Overview of Cardiovascular Nancy Long Sieber, Ph.D. September 19, /in/set /

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Blood Cells

Abnormal Blood Counts Too many red blood cells and platelets: polycythemia vera, certain blood cancers Too few red blood cells: anemia, due to insuffient iron in the diet, hemolysis, chemotherapy Too many white blood cells: leukemia and other other blood cancers Too few white blood cells: AIDS, other immune deficiencies, chemotherapy

Fluid Spaces Intravascular (first space) Interstitial (second space) “Third space” - interstitial spaces that expand as the result of injury or disease. Eg: swelling at site of surgical incision, edema in abdominal cavity.

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Elephantiasis: The swelling results from blocked lymphatic vessels

The distribution of blood flow at rest and during exercise. Note how blood conditioning organs (the kidneys and abdominal organs) are able to withstand a significant reduction in blood flow during exercise.

The vascular system Arteries Low resistance conduits Highly elastic Arterioles Major site where total peripheral resistance (TPR) is controlled Control of blood flow to organs and tissues Capillaries and venules Exchange of nutrients, waste, and fluid between the blood and interstitium Largest cross-sectional area and slowest flow Veins Low resistance conduits that return blood to the heart Blood storage reservoir – can be mobilized as needed

The Skeletal Muscle Pump

An Aortic Aneurysm

Varicose Veins

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Cardiac Muscle Body/ x.cardiac-muscle.1.jpg

Normal ECG (a), partial AV block(b) complete AV block (c)

Atrial Fibrillation

Two normal beats, followed by ventricular fibrillation

Hypothermia can lead to a characteristic Osborn (or “J”) wave at the end of the QRS complex. A 12-lead ECG obtained at core body temperature of 85°F. Note Osborn waves, an extra deflection at end of QRS complex (arrows). From: Circulation June 27, 2000 vol. 101 no. 25 e233-e244

Electrolyte imbalances can interfere with the cardiac rhythm, potentially leading to cardiac arrest. Examples: Eating disorders and other types of malnutrition. Hyponatremia – can result from over consumption of water. People who are on antidiuretic drugs may also develop levels of K+ that are too high or too low.

Heart Sounds

Heart Sounds S1 and S2 are normal S3 and S4 are abnormal

Extra Diastolic Sounds: S3 S3 is produced by the tensing of the chordae tendineae, which occurs during rapid filling and expansion of the ventricles. Common in children and young adults – the flexible ventricles of young people can expand rapidly. In middle-aged or older adults often indicates excessive volume in the ventricles, which usually indicates heart failure.

Extra Diastolic Sounds: S4 Produced by the left or right venticle contracting against a stiffened ventricle Usually indicates a loss of compliance of the ventricle due to ventricular hypertrophy or myocardial ischemia

The heart murmur associated with mitral valve prolapse Mitral valve prolapse causes a late systolic murmur

Mitral valve prolapse is an example of valve insufficiency. Abnormally shaped valve leaflets are pushed into the left atrium during late systole. Mitral Valve Prolapse

The length-tension relationship

Children with Kwashiorkor