Abstract: A blood flow assist system can include a blood pump and an elongate power lead having a distal end portion connected to the blood pump and a proximal end portion opposite the distal end portion. The power lead can include a lumen extending distally from the proximal end portion of the power lead along a longitudinal axis of the blood flow assist system and one or more electrical contacts disposed on an outer surface of the lead at the proximal end portion of the elongate power lead. The power lead can include a recess extending into the proximal portion of the power lead in a direction transverse to the longitudinal axis, the recess configured to receive a locking pin to releasable connect the power lead to an external device.