A combination of the Q wave, R wave and S wave, the “QRS complex” represents ventricular depolarization. This term can be confusing, as not all ECG leads contain all three of these waves ...

before sharp waves of activity in the ventricles, or QRS waves. With Mobitz type 1 second-degree heart block, the PR intervals get longer, and QRS waves are delayed and then dropped, which happens ...

These ECG voltage attenuations are of extracardiac mechanism, and impact the amplitude of QRS complexes, P-waves, and T-waves, occasionally resulting also in shortening of the QRS complex and QT ...

The atrial rate is indicated by the frequency of the P waves. The ventricular rate is indicated by the frequency of the QRS complexes. In the absence of disease, the atrial rate should be the same ...

6,11–14 A junctional or nodal rhythm occurs when the QRS rate is faster than the resting P wave or sinus rate which is slowed in athletes due to increased vagal tone (figure 4). The QRS rate for ...

A 76-year-old woman presents with a persistently rapid heart rate that she attributes to her pacemaker. What does the ECG show?

Normal ECGs include common, training-related findings in athletes such as high QRS amplitude meeting voltage criteria for ... These include findings suggestive of cardiomyopathy such as T-wave ...