Right-to-left shunting through a patent foramen ovale caused by pulmonary hypertension associated with rheumatoid arthritis and Sj?gren's syndrome: a case report

This case report presents a fifty-four-year-old woman with right-to-left shunt in the atrium. It seemed clinically at first that the shunt was due to atrial septal defect. However, she also had pulmonary disease associated with rheumatoid arthritis and Sj?gren's syndrome. At autopsy atrial septal defect was not evident, but a patent foramen ovale and pulmonary artery disease were observed. This case suggests that pulmonary hypertension secondary to rheumatoid arthritis and Sj?gren's syndrome could lead to right-to-left shunting through a patent foramen ovale.     

Nitroglycerin-induced transient coronary artery occlusion

Nitroglycerin induced a paradoxical disappearance of a stenosed coronary artery in a 57-year-old man with non-Q wave myocardial infarction. On the coronary angiogram, the left anterior descending coronary artery (with a 95% stenosis) became completely invisible 2 min after 0.3 mg sublingual nitroglycerin. Three minutes later, the artery was opacified again. This transient occlusion may have resulted from a passive collapse of the distal portion of the artery, due to insufficient access of nitroglycerin across the stenotic region.     

Direct discrimination and full-day disclosure of ventricular parasystole on new heart rate tachograms

INTRODUCTION: To discriminate ventricular parasystole from fixed coupling interval ventricular premature complexes (VPCs), we developed a new diagnostic method using a dot distribution pattern corresponding to VPCs recorded on a heart rate tachogram using ambulatory ECG monitoring data. We tested our hypothesis that widely scattered VPC dots on instantaneous heart rate tachograms indicate a constant VPC-VPC interval compatible with parasystole. METHODS AND RESULTS: Patients with frequent VPCs > 5,000/day) were divided into two groups depending on the tachogram dot distribution patterns: group S (n = 10, aged 61 +/- 16 years) showed widely scattered VPC dot distribution, whereas group F (n = 10, 60 +/- 17 years) showed fixed VPC dot distribution limited to a narrow zone. Using digitized R-R interval data, full-day heart rate tachograms and VPC-VPC intervals were depicted simultaneously. Group S demonstrated constant basic VPC-VPC intervals (1,285 to 2,052 msec, mean 1,738 +/- 219), with a coefficient of variation (CV) of 0.061 +/- 0.018. Their VPC coupling intervals were markedly variable (651 +/- 113 msec; CV = 0.193 +/- 0.034). Each patient's basic VPC-VPC intervals showed small diurnal alterations (minimum -13% +/- 3% to maximum +15% +/- 6%). VPC-VPC intervals in group F were not constant and showed marked variation. Group F VPC coupling intervals were shorter and constant (480 +/- 30 msec, P = 0.0002; with CV = 0.076 +/- 0.013, P < 0.0001). CONCLUSION: Ventricular parasystole with constant VPC-VPC intervals consistently became evident based on VPC dot patterns recorded on heart rate tachograms.     

Effects of PHEX antisense in human osteoblast cells.

X-linked hypophosphatemia (XLH) is an X-linked dominant disorder that is characterized by rachitic bone disease and hypophosphatemia due to renal phosphate transport defect. The candidate gene for XLH, PHEX, has recently been identified and found to share high homology with endopeptidases. PHEX is expressed in various tissues, including bones, and the available evidence today indicates that bones can release abnormal humoral factors that affect bone mineralization and proximal tubule phosphate transport in XLH. It was, therefore, hypothesized that the inactivating mutations of PHEX in bone may lead to the release of humoral factors and contribute to the phenotypic expression of the disease. To test this possibility, clones of MG-63 cells, a human osteoblast cell line, were produced and stably transfected with PHEX-antisense vectors, resulting in a decrease in PHEX expression at mRNA and protein levels. It was found that these antisense-transfected cells had impaired mineralization, with a decrease in 45Ca incorporation and calcification nodule formation. It was also found that the conditioned culture media collected from these antisense-transfected cells exhibited inhibitory activities on 45Ca incorporation by the nontransfected MG-63 cells and 32P uptake by the opossum kidney proximal tubular cells. The results of the study, therefore, provide strong evidence that supports the link between PHEX mutations and the pathogenesis of XLH.     

Effects of the Na ionophore monensin on the contractile response and the movements of monovalent cations in the vascular smooth muscle of rabbit aorta

Summary The effects of monensin, a Na ionophore, on the muscle contraction and the movements of monovalent cations were investigated in rabbit aorta. Experiments were conducted in the presence of phentolamine (10^–6 M) to avoid the vasoactive effect of monensin due to the release of endogenous catecholamine. Both monensin (2×10^–5 M) and ouabain (2×10^–5 M), added separately, produced a small and slowly developing contraction, whereas simultaneous application of these agents produced more rapid and greater contraction. Verapamil (10^–6 M) decreased the contraction by 75%. Ouabain gradually increased cellular Na content. Monensin augmented the ouabain-induced Na increase. Further, the loss of cellular Na into Na deficient solution was enhanced by monensin. Low temperature (0.5°C) inhibited the monensin-induced increase in Na permeability. The relaxation of noradrenaline-contraction induced by a K-readmission was inhibited by ouabain but not by monensin. These results suggest that monensin increases Na movement down its electrochemical gradient, augments cellular Na accumulation when the Na pump is inhibited by ouabain, and induces muscle contraction, and that the contraction induced by monensin and ouabain is mainly due to an increased Ca influx through voltage sensitive Ca channels.     

A patient with alternating hemiplegia in childhood

Alternating hemiplegia in childhood (Verret, 1971) is a disorder presenting with frequent episodes of alternating hemiplegia from early infancy. We report a patient with this disorder, along with a pathophysiological study and a discussion about the available therapies for this disorder. The patient, an 11-year-old boy, visited our hospital with episodes of alternating hemiplegia from early infancy. His family history showed that many members suffered from migraine. He was born with asphyxia. Mental and motor developmental delays were seen from early infancy. The hemiplegic episodes with ipsilateral facial palsy had occurred frequently from early infancy. The episodes were frequently induced by emotional stress. The duration of hemiplegia varied from 10 minutes to 3 days. From the age of 11 years, he had begun to have migrainous attacks with or without hemiplegic episodes. Neurological examination revealed slight muscle hypotonia, choreoathetosis and dystonic movements induced by locomotion, positive Myerson sign, increased deep tendon reflexes and Babinski reflex. CAG, VAG and CAT revealed normal findings. EEG revealed diffuse generalized slowing during hemiplegic episodes. Measurement of regional cerebral blood flow (CBF) by 133Xe inhalation method revealed a slight decrease of bilateral CBF during a quadriplegic episode. Positron emission tomography using C15O2 revealed a slight decrease of CBF at the insula, putamen and claustrum of the left side during a right sided episode. Increased excretion of urinary 5-HIAA was seen during one episode. From our clinical and laboratory findings, we think this disorder may be a special type of migraine. Therapeutic trials of diazepam and flunarizine were both effective, but the initial effectiveness was decreased after 5 months.     

Aneurysm of peripheral cerebral arteries with developmental anomaly of the anterior cerebral artery

We report a 71-year-old woman who was initially admitted because of a ruptured internal carotid aneurysm, and found to have an aneurysm of the terminal portion (A5 portion) of pericallosal artery. Both of the aneurysms were surgically treated at one stage operation. A saccular aneurysm of the pericallosal artery was verified at operation. Right internal carotid angiography disclosed that medial part of the right anterior cerebral hemisphere was supplied by the right callosomarginal artery, and that unpaired pericallosal artery made a trifurcation at A5 portion, where the saccular aneurysm arose. According to Baptista's classification, anomaly of the anterior cerebral artery (ACA) in this patient was bihemispheric ACA type. Distal ACA aneurysms almost always locate at or near the genu of corpus callosum, either in pericallosal-callosomarginal or in pericallosal-frontopolar junction. In reviewing the literature, we were able to find 14 cases, including ours, of aneurysms located beyond either pericallosal-callosomarginal junction or the genu of corpus callosum. Also the possible role of hemodynamic stress caused by vascular anomaly for aneurysm formation are discussed.