Electrocardiography is a method of monitoring and recording the heart’s electrical activity using a technologically advanced machine and attaching electrodes to the patient’s body. Sometimes an electrocardiogram (ECG or EKG) is performed as part of a required health evaluation for certain professions. Frequently, an ECG is used as a screening test to help diagnose cardiovascular conditions. Suspected heart attack, suspected structural heart abnormalities, suspected pulmonary embolism, perceived heart murmur, perceived heart dysrhythmias, unexplained seizures, unexplained fainting, suspected electrolyte imbalances and evaluating effects of cardiac medications are some reasons for performing electrocardiography.
Usually, an electrocardiogram takes less than twenty minutes to complete. Sometimes, continual or extended ECG monitoring is used on surgical patients undergoing general anesthesia, critically ill patients and patients with suspect or unpredictable cardiac activity. In some cases additional information is needed and patients will be asked to wear a portable ECG monitor (a Holter monitor) 24 hours a day for a designated period of time.
The Holter monitor is a small, easy to use, portable device used to continually record cardiac electrical activity for an extended period. Since certain cardiovascular disease symptoms and atypical cardiac activities occur intermittently, 24 hour monitoring can be quite helpful with determining a correct diagnosis. After evaluating your risk factors, symptoms, various test results and your initial ECG recordings, Dr. Alonso may recommend a Holter monitor to help ensure an accurate diagnosis and to help determine the best course of action. Patients are usually requested to wear the device, 24 hours a day, for one to three days while continuing normal daily activities.
The Holter monitor is like a miniature electrocardiographic machine. It operates similarly to the larger device; however, it is smaller and allows for continual ambulatory monitoring. Electrodes are attached to the patient’s chest for recording heart activity in the same way as a regular ECG. The portability and 24 hour monitoring capability of the Holter monitor can provide valuable information that may not be evident from a traditional ECG.
Another type of portable monitor is called an event monitor. Although this type of monitor is worn 24 hours a day, it does not record continuously. An event monitor is used to record cardiac activity at the time symptoms occur. A patient may need to wear this type of monitor for up to one month and keep a journal of all symptomatic occurrences during normal daily activities.
An insertable cardiac monitor is another type of monitor used to continually record a patient’s cardiac activity. Patients with unexplained fainting spells are good candidates for an insertable monitor. During a simple procedure, this small device is inserted just below the skin in the chest area. The insertable cardiac monitor operates with an accompanying patient assistant (tool) that is placed over the heart when symptoms are present.