Final answer:
Right-sided heart failure leads to JVD due to the increased pressure in the vena cavae. The impaired pumping action of the right side of the heart causes blood to back up in the veins, including the jugular veins, resulting in their distension.
Step-by-step explanation:
In right-sided heart failure, there is a rise in pressure in the vena cavae and a drop in pressure in the arteries to the lungs. This leads to jugular venous distension (JVD) because of the increased pressure in the vena cavae. The underlying mechanism behind this manifestation is the impaired pumping action of the right side of the heart, which causes blood to back up in the veins, including the jugular veins, resulting in their distension.