Cardiology Exams

Electrocardiogram (ECG), Echocardiogram (ECHO), and Holter Monitor

Although strokes result from some type of brain damage, many of the causes of stroke come from outside of the brain. The main organ in the body where the cause may originate and can be monitored is the heart.

Electrocardiogram (ECG)

An ECG (also sometimes referred to as an EKG) is a test done to analyze the electrical activity of the heart as it beats. During the process of a heart beating, electrical waves travel throughout the heart, and these waves of electricity can be measured and monitored to observe whether the heart is functioning normally of there are some unusual aspects to the beating such as an arrhythmia. Physicians from these tests can determine even the strain the heart is being put under, as well as whether the heart has increased in size (a common effect on the heart among people with chronic high blood pressure).


“Electrical activity pattern across various heartbeats”. Image. The Biology Corner 2001. 29 May, 2013


Although ECG’s are meant to measure the electrical activity of the heart, they do so indirectly by measuring the electrical activity that flows from the heart across the skin. For this exam, you may be doing some type of activity or lying down still depending on what aspects of heart function the physician would like to test. You will have 12 – 15 electrodes placed at various specific areas along your body which will be used to record the data.

Echocardiogram (ECHO)

An ECHO is an ultrasound exam in which the entire heart is imaged via sound waves. The exam is used to observe the heart, analyze its characteristics as well as determine if there are any noticeable physical impairments in the heart, including blockages, risk of blood clots forming, and enlargements.


“ECHO example” Image. Heart Failure Matters. 2007. 29 May, 2013


An ECHO is a fairly simple exam in which you will have a gel applied on your chest. An ultrasound transducer is then used to emit sound waves and retrieve them back. The sound waves that return are then converted to an image that is analyzed by a physician.

Holter Monitor

A holter monitor is a test that is used to measure heart rhythm over a long period of time (usually starting at 24 hours). While wearing a holter monitor, the heart rate and rhythm is recorded. The recorded information is later analyzed by a physician. Holter monitoring is important in identifying any arrhythmias that may appear throughout the day, especially in some cases where arrhythmias are not constant but appear erratically. The data retrieved through a holter is shown as electrical activity, similar to an ECG.


“Holter Monitor”. Image. 2010. 29 May, 2013


Holter monitoring requires you to have a few electrodes placed on your chest, which are connected to a small device (perhaps attached to your belt) which records the data. As the device is not overbearing, you can continue performing your daily activities during the test.