Final answer:
ACE inhibitors are used to block the conversion of angiotensin I to angiotensin II in patients with congestive heart failure. Examples of ACE inhibitors include Candesartan (Atacand), Irbesartan (Avapro), and Telmisartan (Micardis).
Step-by-step explanation:
The drug used to block the conversion of angiotensin I to angiotensin II in patients with congestive heart failure is an ACE inhibitor. ACE inhibitors, or angiotensin converting enzyme inhibitors, block the ACE enzyme from converting angiotensin I to angiotensin II, which helps to lower blood pressure and reduce the workload on the heart. Examples of ACE inhibitors include Candesartan (Atacand), Irbesartan (Avapro), and Telmisartan (Micardis).