The development of modern programmable pacemaker-systems has led to a series of questions which until now have apparently not existed in the treatment of cardiac rhythm disturbances. These questions touch especially on the problem of whether the relation which usually exists between a diagnostic step and its therapeutic consequence, namely its therapeutic relevance, is abolished or at least changed.

The main topic of this article is Otto Frank's forgotten notion of the pressure-volume diagram of the cardiac ventricle as a means to assess the external mechanical work of the heart. Developed by Frank at the end of the 19th century, this idea was reenvisioned as pressure-volume area about 70 to 80 years later by Hiroyuki Suga. This notion now serves as a perspective for defining cardiac contractility and thus enabling the controlled clinical application of cardiac assist devices. We begin (...) our discussion, however, with the work of Ernest H. Starling, whose dominant influence on the thinking of cardio-physiologists led to a neglect of some of the fundamental insights of Frank's... (shrink)

Coronary by-pass surgery has been performed in hundreds of thousands of patients in the last 15 years with a high standard of technical and surgical perfection. The indications for this kind of surgery, however, are still controversial because in spite of many retrospective and several prospective studies it cannot be proven convincingly that in a given patient this surgical procedure will prolong life or prevent myocardial infarction. The present attempt to analyze the causes for this controversy shows that the main (...) reasons for this uncertainty lie: (a) in the enigma of the underlying (ischemic heart) disease itself, which is supposed to lend itself to surgical therapy; (b) in the inadequate methods available up until now for characterizing the state of the disease, its probable course, and its pathogenesis; and (c) in the professional group interests which have a momentum of their own. (shrink)

Coronary by-pass surgery has been performed in hundreds of thousands of patients in the last 15 years with a high standard of technical and surgical perfection. The indications for this kind of surgery, however, are still controversial because in spite of many retrospective and several prospective studies it cannot be proven convincingly that in a given patient this surgical procedure will prolong life or prevent myocardial infarction. The present attempt to analyze the causes for this controversy shows that the main (...) reasons for this uncertainty lie: (a) in the enigma of the underlying (ischemic heart) disease itself, which is supposed to lend itself to surgical therapy; (b) in the inadequate methods available up until now for characterizing the state of the disease, its probable course, and its pathogenesis; and (c) in the professional group interests which have a momentum of their own. (shrink)