Hypoxia and abnormal pulmonary pressure response (AR) during exercise have been observed in healthy individuals. AR has been shown to correlate with susceptibility to high altitude pulmonary edema. It is not known whether moderate altitude can cause or augment these abnormal reactions in numerous patients with minor or surgically closed ventricular septal defect (VSD) or atrial septal defect (ASD) with increased pulmonary vascular reactivity early in life. PURPOSE: To show if moderate altidue conditions with and without exercise simulating the atmospheric condition in mountainous areas or in pressurised commercial airplanes can provoke or augment abnormal pulmonary arterial pressure response in VSD/ASD-patients. METHODS: 11 patients with ASD or VSD (10/11 surgically closed, age 14 to 25 yrs) were examined by echocardiography at rest and during supine cycling at sea level. The patients then rested in a low-pressure chamber for 2 hours at 2500 meters / 8200 feet altitude. Oxygen saturation (SpO2), right ventricular performance and pulmonary arterial peak systolic pressure (PAP) were monitored. Exercise echocardiography was repeated before descent. RESULTS: During exercise at sea level 3 patients showed abnormal PAP response > 40 mmHg (44 to 56), none had hypoxia (mean 98.6%). After 120 minutes resting at moderate altitude mean PAP increased from 24 mmHg at sea level to 32 mmHg, 3 patients showed PAP increase above 40 mmHg (43 to 45), mean SpO had fallen to 94% (88 to 98). During altitude exercise mean PAP raised to 49 mmHg, 9 patients showed PAP > 40 mmHg (41 to 63), mean oxygen saturation dropped to 81%, in 3 patients SpO decreased below 80% (68 to 79). 2 of these patients had simultaneously hypoxia and pressure increase above 50 mmHg. No patient had symptoms beyond dizziness at rest or fatigue during altitude exercise. CONCLUSIONS: Like many other people patients with closed VSD or ASD may be exposed to these conditions for hours (airplane), days or months or even permanently (mountains) with or without physical strain. There might be a significant risk of hypoxia and pulmonary hypertensive reaction in patients with minor or surgically closed ASD or VSD when exposed to moderate altitude. Exercise in altitude seems regularly to provoke or augment abnormal pulmonary vascular resistance despite surgical repair early in life.
Cerebrocortical necrosis (CCN) was experimentally induced in three calves with the thiamine antagonist Amprolium. The calves were followed clinically. At the time of development of typical clinical signs of CCN the calves were killed and necropsied and a complete histopathologic examination was performed. The light microscopic lesions of the cerebral cortex were those of middle laminar necrosis and deep laminar edema. The necrotic zone consisted of fine vesicles and differed only slightly from the edema zone. In the former some neurons were morphologically normal, others showed signs of injury, while in the latter all neurons were injured. The lesions are consistent with those found in natural cases of CCN. Biopsies from the cerebral cortex were taken at the time of early clinical signs. Ultrastructural studies of these biopsies showed no clear difference between the zones of necrosis and edema observed light microscopically. The ultrastructural changes were characterized by dilatations in the neuropil. The cytoplasm and foot plates of the astrocytes had a "watery" appearance and contained dilated mitochondria and large vesicles. The vesicles were continuous with the granular endoplasmic reticulum. It was concluded that the initial morphologic changes in CCN in calves were indicative of a cytotoxic edema of the astrocytes. This may be due to a cytotoxic edema with subsequent loss of cell volume control. The primary astrocytic changes could then lead to neuronal injury.
Marine n-3 polyunsaturated fatty acids may protect against ischaemic heart disease.1 In the diet and reinfarction trial patients with an acute myocardial infarction advised to eat fish rich in n-3 polyunsaturated fatty acids had a 29% reduction in two year all cause mortality compared with controls.2 The authors hypothesised that dietary n-3 polyunsaturated fatty acids might reduce malignant ventricular arrhythmias and sudden cardiac death, as reported in animals.3 We investigated a possible antiarrhythmic effect of dietary n-3 polyunsaturated fatty acids in survivors of myocardial infarction.
Patients were eligible for study if they had been discharged from the department of cardiology at Aalborg Hospital between November 1991 and August 1993 after a myocardial infarction and had a ventricular ejection fraction below 0.40. We excluded patients aged over 75, patients with pacemakers or permanent tachyarrhythmias, and those with serious non-cardiac disease. Eighty one patients fulfilled the inclusion criteria and 55 gave informed consent to a double blind placebo controlled trial.
Patients were randomly …
Abstract Neuropsychiatric disease in systemic lupus erythematosus (NPSLE) is a poorly understood, but potentially fatal, disease manifestation. A pathogenetic role for autoantibodies is suspected, but the mechanism is unclear. Since immune complexes in SLE can stimulate IFN-α and there is strong evidence in humans and in mice that IFN-α can cause neuropsychiatric manifestations, we asked whether NPSLE patient serum and/or cerebrospinal fluid (CSF) contain abnormally high IFN-α-inducing activity. In a bioassay containing plasmacytoid dendritic cells and a source of Ag, NPSLE CSF induced significantly higher IFN-α compared with CSF from patients with multiple sclerosis or other autoimmune disease controls. When normalized for IgG concentration, NPSLE CSF was 800-fold more potent at inducing IFN-α compared with paired serum due to inhibitors present in serum. Analysis of Ig-deficient patient serum, depletion of IgG from normal serum, as well as addition of purified IgG to NPSLE CSF and serum in the bioassays revealed that one inhibitor was contained within the IgG fraction itself. In addition to IFN-α, immune complexes formed by CSF autoantibodies produced significantly increased levels of IFN-γ-inducible protein 10 (IP-10/CXCL), IL-8, and MCP-1, all of which have been reported to be elevated in CSF from NPSLE patients. Taken together, these findings are consistent with a two-step model of NPSLE whereby CSF autoantibodies bind to Ags released by neurocytotoxic Abs or other brain cell injury, and the resulting immune complexes stimulate IFN-α and proinflammatory cytokines and chemokines.
A report is given of eight cases of congenital, multiple peripheral stenoses of the pulmonary artery, diagnosed by means of cardiac catheterization and selective angiocardiography. These cases are divided into two types on the basis of the anatomic features, i.e., type I—simple membranous stenosis distal to the pulmonary valve, and type II–multiple, short or long bilateral constrictions extending from the main trunk to relatively fine branches.
Abstract BackgroundThe role of dysfunction of the single ventricle in Fontan failure is incompletely understood.ObjectivesWe aimed to evaluate haemodynamic responses to preload increase in Fontan circulation, to determine whether circulatory limitations in different locations identified by experimental preload increase are associated with cardiorespiratory fitness (CRF), and to assess the impact of left versus right ventricular morphology.MethodsIn 38 consecutive patients (median age=16.6 years, 16 females), heart catheterisation was supplemented with a rapid 5-mL/kg body weight volume expansion. Central venous pressure (CVP), ventricular end-diastolic pressure (VEDP), and peak systolic pressure were averaged for 15‒30 s, 45‒120 s, and 4‒6 min (steady state), respectively. CRF was assessed by peak oxygen consumption (VO 2peak ) and ventilatory threshold (VT).ResultsMedian CVP increased from 13 mmHg at baseline to 14.5 mmHg (p<0.001) at steady state. CVP increased by more than 20% in eight patients. Median VEDP increased from 10 mmHg at baseline to 11.5 mmHg (p<0.001). Ten patients had elevated VEDP at steady state, and in 21, VEDP increased more than 20%. The transpulmonary pressure difference (CVP‒VEDP) and CVP were consistently higher in patients with right ventricular morphology across repeated measurements. CVP at any stage was associated with VO 2peak and VT. VEDP after volume expansion was associated with VT.ConclusionsPreload challenge demonstrates the limitations beyond baseline measurements. Elevation of both CVP and VEDP are associated with impaired CRF. Transpulmonary flow limitation was more pronounced in right ventricular morphology. Ventricular dysfunction may contribute to functional impairment after Fontan operation in young adulthood.ClinicalTrials.govidentifier: NCT02378857
