Advanced Patient Assessment Practice Exam

Which of the following physiological effects is associated with myocardial infarction?

1. Increased cardiac output

2. Arterial hypertension

3. Good blood flow to the brain

4. Backup of blood into the lungs

The correct answer is: Backup of blood into the lungs

In the context of myocardial infarction, a backup of blood into the lungs is a significant physiological effect that occurs as a result of the heart's compromised ability to pump effectively. When a myocardial infarction happens, heart muscle is damaged, often leading to impaired contractility and reduced cardiac output. This inefficiency causes pressures to build up in the heart and subsequently in the pulmonary circulation, resulting in pulmonary congestion and symptoms such as dyspnea and cough. The heart's inability to manage the return of blood from the body effectively leads to a scenario where blood backs up into the lungs, causing fluid to leak into the interstitial spaces of lung tissue. This can manifest as pulmonary edema, significantly impacting gas exchange and leading to respiratory distress. While other options presented may have some relevance under certain conditions, they do not directly relate to the typical physiological response observed during a myocardial infarction. Increased cardiac output typically does not occur, and arterial hypertension may not be a defining factor, especially if the heart is significantly weakened. Additionally, the notion of good blood flow to the brain can be misleading since, during an acute event like a myocardial infarction, overall perfusion may be compromised, affecting cerebral circulation as well.