My friend has a defibrillator on one side and a pacemaker on the other. Why do I have just a defibrillator? FAQ » Treatment » Implantable Devices » My friend has a defibrillator on one side and a pacemaker on the other. Why do I have just a defibrillator? Tags: ICD Most ICDs today have both pacing therapies as well as defibrillation capabilities, so only one device is needed.