Gradual reactivation over time of vascular tissue angiotensin I to angiotensin II conversion during chronic lisinopril therapy in chronic heart failure

What Was Tested

The paper reports a study of Angiotensin II, published as a randomized controlled trial.

This study was designed to fully characterize vascular tissue angiotensin I (AI)/angiotensin II (AII) conversion changes over time in vivo in humans during chronic angiotensin-converting enzyme (ACE) inhibitor therapy.

Why It Was Studied

Plasma AII does not remain fully suppressed during chronic ACE inhibitor therapy.

However, the plasma renin angiotensin system (RAS) might be dissociated from the vascular tissue RAS.

Who Took Part

The abstract describes 28 patients taking part.

PubMed indexes the participants as middle-aged adults and older adults, both men and women.

A second longitudinal study followed 28 patients with NYHA I to II CHF serially over 18 months to see whether vascular ACE inhibition was progressively lost with time despite ACE inhibitor therapy.

How the Study Was Run

In design terms this was a randomized, double-blind and crossover study.

Random assignment meant chance, not the researchers, decided who got Angiotensin II and who got the comparison, which limits bias.

Blinding on both sides kept the patients and researchers unaware of who received Angiotensin II.

Each person switched between Angiotensin II and the comparison at some point, usually with a gap in between.

The methods mention a period of 18 months.

A cross-sectional study was done to see whether there were differences in vascular AI/AII conversion according to New York Heart Association (NYHA) class.

What Was Measured

Topics PubMed links to this paper include Angiotensin I, Angiotensin II, Angiotensin-Converting Enzyme Inhibitors, Blood Vessels, Chronic Disease, Cross-Sectional Studies and Heart Failure.

What This Means in Plain Language

The paper is a randomized, double-blind and crossover study of Angiotensin II in 28 patients over 18 months.

With fewer than 40 people, it is a small study, so it is better read as an early signal for further research than as a settled answer.

The abstract goes on to report its results in about 6 sentences; this page does not restate them, so read the paper for the findings and their limits.

The publication is from 2002 (Journal of the American College of Cardiology), a journal based in United States.

More context: the Angiotensin II compound page, all human trials.