Cardiac Muscle

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Cardiac Muscle
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Cardiac Muscle
Moderate Striations Branched Together Single
Nucleus Regulated by Internal Pacemaker Cells
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Structural Organization
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Cardiac Muscle
The Cardiac Conduction System
Although all of the heart's cells possess the
ability to generate electrical impulses a
specialized portion of the heart, called the
sinoatrial node, is responsible for the whole
heart's beat.
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Cardiac Muscle
Cardiac muscle of an organized group of muscle
cells or fibers that branch and form a complex
organ of the circulatory system. Heart muscle
cells need an abundance of oxygen and nutrients.
Tiny capillaries (orange), containing red blood
cells, course through the muscle carrying
nutrients and oxygen.
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Cardiac Muscle
Specialized fibers called Purkinje Fibers (green)
are located throughout the heart. They conduct
the electrical impulse from the pacemaker region
(AV node) to the ventricles to contract enabling
almost simultaneous contraction. The spread of
excitation through the ventricles from the AV
node is extremely rapid.
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Atherosclerosis
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Chest Pain
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Chest PainDifferential Diagnosis
Chest Pain
Cardiac Chest Pain
Non-Cardiac Chest Pain
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Non-Cardiac Chest PainDifferential Diagnosis
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Coronary Artery Disease
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Angina Pectoris
Chest Pain
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Myocardial Infarction
Heart Muscle Death
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Myocardial Infarction
Heart Muscle Death
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But Wait!
What if we could intervene here before a
significant amount of myocardium is dead?
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Thrombolytics Clot Breakers
Dissolve Forming Clots Very Dangerous if patient
has an occult bleed (lethal)
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Thrombolytic Therapy
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Thrombolytics Work
Clot is Resolved just hours later
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Smooth Muscle
Walls of Hollow Organs
Walls of Blood Vessels
Pulmonary Tree
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Smooth Muscle
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Blood Vessels
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Blood Vessels
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Normal Endothelium
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AtherosclerosisPlaque Formation
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Smooth Muscle Pathogenesis of
Atherosclerosis
Smooth Muscle Cell Proliferation (growth) as a
consequence of rising pressure associated with a
growing cholesterol plaque.