Pulse / Heart Rate

T or F: The first heart sound (S1) is caused by closure of the AV valves and the second heart sound (S2) is caused by closure of the SL valves.

True

Cardiac output is the volume of blood pumped by each ventricle per minute. The cardiac output is the product of:

Cardiac output is the product of stroke volume & heart rate (CO = SV x HR).

How would you expect the VSD to affect Isabelle's cardiac output?

Cardiac output would decrease because stroke volume would decrease.

T or F: Oxygenated blood flows from the pulmonary circulation into the right atrium via the pulmonary veins.

False

T or F: The AV node is considered the heart's pacemaker.

False --the SA node is considered the pacemaker.

In what, if any, manner would you expect a VSD to alter the flow of blood through Isabelle's heart?

I would expect that some blood would flow from the left ventricle to the right ventricle during systole due to higher pressure in the left ventricle during systole

Which of the following factors can increase cardiac output?

Increasing heart rate, increasing the contractility of the heart (i.e., increasing the forcefulness of contraction), increasing end diastolic volume

Choose the answer that correctly depicts the order of blood flow through a normal heart and major blood vessels:

Right atrium > right ventricle > pulmonary trunk > pulmonary veins > left atrium > left ventricle > aorta

Choose the answer that correctly depicts the order of impulse conduction in the cardiac conduction system.

SA node > AV node > AV bundle > left and right bundle branches > Purkinje fibers

Case Study #2: Pulmonary Valve Stenosis Please use the following case study to answer the remaining quiz questions. Enjoy the case! You are taking care of Carl, a one month old with pulmonary valve stenosis. Pulmonary valve stenosis is a narrowing of the pulmonary valve. You notice Carl is cyanotic (bluish in color), lethargic, and irritable. When you auscultate Carl's heart with a stethoscope, do you expect to hear a murmur?

Yes, I expect there to be a murmur when either AV or SL valves do not function normally. Murmurs result from turbulent blood flow and are heard when any of the 4 heart valves do not function properly.

The tricuspid valve is located:

between right atrium and right ventricle

Remember to imagine that blood in the heart is color-coded according to its oxygenation status (oxygenated blood is red, deoxygenated blood is blue). What color of blood would you expect to see in Isabelle's right ventricle?

both red and blue

Remember that a VSD is located in the interventricular septum. Based on the location of a VSD, what part of the cardiac conduction system might be affected?

both the atrioventricular bundle and the bundle branches

In the heart of a person without a VSD, blood in the right ventricle would be _________, and blood in the left ventricle would be _________.

deoxygenated .... oxygenated

Remember to imagine that blood in the heart is color-coded according to its oxygenation status (oxygenated blood is red, and deoxygenated blood is blue). What color of blood would you expect to see in Isabelle's left ventricle?

red

The wall of a heart chamber thickens, or hypertrophies, when the chamber has to work extra hard to eject blood. Given Carl's pulmonary valve stenosis, which part of his heart may become hypertrophied?

right ventricle Pulmonary valve stenosis narrows the opening between the right ventricle and the pulmonary trunk. Thus, the right ventricle will have to work harder to eject blood into the pulmonary circulation and we expect hypertrophy of the right ventricle if the condition is not treated.

The two valves located on the right side of the heart are the:

tricuspid valve and pulmonary valve

The mitral valve is closed during:

ventricle systole

On an electrocardiogram the QRS complex results from ____________ and the P wave results from ______________.

ventricular depolarization and the P wave results from atrial depolarization.

Blood returns to the heart from the systemic circulation through which blood vessels?

via the inferior vena cava, superior vena cava, coronary sinus.

Tachycardia and bradycardia are respectively defined as heart rate greater than _____ beats per minute (bpm) and heart rate less than _____ bpm.

100 ... 60

Why do you think Carl has cyanosis, or a bluish skin color?

Because it is difficult for Carl's heart to pump blood into the pulmonary circulation, his blood will contain a higher than normal percentage of deoxygenated blood. Deoxygenated blood has a dark red or purplish color, which causes Carl's skin to have a bluish tint.

Case Study #1: Ventricular Septal Defect Here is the case study you will use to answer next set of questions. I hope you enjoy the case! Maria and her newborn daughter Isabelle were discharged from the hospital approximately 5 weeks ago. Maria has noticed that Isabelle is not eating well. Isabelle never seemed to latch well during breast feeding. Two weeks ago Maria switched to bottle feeding with formula. Maria still feels that Isabelle is feeding poorly even after switching to bottle feeding. Isabelle does not feed for very long, and drinks only about 1 ounce at a time. Maria notices that Isabelle seems to breathe heavily all the time, but that her breathing gets even worse after feeding. Maria decides to see a nurse practitioner (NP) in order to discuss her concerns about Isabelle's difficulty feeding and breathing. After listening to Maria's concerns, the NP weighs Isabelle and performs a physical exam. When the NP auscultates Isabelle's chest, she hears a murmur. The NP is concerned both by the murmur, and because Isabelle has not gained much weight since birth. The NP decides to order an ECG and an echocardiogram to evaluate Isabelle's heart. The ECG will show Isabelle's heart rate and rhythm. The echocardiogram (ultrasound of the heart) will provide a picture of Isabelle's heart structure, and show how blood flows through Isabelle's heart. For some of the case study questions you should imagine that blood in the heart is color-coded according to its oxygenation status (oxygenated blood is red, deoxygenated blood is blue). The echocardiogram reveal that Isabelle's murmur is caused by something called a ventricular septal defect (VSD). A VSD is a hole in the interventricular septum, the wall of muscle that separates the left ventricle from the right ventricle. The ECG shows sinus rhythm with no conduction abnormalities. Think about the position of the heart in the chest cavity. Isabelle's VSD is in the interventricular septum between the mitral and tricuspid valves. At what anatomical location would the NP best hear Isabelle's murmur?

Between the right upper sternal border and the left upper sternal border ???