Are Angiotensin-II Antagonists Effective in CHF Treatment?
Activation of the renin-angiotensin system in patients with congestive heart failure (CHF) leads to vasoconstriction and retention of sodium and water. These patients are often treated with angiotensin-converting enzyme (ACE) inhibitors, which inhibit the production of angiotensin II. Despite the known benefits of treatment with ACE inhibitors, morbidity and mortality rates remain unacceptably high in these patients. The hemodynamic and clinical benefits of ACE inhibitors may be limited by enzymes that are resistant to ACE inhibition. Treatment with a newer angiotensin-II antagonist has been shown to provide a more complete blockade of the renin-angiotensin system and to avoid some of the side effects associated with ACE inhibitors. Havranek and colleagues evaluated the effectiveness of irbesartan in reducing pulmonary capillary wedge pressure in patients with heart failure. In addition, the drug was evaluated for acute and long-term hemodynamic effects, safety and clinical effects. Ad