Scenario:
Adapted from Garner and Ree, National Center for Case Study Teaching in Science
Mrs. Helms came in through the front door of her house with an armful of groceries. She put the bag down on the kitchen counter and called to her husband. “Herb, I’m home! Are you ready for lunch?” She didn’t get an answer, so she walked to the living room and found Mr. Helms lying on the floor. “Herb! Are you okay?” she asked as she grabbed his shoulder. Mr. Helms responded weakly while clutching his chest. Mrs. Helms frantically called 911. It only took EMS a few minutes to arrive and the paramedics transported Mr. Helms to the hospital. Upon admission to the hospital, Mr. Helms’ vital signs were recorded as follows:
Mr. Helms Normal
Systolic blood pressure (mm Hg) 90 120
Diastolic blood pressure (mm Hg) 52 80
Oral temperature (°F) 98.9 97.8-99.1
Heart rate (beats per minute) 120, irregular 60-80
Respiratory rate 33, labored 12-20
Oxygen saturation (amount of O2 in arterial blood) 89% 95-100%
Mr. Helms was admitted to the hospital with chest pains and shortness of breath. His wife was panicked since her 72 year-old husband had a history of heart disease and had a heart attack two years ago. The admitting physician suspected another heart attack and ordered an echocardiogram. After examination and an echocardiogram, Dr. Collins spoke with Mrs. Helms. “I’m very sorry, but your husband has had another heart attack resulting in valve failure. The heart attack was caused by an occlusion in an artery that provides the heart muscle with blood. Lack of blood flow to the area damaged the papillary muscle that controls a valve in his heart has been severely damaged and is no longer working.”
Questions
- What is the function of the papillary muscle and how does it affect heart valve function?
- Which valve is affected with damage to the papillary muscle in the left ventricle?
- Based on your knowledge of cardiac circulation, which artery is probably occluded to cause damage to the papillary muscle in the left ventricle.
- Why is Mr. Helms’ respiratory rate and oxygen saturation altered?
- Why is Mr. Helms’ heart rate so high?does Mr. Helms’ have high blood pressure? Explain.