It would be no exaggeration to state that medicine and surgery have progressed further in the last fifty years than in the preceding five thousand. One of the most revolutionary changes has been the rapid development and implementation of minimally invasive surgical techniques, which in specialty after specialty have supplanted long-accepted open surgical procedures. Interventional techniques, employing catheters, guidewires, stents and many miniaturized devices were first developed in the field of cardiovascular medicine and subsequently adapted to many other specialties. There is scarcely a medical or surgical situation today in which these minimally invasive techniques have not become a first line option, ranging from coronary artery disease to valvular heart disease, stroke, critical leg ischemia, hemorrhage, pulmonary embolism, tumor treatment, and various renal and hepatic conditions. The initial resistance encountered in many specialties has disappeared as each specialty has recognized the obvious advantages of these techniques and subsequently incorporated them into their own practices. There has also been a revolution in clinical training programs to incorporate training in these techniques and many specialties have moved closer together rather than competing, leading to rapid and dramatic advances in many fields. In this volume, we have been fortunate to have a group of internationally recognized authorities in many fields contributing chapters describing the use of interventional techniques in a wide range of urgent clinical situations. Originally these techniques were employed primarily in elective situations, but as their superiority became apparent, and the availability of expertise and sophisticated imaging technology became widespread, their use has now become the norm in emergent and urgent clinical settings. While the title of this book, Urgent Interventional Therapies, suggests that it refers primarily to acute situations, most of these techniques have widespread application in normal practice.