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 Cardiology Diagnostics

Services Include:

An appointment is required for all tests with the exception of ECG. To book an appointment for Cardiac Diagnostic Tests our booking line hours are: 7:30am to 3:30pm Monday to Friday. We can be reached at 905-813-4545. Referrals can also be faxed to 905-813-4156

Graded Exercise Stress Test


  • To diagnose the presence or absence of coronary artery disease.
  • To monitor the progression of ischemia, or the absence of ischemia following treatment.
  • To detect heart and circulatory problems such as irregular heartbeat, partially blocked arteries or heart attack risk that might not be detected while a patient is at rest.

The Test:

You will be asked to sign a consent form prior to the start of the procedure. Heart waveforms and blood pressure are monitored while walking or running on a treadmill. The test always starts slowly, however, individuals will be asked to exercise for as long as they are able. The test is performed by a Cardiology Technologist who is specialized in this area of testing, and under the supervision of a Cardiologist. The test, including set up, exercise time and recovery is usually 30-45 minutes in length
*Please note for paediatric patients under the age of 18 years.  A referral for the stress test must come from the Paediatric Cardiologist at CVH.

Graded Exercise Metabolic Stress Test


  • To set up an individualized exercise prescription.
  • To monitor the respiratory response to exercise
  • To assess Pulmonary or Cardiac Disease

The Test:

You will be asked to sign a consent form prior to the start of the procedure. Heart waveforms, blood pressure and oxygen saturation and breathing are monitored while you exercise on a treadmill. You will be asked to breathe through a mouthpiece that will measure the gas to determine the oxygen consumed and carbon dioxide produced. You will be encouraged to exercise to your limit and you will advise the Cardiology Technologist if you experience any symptoms during the exam. The duration of the test including set up, exercise time and recovery is usually 45 minutes in length.

Preparation for Graded and Metabolic Stress Testing:

No food, caffeine or cigarettes 2 hours prior to testing. Bring comfortable exercise clothing and shoes. You must bring a complete list of medications.

Nuclear Cardiology

Nuclear Cardiology is a medical specialty that utilizes small doses of radioactive injections for diagnosis, maintenance and prevention of coronary artery disease (CAD). It uniquely provides important information about the physiology and anatomy of the heart using such procedures as myocardial perfusion imaging (MPI) and radionuclide angiograms (RNA/ SYMA/MUGA).

Myocardial Perfusion Imaging:


  • To determine the extent and severity of coronary artery disease.

The Test:

Images are taken of the heart at rest and following either a treadmill exercise or pharmacological stress agent called Persantine.  Safe radioactive intravenous injections such as Thallium, Cardiolite or Myoview are used so that these images of blood flow to the heart muscle can be taken by a gamma camera. The procedure takes 4 to 5 hours to complete. You will be asked to sign a consent form prior to starting the test.


Have a light breakfast the morning of the exam; do not consume any caffeinated products (coffee, tea, chocolate, soft drinks) for 24 hours prior to the test. Bring a list of all current medications, and comfortable clothes and shoes.

Resting Syma


  • To measure the contractile function of the heart muscle, mainly the left ventricle.
  • To assess wall motion, cardiac enlargement, hypertrophy, and pumping (ejection fraction).

The Test:

Two injections are given about 20 minutes apart (pyrophosphate and a radioactive tracer). A gamma camera is then used to image the heart.  The test takes about 45 minutes and there are no pre-test instructions.



Transthoracic Echocardiogram (ECHO)


  • To assess the structure and function of the heart and related structures through ultrasound.
  • To determine how strong a person’s heart muscle is moving as well as how blood flows through the heart and valves

The Test:

You will be asked to lie down on an examination table in a dark room. The test is performed by an Echo Sonographer who will apply Vaseline like gel to your chest to help move the transducer. This will provide images of your heart.  For adults the test generally takes from 30 to 60 minutes and there is no preparation required prior to the test.

Sedated Paediatric Echocardiogram (1 month to 3 years old)

Sedation is required for children aged 1 month to 3 years of age. A pre sedation consultation with a Paediatrician must be done within 3 weeks prior to the ECHO. If a family physician is ordering the study. Patients must be referred to the paediatric medicine clinic at CVH for the pre sedation consult.  Allow 2 to 3 hours for sedation studies.  Sedation may be cancelled at the discretion of the paediatric cardiologist.


Children that are being sedated must not have food, milk or formula for six hours prior to their appointment time. Breast milk is allowed up to four hours prior and clear fluids or water is allowed up to two hours prior to the appointment time. Once your child wakes up in the morning try to keep them awake. Bring a favorite blanket or pacifier or anything else that may help your child go to sleep. You may also bring a favorite DVD to watch.

Paediatric Echocardiogram (4 to 17 years)

No preparation is required for paediatric patients over 4 years of age.  Allow one hour for the test.  For younger children bring something that will help them lay still for the hour.

Transesophageal Echocardiogram (TEE)

A TEE is another form of Echocardiogram using an ultrasound tube which is passed through the mouth and throat and is easily swallowed. It allows us to see clear pictures of the heart and related structures from the inside of your body. Your Cardiologist may request this exam when adequate images cannot be obtained during a standard Echocardiogram.
Sedation is required for this procedure.


  • To assess the structure and function of the heart and related structures

The Test:

You will be asked to sign a consent prior to the test being performed. The test is performed by a Cardiologist and Echo Sonographer You will be given sedation through an Intravenous as well as analgesic agents to relax your throat and reduce any discomfort this test may cause.  Some patients may experience a sore throat for a few days after the procedure. The procedure takes 15 to 20 minutes but expect to be in the department for approximately two hours.


You must have nothing to eat or drink for 12 hours prior to the test. Due to the light sedation you will be receiving you will not be permitted to drive yourself home after the study.  Please arrange for someone to accompany you and drive you home following the procedure.

Stress Echocardiogram

Echocardiography enables dynamic evaluation of cardiac structures and function at rest and during stress provoked by exercise or pharmacologic agent. Echocardiographic imaging performed during or immediately after stress is used primarily to detect the presence (or absence) and extent of ischemia secondary to obstructive coronary artery disease and to measure or estimate overall ventricular systolic function


  • To establish diagnosis and risk stratification for patients with known or suspected coronary artery disease. The presence and extent of ischemic myocardium, as well as dysfunctional but viable myocardium, can be evaluated
  • To evaluate such conditions as mitral stenosis, mitral regurgitation, pulmonary hypertension and hypertrophic cardiomyopathy


  • Light meal prior to the test. Preferably, do not eat or drink three hours prior to the procedure
  • Do not drink or use products containing caffeine 24 hours prior to the test
  • Specific heart medicines (such as beta blockers) may need to be stopped 24-48 hours prior to the test. Check with your doctor about specific instructions regarding medications before the test. Do not stop taking medications without consulting your doctor
  • Wear comfortable clothing and shoes that are suitable for exercising on a treadmill or bike
  • The examination will take approximately 1.5 to 2 hours

Holter Monitor

A Holter monitor is a small recorder that records continuous heart rate and rhythm from the heart. Depending on your symptoms your physician may ask you to wear the monitor for 24 to 48 hours.


  • Palpitations
  • Irregular heartbeat
  • Cardiac arrhythmias
  • Check Pacemaker Function
  • Check Heart Medications

 The Test:

The technologist will prepare your chest for the monitor. Then they will apply sticky electrodes to your chest. The electrodes will be connected to lead wires and the holter monitor. You will leave the hospital wearing the monitor and continue your daily activities while recording any symptoms in a diary that will be provided to you.
Do not take a shower or take a bath while wearing the monitor. The monitor will not cause any symptoms.

Loop Monitor (Cardiac Event Recorders)

Cardiac event recorders are small portable devices worn by a patient during normal activity for up to 14 days. The device has a recording system capable of storing several minutes of the individuals electrocardiogram (ECG) record. The patient can initiate ECG recording during a symptomatic period of arrhythmias or the device can be set so it automatically trigger an ECG recording when certain arrhythmias occur. The primary reason using the cardiac event monitor is to diagnose and evaluate cardiac arrhythmias. Once the monitor has a recording, results can also be sent in by transmitting the ECG to the hospital via telephone transmission, a landline telephone is required to do this.


  • To document an arrhythmia instead of using a Holter Monitor or if a Holter Monitor fails to document suspected arrhythmia.
  • To document the benefit after initiating drug therapy for an arrhythmia
  • To document the recurrence of an arrhythmia after discontinuation of drug therapy
  • To evaluate syncope and light headedness
  • To document the results after an ablation procedure for arrhythmia

Preparation for Holter Monitor & Loop Monitor:

Wear loose comfortable clothing or a button up top to allow easy access to your chest (one piece clothing is not recommended) Bring a list of all current medications; do not apply any lotions to your chest.   Since you cannot get the monitor wet while you are wearing it, showering prior to set up is preferred by most individuals. You will spend approximately 30 minutes for your appointment.

Borrowing Agreement for Monitors

You will be asked to sign a borrowing agreement form to take responsibility for the equipment when leaving the hospital. The monitors will be returned to the Cardiopulmonary Department to allow the technologist to download the information from the monitors for the Cardiologist to review.

Ambulatory Blood Pressure Monitoring:


  • To evaluate your blood pressure response to your activities of daily living.

The Test:

Your blood pressure will be monitored for up to 22 hours. A blood pressure cuff around your arm will measure your blood pressure every 30 minutes during the day and 60 minutes at night


Bring a list of all current medications, Wear comfortable loose clothing. There is a $75 fee for this test as it is not covered by OHIP.

Electrocardiogram (ECG)

An ECG is done to assess the electrical activity of your heart at one point in time. 

The Test:

You will be connected to the ECG machine with 12 sticker electrodes that are placed on your chest and asked to lie still for several seconds. The test takes under 5 minutes.
No appointment is necessary and there are no pre-test instructions.