Prolonged immobility can lead to which cardiovascular changes?

• A. Increased venous return with orthostatic hypertension.
• B. Reduced venous return with orthostatic hypotension, increased risk of DVT/PE, decreased cardiac output, and deconditioning.
• C. No cardiovascular changes occur.
• D. Enhanced venous return with improved cardiac output.

Answer: (B)

Prolonged immobility reduces the muscle pumping action that helps push blood back to the heart, so blood tends to pool in the legs. This lowers venous return to the heart, which in turn reduces stroke volume and cardiac output. The reduced circulating volume and weakened autonomic responses also make standing more likely to cause orthostatic hypotension. Venous stasis boosts the risk of blood clots forming in the legs (deep vein thrombosis), and if a clot travels to the lungs it can cause a pulmonary embolism. Over time, the cardiovascular system becomes deconditioned, leading to less efficient heart function and lower overall cardiac performance.

This option best matches the expected changes with immobility, whereas increased venous return, no changes, or enhanced return with improved output do not fit the physiological effects of prolonged inactivity.