Circulatory System Lecture: Cardiovascular and lymphatic

1. Functions include: exchange & transportation




2. Cardiac Muscle Tissue revisited: uninucleate, branched, striated, intercalated disks are where two cells come together and join tightly like clasped fingers, and gap channels












3. Blood Vessel Structure: veins, arteries and capillaries















4. The Heart

††††††††††† a. location and size: apex towards left hip base points to rt shoulder






b. coverings and wall: pericardium (double sac of serous membranes) secrete serous fluid, visceral/ epicardium hugs external surface of heart

        @ apex: connects parietal pericardium from heart to diaphragm and sternum

        heart wall has 3 layers: 1.


3._______________: lines cavity chambers of the heart and continues to vessels (think glistening sheet)

††††††††††††††††††††††† Sulci:

††††††††††††††††††††††† a)

††††††††††††††††††††††† b) †††††††

††††††††††††††††††††††† c)


††††††††††††††††††††††† Pericarditits:



††††††††††††††††††††††† Cardiac tamponede



††††††††††† c. chambers and associated vessels

        4 chambers: 2 atria (receive blood) and 2 ventricles (pump blood out)

        rt atria receives blood from vena cava; lt atria receives blood from lungs

        rt side is pulmonary pump

        rt ventricle: most anterior surface

        left ventricle: apex

        lt side: systemic pump













††††††††††† d. valves

        atrioventricular valves:



o       a)


o       b)



chordae tendinae:


o       semilunar valves (3 cusps fit tightly together)

o       when ventricles contract semilunar valves open and blood rushes through

o       a)

o       b)

o       Leaky valves: incompetent valve: heart repumps same blood: ____________________________

o       Valvular stenosis: valves become stiff (bacterial infection of myocardium)

o       Any condition where valves act improperly: ______________



††††††††††† e. cardiac circulation

o       ____________ arteries feed the heart while the ventricles ______; branch out from the aorta down the atrioventricular groove

o       cardiac veins empty into _________________________ and empties into right ___________

o       If heart rate increases (too rapid)myocardium may not receive enough blood (no oxygen) crushing chest pain = _____________________, if angina is prolonged then the ischemic heart cells die = infarct = myocardial infarct = ________________


o       Myocardial Infarct:







2 types of control to regulate

††††††††††††††††††††††††††††††††††† 1. ANS: para and sympathetic (LECTURE ON LATER)

††††††††††††††††††††††††††††††††††† 2. _________________ conduction system (_________)

o       Tissue is _______________ and ____________


o       Muscle depolarization is one way: atria to ventricle (75 beats per min)



o       ________________________________________________) has the highest rate of depolarization


o       Can slow down




o       Atrioventricular node (av node and bundle of his)




o       Rt and left branches (septum)


o       Purkinje fibers spread into ventricles walls


††††††††††† g. Cardiac cycle/heart sounds

o       Systole: ______________††††††††††††††††† diastole: ________________

o       ________________ _________: both atria and ventricles contract in 8 sec

o       3 Periods:






b. ventricular systole:




c. ________________ ventricles are completely closed chambers

o       lub = closing of ________________

o       dub = closing of _____________________


o       Murmurs: unusual heart sounds, indicate valve problems





††††††††††† h. Cardiac output: (CO) regulation of stroke volume and heart rate

o       CO :


o       SV:




††††††††††††††††††††††† ††††††††††† Ex. 5200 ml/min = 70 ml/beat X 75 beats /min

o       If SV is low then HR _________________________________

o       ______________________________: SV controlled by how much cardiac muscle cells are stretched depends on venous return


Although heart rate is independent, the ANS, ions and hormones can modify heart rate. Sympathetic nerve can stimulate SA and AV node

Parasympathetic or vagus nerve slows down/steadies heart

††††††††††††††††††††††† Hormones: epinephrine (mimics sympathetic ) and thyroxine

††††††††††††††††††††††† Ca+ is low: ____________________

††††††††††††††††††††††† Ca+ is high _________________________________________

††††††††††††††††††††††† K+ is low causes ____________________________________________


Congestive heart failure: pumping efficiency is low = inadequate blood to tissue, usually progressive by atherosclerosis

††††††††††††††††††††††† Left side of heart fails: _____________________________


5. Major Blood Vessels

††††††††††† a. systemic circulation :

††††††††††† b. pulmonary circulation :


6. Special circulation

††††††††††† a. circulation of willis:

b. hepatic portal:




c. fetal:







7. Blood Pressure

††††††††††† a. systolic


††††††††††† b. diastolic


††††††††††† c. what does it mean?



8. Lymphatic system

a. organs:



b. vessels



††††††††††† c. nodes


9.Monitoring EKG (electrocardiogram)

            a. graphical recording of the electrical events occurring within the heart

            b. 5 identifiable deflections:

                        a. P wave:

                        b. Q,R,S complex

                        c. T wave:

















††††††††††† Interpretation:

        By looking at time intervals between cardiac events and comparing them to standard values, one can determine if a personís heart has sustained any damage that will alter the muscle cells ability to conduct an electrical signal.

Ex. In first degree heart block______________________________________________________________________________________________________.


        In order for a problem to be detected by an EKG, the disease must ________________________________________________________________________________________________________________________

        Many diseases affect the heart without altering its electrical properties. A physical defect such as ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

        The most common problems that can be diagnosed from an EKG are

1.      _____________________________:




2.      _____________________________:





3.      ______________________________:



Heart block:



††††††††††† Sinoatrial block




††††††††††† Atrioventricular block



††††††††††† ††††††††††† Incomplete heart attack: partial block


††††††††††††††††††††††† Due to :

††††††††††††††††††††††† 1.

††††††††††††††††††††††† 2.

††††††††††††††††††††††† 3.

††††††††††††††††††††††† 4.






















††††††††††† Atrial



††††††††††† Ventricular