The Q-wave represents the first activity of the ventricular depolarization and is usually the first negative deflection after the P-wave in the complete complex.

It is usually the central and most visually obvious part of the tracing in other words, it's the main spike seen on an ECG line. The QRS complex is the combination of three of the graphical deflections seen on a typical electrocardiogram (EKG or ECG). This segment shows the time it takes from the end of the P-wave to the beginning of the ventricular response, represented by the QRS complex. The segment between the P-wave and the R-wave represents the delay of the electrical circuit in the AV node. It represents the depolarization of both the right and left atria, which occurs at the same time. The P-wave is the first waveform in the complete waveform complex, and it's normally found upright in healthy patients.

(This will be discussed in more detail when we look at each individual rhythm.) Waveforms Explainedįor the following explanations, we'll be assuming that the waveform is normal, and that normal mechanical function is occurring. It simply shows that the electrical events that may stimulate myocardial function are happening. However, this doesn't mean that the heart muscle is reacting properly or in correlation with the electrical patterns. When assessing the electrical activity of a patient's heart, it's vital to recognize the underlying dysrhythmia and know how to treat it appropriately to restore a perfusing cardiac rhythm.Ī sinus rhythm is defined as any cardiac rhythm where depolarization of the cardiac muscle begins at the sinus node, which is characterized by the presence of correctly oriented P-waves on the electrocardiogram.Īn ECG waveform represents each electrical event in the cardiac conduction system during a cardiac cycle. Pro Tip #2: It's also important to remember that until an underlying cause has been identified and corrected, pharmacological and electrical therapies might offer little or no help when trying to resuscitate a cardiac arrest victim.

Acls heart rhythms