There are many excellent textbooks that exist in the area of implantable devices for arrhythmia control. Few textbooks, however, provide a case study approach. Collectively, these workbooks provide an approach to problem solving an electrocardiographic interpretation for patients with permanent pacemakers and defibrillators. Volume 1 addresses patients with permanent pacemakers Volume 2 examines interactions between pacemakers and implantable defibrillators Volume 3 provides case studies of transtelephonic pacemakers electrocardiography Volume 4 provides more pacemaker and implantable defibrillator troubleshooting cases This volume takes a case-orientated approach, providing a diverse series of problems on a broad range of topics related to implantable defibrillators. The cases are divided into easy, moderate and complex according to their level of difficulty, allowing the reader to gauge their progress. This workbook is suitable for physicians, nurses, technicians, technologists and industry engineers, particularly those new to the field who are keen to learn in a practical way.