The QRS complex consists of the Q wave, the R wave and the S wave. The QRS complex comes after the P wave when the SA nodal action potential travels through the AV node to the ventricles to cause ...

The diagnosis is normal sinus rhythm, first-degree AV block (prolonged AV conduction), premature ventricular complexes, escape junctional complex, left ventricular hypertrophy with associated ST-T ...

The diagnosis is NSR, Mobitz type I second-degree atrioventricular (AV) block (Wenckebach), nonconducted (blocked) PACs, and early transition (counterclockwise rotation). The rhythm is irregular, but ...

A 90 year old male with no past medical history to clinic with a complaint of generalized weakness, dizziness, and dyspnea on exertion. Mild lower extremity edema, paroxysmal nocturnal dyspnea, and ...

There is clearly a tachycardia with narrow QRS complexes indicating a supraventricular rhythm. The clues to the aetiology are the heart rate of almost exactly 150 / min and the saw tooth waves seen ...