Angiotensin II blockade in congestive heart failure

Area of Science:

• Cardiology
• Pharmacology

Background:

• Congestive heart failure (CHF) is often associated with elevated systemic vascular resistance.
• The renin-angiotensin system plays a role in regulating vascular tone and blood pressure.

Purpose of the Study:

• To investigate the effects of angiotensin II antagonism using saralasin in patients with congestive heart failure.
• To determine if saralasin can reduce elevated systemic vascular resistance in CHF patients.

Main Methods:

• Infusion of saralasin, a specific angiotensin II antagonist, in normotensive patients with CHF.
• Measurement of systemic vascular resistance, left ventricular filling pressure, cardiac index, and mean arterial pressure before and after saralasin infusion.
• Comparison of responses in CHF patients and healthy controls.

Main Results:

• Five of 11 CHF patients showed a significant reduction in systemic vascular resistance (from 2274 to 1690 dynes/sec/cm-5) after saralasin infusion.
• Responders experienced decreased left ventricular filling pressure, increased cardiac index, and reduced mean arterial pressure.
• Non-responders and controls showed no significant change or a slight increase in systemic vascular resistance.
• Plasma renin activity did not predict response to saralasin.

Conclusions:

• Specific inhibition of angiotensin II with saralasin can effectively reduce systemic vascular resistance in a subset of patients with congestive heart failure.
• Angiotensin II antagonism represents a potential therapeutic strategy for managing elevated peripheral resistance in certain CHF patients.