Wiley

Data from a 1983 Auckland coronary heart disease register applying current World Health Organization criteria have been used to validate routine hospital discharge data. The register contained 905 patients under 65 years admitted to hospital and 858 of these patients were matched with hospital discharge records. Of the registered definite myocardial infarction cases 86% received the International Classification of Diseases code 410 (acute myocardial infarction); 9% of these cases received a code 411‐414 (other forms of coronary heart disease or angina) and 5% received other codes. Only 405 of the 604 cases (67%) coded 410 in the hospital discharge data were true definite myocardial infarctions according to the World Health Organization criteria. The routine hospital International Classification of Diseases data do not provide diagnostic groups sufficiently close to World Health Organization categories for them to be used alone to monitor trends in coronary heart disease morbidity rates.

Energy exchange based on Newtonian principles is the‐most appropriate way to express the function of any pump ‐ including the heart. Using information obtained at cardiac catheterisation, we have measured the total work energy (E_T) of the left ventricle (LV) (mean 1.63 J) in patients with severe mitral regurgitation (mean regurgitant fraction 0.66). E_T was approximately‐84% above normal. Of the regurgitant energy (RE)(mean 0.95 J), on average, ¾ (73.6%)was‐kinetic (KE) and ¼ (23‐4%) potential (PE). Both components represent wasted LV energy, the Kinetic energy associated with the lost as heat, the potential energy responsible for a fix in Left Atrial (LA) pressure. The‐amount of PE as a percentage of total regurgitant Energy (RE) varied considerably from, one patient to another (10.5% to 54.4%) Hence, colour flow mapping which detects‐only KE of turbulent jet flow must underestimate LV energy loss and, because of patient to patient variation, cannot consistently reflect severity of regurgitation. Measurements of PE correlate well with wedge P‐wave height. Corresponding non‐invasive estimates were made using sphygmodynamometer‐calibrated indirect carotid pulse tracings and echocardiographic measurements. These were not significantly different from the invasive measurements. Unfortunately, the calculation of PE is indirect and invlves subtraction, so that measurements for individual patients were not accurate enough, for clinical use. Paxt of the non‐invasive calculation involved an estimate of left atrial pressure based on the blood pressure measurement and Doppler velocity of regurgitation; this should be a useful measurement in itself. Measurement of E_T, an index of both volume and pressure overload (reflecting peripheral resistance changes), should be tested in serial studies as a predictor of left ventricular‐failure in severe mitral regurgitation. Non‐invasive measurements would be useful to follow patients with acute severe mural regurgitation: Non‐invasive PE measurements are currently not reliable enough but an indirect measurement of left atrial pressure would be very useful.

Background: Sub‐optimal use of prescribed medication is often associated with unplanned hospitalisation among the chronically ill.

Aims: To examine the extent of sub‐optimal use of prescribed medication in a ‘high risk’ patient cohort recently discharged from acute hospital care.

Methods: Chronically ill patients discharged from acute hospital care (n=342) were studied. At one week post discharge a home visit was performed by a nurse and a pharmacist during which medication management (including compliance and medication—related knowledge) was assessed.

Results: During the majority of home visits at least one medication‐related problem was detected: approximately half of the cohort subject to a ‘reliable’ pill‐count were found to be mal‐compliant and almost all demonstrated inadequate medication‐related knowledge. Mal‐compliance was correlated with ≥ five prescribed medications (Odds ratio [OR] 2.6: p <0.002). Comparatively, lower medication‐related knowledge was correlated with age >75 years (OR 2.2: p <0.001), exacerbation of a pre‐existing chronic illness (OR 2.7: p=0.044) and six years formal education (OR 1.9: p≥0.004). Neither were modulated by extent of in‐hospital counselling. Other previously unknown problems detected during the home visit included hoarding of previously prescribed medication (35%) and reducing medication intake to minimise costs (21%).

Conclusions: Management of prescribed medications among chronically ill patients recently discharged from acute hospital care is often sub‐optimal. Assessment of medication management in the home provides an invaluable opportunity to detect and address problems likely to result in poorer health outcomes.

Cryptococcosis is a known opportunistic infection in immunosuppressed hosts. We report our experience of all cases presenting to our Department between December 1975 and September 1988. Eight post‐renal transplant patients and three systemic lupus erythematosus (SLE) patients were affected. All were receiving treatment with steroids, in association with either azathioprine or cyclosporin. The diagnosis of cryptococcal meningitis was initially based on a positive cerebrospinal fluid (CSF) cryptococcal antigen, by latex agglutination test, and subsequently confirmed by cultures. Common clinical presentations, in descending order of frequency, included headaches, fever, mental confusion, epilepsy and papilloedema. Meningism was not a prominent feature. CT brain scans were obtained in eight patients and one showed a focal lesion and one showed cerebral atrophy. Four patients also had an abnormal chest X‐ray (CXR) and one had disseminated cryptococcosis. Amphotericin and 5‐fluorocytosine were the mainstay of therapy, although ketoconazole alone was subsequently used in three selected patients with cure. Four early deaths occurred in patients with delayed diagnosis and treatment, usually in association with other severe concurrent infections. We conclude that awareness of cryptococcosis is essential in immunocompromised hosts presenting with headaches with, or without, mental confusion or fever.

Pneumatocoele and pneumothorax are uncommon complications of Pneumocystis carinii pneumonia. We report a patient with the Acquired Immune Deficiency Syndrome who developed multiple bilateral pneumatocoeles which we demonstrate to have ruptured leading to the subsequent bilateral tension pneumothoraces and to death. The computerised tomographic appearances, and histopathology of these unusual complications are presented. The literature on these manifestations is reviewed and management discussed.

Background: Conventional methods of quantifying heart rate variability using summary statistics have shown that decreased variability is associated with increased mortality in heart failure. However, many patients with heart failure have arrhythmias which make the ‘raw’ heart rate variability data less suitable for the use of summary statistical measures.

Aims: To examine the clinical potential of a new measure of heart rate variability data, presented by the Poincare plot pattern, as an adjunct to the summary statistical measures of R‐R interval

Methods: We used the Poincaré plot pattern to display beat‐to‐beat heart rate variability data from a group of 23 patients with heart failure and compared them with data collected from 20 healthy age‐matched control subjects. The data, which consisted of 2000 consecutive R‐R intervals, were gathered over 20–40 minutes while the subjects rested supine in a quiet darkened room.

Results: The morphological classification scheme proposed reflected the functional status of patients in heart failure. There was a significant difference (chi‐square = 27.5, df = 6, ρ < 0.0001) in the different pattern types between patients with NYHA Class I and II compared to patients with NYHA Class III and IV. All healthy subjects displayed a ‘cluster’ type of pattern characterised by normally distributed data. Sixteen of the 23 patients in heart failure also produced data which were normally distributed but the remaining seven produced data which required careful filtering to make them suitable for analysis using summary statistics, but which could be analysed by the Poincare plot.

Conclusions: The Poincaréot pattern is a semi‐quantitative tool which can be applied to the analysis of R‐R interval data. It has potential advantages in that it allows assessment of data which are grossly non‐Gaussian in distribution, and is a simple and easily implemented method which can be used in a clinical setting to augment the standard electrocardiogram to provide ‘real time’ visualisation of data.

We studied 925 consecutive patients hospitalised with acute stroke to determine how stroke type, age, gender and risk factors influence acute, in‐hospital outcome. Stroke types included carotid territory cortical or large subcortical infarction (52%), vertebrobasilar infarction (12%), lacunar infarction (11%), intracerebral haemorrhage (16%), and subarachnoid haemorrhage (9%). Mean age (mean ± 1 SD) was 66 ± 15 years, but patients with cerebral infarction were older than those with cerebral haemorrhage. The prevalence of hypertension, diabetes mellitus and cardiac disease increased with age across all stroke types, while the prevalence of smoking decreased with age. Mortality was 19% overall, but varied significantly between stroke types, highest in intracerebral haemorrhage (34%), and lowest in lacunar infarction (1%). Age had a marked adverse effect on mortality, independent of stroke type, the probability of death increasing by 3 ± 0.5% per year from 20–92 years, whereas gender had no effect. Cardiac disease and diabetes were independent adverse prognostic factors (Odds Ratios 1.6 and 1.5 respectively). Cerebral haemorrhage, age, cardiac disease and diabetes all independently worsen acute stroke outcome. (Aust NZ J Med 1992; 22: 30–35.)

Abstract: The influence of the xanthine derivative pentoxifylline (‘Trental’ or BL191; Hoechst–Roussel) on exercise tolerance was measured in 38 subjects with stable, severe to moderately severe, intermittent claudication who completed a randomised, double–blind, placebo controlled, cross–over clinical trial. Patients received placebo tablets or 400 mg slow–release pentoxifylline tablets (‘Trental 400’) twice a day for one week, followed by three times daily for seven weeks, and then crossed over to receive the alternate preparation for another eight weeks.

Claudication distance and walking distance were measured on a treadmill before starting treatment and again at four–week intervals during the trial. At the same times, red blood cell filterability, plasma fibrinogen concentration and blood viscosity, resting and post–ischemic calf muscle blood flow, and the resting and post–exercise ankle/brachial systolic pressure ratio were also measured.

In this study, the observed effects of pentoxifylline treatment were no greater than those of placebo, even though serum levels of pentoxifylline and its hydroxy–metabolite were within the anticipated range. This was shown by a ‘therapeutic effect ratio’ of 0.98 for treadmill claudication distance and 0.96 for treadmill walking distance after within–patient analysis at the end of the cross–over (where a ratio of 1.0 means the test drug and placebo effects are identical). These ratios have 95% confidence limits of 0.72–1.34 and 0.74–1.25, respectively.

The Sydney AIDS Project is a prospective immunoepidemiological study of 996 homosexual/bisexual men enrolled between February 1984 and January 1985. By January 1987, 32 of 386 homosexual men who were seropositive at enrolment in the study had developed AIDS, yielding a crude progression rate of between 2.8% and 4.2% per annum. Of these subjects, 23 (72%) developed AIDS within 12 months of enrolment.

In univariate analysis, the only lifestyle differences between seropositive subjects who progressed to AIDS and those that did not progress were less frequent oral sex activity and more use of marijuana in the three months prior to enrolment. In multivariate analysis, seropositive subjects who progressed to AIDS were more likely to have a lower percentage of CD4+ cells, a higher percentage of CD8+ cells and to have used marijuana in the three months prior to enrolment than the seropositive subjects who did not progress. No HIV seropositive subject who was asymptomatic and had normal T‐cell subsets at enrolment had developed AIDS by January 1987. Persistent generalised lymphadenopathy was not associated with progression to AIDS.

Although there are a number of lifestyle factors that may be associated with HIV infection, this study did not implicate most of these in the progression of HIV seropositive subjects to end‐stage AIDS. We conclude that antecedent changes in T‐cell subsets are associated with progression to AIDS and we emphasise the prognostic value of enumeration of T‐cell subsets in HIV seropositive persons. (Aust NZ J Med 1988; 18: 8–15).