A sinus rhythm is any cardiac rhythm where depolarization of the cardiac muscle begins at the sinus node. Sinus rhythm is necessary, but not sufficient, for normal electrical activity within the heart. ECG also fall within designated normal limits, giving rise to the characteristic appearance of the ECG when the electrical conduction system of the heart is functioning normally. However, other sinus rhythms can be entirely how to read ecg step by step pdf in particular patient groups and clinical contexts, so the term is sometimes considered a misnomer and its use is sometimes discouraged.
Example of a sinus rhythm with bifascicular block. Other types of sinus rhythm which can be normal include sinus tachycardia, sinus bradycardia and sinus arrhythmia. Sinus rhythms may be present together with various other cardiac arrhythmias on the same ECG. ECG cannot therefore be classed as showing a sinus rhythm.
In general, each P wave in a sinus rhythm is followed by a QRS complex, and the sinus rhythm therefore gives rise to the whole heart’s depolarisation. ECG measurements are also normal. Regular rhythm, with less than 0.
16 second variation in the shortest and longest durations between successive P waves. P waves must be round, all the same shape, and present before every QRS complex in a ratio of 1:1.
Normal PR interval, QRS complex and QT interval. QRS complex positive in leads I, II, aVF and V3-V6, and negative in lead aVR. Evaluation of the P Wave Axis in Patients With Systemic Lupus Erythematosus”.
A male patient walks on a stress test treadmill to have his heart’s function checked. The stress response is induced by exercise or by drug stimulation.