Since the introduction of balloon angioplasty for the relief of coronary artery stenoses and of anginal symptoms in patients with coronary artery disease by Andreas Griintzig in 1977, the field of interventional technology and treatment strategies has grown enormously. For the reduction of hemodynamically significant coronary artery stenoses balloon angioplasty is the standard and reference method with a high primary success and low complication rate. Because of the relatively high recurrence rates of 30-40% of balloon angioplasty a whole family of different angioplasty techniques has been developed since then. Among those are atherectomy devices, laser angioplasty, radiofrequency angioplasty, high and low speed rotational angioplasty and stenting of stenosed vessels. Balloon angioplasty has been extended to aortic and mitral valve stenoses, and supraventricular and ventricular tachycardias can now be treated by catherter ablation techniques. In 1989 an International Symposium on standard and newer inter- ventional techniques has been held at the University of Ulm. This volume contains the essential parts and presentations of the international faculty of experts in the field. In four chapters the principles, advantages, pitfalls and future developments of coronary angiopiasty, angioplasty of peripheral arteries, balloon valvuloplasty and of catheter ablation of supraventricular and ventricular tachycardias are described in detail. We hope that this ‘State-of-the-Art’ representation will be of great value for both the non- expert reader and the active researcher in the fields addressed within the book. V. Hombach, M. Kochs and A. J. Camm ix List of contributors U. U.