Anodal stimulation

Unintentional capture at the anode

Can still have cathode capture simultaneously, or anodal only capture if programmed subthreshold.

More likely to have anodal capture when

•Pacing at higher output

•the anodal is a small electrode, or smaller than the cathode.

•Basically impossible to have anodal capture when LV lead is programmed LV tip–RV coil (coil too large) (0% incidence)

•More likely to have anodal capture when LV lead is programmed to another LV pole (LV2-LV3) or LV1-RV ring (74% incidence)

Can be an issue when unintentional capture is occurring for example on RV ring, in particularly when the desired VV interval is LV-RV 40ms.

•In actual fact this would be LV-RV simultaneous

Studies have shown 20% of pts with anodal stim have decreased EF