Cardiovascular System (A&P). The Cardiovascular System. A closed system of the heart and blood vessels The heart pumps blood Blood vessels allow blood to circulate to all parts of the body
MYOCARDIUM IS CRISS-CROSSED
Muscle tissue is CONTRACTILE tissue.
Cardiac Muscle Cells are Small, w/ a single nucleus. Short cells.
Involuntary contractionsMyocardium = Muscular Wall =Cardiac Muscle
Scarred Valves Sometimes become STENOTIC (THEY CUFFS BECOME STIFFED AND CONSTRICT…DON”T OPEN) Valvular Stenosis
Heart then overworks to force blood through and valves become enlarged
Backflow (regurgitation) through these new incompetent valves creates turbulence or HEART MURMER.
Intrinsically by the NODAL System:
The Autonomic Nervous System:Sympathetic Nervous: Fight or Flight- speeds it up Parasympathetic slows it down
Why? As you get in better shape, your heart will automatically pump more blood with each beat; and therefore, the rate of contractions (that’s the number of times it beats) will be less when doing the same amount of work. Less heart stress results in more energy saved.
SO we are referring to the
SYSTOLE- period when the heart CONTRACTS ( blood pressure is highest when left ventricle is contracting or ejecting into the aorta….120)
1. Pump cuff until pressure cuts off artery flow.
2. Release cuff SLOWLY so blood will spurt ..this happens only during ventricular contraction ( SYSTOLE) THE FIRST SOUND YOU HEAR
4. Listen until you hear no more clicking. This means blood is flowing continously ..no more spurting…Ventricular relaxation..DIASTOLE
Systolic pressure (mmHg)
Diastolic pressure (mmHg)
Table 1. Some 'average'
How fat and plaque deposits on arteries can lead to arteriosclerosis and Hear Attack
Cross Section of a healthy artery. The inside of the artery is free and provides unobstructed flow of blood.
Arteries are gradually getting clogged by fatty deposits on the vessel wall. Note that the opening for the flow of blood is now reduced. But there is still space for blood to flow through.
Advanced hardening of the artery. Fatty deposits now clog most of the artery opening. But small amount of blood (shown in red) still flow through.
Blood clot (shown in blue) now blocks the small opening, cutting off the flow of blood completely. This leads to heart attack.
Harms the CVS in several ways:
Exercise: can reverse a sedentarylifestyle; and is known to be “magic bullet” for healthy heart.
Lowers BP, raises HDLs, maintains healthy weight, prevents or helps control diabetes and improves the functioning of endothelial cells that line the coronary arteries.
A minimum of 30 to 60 minutes per day of moderate physical activity is recommended.
Exercise Mechanism: LOWERS VLDLs., raises HDLs (this is one)