A 48-year-old man had unusual sensations in his chest during exercise. His electrocardiogram is below, with lead aVF shown. What is the diagnosis?

Question

Quizplus · Accepted Answer

The electrocardiogram shows a premature ventricular contraction (PVC), indicated by the early QRS complex that is wider than normal and has a different morphology than the normal QRS complexes. The QRS complex originates in the inferior part of the ventricle, as evidenced by the negative deflection in lead aVF. Premature contractions originating in the atrium or high in the atrioventricular node would have a different morphology and would not have a negative deflection in lead aVF. Premature contractions originating low in the atrioventricular node or in the base of the ventricle would also have a different morphology.

A 48-Year-Old Man Had Unusual Sensations in His Chest During