Final answer:
Infrared therapy is contraindicated in cardiovascular insufficiency because the additional heat can strain an already compromised cardiovascular system.
Step-by-step explanation:
Infrared therapy is contraindicated in conditions where the application of heat could exacerbate the illness or symptoms. Considering the options provided, cardiovascular insufficiency is a condition in which infrared therapy could potentially worsen the patient's health status. In patients with cardiovascular insufficiency, the body is already struggling to manage blood flow and cardiac output, and the addition of heat from infrared therapy could put additional strain on the cardiovascular system, possibly leading to more serious complications.