Elsevier

The Lancet

Volume 351, Issue 9095, 3 January 1998, Pages 9-13
The Lancet

Articles
Biochemical detection of left-ventricular systolic dysfunction

https://doi.org/10.1016/S0140-6736(97)03034-1Get rights and content

Summary

Background

In previous studies on the use of natriuretic peptides to detect left-ventricular systolic dysfunction, a higher rate of cardiac disorders in the control groups than in the study groups could have led to bias. We investigated the effectiveness of plasma N-terminal atrial natriuretic peptide (NT-ANP) and brain natriuretic peptide (BNP) concentrations to show left-ventricular systolic dysfunction in a random sample of the general population.

Methods

We randomly selected 2000 participants aged 25–74 years from family physicians' lists in Glasgow, UK. We sent all participants questionnaires. 1653 respondents underwent echocardiography and electrocardiography. We took a left-ventricular ejection fraction of 30% or less to show left-ventricular systolic dysfunction. NT-ANP and BNP were measured in plasma by RIAs.

Findings

1252 participants had analysable electrocardiograms and echocardiograms, completed questionnaires, and available blood samples. Median concentrations of NT-ANP and BNP were significantly higher in participants with left-ventricular systolic dysfunction (2·8 ng/mL [IQR 1·8–4·6] and 24·0 pg/mL [18·0–33·0]) than in those without (1·3 ng/mL [0·9–1·8] and 7·7 pg/mL [3·4–13·0]; each p<0·001). Among participants with left-ventricular systolic dysfunction, both symptomatic and asymptomatic subgroups had raised NT-ANP and BNP concentrations. A BNP concentration of 17·9 pg/mL or more gave a sensitivity of 77% and specificity of 87% in all participants, and 92% and 72% in participants aged 55 years or older.

Interpretation

Measurement of BNP could be a cost-effective method of screening for left-ventricular systolic dysfunction in the general population, especially if its use were targeted to individuals at high risk.

Introduction

Chronic heart failure (CHF) is a common, disabling disorder with high mortality, which is mainly attributable to left-ventricular systolic dysfunction.1, 2 CHF is often the endstage of progressive deterioration of left-ventricular function, which can remain asymptomatic for many years. The asymptomatic form of left-ventricular systolic dysfunction is as common as CHF.3 Treatment with inhibitors of angiotensin-converting enzyme decreases mortality and morbidity in patients with left-ventricular systolic dysfunction, with or without symptoms,4, 5 so detection of the disorder is worthwhile.

Detection of patients with symptomatic and asymptomatic left-ventricular systolic is crucial to decrease the substantial mortality and morbidity associated with CHF. However, the clinical diagnosis of CHF is unreliable6 and the asymptomatic precursor is clinically undetectable. Although population screening with echocardiography might provide a solution, it would not be cost-effective and a biochemical option would be more attractive.

C-terminal and N-terminal atrial natriuretic peptides (CT-ANP and NT-ANP) are mainly secreted by the atria in response to the stretch that occurs with the increased left-atrial pressure associated with CHF.7 The circulating concentrations of these peptides are raised in patients with symptomatic left-ventricular systolic dysfunction,8, 9 and the higher concentrations of NT-ANP reflect its longer half-life, which is due to lower renal clearance.10 Plasma concentrations of brain natriuretic peptide (BNP) mainly produced by the ventricles—are also raised in patients with symptomatic left-ventricular systolic dysfunction.11, 12 Moreover, plasma concentrations of both peptides are also raised in patients with asymptomatic left-ventricular systolic dysfunction.9, 12 Population screening for left-ventricular systolic dysfunction with natriuretic peptides has not been studied. We investigated the usefulness of NT-ANP and BNP in the identification of left-ventricular systolic dysfunction as a method of screening in the general population.

Section snippets

Methods

We randomly selected 2000 people aged 25–74 years from North Glasgow, UK, who had participated in the Third Glasgow MONICA risk factor survey in 1992. We used a two-stage random-sampling procedure. First, we randomly selected 30 family physicians from the 210 in the area. Second, we randomly selected patients of both sexes in 10-year age-groups between 25 and 74 years, in proportion to the age and sex distribution of the doctor's list of patients. We sent questionnaires to all patients; we

Results

Table 1 shows the characteristics of the study population. 1252 participants had an analysable echocardiogram, a completed questionnaire, an electrocardiogram, and an available blood sample.

37 participants (3·0%) had left-ventricular systolic dysfunction (left-ventricular ejection fraction ⩽30%); the impairment was symptomatic (cardiac dyspnoea or loop diuretic treatment) in 18 and asymptomatic in 19.

The median concentration of NT-ANP was significantly higher in participants with

Discussion

We have confirmed that BNP and NT-ANP are raised in people with left-ventricular systolic dysfunction, whether symptomatic or asymptomatic. Raised concentrations of BNP and NT-ANP have been reported previously in studies of patients with left-ventricular systolic dysfunction, especially previous myocardial infarction. However, we have now shown that people with asymptomatic left-ventricular systolic dysfunction, sampled from the general population have high circulating concentrations of

References (26)

  • JA Sundsfjord et al.

    Identification and plasma concentrations of the N-terminal fragment of proatrial natriuretic factor in man

    J Clin Endocrinol Metab

    (1988)
  • CH Wei et al.

    Natriuretic peptide system in human heart failure

    Circulation

    (1993)
  • NB Schiller et al.

    Left ventricular volume from paired biplane ventriculography

    Circulation

    (1979)
  • Cited by (917)

    View all citing articles on Scopus
    View full text