A 66-year-old man arrives at the hospital after hours of severe chest pain. What follows allows us to trace the physiology of a myocardial infarction step by step.

We examine atherosclerosis, coronary artery obstruction, electrocardiographic changes, myocardial injury, cardiogenic shock, and mechanical complications. This clinical case illustrates why time can profoundly influence the outcome of a heart attack.

Sources and further reading:

1. Ribeiro WN, Yamada AT, Benvenuti LA. Case 4/2014: a 66-year-old man with acute myocardial infarction and death in asystole after primary coronary angioplasty. Arq Bras Cardiol. 2014;103(3):e31-e36. doi:10.5935/abc.20140129.
2. Thygesen K, Alpert JS, Jaffe AS, et al. Fourth universal definition of myocardial infarction (2018). J Am Coll Cardiol. 2018;72(18):2231-2264. doi:10.1016/j.jacc.2018.08.1038.

Educational content only. Not a substitute for individualized medical advice, diagnosis, or treatment.

How does the body remain stable while everything around us changes?

We explore homeostasis and the sensors, control centers, and effectors that regulate variables such as temperature, blood glucose, and blood pressure. We also explain negative feedback and amplifying feedback mechanisms, showing how the body constantly responds, corrects, and adapts.

Sources and further reading:

1. Kiesewetter A, Schmiemann P. Understanding homeostatic regulation: the role of relationships and conditions in feedback loop reasoning. CBE Life Sci Educ. 2022;21(3):ar56. doi:10.1187/cbe.21-04-0092.
2. Hall JE, Hall ME. Guyton and Hall textbook of medical physiology. 14th ed. Philadelphia: Elsevier; 2020.

Educational content only. Not a substitute for individualized medical advice, diagnosis, or treatment.