The main subject of this book is the investigation of cardiac function and in particular ventricular function with radionuclide-based techniques. Emphasis is given to the study of clinical cases which can routinely occur in the life of a busy cardiological practice, by comparing conventional techniques, such as the electrocardiogram, the echocardiogram or the catheter study, with the newer nuclear medicine imaging procedures. Four basic images are given (end systole, end diastole, amplitude and phase), obtained either with a first pass or an equilibrium methodology, and the information analyzed. The clinical material is not exhaustive but covers a broad spectrum, with examples of coronary artery disease, valvular disease, cardiomyopathy, conduction disease and congenital heart disease. The book is aimed not only at the practising specialist (cardiologist, radiologist, nuclear medicine physician) but also at the general physician and surgeon interested in finding out what modern non invasive nuclear medicine procedures have to offer in the investigation of the heart. London, June 1982 ACKNOWLEDGEMENTS We are specially grateful to the Sir Jules Thorn Charitable Trust for its continuous support and interest.