A 2:1 atrioventricular block presenting paradoxical ventriculophasic response.

Ventriculophasic response (VR) is defined as the shortening of the sinus cycle length in the setting of greater than second-degree atrioventricular (AV) block. Typically, the PP intervals interposing a QRS complex are shorter than those without a QRS complex. Paradoxical VR is a rare clinical entity. We report about an 80-year-old man presenting with a 2:1 AV block, in whom typical and paradoxical VRs were observed.