A transient voltage/surge current protection system is provided for electronic circuits associated with implanted leads. In particular, a transient voltage suppressor such as a diode, a zener diode, a transorb, a surge protector, varistor components or the like, is placed in parallel with the electronic circuits to thereby divert harmful surge current and bypass the electronic circuit during an external defibrillation event or during an applied therapeutic shock, such as from an ICD.