Methods of registration of ECG

Normal ECG consists of three upward (positive) teeth, P, R, T, two directed downwards (negative) teeth Q and S, and non-permanent teeth U. Teeth are designated by letters of the Latin alphabet.

Fig. 10. Normal electrocardiogram (scheme).

Begins ECG (Fig. 10) with an upward spike P, consisting of hollow rising knee, a rounded top and a few more steeply descending downward knee.
For tooth R should horizontal or nearly horizontal line that ends with an irregular, is is usually very small, steeply descending down tooth Q. Interval P - Q - from the beginning, and P wave till the beginning of wave Q. Rising knee Q wave directly goes to the most high, upward spike R.
Rising knee R-wave rises very cool, forms a pointed top and goes into a little less steeply descending downward knee. The downward elbow R-wave directly goes into a downward fickle little tooth S.
For tooth S, and in his absence - by the R-wave usually follows a horizontal or nearly horizontal line - interval (segment) RS - So it was, when the wave's directly enters the hollow rising and then falling with usually rounded tip of the tooth So For the T wave with a small interval sometimes should prong U.
For the T wave, and in the presence of U waves " over the past should horizontal (isoelectric line corresponding to the period when the heart is in diastole and measuring system of ECG does not give vibrations - the interval T - R.
ECG consists of atrial and ventricular complexes.