How do ACE inhibitors help with chf?

ACE-I. Reduces the resistance against which the failing heart has to pump, reduces the internal renin angiotensin aldosterone hormones that are increased with heart failure and can cause more problems, thus reduces the mortality of heart failure.
They ease work load. They lower the amount of work that the heart has to do by lowering resistance to blood flow out of the heart. This is called unloading the heart. It's like a water pump pumping downhill instead of up hill; less work.

Related Questions

One of symptom of CHF is cough, can ACE inhibitors be used as it also causes cough.

CHF. Treatment of congestive heart failure is complex. One of the most important medications is an ace inhibitor to improve the cardiac function. Although there is a potential side effect of a dry cough in a small percentage of patients using an acei, the benefit far outweighs the risk and it should be a first line medication. Speak with your cardiologist for details of dosing. Read more...
Yes. Cough due to CHF is due to excessive fluid buildup in lungs due to inefficient heart function. Cough due to ace inhibitors is a benign (though irritating) side effect seen in a minority of patients. Ace inhibitors are first line drugs for "systolic" CHF ( due to weakened heart muscle). Presence of cough does not exclude use, but most physicians would switch to alternative "arb" medication. Read more...

What can be prescribed in place of ACE inhibitors due to allergy? This is for chf

ARBs,CCBs. Angiotensin receptor antagonists or calcium channel blocker(amlodipine). The issue with the ace inhib.Is a bit complex. If one is prone to angioedema (deep tissue swellings), an ace inhibitor can occ. Seem to bring out the tendency. If one is prone to a cough this med can confuse the picture. Debate exists about ace lnh. In those with allergy shots. Ace inh., per se, isn't a problem in allergy. Read more...
ARBs. I presume for allergy you refer to a chronic cough? If so, a different class of medications can be used. They are referred to arbs. Losartan is an example. Read more...