Abdominal distension after colonic lactulose fermentation recorded by a new extensometer

Colonic lactulose fermentation induces bloating, but whether it also causes abdominal distension is not known. The aim of this study was to assess the effect of colonic lactulose fermentation on abdominal girth using a new extensometer. We recorded abdominal girth in 24 healthy subjects by means of an extensometer that measures the phase shift of an ultrasound wave propagating in a tube encircling the abdomen. The recordings were continuously made for 3 h after the ingestion of 100 mL of tap water with (16 subjects) or without (eight subjects) 10 g of lactulose. Every 10 min, H2 in the breath was analysed and the intensity of bloating was recorded. Bloating was never reported after water ingestion, whereas it was reported by 10 subjects after lactulose ingestion (P = 0.002). The mean +/- SD changes in abdominal girth in comparison with resting conditions were statistically significant after lactulose ingestion (3 +/- 2.9 mm; P = 0.002) but not after water ingestion (-0.2 +/- 2.7 mm; P = 0.82). The area under the curve of the changes in abdominal girth after lactulose were significantly greater than after water ingestion (P = 0.03). In conclusion, colonic lactulose fermentation induces bloating and abdominal distension. The new extensometer is useful for continuously recording changes in abdominal girth.     

Primary endobronchial actinomycosis

A male farmer referred for fever, cough and haemoptysis, presented, at bronchoscopic examination, a large mass occluding the middle lobe bronchus. No lung involvement was visible on chest X-ray. Histological examination showed an actinomycotic granule in the bronchial submucosa. The histological findings indicate that aspiration of contaminated material from the upper alimentary tract may have caused the disease.     

Surgical bypass of the systemic atrioventricular valve in children by means of a valved conduit

The surgical approach to relief of mitral stenosis in children is still a controversial problem. We describe our experience with four severely symptomatic children in whom a valved conduit from the left atrium to the left ventricle was successfully used to bypass a hypoplastic systemic atrioventricular valve. A left atrial-left ventricular extracardiac conduit was implanted in these patients with a hypoplastic mitral anulus and an adequate left ventricular chamber. There were no early or late deaths. Postoperative cardiac catheterization performed in all patients 1 month after the operation showed reduced size of the left atrium, a reduction of the left atrial-left ventricular gradient from a mean of 14 mm Hg to a mean of 5 mm Hg, and an increase of the left atrial outlet from a mean diameter of 10.7 mm to 28.7 mm (including the diameter of the native mitral valve plus the internal diameter of the valved conduit). The application of this unconventional operation in children with congenital or acquired stenosis of the systemic atrioventricular valve should be considered when the mitral valve obstruction cannot be relieved by conventional valve repair or replacement. Furthermore, the left atrial-left ventricular conduit does not preclude future alternative surgical options.     

Metabolic consequences of physical inactivity.

Physical inactivity is associated with alteration of normal physiologic processes leading to muscle atrophy, reduced exercise capacity, insulin resistance, and altered energy balance. Bed rest studies in human beings using stable isotopes of amino acids indicate that muscle unloading decreases the turnover rates of muscle and whole-body proteins, with a prevailing inhibition of protein synthesis. In the fasting state, muscle and whole-body nitrogen loss was not accelerated during bed rest. In experimental postprandial states, the amino acid-mediated stimulation of protein synthesis was impaired, whereas the ability of combined insulin and glucose infusion to decrease whole-body proteolysis was not affected by muscle inactivity. Thus, an impaired ability of protein/amino acid feeding to stimulate body protein synthesis is the major catabolic mechanism for the effect of bed rest on protein metabolism. This suggests that a protein intake level greater than normal could be required to achieve the same postprandial anabolic effect during muscle inactivity. Metabolic adaptation to muscle inactivity also involves development of resistance to the glucoregulatory action of insulin, decreased energy requirements, and increased insulin and leptin secretion. These alterations may lead to the development of the metabolic syndrome that is defined as the association of hyperinsulinemia, dyslipidemia, hypertension, hyperglycemia, and abdominal obesity. This cluster of metabolic abnormalities is a risk factor for coronary artery disease and stroke. Evidence indicates that exercise training programs may counteract all of these abnormalities both in healthy sedentary subjects and in patients affected by a variety of chronic disease states.     

Bidirectional cavopulmonary shunts: clinical applications as staged or definitive palliation

A standard Glenn anastomosis between the superior vena cava and the right pulmonary artery has been the accepted mode of treatment for patients with complex cyanotic congenital heart disease. We report our experience in 18 patients with such disease who underwent a bidirectional cavopulmonary shunt because of increasing cyanosis and growth cessation. All patients were considered less than "ideal" candidates for a Fontan procedure. We divided the patients into two groups: group 1 had azygos continuation and group 2 did not. Fourteen patients required hypothermic cardiopulmonary bypass. Bidirectional pulmonary blood flow was achieved in all patients. Only 1 death occurred (group 2). The improvement in oxygen saturation and overall clinical condition of these patients, together with the low mortality and morbidity, is encouraging. However, long-term follow-up is mandatory for a comprehensive evaluation of this surgical approach as definitive palliation or as a first stage for a Fontan operation.     

Thrombus of the ascending aorta: a rare cause of myocardial infarction.

We present two cases of a thrombus in the ascending aorta causing an acute myocardial infarction (AMI) and review the 10 other cases previously reported in the literature. This life-threatening condition appears to be more common in female smokers in their fifth decade. Suspicion should be raised in individuals at low risk for atherosclerotic disease with coronary angiographic findings not in keeping with the clinical presentation. The diagnosis may be obtained by transesophageal echocardiography, and we generally recommend surgical thrombectomy.