Overview of Cardiovascular Nancy Long Sieber, Ph.D. September 19, 2011 ...

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Transcript of Overview of Cardiovascular Nancy Long Sieber, Ph.D. September 19, 2011 ...

Overview of Cardiovascular

Nancy Long Sieber, Ph.D.

September 19, 2011

http://www.flickr.com/photos/glockoma/398476805/in/set-72157594209628957/

Fig. 12.01

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.

Fig. 12.47

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 controlledControl of blood flow to organs and tissues

Capillaries and venulesExchange of nutrients, waste, and fluid between the blood and interstitiumLargest cross-sectional area and slowest flow

VeinsLow resistance conduits that return blood to the heartBlood storage reservoir – can be mobilized as needed

The Skeletal Muscle Pump

http://www.nlm.nih.gov/medlineplus/ency/imagepages/18072.htm

An Aortic Aneurysm

http://www.vascularweb.org/graphics/northpoint_graphics_jpg/Varicose_02_Base_300.jpg

Varicose Veins

Fig. 12.06

Cardiac Muscle

http://content.answers.com/main/content/img/oxford/Oxford_Body/019852403x.cardiac-muscle.1.jpg

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

Atrial Fibrillation

http://www.lhsc.on.ca/uwodoc/media/fib2.gif

Two normal beats, followed by ventricular fibrillation

http://noodle.med.yale.edu/~staib/bme355/ecg/vfib.jpg

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

http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/19613.jpg

http://connection.lww.com/Products/taylor5e/documents/Ch25/jpg/25_039.jpg

Heart SoundsS1 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.

www.mvprolapse.com/mvp.html

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.

http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/18148.jpg

Mitral Valve Prolapse

http://www.abcbodybuilding.com/magazine03/wrench/tensionlevels2.jpg

The length-tension relationship

Children with Kwashiorkor

http://www.cs.stedwards.edu/chem/Chemistry/CHEM43/CHEM43/Leukotr/Kwashiorkor.GIF