Atherosclerosis and Heart Disease

From the New England Journal of Medicine, April 1, 2004
Atherosclerosis is a big killer. No longer just the area of interest of cardiologists looking for a fixed narrowing in a coronary artery of a patient with angina, it is the target disease to beat for diabetologists, lipidologists, doctors specializing in the treatment of hypertension, and increasingly, neurologists. Yet many of these "ologists" attend meetings of specialist societies that focus either on individual risk factors for atherosclerosis or on clinical manifestations of the atherosclerotic process. So it is timely that books are beginning to reappear on the topic of atherosclerosis. (The word "reappear" is perhaps slightly misleading, since the former round of books on this topic tended to be written by pathologists, whereas now the interest is clinical, pathophysiological, and therapeutic.) For doctors, atherosclerosis presents problems that are not just clinical. Unlike other diseases that are essentially binomial -- we either have them or we don't -- atherosclerosis starts in childhood, and from early adulthood onward we all have it to some degree. This means that doctors have to think preventively. And once we start to think about prevention, we enter the field not only of epidemiology but also of public health and public policy. In Atherosclerosis and Heart Disease, Andrew Tonkin has pulled together an impressive group of experts from a wide range of areas of medicine with the aim of producing a clinical book on atherosclerosis. The topics range from preventive approaches to interventional ones, and some fit better than others. The overview of pathophysiology sets the scene and raises intriguing questions about the role of inflammation in atherosclerosis. This chapter also introduces another concept: it is not the size of an atherosclerotic lesion that determines the likelihood that it will promote thrombosis and thereby initiate a clinical event but, rather, its composition and its vulnerability to rupture. So although big lesions that are visible as discrete narrowings on angiograms may be the ones that limit blood flow and produce exertional angina, these are often not the lesions that cause heart attacks and death. These concepts may explain the puzzling speed with which lowering lipid levels, reducing blood pressure, and stopping smoking can help patients reduce their risk of cardiovascular events. Thus, although treating a patient with a statin drug for two years has little effect on atherosclerotic buildup, it dramatically reduces the rate of heart attack. Of course, this concept calls into question the common practice of dilating or bypassing a narrowing in an artery in order to reduce the risk of events, rather than simply to relieve symptoms. The book covers a wide range of topics and sets the scene in terms of clinical practice and a broad population approach to prevention. However, it does not always hit the mark. The chapters on diabetes, lipids, and blood pressure offer a practical guide to current treatment options for atherosclerosis and their effect on coronary artery disease but they do not really explore how the various treatments might affect arterial plaques. The discussion of novel risk factors is interesting, but it leaves the reader wondering which risk factors are likely to be important and whether any might be causal. I was also concerned that smoking is not accorded the prominence it deserves as quantitatively the most important risk factor for coronary artery disease in many patients. The book has some oddities. For example, although an arrhythmia can be a consequence of atherosclerotic disease, it seems to me that the condition does not really fit into a book about atherosclerosis but, rather, belongs in a textbook of cardiology. Tonkin seems to have intended the book to fill a gap in the literature, and to some extent, it succeeds. The book offers doctors in training in cardiovascular medicine a broad perspective on the disease process that affects the patients they see every day and outlines current therapeutic strategies. But is it an authoritative work on atherosclerosis that physicians will reach for in order to understand the disease or in times of clinical or scientific uncertainty? Unfortunately, I don't think so. It is, however, a step in the right direction. Patrick Vallance, M.D.
Copyright © 2004 Massachusetts Medical Society. All rights reserved. The New England Journal of Medicine is a registered trademark of the MMS.


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