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A total of 206 patients with Marfan syndrome were ascertained throughout genetic clinics in Wales and Scotland during the period 1970-1990. There were 45 deaths representing 22% of the cohort. Mean age at death was 45.3+/-16.5 years. 50% median cumulative survival in the total cohort (n=206) was 53 years for males and 72 years for females. Multivariate analysis confirmed severity as the best independent indicator of survival. These findings and survival curves will assist in the counselling of British families and individuals with Marfan syndrome.

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Concomitant coronary artery disease often occurs in patients with peripheral vascular disease, but it may be asymptomatic. Despite being asymptomatic, cardiovascular events are the main source of morbidity and mortality in this group of patients. Dipyridamole thallium scintigraphy has been shown to be of prognostic value in patients with peripheral vascular disease and symptomatic coronary artery disease, but its effect on the long-term outcome in the asymptomatic group of patients is less defined. Eighty-four consecutive patients with peripheral vascular disease and no symptoms of coronary artery disease were therefore evaluated by clinical assessment, dipyridamole thallium imaging, radionuclide ventriculography, and cardiac catheterization and followed for a mean of 66 months. Abnormal perfusion patterns were found on thallium scintigraphy in 48 patients (57%); fixed, mixed, and reversible defects were present in 14 (17%), 11 (13%), and 23 (27%) patients, respectively. Significant coronary artery disease was present in 52 patients (69%) and mean left ventricular ejection fraction was 44%. During the follow-up period, 23 patients had a cardiac event (nonfatal myocardial infarction or cardiac death). Univariate analysis of 15 clinical, scintigraphic, radionuclide, and angiographic variables revealed that age, angiographic extent of coronary artery disease, and an abnormal thallium scan were significant predictors of subsequent cardiac events. Multivariate stepwise logistic regression analyses selected fixed and mixed thallium defects and diffuse coronary artery disease as the only significant independent predictors of outcome. Thus, the present study shows the value of dipyridamole thallium scintigraphy as a valuable prognostic indicator for long-term event-free survival in a cohort of patients with peripheral vascular disease and no history or symptoms of coronary artery disease.

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Angiotensin-converting enzyme (ACE) inhibitors have been shown to reduce the incidence of future coronary artery thromboses in postmyocardial infarction patients. A possible prothrombotic role for the angiotensin system has been postulated, and support for this has been provided by a recent study that demonstrated that an infusion of angiotensin increases levels of the prothrombotic plasminogen activator inhibitor (PAI). In the current study the authors have investigated the effect of two ACE inhibitors, captopril and enalapril, on tissue plasminogen activator (tPA) and PAI in 33 congestive heart failure (CHF) patients. Blood samples were obtained pretreatment and then at weeks 1, 12, and 24 after initiation of ACE inhibitor therapy for measurement of tPA antigen and PAI activity levels. The results of the study indicated that the initiation of ACE inhibitors had no significant effects on tPA antigen or PAI activity levels at the time points studied, and no significant differences were demonstrated between captopril and enalapril. The results suggest, therefore, that ACE inhibitors do not affect tPA antigen or PAI activity in CHF patients, and thus another mechanism is probably responsible for the observed decrease in coronary artery thromboses in post-MI patients treated with ACE inhibitors.

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Free radicals (FR) are a highly reactive chemical species which have been implicated in the pathogenesis of reperfusion injury. Experimental models of reperfusion injury have demonstrated that FR scavengers improve myocardial salvage and thus it has been postulated that they may be of benefit in acute myocardial infarct (MI) patients treated with thrombolysis. Previous studies of FR activity post MI have focused on the immediate post reperfusion period; the present study investigates FR activity in post MI patients over a longer time span. Free radicals have a very short half-life and in clinical studies their activity is usually assessed indirectly by measuring either the level of FR reaction products such as malondialdehyde (MDA) or FR scavengers such as plasma thiols (PSH). In the presence of increased FR activity MDA levels increase and PSH levels decrease. Twenty-two acute MI patients had blood samples taken on admission, day 7 and day 21 post MI for measurement of MDA and PSH levels. On day 7 post MI a significant increase in MDA was detected P = 0.0001 (Sign test) (median change +2.1 mumol.l) and a significant decrease was detected in PSH P = 0.04 (Sign test) (median change, -38 mumol.l-1). No significant differences were detected between admission and day 21 levels of MDA and PSH. This study demonstrates the presence of enhanced FR activity at a later time point than has previously been recognised. White blood cells utilise FRs during phagocytosis and the late rise in FR activity detected in this study may reflect white blood cell removal of necrotic myocardium.

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Cor triatriatum is a rare congenital cardiac malformation, and in its most common form is characterised by a membrane that separates the left atrium into a proximal and distal chamber. First manifestation in adulthood has been reported previously, but at 67 years of age this patient is one of the oldest to present for the first time. It was diagnosed after a probable TIA, episodic vertigo and central retinal artery occlusion. The value of echocardiography in patients with neurological disease of presumed embolic origin is demonstrated here.

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This study in north east Scotland has shown that Marfan syndrome has a minimal birth incidence of 1:9802 live births, a minimal prevalence of 1:14217, and that 8/30 (26.7%) of cases in our series are new mutations. The calculated mutation rate is 15 +/- 6.7 x 10(-6) and there is evidence of reduced reproductive fitness.

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This study examined the effects of conventional doses of oral captopril on the renal responses to oral furosemide in ambulant patients with stable chronic heart failure. Twenty-five men (mean age 63 years) were randomized to one of two groups. Group 1 received placebo on days 1 and 2 before furosemide. Group 2 received placebo on day 1 before furosemide and captopril thereafter (i.e., captopril before furosemide on day 2). Urine was collected after either placebo or captopril and after furosemide (taken after placebo or captopril pretreatment). Captopril by itself did not affect renal function. Captopril did, however, significantly affect the renal response to furosemide. The increase in urine flow rate after furosemide in group 2 was decreased from 225% with placebo to 128% with captopril (p < 0.02). The increase in sodium excretion after furosemide was decreased from 623% with placebo to 242% with captopril (p < 0.001). Pretreatment with captopril abolished the increase in creatine clearance after furosemide. The increase in urinary albumin excretion (used as a marker of glomerular function) after furosemide was also significantly blunted by captopril. Conventional doses of captopril acutely inhibit the natriuretic and diuretic responses to furosemide at the glomerular level in ambulant patients with stable chronic heart failure.

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The effect of the injection of additional thallium after a redistribution study and prior to a further resting study was evaluated in 21 patients with angiographically proven coronary artery disease. Using dipyridamole as the stress mechanism, the studies were carried out tomographically and the results analysed quantitatively with the Bull's-eye technique. Two patients had normal scans. Of the remaining 19, 11 patients had a perfusion defect which appeared irreversible on redistribution imaging. However, six of these patients demonstrated improved or normal uptake after the second injection of thallium. Of the eight patients with a reversible defect, two revealed considerably greater reversibility after reinjection. These results indicate that the reinjection of thallium prior to the resting study significantly (P < 0.02) improves the detection rate of ischaemia during dipyridamole thallium tomography.

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Fourteen patients with Marfan syndrome, defined according to present criteria, had bone mineral content of the distal forearm measured by single photon absorptiometry. Patients were matched for age and sex with a large local group of healthy volunteers. While further work is needed with other methods of densitometry with measurements at other sites, our results provide no evidence that there is an increased incidence of osteoporosis in Marfan syndrome. Previous reports of an association were probably due to incorrect clinical diagnosis or confusion with clinically similar syndromes known to cause osteoporosis.

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OBJECTIVES: To determine the effect of age, sex and smoking on free radical (FR) indices. There is currently considerable research interest into the role of FRs in the pathogenesis of many diseases and it is therefore important to identify factors in healthy subjects which influence the markers used to assess FR activity. METHODS: Blood samples were obtained from 123 healthy subjects whose age, sex and smoking habits were recorded. The following were measured on each sample: malondialdehyde (MDA) which is a product of FR mediated lipid peroxidation and the FR scavengers plasma thiols (PSH), red cell glutathione (GSH) and superoxide dismutase (SOD). RESULTS: Malondialdehyde levels were significantly increased in cigarette smokers (p < 0.02) but no significant age related increase in MDA was detected for the group as a whole. However, female smokers had the highest rate of MDA increase with age followed by male smokers and female non-smokers. MDA levels of male non-smokers were unaffected by age. A significant negative correlation was detected between PSH and age (p < 0.001). GSH was significantly higher in females (p < 0.05) and the red cell content of GSH and SOD were significantly inversely related (p < 0.01). CONCLUSION: This study of normal subjects describes an age related increase in malondialdehyde levels, the rate of which is influenced by sex and smoking status. In humans, plasma thiol levels decrease with increasing age, females have higher red cell glutathione and there is a significant inverse relationship between red blood cell superoxide dismutase and glutathione levels. Furthermore, cigarette smoking increases plasma malondialdehyde levels. With the considerable current interest in free radicals, it is important to identify factors which influence the indices used to assess free radical activity in disease states.

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We studied the effect of chronic cigarette smoking on white blood cell aggregation, increased aggregation predisposes to microvascular occlusion and damage. Current smokers had significantly increased white blood cell aggregation when compared with non smokers. The presence of chronically activated white blood cells in current smokers may be relevant in the pathogenesis of ischaemic vascular disease.

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OBJECTIVES: To determine whether plasma concentrations of tissue plasminogen activator antigen, von Willebrand factor antigen, and prostacyclin stimulating factor and plasminogen activator inhibitor activity show circadian variation in men with ischaemic heart disease. DESIGN: Blood samples were obtained every four hours for 24 hours from 10 men with ischaemic heart disease. The men were ambulant from 08:10 until 00:00 when they went to bed and they remained in bed until 08:00 the following morning. PATIENTS: Ten men with positive diagnostic exercise tolerance tests with no significant past history, who were not regularly taking any medical treatment except for glyceryl trinitrate. RESULTS: There was significant circadian variation in plasminogen activator inhibitor activity (p = 0.001) (peak value 04:00 and trough value 20:00), but not in plasma concentrations of tissue plasminogen activator antigen, von Willebrand factor, or prostacyclin stimulating factor. CONCLUSION: Men with ischaemic heart disease showed a significant circadian variation in fibrinolysis. The combination of peak values of plasminogen activator inhibitor activity and failure of plasma concentrations of tissue plasminogen activator antigen to increase in the early morning must predispose to thrombosis at this time. The circadian variation in fibrinolysis may contribute to the increased incidence of myocardial infarction in the morning.

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The cardiopulmonary skills of one intake of junior house officers (JHOs) were assessed and all then underwent a six hour training course. In the following six months we studied the outcomes of 83 cardiopulmonary resuscitation attempts and compared them with results obtained in our hospital two years earlier as part of a multicentre survey when no formal training was undertaken. The JHOs performed poorly in all assessments before training. The initial and long-term survival rates in the present study were no better than in the earlier. There were 12 long-term survivors, 11 required defibrillation. Decreasing the time taken to defibrillation and training other members of the arrest team in addition may lead to improved survival. The training of junior house officers alone is not an effective strategy for improving survival from cardiac arrest.

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Markers suggestive of enhanced free radical (FR) activity have been demonstrated in patients with chest pain and normal coronary angiograms. This may be of pathogenetic importance because FRs impair vascular relaxation and are generated following episodes of myocardial ischaemia/reperfusion. Fifteen patients with angina pectoris, normal coronary angiograms and either a positive exercise tolerance test and/or abnormal dipyridamole thallium tomogram were studied along with 15 age-, sex- and smoking-matched controls. A peripheral venous blood sample was obtained to measure the following FR markers: malondialdehyde, plasma thiols, red blood cell glutathione and superoxide dismutase. No significant differences were detected in the levels of any of the FR markers between either the group of 15 patients with chest pain and normal angiograms or the subgroup with positive exercise tolerance tests when compared to the controls. There is therefore no evidence of enhanced FR activity in patients with chest pain and normal coronary angiograms in peripheral venous blood samples.

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A 40 year old man suffered eight years of vague but disabling symptoms, initially thought to be related to post viral fatigue syndrome, but ameliorated by the removal of a large atrial myxoma. The diagnosis of atrial myxoma is notoriously difficult, but should be excluded by echocardiography if there are predominant symptoms of progressive exertional dyspnoea, even in the absence of cardiological signs.

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The fibrinolytic activity of blood has a circadian variation with increased thrombotic tendency in the morning. This may be a contributory factor to the circadian variation in the time of onset of thrombotic events. However, there has recently been increasing interest to the role of the white blood cells (WBC) and free radicals (FRs) in thrombosis. We have previously reported a circadian variation in WBC aggregation and FR status in normal volunteers. No one has yet studied possible circadian variations in these parameters in patients with stable ischaemic heart disease (IHD). Ten men with stable IHD had blood samples collected at four-hourly intervals from midday until midday the following day. The patients were ambulant until midnight at which time they went to bed and remained in bed until 0800 h. The following were measured on each sample: WBC aggregation, malondialdehyde (MDA) which is a product of lipid peroxidation by FRs; the FR scavengers, plasma thiol (PSH), red cell glutathione (GSH) and superoxide dismutase (SOD) which are all altered in the presence of increased FR activity. WBC aggregation and PSH had significant circadian variations, P < 0.015 and P < 0.001 respectively. The WBC aggregation peak was at 1200 h and trough at 1600 h, the PSH peak was at midnight and the trough at 0400 h. WBC behaviour and FR status influence the flow properties of blood. The largest rise in WBC aggregation occurred from 0800 h to 1200 h; such an increase in aggregation could predispose to microcirculatory occlusion.(ABSTRACT TRUNCATED AT 250 WORDS)

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