Biology of Disease

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DISORDERS OF THE

CARDIOVASCULAR

SYSTEM

14.1 Introduction

The cardiovascular system comprises the heart, with its covering pericardium,
and blood vessels, that is, arteries, arterioles, capillaries, venules and veins,
which enclose and distribute blood to the tissues.

The heart is a muscular pump weighing about 500 g in an adult and is the
strongest muscle in the body. It can contract for over a hundred years nonstop,
beating about 100 000 times a day at a rate of about 70 beats min–1, to pump
blood (Chapter 13)) around the body. This supplies, for example, oxygen and
nutrients to the tissues and removes their waste products. However, in such a
complicated system many things can go wrong. In the developed countries,
heart disease is responsible for about half of the annual deaths. Much of
this is due to lifestyle, for example smoking, poor diets and excess weight. In
developing countries rheumatic heart disease is more of a problem but this
has decreased in the developed countries.

OBJECTIVES

After studying this chapter you should be able to:

N outline the structure of the heart and circulatory system;

N describe the general functioning of the heart;

N list the major types of heart diseases and their causes;

N review some of the methods for detecting and investigating heart disease;

N discuss the role of cholesterol and apolipoproteins in atherosclerosis;

N explain the use of antithrombolytic therapy;

N describe the major peripheral vascular diseases.