NOS1AP and ventricular tachycardia: Whole‐cell patch‐clamp measurements of a conditional transgenic mouse model exhibiting cardiac‐specific Nos1ap over‐expression revealed a Nos1ap‐dependent increase of L‐type calcium channel nitrosylation, which led to increased susceptibility to ventricular tachycardias associated with a decrease in QT duration and shortening of APD90 duration.