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Alteration of Heart Function
Key Terms
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Hypertension
Thromboxane A2
Serotonin
Hyperlipidemia
Hyperhomocystemia
Hemodynamic Factors
Plaque
Angioplasty
Atherosclerosis
Hyperemia
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Anastomose
Infarction
Stenosis
Aneurysm
Beta Blocker
ACE Inhibitor
CCB
ARB
http://www.youtube.com/watch?v=hCp4hVC2
fnM
Heart Function
Monitoring Echo of Heart
Heart Echogram
ATHEROSCLEROSIS
• A form of arteriosclerosis in which soft deposits
of intraarterial fat and fibrin on the vessels walls
harden over time.
• It is the leading contributor to coronary artery
and cerebrovascular disease.
• Begins with injury to the endothelial cells that
line artery walls. – ENDOTHELIAL INJURY.
– Smoking
– Hypertension
– Diabetes
There
is a pink to red recent thrombosis in this narrowed coronary artery. The open, needlelike spaces in the atheromatous plaque are cholesterol clefts.
There
is a severe degree of narrowing in this coronary artery. It is "complex" in that there is a
large area of calcification on the lower right, which appears bluish on this H&E stain. Complex
atheroma have calcification, thrombosis, or hemorrhage. Such calcification would make
coronary angioplasty difficult.
This
section of coronary artery demonstrates remote thrombosis with recanalization to leave
only two small, narrow channels.
The
coronary artery shown here has narrowing of the lumen due to build up of atherosclerotic
plaque. Severe narrowing can lead to angina, ischemia, and infarction.
This
cross section through the heart demonstrates the left ventricle on the left. Extending from
the anterior portion and into the septum is a large recent myocardial infarction. The center is
tan with surrounding hyperemia. The infarction is "transmural" in that it extends through the full
thickness of the wall.
Put
down that extra slice of pizza and look carefully at this aorta. The white arrow
denotes the most prominent fatty streak in the photo, but there are other fatty streaks
scattered over the aortic surface. Fatty streaks are the earliest lesions seen with
atherosclerosis in arteries. Increased total cholesterol and decreased HDL cholesterol
contribute to this process.
This coronary artery demonstrates yellowish atherosclerotic plaques
grossly.
Here is the coronary thrombosis at higher magnification. The
thrombus occludes the lumen and produces ischemia and/or
infarction of the myocardium.
This
patient underwent coronary artery bypass grafting with autogenous vein (saphenous vein)
grafts. The largest of these runs down the center of the heart to anastomose with the left
anterior descending artery distally. Another graft extends in a "Y" fashion just to the right of this
to branches of the circumflex artery. A white temporary pacing wire extends from the mid left
surface.
THE CARDIOMYOPATHIES
• The cardiomyopathies are a diverse group of
diseases that primarily affect the myocardium
itself and are not secondary to the usual
cardiovascular disorders
• Categorized as dilated (formerly, congestive),
hypertrophic, or restrictive, depending on
their physiologic effects on the heart.
This
is the left ventricular wall which has been sectioned lengthwise to reveal a large recent
myocardial infarction. The center of the infarct contains necrotic muscle that appears yellowtan. Surrounding this is a zone of red hyperemia. Remaining viable myocardium is reddishbrown.
One
complication of a transmural myocardial infarction is rupture of the myocardium. This is
most likely to occur in the first week between 3 to 5 days following the initial event, when the
myocardium is the softest. Note the dark red blood clot forming the hemopericardium. The
hemopericardium can lead to tamponade.
In cross section,
the point of rupture of the myocardium is shown with the arrow. In this case,
there was a previous myocardial infarction 3 weeks before, and another myocardial infarction
occurred, rupturing through the already thin ventricular wall 3 days later.
This very
large heart has a globoid shape because all of the chambers are dilated. It felt
very flabby, and the myocardium was poorly contractile. This is an example of a
cardiomyopathy. This term is used to denote conditions in which the myocardium
functions poorly and the heart is large and dilated, but there is no specific histologic
finding.
AORTIC STENOSIS
• Aortic stenosis has 3 common causes:
– Inflammatory damage caused by rheumatic heart
disease
– Congenital malformation
– Degeneration resulting from calcification.
• The orifice of the aortic semilunar valve narrows, causing
diminished blood flow from the left ventricle into the
aorta.
• Tends to develop gradually.
• A crescendo-decrescendo systolic heart murmur
develops.
• LVH develops to compensate for the increased work load.
Total Cholesterol Level
Category
Less than 200 mg/dL
Desirable
200-239 mg/dL
Borderline High
240 mg/dL and above
High
LDL Cholesterol Level
LDL-Cholesterol Category
Less than 100 mg/dL
Optimal
100-129 mg/dL
Near optimal/above optimal
130-159 mg/dL
Borderline high
160-189 mg/dL
High
190 mg/dL and above
Very high
HYPERTENSION
• All stages of hypertension are associated with increased risk
of cardiovascular disease events.
• Stage 1 is the most common form of high blood pressure in
the adult population.
• Hypertension is caused by increases in cardiac output, total
peripheral resistance, or both.
– Cardiac output is increased by conditions that increase
heart rate or stroke volume, whereas peripheral resistance
is increased by factors that increase blood viscosity or
reduce vessel diameter, particularly the arterioles.
ANEURYSM
• Localized dilation or outpouching of a vessel wall or
cardiac chamber.
• A ventricular wall aneurysm forms when
intraventricular tension stretches the contracting
infarcted muscle.
• The aorta is particularly susceptible to aneurysm
formation because of constant stress on the vessel
wall and the absence of penetrating vasavasorum in
the adventitial layer.
– ¾ of all aneurysms occur in the abdominal aorta.
This is coronary
thrombosis, one of the
complications of
atherosclerosis. The
dark red thrombus is
seen in the anterior
descending coronary
artery.
The main pulmonary trunk and pulmonary arteries to
right and left lungs are seen here opened to reveal a
large "saddle" pulmonary thromboembolus. Such an
embolus will kill your patient.
This pulmonary thromboembolus is occluding the main
pulmonary artery. Persons who are immobilized for weeks are
at greatest risk. The patient can experience sudden onset of
shortness of breath. Death may occur within minutes.
HEART FAILURE
• A general term used to describe several types of cardiac
dysfunction that result in inadequate perfusion of tissues
with vital blood-borne nutrients.
• LEFT HEART FAILURE is commonly called CONGESTIVE
HEART FAILURE.
– SYSTOLIC HEART FAILURE is defined as an inability of
the heart to generate an adequate cardiac output to
perfuse vital tissues.
– Contractility is reduced by diseases that disrupt
myocyte activity.
HEART FAILURE
– Myocardial infarction is the most common cause of
decreased contractility.
– VENTRICULAR REMODELING causes progressive myocyte
contractile dysfunction over time.
– When contractility is decreased, stroke volume falls and
left ventricular end-diastolic volume (LVEDV) increases.
– Dilation of the heart occurs and preload is increased.
– Increased afterload is most commonly a result of increased
peripheral vascular resistance (PVR).
– With increased PVR, there is resistance to ventricular
emptying and more workload for the left ventricle.
HEART FAILURE
• A general term used to describe several types of cardiac
dysfunction that result in inadequate perfusion of tissues
with vital blood-borne nutrients.
• LEFT HEART FAILURE is commonly called CONGESTIVE
HEART FAILURE.
– SYSTOLIC HEART FAILURE is defined as an inability of
the heart to generate an adequate cardiac output to
perfuse vital tissues.
– Contractility is reduced by diseases that disrupt
myocyte activity.
Mitral stenosis. Mitral stenosis and clumps of vegetation (V) containing platelets and fibrin as
shown in this micrograph. Mitral leaflets are thickened and fused.
HYPERTENSION
• OPTIMAL BLOOD PRESSURE (Systolic <120, diastolic
<80) is associated with the lowest cardiovascular risk.
• HIGH NORMAL (Systolic 130-139, diastolic 85-89) is at
significant risk of developing hypertension unless lifestyle
modification is initiated.
• HYPERTENSION
– STAGE 1 (mild): systolic 140-159, diastolic 90-99
– STAGE 2 (moderate): systolic 160-179, diastolic 100109
– STAGE 3 (severe): systolic > 180, diastolic > 110
Brain Project Draws Presidential Interest
by Emily Underwood and Jocelyn Kaiser
on 20 February 2013, 2:00 PM
http://news.sciencemag.org/sciencei
nsider/2013/02/brain-project-drawspresidential.html?ref=em