THE CONDUCTION SYSTEM OF THE HEART: STRUCTURE, FUNCTION, AND CLINICAL IMPLICATIONS

THE BOOKSHELF THE CONDUCfiON SYSTEM OF THE HEART: STRUCTURE, FUNCTION, AND CLINICAL IMPLICATIONS. Edited by H. J. J. WELLENs, K. I. LIE, and M. J. JANSE. Philadelphia, Lea and Febiger, 1976, 708 pp, $58.00. A useful symposium has the capacity to shift or enlarge our image of an advancing science. Component parts may be of uneven texture, but the scope enriches our understanding of complex phenomena. The Conduction System of the Heart: Structure, Function, and Clinical Implications, edited by Wellens and associates, contains 37 items relating to the anatomy and electrophysiology of the heart. Handsome in price, the monograph is equally handsome in its contents. Initial reports detail the embryologic development of the cardiac conducting system. Controversy surrounding the interconnection between the sinoatrial and atrioventricular nodes is discussed by Truex, who opts in favor of atrial muscular fiber bundles, rather than special neuromuscular pathways. Beautiful and clearly labeled diagrams and photomicrographs amplify these portions of the text. A subsequent chapter reviews slow-channel (calcium-current) physiology and its likely presence in ischemia, digitalis intoxication, and normal sinoatrial and atrioventricular nodal function. Two masters of deductive logic, Rosenbaum and Pick, review various examples of phase 3 and 4 conduction block and, in particular, parasystole. Several chapters discuss the uses of extrastimulus and His bundle recordings to pinpoint the origins of defects in conduction and tachyarrhythmias not discernible from the surface electrocardiogram. As is too often true in the medical literature, accepting the presence of His bundle depolarizations in many of the figures requires an act of faith. Work from Damato's laboratory, where His spikes are easily seen, is a distinct exception. In the discussion of the gap phenomenon in atrioventricular conduction, explicable in terms of initial distal and subsequent proximal delays in conduction, the figures clarify and supplement the text. The use of His bundle electrography and extrastimulus techniques to expose anomalous pathways of atrioventricular conduction and the origins of reentrant tachycardias is · discussed in several reports. The advantages and shortcomings of these laboratory methods are critically examined. This volume will serve cardiologists and all physicians with a special interest in cardiac dysrhythmias.

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The bibliography has been conveniently alphabetized at the end of the book, rather than at the end of each chapter, and contains more than 900 references. Michael D. Klein, M.D., F.C.C.P. Boston

FUNDAMENTALS OF RADIOLOGY (2nd ed). By LuCY FRANK SQUIRE. Cambridge, Mass, Harvard University Press, 1975, 366 pp, $17.00. The first edition of this text in 1961, which carried the title, Fundamentals of Roentgenology, suited to perfection both the requirements of the teacher and that of the student in the art of radiographic diagnosis. The new edition, renamed Fundamentals of Radiology, shows few alterations to the text but preserves the high level of pedagogy shown in the first edition without significant alteration. The text is comprehensible to all medical students and will arouse in their own minds a desire to find out how any x-ray film can be analyzed to bring out a diagnosis important to the patient. This plan for analysis will extend beyond the student years and will serve equally well when the student becomes a practicing physician. At the request of her colleagues, a case index has been added by Dr. Squire, with reluctance; however, for the teacher, it allows him to bring to the teaching session additional, but not repetitive, radiographic cases from the teacher's personal teaching collection. The section on gastrointestinal herniations has been greatly shortened to allow space for a crisp exposition of the hazards of radiation. Recent developments in contrast studies of the kidney, liver, and biliary tree have warranted complete revision of the text. A few new cases have been added, and some illustrations have been enlarged for better detail. Why have so few changes been made? How very few medical textbooks survive 16 years without drastic revision! Based on the text of the first edition and the overwhelming response of medical students and radiologists to it, the book has become a veritable vade mecum or even a bible for both student and teacher. Its printed page is a restatement of a fundamentally oral transfer from teacher to student of a method of analysis and deduction from facts for a single diagnosis, or a group of possibilities, fitting the patient's complaints and physical signs of disease. The method is the essence, yes, the quintessence of that used by all radiologists in making their own diagnoses. The book might well have suffered from overzealous correction and have lost its lucidity. Squire is to be commended on her conservatism.