Electrocardiogram (ECG)
While electrocardiograms (ECGs) are a useful tool in diagnosing heart conditions, there are some limitations and shortfalls to be aware of:
ECGs are a snapshot in time
An ECG provides information about the heart's electrical activity at the time it was taken. It does not provide information about the heart's activity before or after the recording. Therefore, if a heart condition is intermittent, an ECG taken during a period of normal activity may not show any abnormalities.
False positives and false negatives
ECGs can sometimes produce false positives or false negatives. False positives occur when an ECG shows abnormalities that are not actually present, while false negatives occur when an ECG fails to detect a heart condition that is present.
Limited Information
An ECG provides information about the heart's electrical activity, but it does not provide information about the heart's structure or function. To get a more complete picture of the heart's health, other tests such as echocardiography, cardiac MRI, or stress tests may be necessary.
Operator-Dependent
The quality of an ECG can depend on the skill and experience of the technician performing the test and the physician reading it, as well as the positioning of the electrodes and the patient's body.
Not suitable for all heart conditions
While ECGs are useful for diagnosing certain heart conditions, they may not be helpful in diagnosing others. For example, an ECG may not be able to detect a chronic blockage in a coronary artery, which is often diagnosed through other imaging tests.