Normal and Abnormal Conduction in the Heart [antikvár]

PrefaceTwenty years have gone by since the international meeting on "The Specialized Tissues of the Heart" convened in Rio de Janeiro, under the sponsorship of the Instituto de Biofisica. Cardiac microelectrophysiology was then only ten years old. We knew then much of what we know today about the varied contour of cardiac action potentials. We had learned of the ionic mechanism of the fast upstroke in Purkinje fibers, of the importance of potassium conductance changes during plateau and pacemaker potentials, and of the ionic mechanism of cholinergic inhibition in nodal and atrial tissues. On the other hand, we had no inkling of the existence of slow responses as a separate excitable entity, and, of course, we knew nothing about the role of calcium in its genesis. The mode of action of catecholamines was a mystery; and cell junctions were mostly considered as permanent, low resistance connections in health and disease, except for the "healing-over" of gross lesions of the cardiac tissue. With so much knowledge left out, we understood arrhythmias only in the crudest terms, and our explanations were based on the standard parameters of nerve excitability applied to the three-dimensional latticework of heart muscle.Progress has been remarkable in these twenty years, both quantitatively and qualitatively. Classical electrophysiology of adult and cultured heart cells and the technicjue of voltage clamp have revealed a rich collection of unsuspected phenomena. Ultrastructure research has progressed to the point where it can add significant data to clarify the finer biophysical and physiological arguments. Other biophysical methods are now emerging as potential sources of useful information. The Organizing Committee was therefore eager to call a new meeting, involving many of the colleagues from the Americas and Europe who have contributed most to the field. Our only regret is that we could not bring all of them together. The Instituto de Biofisica of the Universidade Federal do Rio de Janeiro, together with the Academia Brasileira de Ciencias, agreed to sponsor this revival of their early I960 enterprise. Thanks to them, this book collects the beautiful work of many laboratories and the best piece of mind of our guests during the lively discussions. We feel the volume is a most appropriate and critical representation of the present state of basic electrophysiological knowledge of both normal and abnormal excitation of the heart.A.P.C.M.L.B.F.H.