Biol 1120

Cardiovascular Case Study

Name ______

A 32-year old nurse who has rheumatic fever as a child noticed a persistent tachycardia and light-headedness. Upon examination, chest x rays showed an enlarged left atrium and left ventricle. ECG analysis showed atrial fibrillation. There was also mild pulmonary congestion. Cardiac evaluation resulted in the following information:

Cardiac output (CO) 3.2L/min. SV = 40mls

Blood pressure (BP) 100/58 mm Hg

Left Atrial pressure (LAP) 16 mm Hg

Right ventricular pressure (RVP) 44/8 mm Hg

Heart sounds revealed valvular regurgitation

1. Answer all questions with material that explains your answer. Yes/no answers receive NO credit.

2. Submit this as a hard copy double spaced typed paper.

3. Total possible 25points

  1. Based on the information provided, which A-V valve is incompetent? Why did you choose this set of valves? What is this condition called? (3pts)

Due to the enlarged nature of the left atrium and left ventricle I would say that the problem is occurring within the left atrioventricular (bicuspid) valve. I would choose the bicuspid valve because the woman is presenting symptoms of valvular regurgitation, meaning that the valve is not closing all the way. Because the valve is not able to close, backflow of blood can not be completely avoided. This is also what is causing the mild pulmonary congestion, meaning that blood is not being properly or regularly removed from the lungs, as well as the enlarge nature of the left side of the heart. The condition the nurse has is called rheumatic heart disease because the rheumatic fever she had when she was younger likely caused damage to her bicuspid valve.

  1. Which heart sound would be pronounced and lengthened?Explain why they sound this way(3pts).

The Lub Dub noise coming from the heart is the sound of the heart valves closing. sound would be pronounced and lengthened due to the insufficient opening and closing of the bicuspid valve.

  1. Describe, using surface anatomy, the location at which this valvular disorder could best be heard. (2pts)

The disorder would best be heard at the apex of the heart. Here, you would be able to hear the drawn out lub noise of the the AV valve attempting to close because is it nearest to the left atrium and ventricles.

4. Draw a normal EKG, label and explain what the deflections wave mean. (2pts. ) Do you expect to see a normal EKG for this patient? What will it look like? ( 3 points)

If this woman is experiencing atrial fibrillation and the contractions are not, then her EKG would be extremely erratic.

P Wave: Atrial depolarization

QRS Complex: ventricular depolarization, atrial relaxation

T wave: ventricular repolarization

5. Considering the medical problem that this patient is experiencing, what are the causes of 1. tachycardia, 2. light-headedness, and 3. mild pulmonary congestion? ( 6pts, address each one)

Tachycardia: the tachycardia would most likely be caused by the atrial fibrillation. The intrinsic conduction system is being thrown off, meaning the pacemaker (SA node) is not able to regulate the pace at which the heart is beating.

Light headedness: Would likely be caused by insufficient blood circulation to the brain. Because of the mild pulmonary congestion, oxygenated blood is flowing less sufficiently than normal. As blood flows into the left atrium, the bicuspid valve damage doesn’t allow for sufficient flow of oxygenated blood into the left ventricle and therefore less blood is able to travel through the left semilunar valve and up into the aorta to the rest of the body (including the head).

Mild Pulmonary Congestion: Likely cause is the backflow of blood in the bicuspid valve. Normally, when blood flows back into the heart through the pulmonary veins coming from the lungs, the AV valves will open in order to allow the ventricles to fill with blood. Then, as the ventricles contract, the AV valves should close in order to allow blood to be pushed into the major vessels and prevent any backflow. In the patients case, the damaged valve is not performing correctly and causing backflow and decreased cardiac output.

7. site your references (1pts)

"Rheumatic Heart Disease." Emedicine.medscape.com. N.p., n.d. Web. <

McKinely, Michael P., and Valerie Dean O'Loughlin. Anatomy & Physiology: An Integrative Approach. N.p.: Mcgraw Hill, 2013. Print.