No abstract

Atrial natriuretic factor (ANF) is a peptide hormone secreted by the heart that is degraded in vivo by endopeptidase 24:11 (atriopeptidase). UK 69,578 is a novel atriopeptidase inhibitor that raises plasma levels of ANF in animals and normal volunteers, with associated diuresis and natriuresis. This study examines the effects of UK 69,578 in patients with mild heart failure. UK 69,578 was administered as an intravenous infusion over 20 min in a placebo-controlled, cross-over study to six patients with stable (NYHA Class 2) chronic heart failure. The atriopeptidase inhibitor was well tolerated and no side effects were encountered. Mean baseline plasma ANF was elevated at 88 pg/mL (normal less than 50), and increased 2- to 5-fold after UK 69,578 administration. Plasma ANF did not change significantly following placebo. There was a marked diuresis after UK 69,578 compared to placebo. Urinary sodium excretion doubled for 4 to 6 h, but there was no significant rise in potassium excretion. There was no increase in plasma active renin concentration during the study period. Noninvasive hemodynamic monitoring revealed no significant changes in heart rate, systemic arterial blood pressure, or echocardiographic left ventricular dimensions. However, invasive measurements using a Swan-Ganz catheter demonstrated falls in mean right atrial and pulmonary artery wedge pressures after UK 69,578. There was no change in cardiac output. Thus, inhibition of endopeptidase 24:11 by UK 69,578 results in significant elevation of plasma ANF, with associated diuresis, natriuresis and venodilatation. The compound was well tolerated in these patients with mild chronic heart failure.

The effect of simvastatin in 27 patients with severe primary hypercholesterolaemia was assessed by a double-blind placebo controlled parallel group trial. Total serum cholesterol, LDL-cholesterol and apoprotein B (ApoB) were significantly reduced by simvastatin 40 mg daily. Reductions in triglyceride and VLDL-cholesterol and an increase in HDLcholesterol levels were only significant when calculated as a percentage of baseline, because of wide inter-individual variability. No changes in apoprotein Al, lipoprotein (a), fibrinogen, viscosity or blood pressure were observed. Leucocyte HMG-CoA reductase activity was unchanged after 4 weeks of active treatment but increased by 87% after 3 months (n = 21, P < 0.05). No severe adverse effects or changes in CK or AST levels were noted. We conclude that simvastatin is effective in the treatment of severe and resistant hypercholesterolaemia, and well tolerated in the short term.

Forty patients with a recently healed duodenal ulcer (DU) that presented with haemorrhage were entered into a blind, randomized study of maintenance ranitidine therapy (150 mg at night) versus a placebo preparation, to determine whether prolonged ranitidine therapy could influence the natural history of the ulcer diathesis. Duodenal ulceration or duodenal cap erosions of Lanza grade 3 recurred in 24 of the 40 patients studied during the 2-year trial period but was associated with further bleeding in only 2 cases. Maintenance ranitidine therapy significantly reduced the incidence and symptoms of DU/erosion recurrence at all time intervals beyond 3 months, the maximum protective effect being observed after 12 to 15 months of treatment (incidence, p less than 0.001; symptoms, p less than 0.03). The DU/erosion recurrence rate without treatment after 2 years of successful maintenance ranitidine therapy was significantly less than for patients randomized to the placebo group at entry to the study (p less than 0.03). Two years of maintenance ranitidine therapy appear to be beneficial for patients who have a healed DU that presented with haemorrhage. This treatment, however, cannot be recommended without reservation until the implications of the associated high incidence of asymptomatic duodenal ulceration have been fully evaluated.

SUMMARY Forty patients who were managed conservatively after haemorrhage from an endoscopically verified duodenal ulcer were randomised at discharge from hospital to enter a blind study of ranitidine therapy (150 mg bd) versus a placebo tablet. The patients were reendoscoped after four weeks, ulcer status defined and the trial code broken revealing that five of 20 placebo patients had healed their duodenal ulcer compared with 16 of 20 ranitidine patients (p=0001). Lifestyle parameters of both groups improved during the study period but no directly related benefit in duodenal ulcer healing could be shown. We conclude that effective anti-ulcer therapy, such as ranitidine, is required to heal a duodenal ulcer which presents with haemorrhage.