From kinetics to dynamics: are there differences between ACE inhibitors?

Angiotensin converting enzyme inhibitors are established treatment for hypertension and heart failure. There are well documented differences between ACE inhibitors both in physicochemical properties and pharmacokinetics. Pharmacodynamic actions are similar for most members of the ACE inhibitor class but there are compounds with additional effects which may reflect protease inhibition or non-enzyme-directed pharmacological properties. Clinically relevant differences are few and far between, particularly in the treatment of hypertension when the optimal dose and dose intervals are used. In heart failure there may be a role for drugs with additional properties such as neutral endopeptidase inhibition. In addition, ACE inhibitors differ in the profile of blood pressure changes after the first dose. Early haemodynamic changes with a fall in blood pressure in heart failure patients may be disadvantageous in terms of subsequent outcome. Thus the haemodynamic effects of the first dose may be relevant to the choice of ACE inhibitors in heart failure.