Page 1“Th e Heart of the Problem” by Garner and Ree
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Part I – Emergency 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 fl oor. “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 to 99.1 Heart rate (beats per minute) 120, irregular 60–80 Respiratory rate (breaths per minute) 33, labored 12 to 20 Oxygen saturation 89% 95–100%
Questions 1. Which of Mr. Helms’ vital signs and lab values were abnormal?
2. What additional medical tests would you order for Mr. Helms? In other words, what other information would be useful?
From Heart Attack to Kidney FailureFrom Heart Attack to Kidney Failure by Kristine A. Garner and Brandy C. Ree Department of Biological Sciences University of Arkansas – Fort Smith
The Heart of the Problem:The Heart of the Problem:
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Part II – Cardiac Involvement 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. 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. A papillary muscle that controls a valve in his heart has been severely damaged and is no longer working.”
Questions 1. What is the purpose of blood fl ow?
2. Describe blood fl ow through the heart starting with blood entering the right side of the heart and including all chambers and valves.
3. What is the function of heart valves?
4. What is the function of papillary muscles?
5. Which valve is aff ected with damage to the papillary muscle in the left ventricle?
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Part III – Cardiovascular Involvement Dr. Collins called Nurse Nan from the patient’s room and confi ded, “Mr. Helms is in bad shape. His left posteromedial papillary muscle was damaged from his heart attack. Th e papillary muscle is no longer able to maintain closure of the valve, and this has resulted in mitral valve prolapse. With decreasing cardiac output, this patient is in for a fi ght for his life.” Nurse Nan knew that maintaining cardiac output was necessary for adequate blood fl ow through the body. As Dr. Collins walked away, Nurse Nan composed herself to tell Mrs. Helms the bad news and returned to the patient’s room. Nurse Nan explained to Mrs. Helms that her husband had left-sided heart failure and that his blood pressure was slowly and steadily decreasing.
Questions 1. In general, how is the direction of blood fl ow disrupted because of mitral valve prolapse?
2. Does the mitral valve prolapse increase, decrease, or not change stroke volume (the amount of blood exiting the ventricle with each ventricular contraction)?
3. How does mitral valve prolapse decrease cardiac output (the amount of blood exiting the ventricle per minute)?
4. Explain how cardiac output determines blood pressure.
5. Why is Mr. Helms’ heart rate higher than normal?
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Part IV – Pulmonary Involvement Mrs. Helms was very upset with the news of her husband’s condition. As the day progressed, she noticed that Mr. Helm’s breathing was increasingly diffi cult. He could barely speak without losing his breath. Mrs. Helms called the nurse to her husband’s room. “My husband can’t breathe! What is wrong? I thought he had a heart attack not a respiratory condition!” Nurse Nan auscultated the patient’s chest listening to Mr. Helms’ respirations, which were rapid and wet, producing rales or crackling sounds. Nurse Nan calmly informed Mrs. Helms, “I’m sorry. Your husband’s condition is worsening. Th e damage to his heart is causing his respiratory problems.”
Questions 1. Th e left side of the heart receives blood from which part of the body?
2. If the bicuspid (mitral) valve is not fully closing, does pulmonary circulation increase, decrease, or not change?
3. Does pulmonary blood pressure increase or decrease with left-sided heart failure? Explain.
4. Does this change in pulmonary blood pressure increase or decrease capillary fi ltration in the lungs? Explain.
5. How does change in pulmonary blood pressure and capillary fi ltration cause Mr. Helms’ rales (wet breath sounds)?
6. Why is Mr. Helms breathing rapidly?
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Part V – Renal Involvement Th e next morning when Nurse Nan started her shift, she immediately checked on Mr. Helms. His cardiovascular and respiratory conditions were still deteriorating, but Nurse Nan discovered something new. Mr. Helms’ urine output was almost nonexistent. Nurse Nan informed Dr. Collins, who was gravely concerned. Dr. Collins met with Mrs. Helms to tell her that her husband could not survive kidney failure. Mrs. Helms looked shocked. She then became very upset and angry. “What did you do, Dr. Collins? My husband had a heart attack, but his kidneys were fi ne; he’s never had a kidney problem! How could you let this happen?” Nurse Nan put her arm around Mrs. Helms’ shoulders and Dr. Collins handed her a tissue. Dr. Collins explained, “Th e damage to your husband’s heart is very serious. Th e kidneys rely on blood pressure to work and his heart failure is causing the kidney failure.”
Questions 1. What are the functions of the kidneys?
2. What is the force that causes the fi ltration of the blood by capillaries in the kidneys to occur?
3. Does left-sided heart failure increase, decrease, or not aff ect kidney fi ltration? Explain.
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Case copyright held by the National Center for Case Study Teaching in Science, University at Buff alo, State University of New York. Originally published December 8, 2015. Please see our usage guidelines, which outline our policy concerning permissible reproduction of this work. Licensed photo in title block © Win Nondakowit | Fotolia, id 67898135.
Part VI – Resolution Dr. Collins rushed Mr. Helms into surgery for valve replacement. Mrs. Helms waited anxiously in the waiting area for family for hours until she saw Nurse Nan coming toward her with a big smile. “Your husband is in the recovery room. He’s going to be just fi ne.” Mrs. Helms sighed with relief and gave Nurse Nan a big hug.
Questions 1. How would you expect Mr. Helms’ vital signs and respiratory and kidney functions to change after valve
replacement surgery? Explain.
2. Now that you are familiar with left-sided heart failure, describe blood fl ow with right-sided heart failure.
3. What are some possible causes of right-sided heart failure?
4. What symptoms could be expected with right-sided heart failure?
