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Induction of a reduction in haemoglobin concentration by enalapril in stable, moderate heart failure: a double blind study

Herrlin B, Nyquist O, Sylvén C

British heart journal, 1991

17 participants · 16 citations

Abstract

Objective: To study the long term effects (12 weeks) of enalapril on central haemodynamic function and on arterial oxygen content and its determinants--haemoglobin concentration and oxygen saturation--in patients with stable moderate heart failure.

Design: Double blind placebo controlled randomised study.

Patients: 17 patients with stable moderate heart failure caused by dilated cardiomyopathy which was treated with diuretics and digoxin.

Methods: Central haemodynamic function, arterial oxygen content, arterial haemoglobin concentration, and arterial oxygen saturation were measured at rest and during submaximal exercise. Plasma volume and total body haemoglobin were determined at rest.

Results: With enalapril treatment heart rate, pulmonary capillary wedge pressure, mean arterial pressure, and systemic vascular resistance decreased significantly both at rest and during submaximal exercise. Cardiac output did not change at rest but tended to increase (p = 0.06) during submaximal exercise. Arterial oxygen saturation remained unchanged while haemoglobin concentration and arterial oxygen content were significantly reduced. Total body haemoglobin was significantly reduced but the plasma volume remained unchanged. At rest, the reduction in arterial oxygen content resulted in a significantly reduced mixed venous oxygen content. However, during submaximal exercise the increase in cardiac output fully compensated for the reduction in arterial oxygen content and this effect was…

How strong is the evidence?

Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 3 of 5 (Moderate · trial / cohort / secondary analysis). Trials without a large randomized design, cohorts and secondary analyses give moderate evidence. Reported size: 17 participants or records.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

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