Question

Pathophysiology Assignment 2 Chapter 32, Disorders of Cardiac Function Juana had just finished lunch with her husband, and they had just prepared to watch television. She is 75 years old and has had a history of angina. Shortly after they sat down, Juana said she had indigestion and went to take some antacid tablets. An hour later, she began to feel warm, restless, and anxious. Her husband noticed she was looking pale and said he would take her to a nearby walk-in clinic. By the time they arrived, Juana said her left arm and shoulder were sore. Suspecting Juana was having a heart attack, her husband turned the car around and rushed her to the hospital. Three hours after the onset of her symptoms, Juana was receiving oxygen, fibrinolytic therapy, and nitroglycerin in the emergency ward. Afterward, she was moved to the cardiac unit for STEMI. (Learning Objectives: 5 and 6) An ECG of Juana's heart demonstrated an elevated ST segment. What are the physiological effects of myocardial ischemia that produce this finding? What variables affect the ECG tracing of a patient with ACs? I. What are the benefits of administering fibrinolytic therapy, nitroglycerin, and oxygen in the early management of STEMI? 2. What is the inflammatory response in the postinfarction recovery period? Why will Juana's heart function be compromised after her STEMI? 3.

Answer 1

1 The classic. Ecg changes that occur with an MI are seen in the leads that viewthe involved surface of the heart.The classic Ecg changes are T-Wave inversion ,ST-segment elevation and development of an abnormal Q wave.Because infarction evolves over time ,the Ecg also changes over time.The first Ecg signs of an acute MI occurs as a result of myocardial ischaemia and injury..Myocardial injury causes the T wave to become enlarged and symmetric.As the area of injury becomes ischaemic,myocardial repolarization is altered and delayed,causing the T wave to invert.The ischaemic region may remain depolarized while adjacent areas of the myocardium return to the resting state.Myocardial injury also causesST segment changes.

3 Fibriniolytics dissolve clots by converting plasminogen into plasmin.Nitroglycerin decreases the worklad of the heart by reducing venous return to the heart.

4 During the healing process in post infarction recovery period ,inflammation is a cornerstone .Neutrophils accumulate between 18-48 hrs post-occlusion-chemotactic factors include complement fragments and arachidonic acid metabolites.Macrophages are resent from 2 days to 4-6 weeks.Endothelia cells up-regulate leukocyte adesion molecules P-selectin,E-selectin and ICAM-1