How does benazepril treat congestive heart failure?

Benazepril (an angiotensin-converting enzyme inhibitor -- or ACE inhibitor, also sold under the brand name, Lotensin) works to treat congestive heart failure as follows: 

• Benazepril blocks the enzyme responsible for production of angiotensin II --  a substance that causes arteries to constrict, resulting in high blood pressure.  
• By decreasing the rate of angiotensin II formation, benazepril relaxes arteries, lowers blood pressure and improves cardiac output.

Lotensin HCT combines benazepril and hydrochlorothiazide, a diuretic. Although generally used for later stages of high blood pressure, some doctors prescribe Lotensin HCT to treat congestive heart failure.