●Introduction 211
●Pathophysiology and implications for treatment 211
●Therapeutic objectives and general measures for
chronic heart failure 213●Drugs for heart failure 213CHAPTER 31
HEART FAILURE
INTRODUCTION
Heart failure occurs when the heart fails to deliver adequate
amounts of oxygenated blood to the tissues during exercise or,
in severe cases, at rest. Such failure of the pump function may
be chronic, in which case symptoms of fatigue, ankle swelling,
effort dyspnoea and orthopnoea predominate, or it may be
acute, with sudden onset of shortness of breath due to pul-
monary oedema (Figure 31.1). Both acute and chronic heart
failure severely reduce life expectancy (Figure 31.2). The most
severe form of heart failure (low cardiac output circulatory
failure, ‘cardiogenic shock’) is managed with pressor drugs
(e.g.adrenaline) or with mechanical support (e.g. intra-aortic
balloon pump), in an intensive care unit. Such treatment is
highly individualized (and specialized) and mortality even
with the best treatment is very high. In this chapter, we cover
the more common syndrome of chronic congestive heart fail-
ure and discuss the treatment of acute pulmonary oedema,
since this is a common emergency.
PATHOPHYSIOLOGY AND IMPLICATIONS
FOR TREATMENTHeart failure is an end result of many diseases (not only of the
myocardium, pericardium and valves, but also of extracardiac
disorders, including systemic or pulmonary hypertension,
fluid overload, vascular shunts, anaemia and thyrotoxicosis).
The most common of these are ischaemic heart disease
(Chapter 29), idiopathic congestive cardiomyopathy and
cor pulmonale (Chapter 33). Specific measures are needed in
each case and these are covered in other chapters. Here,(a) (b)Figure 31.1:Peripheral oedema with evidence of pitting (left) and pulmonary oedema on chest x-ray (right), both important
consequences of uncontrolled and inadequately treated heart failure.