What Is An ACE Inhibitor?

Question: What is an ACE inhibitor, how does it work, and when is it used to treat heart failure?

Answer: ACE inhibitors are very commonly used medications for varying cardiovascular disorders. It's a great medication for lowering blood pressure, it's used in patients with heart failure, it's used in patients with diabetes and kidney disease.

And the common theme here is that there's a new hormone in the body called angiotensin II which is associated with various forms of vascular disease, progression and development, and because of that, if you use ACE inhibitors to modulate the angiotensin II which is a neurohormone which causes all these disorders, you can have varying benefits like lowering blood pressure and decreasing the risk of kidney disease or stroke.

But when it comes particularly to heart failure, remember there are two different kinds of heart failure. There's a group of patients with heart failure with a poor ventricular function and a weak contraction, and then you have a bunch of patients with heart failure, approximately 50 percent of heart failure out there, are patients who actually have preserved or normal ejection fraction.

There is overwhelming data that the use of ACE inhibitors in patients who have low ejection fraction, leads to all sorts of benefits including reduction in all cause mortality, reducing the risk of hospitalizations, and improving their symptoms.

Now, the data as far as those with heart failure and normal ejection fraction is a little bit more controversial and not necessarily to the depth that we have for low ejection fraction. There's a general consensus that we think it's probably good for those patients, it's certainly good for those patients who have other reasons to use ACE inhibitors like high blood pressure, or diabetes or kidney disease.

But the pure form of heart failure with preserved ejection fraction, we don't necessarily know the answer. There's a cousin of ACE inhibitor or group of drugs called angiotensin receptor blockers and those are being looked at in that patient population, and we'll have definitive answers hopefully pretty soon.