The heart and the circulatory system, both systemic and pulmonary, comprise one of the most essential parts of the body.  Failure to function results in death of the organism.  The heart is a hollow, muscular organ which, by contracting rhythmically, effectively pumps the blood through the circulatory system to nourish all of the body tissues.  Diseases related to the cardiovascular system are the leading cause of death in the U.S.  CV health problems occur across the age continuum

To reduce death and disability, three major objectives include early detection of the disease, appropriate treatment to control the disease progression, and reduction of predisposing factors by promoting screening, education, and patient care of cardiovascular health.

Shape--hollow, cone-shaped muscular organ

Size—approximately size of your fist

Fcns—as a pump

Positioned in thoracic cavity between the sternum & thoracic vertebrae

 --apex extends slightly to the left and rests on the diaphragm, approx at the level of the  5th rib

  --stethoscope should be placed at the apex to count an apical pulse

Pericardium—outer covering, 2 layers of serous membrane that is lubricated and prevents friction when the heart beats

Myocardium—dense fibrous connective tissue, the wall of the heart

Endocardium—thin, serous lining that helps blood flow smoothly through the heart, lines the heart chamber

Atria—upper chambers; primarily receiving chambers; not important in the pumping action of the heart

Afterload:  resistance the left ventricle must overcome to circulate blood

• Increased in hypertension, vasoconstriction

Preload:  volume coming into ventricles

• Increased in hypervolemia, regurgitation of cardiac valves

semilunar valves:  prevent backflow from the aorta and pulmonary arteries into the ventricules during diastole

dysrhythmia:  definition

(bradycardia / tachycardia)

dyshythmia:  an irregularity in the rate, rhythm or conduction of the electrical system of the heart

• may occur in atria, ventricles or anywhere within the electrical system
• bradycardia - less than 60 beats / min
• tachycardia - greater than 100 beats / min

• one complete heart beat
• consist of contraction (systole) & relaxation (diastole) of the atria and ventricles

• heart is affected by a condition within the lungs, CO2 level increases in blood
• pulmonary arteries constrict causing pulmonary HTN
• right ventricle being forced to pump against the pressure enlarges and then weakens

• membranous sac surrounding the heart is inflamed
• causes:  viral, bacterial, fungal, parasites, rheymatic or collagen-vascular conditions radiation therapy
• signs and symptoms:  severe precordial (chest) pain, more severe on inspiration, relieved by sitting up, irritability, restlessness, difficulty swallowing, tachycardia, low-fever, pericadial frictin rub; may lead to cardiac tamponade (fluid rapidly increases and hinders function of ventricles)
• treatment:  rest, meds (analgesics, NSAID's, ABX, antipyretics, digitalis and diuretics to improve pumping action of heart

coronary artery disease:  occurs when coronary arteries supplying myocardium are blocked by spasm, arteriosclerosis, or atherosclerosis

arteriosclerosis:  abnormal thickening, hardening or loss of elasticity of arterial walls

• secondary to trauma to tunica intima

atherosclerosis:  thickening and hardening of vessel wall caused by soft deosits of fat and fibrin that harden over time

• fatty streak
• earliest lesion to develop
• yellow-colored lipids
• cause no obstruction and no symptoms
• thought to be reversible