Heart failure is a complex syndrome resulting from cardiac
disorders that impair the ventricles’ ability to fill with and effectively pump blood (Hunt
... [Show More] et al., 2005). In heart failure, the
heart is unable to pump enough blood to meet the metabolic demands of the body. It is the end result of many conditions. Frequently, it is a long-term effect of coronary heart disease
(CHD) and myocardial infarction (MI) when left ventricular
damage is extensive enough to impair cardiac output (see
Chapter 31 ). Other diseases of the heart also may cause
heart failure, including structural and inflammatory disorders.
In normal hearts, failure can result from excessive demands
placed on the heart. Heart failure may be acute or chronic.
THE CLIENT WITH HEART FAILURE
As mentioned, heart failure develops when the heart cannot effectively fill or contract with adequate strength to function as a
pump to meet the needs of the body. As a result, cardiac output
falls, leading to decreased tissue perfusion. The body initially
adjusts to reduced cardiac output by activating inherent compensatory mechanisms to restore tissue perfusion. These normal mechanisms may result in vascular congestion—hence, the
commonly used term congestive heart failure (CHF). As these
mechanisms are exhausted, heart failure ensues, with increased
morbidity and mortality.
Heart failure is a disorder of cardiac function. It frequently is
due to impaired myocardial contraction, which may result from
CHD and myocardial ischemia or infarct or from a primary cardiac muscle disorder such as cardiomyopathy or myocarditis.
Structural cardiac disorders, such as valve disorders or congenital
heart defects, and hypertension also can lead to heart failure when
the heart muscle is damaged by the long-standing excessive workload associated with these conditions. Other clients without a primary abnormality of myocardial function may present with
manifestations of heart failure due to acute excess demands
placed on the myocardium, such as volume overload, hyperthyroidism, and massive pulmonary embolus (Table 32–1). Hypertension and coronary heart disease are the leading causes of heart
failure in the United States. The high prevalence of hypertension
in African Americans contributes significantly to their risk for and
incidence of heart failure.
Incidence, Prevalence, and Risk Factors
Nearly 5 million people in the United States are currently living with heart failure; approximately 550,000 new cases of
heart failure are diagnosed annually (American Heart AssociaTABLE 32–1 Selected Causes of Heart Failure
IMPAIRED MYOCARDIAL FUNCTION INCREASED CARDIAC WORKLOAD ACUTE NONCARDIAC CONDITIONS
■ Coronary heart disease ■ Hypertension ■ Volume overload
■ Cardiomyopathies ■ Valve disorders ■ Hyperthyroidism
■ Rheumatic fever ■ Anemias ■ Fever, infection
■ Infective endocarditis ■ Congen [Show Less]