History

The GE 12SL ECG analysis program is a computer program for analyzing simultaneously acquired 12-lead ECGs. It makes precise measurements of recorded cardiac signals, then provides an interpretation of the ECG waveforms using classic and newly developed ECG interpretation criteria for both rhythm and morphology. Since its introduction in 1980, the 12SL ECG analysis program has set the standard in computerized ECG analysis and continues to do so today. GE has also introduced the capability to analyze pediatric ECGs by incorporating age driven criteria capability for patients less than 16 years of age. In addition, the capability to acquire, measure, and store 15 leads of simultaneous data was introduced. GE Medical Systems has continued to set the ECG analysis standard to higher levels and leads developments in the field of computerized ECG analysis through a continuous process of program updating and refinement that is supported by extensive clinical evaluation and active collaboration with many of the world's leading cardiologists. Additionally, the 12SL program works in synchrony with the Catalsyt MUSE® system's serial comparison program, which uses both 12SL program statements and waveform measurements to interpret clinically significant ECG changes occurring between the current and first previous ECG of a patient.

12SL development strategy

The 12SL ECG analysis program has continued at the forefront of computerized ECG analysis for two very important reasons. The first is that we receive continuous clinical input from leading cardiologists through the annual ECG analysis seminar, at which a group of over 50 top consulting cardiologists and physicians from around the world along with GE's own staff of ECG analysis algorithms research and development engineers exchange ideas, aimed at continued improvement and fine-tuning of the 12SL ECG analysis program's accuracy.

Secondly, GE Medical Systems has made a commitment to acquire an unmatched collection of clinically correlated and "gold standard" validated databases which are used to evaluate, verify and improve the program's performance. In addition, the results of testing the program against these "gold standard" databases makes the accuracy values more useful to the practicing. In addition, we are continually in contact with program users on a day-to-day basis through feedback provided via user mail and customer comments forwarded from our dedicated Cardiology sales force. Our highly qualified staff of engineers have developed techniques to quickly evaluate accuracy and assess improvements made to the program on very large databases. The result of this regular clinical input and extensive analysis on large databases has allowed for continued and steady improvements to an already state-of-the-art program.

For the less experienced interpreter, such as the general or family practice physician

Provides an automated second opinion that has "gold standard" verified accuracy.

May suggest additional findings not initially detected and encourages more careful, targeted review of the ECG tracing.

Provides feedback that may help the user to become more proficient in ECG interpretation.

For the expert, more experienced interpreter

Saves time spent reading the ECG.

Provides a back up opinion that may help prevent the expert in a hurry from overlooking subtle findings.

Reduces intra-over reader variability and leads to increased agreement among a group of physicians which in turn makes the confirmed diagnosis more valuable to other health care providers.

For all users

Provides accurate, validated measurements of heart rate, axis, intervals and durations.

The pediatric computerized analysis provides age driven interpretation criteria to users not trained in the interpretation of pediatric ECGs.

Studies indicate that physicians aided by computers produce the best interpretation of ECGs.¹

Objectivity, through the use of the 12SL program's uniform consistent interpretation criteria.

Reproducibility, due to the fact that each physician reads ECGs differently. The computerized algorithm provides consistent interpretation on each and every ECG.

Efficiency, the computerized acquisition and analysis takes less than 15 seconds, allowing many ECGs to be performed in a short period of time minimizing the amount of time required of the physician.

New interpretive information, the 12SL program provides measurements that are difficult and time consuming to calculate, which may now be newly used to interpret existing clinical conditions that were not in use when the physician was in training.

GE Medical Systems has pioneered the technology and expertise to move the 12SL program out of the hospital and to the patient. This has been done by making the 12SL program operate on a variety of platforms.

Currently the 12SL program exists in the:

Pre-hospital environment

Emergency department

General hospital departments

CCU/ICU

Exercise testing labs

Clinics

Physicians offices

It should be made clear that a computerized analysis is not a substitute for physician interpretation. There are two reasons for this. First, statements of accuracy need to be viewed from a statistical perspective. Although accuracy levels may be high, outliers can and will exist. Second, a computer does not have the ability to include the entire clinical picture of the patient. A person with organic heart disease may exhibit an ECG within normal limits. Conversely, a normal individual may have an abnormal appearing ECG. The ECG, therefore, must always be reviewed in light of the surrounding clinical circumstances.

For more information or a copy of the 12SL ECG analysis program Statement of Validation, ask your GE Medical Systems sales representative, call us at 1-800-558-5120.

¹Laks MM, Sylvester RHS. Computerized electrocardiography - an adjunct to the physician. N Engl J Med 1991;325:1803-1804