How to use 1-lead ECG recorders to obtain 12-lead resting ECGs and exercise ("stress") ECGs
http://www.ndsu.edu/pubweb/~grier/1to12-lead-ECG-EKG.html
by James W Grier Department of Biological Sciences North Dakota State University Fargo, ND 58102-3400
Introduction
Although 1-lead ECG (EKG) recorders are normally used primarily for basic heart monitoring, checking for various arrhythmias, or simple educational or research purposes, they can also be used for looking at the effects of exercise on the ECG. One-lead recorders can also be used to accomplish full 12-lead recordings in a sequential manner.
New, low-priced, 1-lead handheld ECG recorders have become available for personal, home, and sports use, much as with home blood-pressure/pulse recorders or glucose testers for diabetics. They also are suitable in some emergency situations but only when used by medical or emergency personnel. Otherwise, they can be used by the general public for personal recording of information, such as for baseline information, routine monitoring, or during uncommon events, like with cardiac event recorders. The recordings can then be shown to the person's cardiologist or electrophysiologist or, for non-emergency or simple monitoring purposes, used by the person himself or herself if he or she is able to interpret them. (ECGs are complex and have a fairly steep learning curve. For a basic introduction, click here.)
One-lead ECG recorders may also be used for monitoring the heart in association with regular exercise, workouts, and sports activities. The actual recordings need to be done while the body is not moving, to avoid artifacts from the muscles. However, "resting" measurements can nonetheless be done during exercise and while the heart is responding to the exercise by briefly interrupting the activity long enough to obtain a recording or immediately after finishing the activity. Recordings can also be made while resting during the recovery period following exercise. The use of any ECG recorder for exercise, however, is somewhat akin to stress tests done in a clinic or hospital under medical supervision and should not be done at home if cardiac problems are suspected or might occur or if clear emergency or urgent situations exist (see disclaimer section below). Please consult a cardiologist if in doubt.
The purpose of this article is to explain how to use 1-lead (2 to 3 electrode contact) recorders in both exercise and 12-lead contexts. When using the recorder for exercise purposes, one might want to focus on a particular lead of the various 12 that are available, such as lead II or one of the chest leads (V1-V6). Thus, I will explain how to obtain the different 12 leads first and then one can choose which of them to use for measuring the ECG during exercise.
Important disclaimer: This information is provided for educational, sports-associated (by healthy persons), research, and non-emergency monitoring use only, not diagnostic or emergency uses by untrained persons. In the event of an emergency or suspected-emergency situation, appropriate medical help and facilities should be sought as quickly as possible. The only time that personal ECG recorders should be even considered in urgent, emergency situations would be if problems were to occur in remote locations to obtain useful information and/or while waiting for transportation and help, that is, when the use of the recorders would not delay possible help and might permit the collection of useful information for later use.
Source of 1-lead ECG recorders: The descriptions and information in this web page are based on handheld recorders from Favoriteplus.com, a medical equipment division of Favorite Imports LLC and a worldwide distributor of pulse oximeters, handheld ECG-EKG, & fetal dopplers. They are "an international distributor and global provider of medical devices for the hospital, emergency, home and specialist environments. Established in 1998, ... grown to be one of the most reliable worldwide distributors of new and innovative health products, medical devices and accessories." They have three models of handheld ECG recorders currently available, the FP-RMH, FP-ICH, and FP180 (PC-80). For further company information about the units and ordering, click here. For general comparisons and a review that I conducted of the three units, click here. I thank Favoriteplus for providing two of these recorders to me for purposes of comparison.
The following figure shows the three 1-lead handheld recorders used for this article, from left to right: ReadMyHeart (FP-RMH, hereafter referred to as RMH), InstantCheck (FP-ICH, referred as IC in the remainder of the article) and PC-80 (FP180). Top row closed, bottom row open.
...
Comments and Conclusions
Single-lead ECG systems not only work, but they work remarkably well for conducting both 12-lead and exercise ECGs. It must be noted, however, that the 12-lead results from 1-lead systems are sequential, not simultaneous as are the ones recorded with most standard 12-lead systems. Similarly, exercise recordings cannot be done continuously during the actual activity as with Holter units or standard stress-testing equipment. Instead, quick recordings must be made during brief interruptions of the activity, while the heart is still responding to the activity.
Of the three 1-lead handheld systems discussed in this article, the PC-80 produced the least satisfactory 12-lead outcomes. It does, however, detect beats against other muscle noise better than the other two during actual activity. Trying to make recordings during active movement, nonetheless, is noisy and messy with these simple systems regardless of which of the three is used. The PC-80 appears most suitable for its intended purpose of being able to quickly record arrhythmias (see the comparative review of these three 1-lead recorders).
If one is really serious (and has the equipment, or finances to obtain full, standard 12-lead or Holter equipment), the standard equipment still produces better results and the kinds of outputs that cardiologists and electrophysiologists are more accustomed to reading. Nonetheless, particularly for persons on a limited budget, wanting a simple home personal system, or wanting something very portable and handy, including for traveling, the small, handheld, 1-lead systems will do the job.
.END
No comments:
Post a Comment