This book is for any individual who sees patients with implantable devices, or who will be taking an examination related to device management. Many caregivers working in the field of medicine find that one of the best ways to learn is by working through clinical cases, and for many people it's even more helpful to work through the examples as unknowns. This is especially true in the arena of implantable cardiac devices. In an effort to provide this experience, experts from the Mayo Clinic, Rochester, Minnesota, have produced three volumes of case studies that encompass variations of normal and abnormal function of pacemakers, ICDs, and CRT devices. The texts have been written collaboratively by six clinicians with differing backgrounds in an effort to present the cases in such a way that they are applicable to a variety of caregivers. Cases for this book were selected because of their clinical relevance and their usefulness for illustrating general principles, practical tips, or interesting findings in device practice, with the goal of advancing general concepts in device management.