Coronary Artery Disease
Objectives Briefly outline the pathophysiology of CAD, and list the risk factors. Describe the diagnostic tests.
Health Data Concepts Epidemiology Study of disease events in a population Incidence The number of new cases of a disease in a specified population over
a defined period Prevalence The number of all cases of a disease or occurrences of a disease
during a particular period
Health Data Concepts (con’t) Determinants of Health Income & Poverty Employment Education Housing Culture & Ethnicity Social Cohesion & Social Support
CORONARY HEART DISEASE
CHD is a major cause of mortality and morbidity.
Cancer is now the major cause of death , but CHD is the single most important cause of death in adults (Pomare et al 1995).
RISK FACTORS AGE GENDER FAMILY HISTORY DIABETES HYPERTENSION TOBACCO USE SEDENTARY LIFESTYLE DIET HOW ONE MANAGES STRESS
Major Causes of Death 1999
Coronary Artery Disease Obstructed blood flow through the coronary arteries. Plaque Accumulation -> Atherosclerosis Coronary vasospasm Leading cause of death in the industrialised Western world
PATHOPHYSIOLOGY CAD refers to the development and progression of plaque accumulation in the coronary arteries.
It is a continuum: Stable angina Unstable angina MI.
Cholesterol
Pathophysiology of CAD
Atherosclerosis
Atherosclerosis, the most common form of arteriosclerosis, an arterial disease consisting of proliferation of internal smooth muscle cells, accumulation of macrophages and lymphocytes, formation of connective tissue and deposition of lipids in the vessel wall.
Atherosclerotic plaques are variable in composition consisting of predominantly fibrous tissue and smooth muscle in some and of lipid and necrotic material in others.
Atherosclerosis is the cause of the vast majority of cases of obstructive arterial disease and in the form of coronary arterial obstructive disease
the number one cause of morbidity and mortality in the Americas and Europe.
Arterial occlusion is usually a consequence of plaque rupture with release of thrombogenic lipids, platelet accumulation and eventually thrombosis.
X-ray angiography and magnetic resonance angiography MRA demonstrate atherosclerotic plaques projecting into the lumen and narrowing of the lumen.
Depiction and characterization of the arterial wall and plaque itself has been done with intravascular ultrasonography in recent years. The feasibility of employing intravascular MRI for characterization of plaques has been recently shown.
Systemic effects
Severe carotid stenosis of the internal carotid artery just beyond the division of the common carotid artery into the internal and external branches.
STABLE ANGINA
Oxygen and nutrient supply. Role of risk factors. Lactic acid ischaemic pain. Known threshold. Angina that occurs with predictable level of exertion.
Acute Coronary Syndrome (Unstable Angina -> MI)
Angina not necessarily associated with activity. ECG: ST depression
CLINICAL MANIFESTATIONS
Chest pain or anginal equivalent (jaw pain, left arm pain) Nonverbal indicators of pain or in heart rate or in blood pressure Dysrythmias
DIAGNOSTIC TESTS
Electrocardiograph Blood tests Stress testing Cardiac catheterization
STRESS TESTING An exercise stress test demonstrates the significance of coronary artery blockages relative to the patient’s functional status.
This non-invasive test indicates areas of the myocardium that do not receive adequate perfusion at peak exercise.
CARDIAC CATHETERIZATION
Invasive technique used to assess coronary anatomy, ventricular function, and haemodynamic status.
Angiography
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