Which acute condition could lead to dyspnea on exertion?

Dyspnea on exertion can be a significant symptom associated with various acute conditions, but pleural effusion is particularly notable in this context. Pleural effusion refers to the accumulation of excess fluid in the pleural space surrounding the lungs. This buildup can restrict lung expansion and decrease lung compliance, leading to difficulty in breathing, especially during physical activity or exertion.

When a pleural effusion occurs acutely, the increased pressure from the fluid can lead to a reduced ability of the lung to expand fully. As a result, even mild physical exertion may cause significant breathlessness due to reduced lung capacity and impaired gas exchange. In patients with a substantial pleural effusion, symptoms such as dyspnea can become more pronounced as the demand for oxygen increases during activity.

The other conditions listed also contribute to dyspnea but are more often chronic in nature or have different pathophysiological processes that lead to exertional dyspnea. Chronic obstructive pulmonary disease (COPD) often results in dyspnea over time due to progressive airflow obstruction and is typically not an acute condition. Myocardial infarction, while it can cause dyspnea, usually presents with more classic signs such as chest pain and would not specifically lead to