Although, in the light of the beneficial effects of MPO inhibition, it seems reasonable to speculate that inhibition of other neutrophilic proteins such as PAD4 has similar antiarrhythmic effects in the MI setting, as it reduces inflammation and infarct size, both parameters known to directly correlate with arrhythmia burden in patients (244, 245). Here, PADI4 is linked to myocardial infarction.