Minimizing right ventricular pacing in sinus node disease: Sometimes the cure is worse than the disease

Figure 1 ECG after implant showing atrial-based pacing with spontaneous ventricular activation. AP-VS interval: 280-300 msec. Right atrial stimulus artifact is followed by a first deflection corresponding to right atrial depolarization (blue arrow) and then a second corresponding to left atrial depolarization (black arrow). AP: Atrial pacing; VS: Ventricular sensing.

Figure 2 Pulsed wave mitral Doppler recording. A: Pulsed wave mitral Doppler recording during an episode of symptomatic orthostatic hypotension with atrial-based pacing: E/A wave fusion with a particularly short diastolic filling time (280 msec at 80 beats per minute); B: Diastolic filling after AV delay optimization at 90 msec (“forcing” RV pacing): Good separation of E and A waves at pulsed wave mitral Doppler (filling time 547 msec at 70 beats per minute).