In patients with Tetralogy of Fallot and an indication for primary prevention ICD (NSVT, induced VT during EPS, or Low LVEF), should pulmonary valve interventions be offered PRIOR to ICD to assess if improvement in VT burden/EF?

There is a lot to consider for this question.

First, appropriate indications for primary prevention ICD in tetralogy of Fallot are not at all clear. While arrhythmias and left ventricular dysfunction are clearly risk factors for malignant arrhythmias, that is very different from saying that individuals with those risk factors will benefit from a primary prevention ICD. For these patients, discussion with a congenital electrophysiologist is still needed to determine whether ablation without ICD would be appropriate vs. ICD +/- ablation.

Second, if there is an indication for pulmonary valve replacement, I would absolutely offer that, particularly given the Bokma et al. INDICATOR study showing improvement in the composite outcome of death or sustained VT post-PVR. However, it is important to keep in mind that in their analysis, in those who did not meet their defined criteria for PVR (some of whom had PVR regardless), there was no association between PVR and the primary outcome (death or sustained VT). At this time, there is no data to support performing PVR in an effort to improve VT burden/EF if there are no indications for PVR otherwise.