Cohort study of plasma natriuretic peptides for identifying left ventricular systolic dysfunction in primary care.

OBJECTIVES: To determine whether blood natriuretic peptide concentrations are helpful in identifying or excluding left ventricular systolic dysfunction in stable survivors of acute myocardial infarction. DESIGN: Comparison of blood natriuretic peptide concentrations with echocardiographic assessment of left ventricular systolic function in a general practice population. SETTING: Practices in Western District of Glasgow audit group. SUBJECTS: 134 long term survivors of myocardial infarction recalled for echocardiography as part of a primary care secondary prevention audit. MAIN OUTCOME MEASURES: Area under the receiver operating curve for brain natriuretic peptide and N-terminal atrial natriuretic peptide. RESULTS: Brain natriuretic peptide was of some diagnostic utility in identifying the minority of subjects with severe left ventricular dysfunction (area under curve=0.73) but was unable to discriminate between patients with moderately severe dysfunction and those with preserved left ventricular function (area under curve for moderate or severe dysfunction=0.54). The corresponding values for N-terminal atrial natriuretic peptide for severe and moderate or severe dysfunction were 0.55 and 0.56 respectively. CONCLUSIONS: Blood natriuretic peptide concentrations are not useful in identifying important left ventricular systolic dysfunction in stable survivors of myocardial infarction.

The laboratory assessment of a new fabric for reducing bacterial penetration of operating theatre apparel.

A one-piece experimental suit was made up from Gore-Tex fabric and assessed in an environmental chamber using 20 male volunteers with respect to reducing airborne contamination. Comparison was made with a similar cotton suit, a two piece short-sleeved cotton suit (blues) and "Y-front' underpants (briefs). The Gore Tex suit produced a reduction in contamination (with 95 per cent confidence limits) of 85.9 +/- 5.9 per cent over the cotton suit and over the blues and briefs at similar levels. Scanning electron microscopy showed that bacterial penetration would not occur.

Dinamap arm and thigh arterial pressure measurement.

Two automatic arterial pressure monitors (Model 1846 P) were used in 30 patients to measure arterial pressures and heart rates in the thigh and arm. Significant differences were found in thigh-arm systolic (p less than 0.001) and diastolic pressures (p less than 0.05). Arm pressures could be predicted from leg pressures and correction factors are suggested. Mean pressures in the thigh approximated more closely to the calculated mean pressures than in the arm. These differences were of little clinical importance.