Clinical Cardiology: Current Practice Guidelines
Clinical Cardiology: Current Practice Guidelines, edited by Demosthenes G. Katritsis, Bernard J. Gersh, and A. John Camm and published by Oxford University Press, confronts the reader with a novel phenotype of cardiology textbook. In a classic textbook, each chapter provides the reader with a structured description of the subject, starting from pathophysiology and ending with clinical management. In Clinical Cardiology, each chapter consists of a succinct description of the subject, which should enable the reader to understand a subsequent set of diagnostic and management guidelines recently provided on the subject by American or European cardiologic professional societies. This novel concept of a cardiology textbook leaves an ambivalent impression, which is already evident from title and subtitle: The title Clinical Cardiology announces a classic textbook, but the subtitle Current Practice Guidelines suggests a compilation of diagnostic criteria and management recommendations issued by professional societies. This compilation has been described in the foreword as a tool kit for cardiologists. Providing cardiologists with a tool kit suggests modern clinical practice to resemble the assembly of IKEA furniture, which requires strict adherence to the manual to avoid collapse of the wooden commode. Daily clinical practice, however, remains a one-on-one interaction between a caring physician and an individual patient. Most patients do not fit perfectly into recommendations of professional societies or outcomes of large multicenter trials; therefore, their management continues to require a thorough understanding of cardiac pathophysiology. In this respect, it remains doubtful whether the limited information provided by Clinical Cardiology will suffice for the correct use of professional guidelines in individual patient management.
Clinical Cardiology consists of 22 parts and 85 chapters. The subdivisions between parts and chapters seem to have been made in an arbitrary fashion. Grown-up congenital heart disease, valve disease, and coronary artery disease each constitute a single part, similar to genetic channelopathies, implantable devices, rheumatic fever, and infective endocarditis. This arbitrary use of parts and chapters detracts from the user-friendliness of the book. Rheumatic fever and infective endocarditis were better categorized as chapters of valve disease, not as individual parts, and all of the arrhythmic parts should have been chapters in a single focused cardiac rhythm part.
The part on congenital heart disease focuses on grown-up congenital heart disease. This is laudable because adult patients with corrected or partially corrected congenital heart disease constitute an ever-growing and challenging part of daily clinical practice. A disappointing feature is the almost complete absence of echocardiographic images despite echocardiography being the cornerstone of modern diagnosis of congenital heart disease. The only echocardiographic image shown is a blurred picture of Ebstein anomaly in which the insertion of the tricuspid valve is hardly visible. A similar lack of echocardiographic illustrations is also present in the part on valvular heart disease. Furthermore, murmurs are described in the text rather than visually displayed in phonocardiograms.
For both the congenital and valve disease parts, it remains uncertain whether the introductory information to each chapter will allow the reader to correctly use the subsequent guideline figures and tables provided by the professional societies. This is nicely illustrated by the American College of Cardiology/American Heart Association flow chart on the management of mitral stenosis, which explicitly asks for an assessment of valve morphology to judge suitability for balloon valvuloplasty. Echocardiographic images of mitral valves suitable or unsuitable for balloon valvuloplasty, however, are missing, although this information is a prerequisite for correct application of the American College of Cardiology/American Heart Association recommendations for the treatment of mitral stenosis. The part on valve disease also painfully illustrates that many management decisions are supported by only Class IIa, Level of Evidence B or C even for common conditions such as asymptomatic aortic or mitral regurgitation with preserved left ventricular function. The limited support from guidelines of professional societies for these common clinical conditions shows that pathophysiological insight into volume-overload cardiomyopathy remains indispensable for judicious patient management. A modern clinical textbook of cardiology should continue to provide this information.
In contrast to biblical texts, recommendations and guidelines of professional societies are short-lived and fallible. Both of these features also impinge on Clinical Cardiology. To accommodate the latest version of guidelines, the authors committed themselves to update the online version of the textbook biannually. The purchase of the textbook, however, only covers 12 months’ access to the online version. This implies a renewed purchase of the textbook every 24 months to avoid reliance on outdated guidelines. Furthermore, guidelines are issued by multiple professional societies and sometimes appear at a rapid rate, as illustrated by the guidelines on heart failure. In 2012, new European Society of Cardiology guidelines for the diagnosis and treatment of acute and chronic heart failure were released. In 2013, another set of guidelines for the management of heart failure was published by the American College of Cardiology Foundation/American Heart Association. In Clinical Cardiology, the medical treatment recommendations for symptomatic systolic heart failure of both the 2012 and 2013 sets of guidelines appear side by side in 2 distinct figures. The flow charts depicted in both figures are strikingly different and leave every guideline-obeying reader confused: Addition of ivabradine and digoxin shows up only in the figure representing the 2012 European Society of Cardiology guidelines, and addition of the combination hydralazine–nitrates is restricted to blacks in the figure representing the 2013 American College of Cardiology Foundation/American Heart Association guidelines. An unambiguous integration of new guidelines into Clinical Cardiology will require more than a simple juxtaposition of figures and tables and will force the editors to make omissions and additions based on their clinical judgment. Apart from being short-lived, guidelines of professional societies can also contain flaws, and in order not to amplify these flaws, a textbook that reproduces these guidelines should critically assess them. In the heart failure part of Clinical Cardiology, the figure showing the diagnostic flowchart for suspected heart failure was copied from the 2012 European Society of Cardiology guidelines. A general consensus exists that the flowchart displayed in this figure is unsatisfactory for heart failure with preserved ejection fraction because it relegates the diagnosis of heart failure with preserved ejection fraction to a mere footnote. By simply copying this figure, Clinical Cardiology provides the reader little support on how to diagnose heart failure with preserved ejection fraction despite that fact that this heart failure phenotype currently accounts for >50% of prevailing heart failure.
In Clinical Cardiology, all the chapters were written by the 3 editors. A cardiology textbook written by as few as 3 authors constitutes a remarkable achievement. Because of the limited authorship, redundancies are prevented, and the content of the different chapters is in close agreement with each other. The editors of Clinical Cardiology ventured into uncharted territory, namely the no man’s land between a classic cardiology textbook and a compilation of guidelines issued by professional societies. As with every new endeavor, Clinical Cardiology presents with shortcomings: The introductory information of some chapters is too limited to enable the reader to judiciously apply subsequent diagnostic or management guidelines, and the guidelines themselves need a critical assessment, especially when competing sets of recommendations exist. These shortcomings notwithstanding, Clinical Cardiology presents a novel adjunct for every cardiologist who wishes to integrate evidence-based medicine into his or her daily practice.
Walter J. Paulus, MD, PhD
Institute for Cardiovascular Research
VU University Medical Center
Amsterdam, The Netherlands
- © 2014 American Heart Association, Inc.