Can you use an aed with a metal heart valve?

Yes. After first calling an ambulance, apply the suction pads and leads as directed. This allows the AED to monitor and record the heart action, and direct further if a shock is required. A shock will ONLY be delivered if the heart is in fibrilllation. If there is no pulse, CPR should be started until help arrives, regardless of if the AED tells you 'no shock required', this is because, as mentioned before, the AED is only effective in fibrillation.