Page 238 - ACCCN's Critical Care Nursing

Cardiovascular Alterations

and Management 10

Robyn Gallagher
Andrea Driscoll

Learning objectives Key words

After reading this chapter, you should be able to: arrhythmia
● explain the pathophysiology of coronary artery disease, acute coronary syndrome
clinical manifestations of acute coronary syndromes and myocardial infarction
management of events percutaneous coronary intervention
● discuss the collaborative care for a patient with chest pain acute heart failure
● list the diagnostic tests used to assess myocardial ischaemia left ventricular failure
● outline the actions and contraindications of thrombolytic right ventricular failure
drugs aortic aneurysm
● outline the clinical manifestations of right and left endocarditis
ventricular failure cardiomyopathy
● discuss the goals of heart failure treatment hypertensive emergencies
● discuss the pathophysiology of the four different types of ventricular aneurysm
cardiomyopathy and how it affects cardiac function
● outline the actions of angiotensin converting enzyme
inhibitors, beta-blockers, loop diuretics and spironolactone
and how they relate to the pathophysiology of heart failure CORONARY HEART DISEASE

Coronary heart disease (CHD) is the term used to describe
the effects of a reduction or complete obstruction of
blood flow through the coronary arteries due to narrow-
INTRODUCTION ing from atherosclerosis and/or thrombus. Although
some patients may be asymptomatic, the commonest
This chapter reviews the support of cardiovascular func- manifestations of CHD are chest pain due to angina,
tion in the face of many compromises to the system. It acute coronary syndrome (ACS, a term used to collec-
focuses on two of the most prevalent and fatal diseases tively describe acute myocardial infarction [AMI] and
affecting the heart: coronary heart disease and heart unstable angina) and sudden death. CHD may also cause
failure. These diseases are also a common co-morbidity arrhythmias and heart failure. 1
in elderly patients admitted to critical care units. The first
section on coronary heart disease reviews the pathophysio- CHD is the leading cause of death, premature death and
2,3
logical concepts of myocardial ischaemia and associated disability in Australia and New Zealand. In 2007, more
complications, with detailed consideration of the clinical than 22,000 people died of CHD in Australia, more than
2-4
implications, assessment and associated management. 5000 in New Zealand in 2004 and 7.2 million worldwide.
Heart failure is discussed in terms of the body’s compen- Death rates have fallen by about 76% since the 1960s,
satory mechanisms and the clinical sequelae and associ- primarily due to improvements in risk factors and health
ated clinical features of heart failure. Nursing and medical care for those at risk. However, the burden of CHD
management is outlined including the management of remains high, with 1.5% of Australians reporting CHD
2
acute exacerbations of heart failure. Finally, other cardio- symptoms. Furthermore, CHD is the single leading
vascular disorders commonly managed in critical care health problem worldwide because of a rising incidence
4
units are reviewed ranging from other forms of heart in developing countries.
failure to hypertensive emergencies and aortic aneurysms.
The case study presented at the end of the chapter high- MYOCARDIAL ISCHAEMIA
lights the key aspects of the management of coronary When coronary blood flow is insufficient to meet myo-
heart disease and heart failure in patients admitted to cardial tissue demand for oxygen, myocardial ischaemia
critical care units. occurs. Critical restriction to blood flow occurs when the 215