What causes the P-Waves to be missing on a 4 lead ECG?
I hope I can clarify a misunderstanding that you may or may not have. One CANNOT interpret an ECG as “sinus” without the presence of p waves. To put it another way, when an ECG is interpreted as normal sinus rhythm, what is being implied? The implication is that the origin of cardiac conduction is occurring at the sinus node. To follow — the presence of a p wave reflects activation of the sinus node. In fact, one can have a normal sinus rhythm without ANY QRS activity! If one sees p waves in a regular fashion without any QRS activity, the ECG may be interpreted as “normal sinus rhythm” with complete heart block and without any junctional or ventricular escape. The meaning here is that the sinus node is firing normally; however, due to disease of the AV node and the rest of the cardiac conduction system, electrical activation cannot proceed beyond the atria. It could be that the patient’s own sinus node is working fine, and the ECG failed to properly record due to various reasons; howe
