Ongoing trials involving angiotensin-converting enzyme inhibitors

Angiotensin-converting enzyme inhibitors (ACEIs) are an important class of drugs in cardiovascular disease. As their name suggests, they act by blocking angiotensin converting enzyme, thereby limiting the production of angiotensin II, the most active component of the renin-angiotensin-aldosterone system. This system plays an important role in maintenance of blood pressure and electrolyte and fluid balance. Therefore, by blocking this system, the ACEIs have wide ranging effects. Recent trials have reaffirmed their place in the management of hypertension, congestive cardiac failure, in the prevention of renal complications in diabetes and the prevention of strokes in 'at risk' patients. There are still many ongoing trials using the ACEIs. These trials are mainly aimed at comparing their efficacy with 'older' drugs (such as β-blockers) and 'newer' drugs such as the angiotensin receptor blockers and calcium antagonists in different indications, such as heart failure and diabetic nephropathy. The impact of these drugs on the prevention of macro- and micro vascular complications in diabetes is also being investigated. The results of all these trials, when available, are expected to reaffirm the important role of this class of drugs in our modern day medical armamentarium. In this review, the ongoing clinical trials involving ACEIs, the rationale behind these trials and what impact they hope to have on our current understanding of the role of this important class of drug in medical practice, will be discussed.