Final answer:
The compensatory mechanism involved in HF that leads to inappropriate fluid retention and additional workload of the heart is the neurohormonal response.
Step-by-step explanation:
The compensatory mechanism involved in heart failure (HF) that leads to inappropriate fluid retention and additional workload of the heart is the neurohormonal response.
During heart failure, the body's neurohormonal response is activated, including the release of hormones like angiotensin II and aldosterone. Angiotensin II stimulates aldosterone release, causing the collecting duct to retain sodium and water, leading to fluid retention. This places additional workload on the heart and contributes to the symptoms and progression of heart failure.