Many cardiac diagnostic tests are performed at Bluewater Health by Cardiovascular Technologist and Cardiac Sonographers, including:

Device Interrogations

A device interrogation (pacemaker check) is booked after the initial pacemaker insertion to assess the function and battery life of the pacemaker. These appointments may be booked at 1 month, 3 month, or 6 month intervals.


A standard echocardiogram (echo), also known as a transthoracic echocardiogram (TTE), is an imaging modality that uses ultrasound to create images of your heart. It is a diagnostic test used to examine the structure and function of the heart. An echocardiogram determines the size of the hearts chambers, how well the heart contracts and relaxes, and how each valve functions.

At times, it may be difficult to obtain clear images during your echocardiogram. If this is experienced, the Cardiac Sonographer may suggest using an enhancing agent (Definity) in order to improve image quality and provide greater detail of the structure and function of your heart.

An Agitated Saline study is used as an additional component to a regular transthoracic or transesophageal echocardiogram in order to assist in detecting an intracardiac shunt. This test involves agitating saline between two syringes and then administering that agitated saline through a peripheral intravenous (IV) catheter located in the arm.

ECG (Electrocardiogram)

An electrocardiogram (ECG or EKG) is a test that checks how your heart is functioning by measuring the electrical activity of the heart.

Outpatient ECG’s ordered by a Cardiologist or Primary Care Provider can be performed on a walk-in basis, Monday-Friday 8am-4pm.

Exercise Stress Test

An exercise stress test involves a person exercising on a treadmill at increasing stages of difficulty. While on the treadmill, the person's heart rate, blood pressure and electrocardiogram are monitored.

Holter Monitoring

Holter monitoring is primarily an outpatient test. The Holter monitor is worn by the patient for 24hr/48hr/72hr or 7 days. The heart's rhythm is recorded electronically on the device during this time. It is later scanned by the Cardiovascular Technologist and reviewed by an Internist or Cardiologist.

Transesophageal Echocardiogram

A Transesophageal Echocardiogram (TEE) is a test in which a small transducer is inserted through the mouth into the esophagus. This technique allows the doctor to assess the structure and function of your heart in more detail without interference from the ribs and lungs. A TEE is often ordered when the results from a standard echocardiogram are insufficient, or when your doctor wants to take a more detailed look at your heart.


Level 1, Norman Building
Bluewater Health, Sarnia
89 Norman Street, Sarnia, Ontario N7T 653

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Monday to Friday, 8:00 am to 4:00 pm
Closed Saturday, Sunday, Statutory Holidays
Telephone: 519-464-4400, Ext. 5282
Fax: 519-464-4558

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