Pressure waveforms change with ventricular pacing

Pressure waveforms during pacing and sinus rhythm. Left panel: The rhythm initially is paced from the right ventricle and the right atrial (RA) pressure tracing demonstrates a significant "v" wave due to tricuspid regurgitation. Middle panel: In the presence of normal sinus rhythm in the last half of the tracing, the normal RA waveform is restored and the "v" wave is no longer seen. Right panel: The effect of the rhythm change on the pulmonary aretry (PA) pressure is depicted. During pacing, the PA pressure is higher and has a greater respiratory variation than during sinus rhythm.