.  Echocardiography is able to visualize the structure of the heart at rest, with the additional benefit of not using radiation, unlike some imaging modalities, including CT-Scans or MRIs. 

Stress Test

A treadmill stress test involves walking on a treadmill, while connected to a continuous ECG monitoring device. The treadmill speed and inclination are increased every 3 minutes, with a goal of achieving at least an 85% target heart (this is calculated based on the patient’s age). Exercise may be stopped earlier with the onset of chest discomfort, marked shortness of breath, weakness, or a drop in the blood pressure. It can also be stopped with the onset of an abnormal heart rhythm (an arrhythmia) or ECG changes suggesting impaired flow of blood to the heart muscle. This test is designed to “Stress” the heart in a monitored setting, and a cardiologist is present during the study for safety. 

doctor smiling at the camera ready to perform a stress test
doctor reviewing a stress echo on a computer

Stress Echocardiography

A stress echocardiogram is a combination of an exercise treadmill test with an echocardiogram. The purpose of the stress echocardiogram is to evaluate for coronary artery disease, but it can also be used to evaluate heart failure, including reduced left ventricular contractility or impaired relaxation, valvular abnormalities, and pulmonary hypertension. The study helps your cardiologist determine the best management strategy, as well as response to therapy.

Cardiopulmonary Exercise Testing

The Cardiopulmonary Exercise Test, which is sometimes called a “CPET or CPX”,  measures how well your heart and lungs are performing both at rest and during exercise. This helps your cardiologist determine the amount of oxygen your body is using, the amount of carbon dioxide your body is producing and your breathing pattern. It is an excellent diagnostic tool to determine the cardiopulmonary source of shortness of breath. The results of this study can help diagnose Pulmonary Artery Hypertension, as well as determining the cardiovascular fitness before and after engaging in a structured exercise program, particularly for our heart failure population. 

doctor doing an exercise test on a patient. patient is using the treadmill while connected to machines for testing
photo of a blood pressure monitor displaying 120

24 hour Ambulatory Blood Pressure Monitor

Ambulatory blood pressure monitoring measures your blood pressure over a 24 hour period, while you are awake and while you are sleeping. It involves wearing a blood pressure cuff, with a small device which is attached to a strap or a belt. The cuff inflates every 15-30 minutes in the daytime, and every 60 minutes at night. The data collected provides information on the average blood pressure and heart rate, blood pressure distribution patterns during the daytime and nocturnal periods, magnitude of the nocturnal decline in blood pressure, and other important details about cardiovascular risk. 

Still have a question about diagnostic testing? Speak to your doctor about a referral to the Chahal Cardiovascular Centre for a Cardiovascular consultation.