Sudden death
- may be the presenting clinical manifestation of coronary atherosclerosis,
but is more likely to occur in patients with prior myocardial
infarction and moderate-to-severe left ventricular dysfunction
- approximately 20% of patients with acute myocardial infarction
die before reaching a hospital (unattended death)
- ventricular fibrillation is responsible for most cases of
sudden death
Angina pectoris
- angina pectoris is a clinical condition characterised by precordial
chest pain, usually precipitated by exertion or stressful conditions
and rapidly relieved by rest or nitrate administration
- the diagnosis is established on the basis of electrocardiographic
or scintigraphic evidence of ischaemia during pain. When angiography
is performed for the sake of diagnosis, evidence is usually
provided of significant obstruction of major coronary vessels
- angina is generally caused by the presence of atherosclerotic
lesions, producing flow-reducing stenoses
- coronary vasospasm may be associated with arterial lesions
or, less frequently, may occur in apparently normal vessels
- angina may be part of the clinical picture of severe myocardial
hypertrophy, severe aortic stenosis or insufficiency, hyperthyroidism,
pronounced anaemia or paroxysmal tachycardias, even in the absence
of haemodynamically significant coronary stenosis
Unstable angina
- the term 'unstable angina' refers to a condition of clinical
deterioration of a pain pattern in patients with previously
stable angina
- new-onset angina is also considered unstable
- coronary evaluation of patients with unstable angina demonstrates
in most cases the occurrence of complex coronary stenoses, suggesting
plaque rupture and thrombosis [Fuster,
1999]
- this unstable condition may progress to complete occlusion
and acute myocardial infarction, or might improve and evolve
towards a pattern of stable, although possibly more severe,
angina
Acute myocardial infarction
- acute myocardial infarction is characterised by sudden and
prolonged anterior or occasionally posterior chest discomfort,
often in association with arrhythmia, hypotension, shock or
cardiac failure
- typical electrocardiographic abnormalities and/or elevation
of cardiac enzymes confirm the clinical diagnosis. At echocardiography,
segmental wall motion abnormalities are usually detectable
- in most instances, this severe condition is produced by an
occlusive coronary thrombus at the site of a pre-existing atherosclerotic
lesion [Fuster, 1999]
- the severity of the clinical picture and the prognosis are,
to a large extent, related to the size and anatomical location
of the myocardial infarction
- extension of myocardial damage may occur in the case of impaired
collateral circulation or further thrombotic events in the adjacent
coronary arteries
- life-threatening complications of myocardial infarction include
post-infarction ischaemia, arrhythmia, myocardial dysfunction
and ventricular failure, cardiogenic shock, rupture of papillary
muscles or of the inter-ventricular septum, myocardial rupture
and left ventricular aneurysm
Cerebral infarction
- cerebral infarction caused by atherosclerosis and thrombosis
of cerebral vessels represents a significant fraction of the
cases of stroke
- a frequent cause of obstruction of the cerebral vessel is
represented by emboli derived from ulcerated plaques on a major
artery to the brain
- atherosclerotic plaques often occur in the region of carotid
bifurcation extracranially [Iannuzzi,
1995]
- cerebral infarction might also be produced by emboli of cardiac
origin and is associated with rheumatic heart disease, mitral
valve disease, arrhythmia and mural thrombi complicating an
acute myocardial infarction. The resulting neurological deficit
depends upon the particular vessel involved and the extent of
compensation via the collateral cerebral circulation
Transitory ischaemic attack
- the condition of a focal ischaemia causing a neurological
deficit that lasts for less than 24 hours is called a transitory
ischaemic attack
- a transitory ischaemic attack is generally caused by emboli
in the cerebral circulation and often occurs without leading
to cerebral infarction (as a result of spontaneous fibrinolysis
or effective collateral circulation)
- approximately 30% of patients with stroke have a history of
transitory ischaemic attacks
Aortic and peripheral atherosclerosis
- atherosclerotic disease of the aorta and its branches (peripheral
atherosclerosis) is a major cause of disability
- obliterating arterial disease of the lower limbs (in some
cases manifested as intermittent claudication), mesenteric ischaemia
leading to recurrent abdominal pain or renal ischaemia associated
with hypertension are the consequences of thrombosis complicating
atherosclerotic plaques
- abdominal aortic aneurysms (arterial dilatation complicating
severe atherosclerosis) may be asymptomatic for years and are
most often diagnosed when an echography of the abdomen is undertaken
for other reasons
- abdominal aortic aneurysms manifest themselves at the time
of the rupture with back or abdominal pain and carry a very
poor prognosis if elective surgical resection is not performed
before rupture
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