Anatomy and Physiology II: Cardiovascular Ch. 18

Objective Five: Explain why the heart is termed the "double pump." Contrast this description to the actual action of the atria and ventricles as functional units.

Although it is easier to see working on one side of the heart at a time, in reality both the right AND left sides of the heart are working (almost) simultaneously.

S-T Elevation

An upward drift of the ECG during indicating early ventricular repolarization, often due to a myocardial infarction

Murmur

Any time blood is moving around in the heart in a way it shouldn't (VSDs, ASDs, mitral valve prolapse, aortic stenosis)

Arythmia

Any time there is an abnormal sinus pattern (basically if one of the other nodes is contracting faster than the SA node)

Autonomic regulation of heart rate is via two reflex centers found in the pons True/False

False

Increasing end-diastolic and end-systolic volume will increase stroke volume True/False

False

Tachycardia/Bradycardia

Increase in HR/decrease in HR

Pathway of Blood through the Heart (Objective Four)

Inferior and Superior Vena Cava ---> R. Atrium ---> Tricuspid Valve ---> R. Ventricle ---> Semilunar Valve ---> Pulmonary Artery (Deoxygenated Blood) ---> Lungs --->R. and L. Pulmonary Veins (Oxygenated Blood) ---> L. Atrium ---> Mitral (Bicuspid) Valve ---> L. Ventricle ---> Aortic Valve ---> Aorta ---> Brachiocephilac Trunk, Left Common Carotid Artery, and Left Subclavian Artery

Endocardium (Objective Two)

Innermost layer of the heart wall; lines heart chambers and covers the valves

Myocardium (Objective Two)

Middle layer of the heart wall; myo-muscle, or the layer that contracts -Circular cardiac muscle bundles allow all of the parts of the heart to be connected

Systole

Refers to periods of contraction

Diastole

Refers to periods of relaxation

Lubb-Dupp noise (Objective Eight)

The "lubb" is the first heart sound, commonly termed S1, and is the turbulence of blood caused by the closure of mitral and tricuspid valves at the start of systole The "dupp" or S2, is caused by the closure of aortic and pulmonary valves, marking the end of systole

Pulmonary Circulation (Objective Six)

The blood vessels that carry blood to and from the lungs; the right side of the heart receives oxygen-poor blood from body tissues then pumps this blood to the lungs to pick up oxygen and dispel CO2

Blood within the pulmonary veins returns to the ____. a. left atrium b. left ventricle c. right ventricle d. right atrium

a.

If the vagal nerves to the heart were cut, the result would be that___. a. the heart rate would increase by 25 bpm b. parasympathetic stimulation would increase, causing a decrease in heart rate c. the heart would stop, since the vagal nerves trigger the heart to contract d. the atrioventricular (AV) node would become the pacemaker of the heart

a.

Normal heart sounds are caused by which of the following events? a. closure of the heart valves b. friction of blood against the chamber walls c. opening of the heart valves d. excitation of the sinoatrial (SA) node

a.

Specifically, what part of the intrinsic conduction system generates the original stimulus that reaches the atrioventricular (AV) node, allowing it to conduct impulses to the atrioventricular bundle? a. sinoatrial (SA) node b. subendocardial conducting network (Purkinje fibers) c. bundle branches d. interventricular septum

a.

Which heart chamber receives oxygenated blood from the lungs? a. left atrium b. right ventricle c. left ventricle d. right atrium

a.

Which of the following descriptions does NOT describe atrioventricular (AV) valves? a. pocket-like b. anchored inferiorly by specilized connective tissue c. open based on pressure changes in the atria versus the ventricles d. flap-like

a.

Which of the following is NOT part of the intrinsic conduction system of the heart? a. atrioventricular (AV) valve b. bundle branches c. sinoatrial (SA) node d. atrioventricular (AV) node

a.

Which of these muscles is particularly associated with anchoring the right and left atrioventricular valves? a. papillary muscles b. pectinate muscles c. myocardium d. trabeculae carneae

a.

Which statement is correct regarding the ventricles? a. The right ventricle empties into the pulmonary trunk b. The right ventricle forms a complete circle in cross section c. The left ventricle has a thinner wall than the right ventricle d. The left ventricle empties into the pulmonary circuit

a.

Which of the events below does NOT occur when the semilunar valves are open? a. Ventricles are in systole b. Ventricles are in diastole c. AV valves are closed d. Blood enters pulmonary arteries and the aorta

b

Consider the following characteristics of the cells found in muscle tissue. Which feature is shared by both cardiac muscle and skeletal muscle? a. branched cells b. striations c. intercalated discs d. triads

b.

Norepinephrine acts on the heart by ____. a. causing a decrease in stroke volume b. causing threshold to be reached more quickly c. blocking the action of calcium d. decreased heart contractibility

b.

Which of the following increases stroke volume? a. severe blood loss b. exercise c. decrease in preload d. decrease in end diastolic volume (EDV)

b.

Which of these vessels returns blood to the left atrium of the heart? a. coronary sinus b. pulmonary veins c. pulmonary trunk d. superior vena cava

b.

Which of the following would increase cardiac output? a. decreased calcium during contraction b. high blood pressure c. epinephrine d. parasympathetic stimulation

c.

Which statement regarding cardiac muscle structure is accurate? a. Cardiac cells are long, cylindrical, and multinucleate b. Cardiac cells possess few mitochondria c. Myofibrils of cardiac muscle tissue vary in diameter and branch extensively. d. Cardiac muscle cells are independent of one another both structurally and functionally.

c.

Which of the following receive(s) blood during ventricular systole? a. pulmonary veins only b. aorta only c. pulmonary arteries only d. both the aorta and pulmonary trunk

d

At what rate does the sinoatrial (SA) node depolarize? a. 30 times per minute b. 40 times per minute c. 50 times per minute d. 75 times per minute

d.

Given an end diastolic volume (EDV) of 120 mL/beat and an end systolic volume (ESV) of 50 mL/beat, the stroke volume (SV) would be_____. a. 50 mL/beat b. 170 mL/beat c. 120 mL/beat d. 70 mL/beat

d.

If we were able to artificially alter the membrane permeability of pacemaker cells so that sodium influx is more rapid, ____. a. potassium channels compensate and no change in heat rate would occur b. heart rate would decrease, but blood pressure would rise due to the excess sodium present c. tetanic contraction would occur due to the short absolute refractory refractory period of cardiac muscle d. threshold is reached more quickly and heart rate would increase

d.

The first heart sound (the "lub" of the "lub-dup") is caused by a. atrial contraction b. ventricular contraction c. closure of semilunar valves d. closure of the atrioventricular valves

d.

The right atrioventricular valve prevents backflow of blood from the right ventricle into the _____. a. pulmonary trunk b. left ventricle c. left atrium d. right atrium

d.

What best describes afterload? a. contractility of cardiac muscle b. degree of stretch of the heart muscle c. cardiac muscle d. back pressure exerted by arterial blood

d.

When viewing a dissected heart, it is easy to visually discern the right and left ventricles by ____. a. finding the papillary muscles b. tracing out where the auricles connect c. locating the base d. noticing the thickness of the ventricle walls

d.

Which description is INCORRECT for the layers of the heart and its serous membranes? a. The fibrous pericardium prevents overfilling of the ventricles b. The endocardium is the deepest of the layers related to the heart. c. The parietal pericardium is on the deep side of the fibrous pericardium d. The epicardium is also considered the parietal pericardium

d.

Which of the following factors does NOT influence heart rate? a. gender b. age c. body temperature d. skin color

d.

Coronary Circulation (Objective Seven)

-Left Coronary Artery: runs toward the left side of the heart and divides into two major branches: -Anterior Interventricular Artery: supplies interventricular sulcus and anterior walls of both ventricles; "The Widowmaker" -Cicrumflex Artery: supplies the left atrium and the posterior walls of the left ventricle -Right Coronary Artery: courses to the right side of the heart and divides into two major branches: -Right Marginal Artery: Serves the myocardium of the lateral side of the heart -Posterior Interventricular Artery: Runs to heart apex and supplies the posterior ventricular walls

Coronary Circulation and Disease (Objective Seven)

-Myocardial Infarction- e.g. heart attack; plaque buildup in the artery blocking blood flow and O2 to the heart -Angina- A type of chest pain, pressure, or discomfort; heart is not receiving enough oxygen due to narrowed coronary artery -Ischemia- inadequate blood supply to heart muscles

EKG Pattern

-P Wave: Movement of current from SA node through atria (atrial depolarization) -0.1 s after P wave begins, atria contract -Q Wave: Movement of ventricular excitation; not typically visible -QRS Complex- Ventricular depolarization begins at apex; atrial repolarization. Duration of QRS is determined by the time required for each ventricle to depolarize, which is determined by relative size. Usually 0.08s. -T Wave: Ventricular repolarization. Usually 0.16 s -P-R Interval: time from the beginning of atrial excitation to the beginning of ventricular excitation. -S-T segment: when the action potentials of the ventricular myocytes are in their plateau phrases, the entire ventricular myocardium is depolarized.

Objective One: Sketch and label the fibrous and serous pericardium layers. Include the pericardial cavity and epicardium.

-Pericardium: double-walled sac that encloses the heart -Fibrous pericardium: loosely fitting durable outer layer made of connective tissue; protects the heart; anchors heart to surrounding structures; prevents overfilling of the heart -Serous Pericardium: thin inner layer -Parietal layer: "outer layer" that makes contact with fibrous pericardium; attaches to the arteries exiting the heart -Pericardial Cavity: contains serous fluid to allow heart to move in friction-free environment