An implantable cardioverter defibrillator will give the patient extra beats in a programmed sequence to terminate a fast heartbeat. If that fails and the rhythm could be dangerous it will deliver a shock. It also functions as a basic pacemaker to deal with slow rhythms.
The implantation procedure is similar to that described above for a pacemaker.
The patient can go home the next day. The DVLA will require a period off driving the length of which depends on the clinical circumstances.