[Pulmonary hypertension associated with disorders of the respiratory system]. / Hypertension pulmonaire des affections respiratoires chroniques.

Pulmonary hypertension associated with disorders of the respiratory system is defined by a pulmonary artery mean pressure above 20 mmHg at rest in stable disease. The most frequent form of precapillary pulmonary hypertension is associated with chronic obstructive pulmonary disease, because of its high prevalence. Pulmonary vascular remodeling occurs in the small pulmonary arteries and is due mainly to chronic alveolar hypoxia. Pulmonary hypertension associated with disorders of the respiratory system is usually mild to moderate, with resting pulmonary artery mean pressure ranging between 20 and 35 mm Hg. It may increase markedly during sleep, exercise or exacerbation of respiratory failure, however. Abrupt postload elevation can lead to right heart failure, an indisputable indicator of prognosis. Because the symptoms of pulmonary hypertension are minimal relative to those of the chronic hypoxic lung disease, noninvasive diagnosis is difficult, particularly in patients with chronic obstructive pulmonary disease. Oxygen therapy (at least 16 h/day) is currently the best treatment for this type of pulmonary arterial hypertension.

[Physiological functional tests to evaluate pulmonary arterial hypertension]. / Explorations fonctionnelles dans l'hypertension artérielle pulmonaire.

INTRODUCTION: Pulmonary arterial hypertension (PAH) is a rare and complex disease, which requires careful diagnostic evaluation. STATE OF THE ART: Most patients have a mild decrease in lung volumes and a moderate decrease in carbon monoxide transfer factor. Mild to moderate arterial hypoxaemia, is often present, associated with a mild respiratory alkalosis. When hypoxaemia is severe, it may represent an intracardiac shunt. Right heart catheterisation is required to confirm the diagnosis and in most cases shows a significant elevation of pulmonary artery pressure due to an increase in pulmonary vascular resistance. The haemodynamic profile and the response to an acute pulmonary vasodilator challenge are determinants of prognosis. Finally, exercise capacity which is usually assessed by the six minute walk test provides an overall functional measure of disease severity, response to therapy, and progression. PERSPECTIVES: Functional evaluation of the heart using echocardiography will play an increasing role in the evaluation of PAH. CONCLUSIONS: Physiological measurements in PAH have several objectives. They form part of the diagnostic definition, allow the exclusion of other conditions and are tools for the assessment of severity, prognosis and response to therapy.

[Anemia caused by vitamin B 12 deficiency in subjects aged over 75 years: new hypotheses. A study of 20 cases]. / Anémies par carence en vitamine B12 chez le sujet âgé de plus de 75 ans: nouveaux concepts. A propos de 20 observations.

PURPOSE: New hypotheses have recently been developed on vitamin B12 deficiency and the frequently observed occurrence in the elderly subject of food cobalamin malabsorption, i.e., the non-dissociation of B12 and its carrier protein (ND B12), and the possibility of rectifying this imbalance by oral crystalline B12 supplementation. The aim of this study was therefore to confirm these hypotheses in a series of patients aged over 75 years with anemia due to B12 deficiency. METHODS: A retrospective study was carried out over a 5-year period on patients aged over 75 years presenting with megaloblastic anemia (hemoglobin [Hb] < 12 g/dL) and vitamin B12/cobalamin deficiency (B12 < 160 pg/mL). RESULTS: Twenty cases were analyzed. The average age of the patient population was 82.5 +/- 6 years, and the F/M sex ratio was 1:2. Mean Hb levels were 7.9 +/- 2.4 g/dL, mean serum B12 levels were 83 +/- 24 pg/mL, and mean homocysteinemic levels were 35 +/- 27 mumol/L. The diagnosis was as follows: food cobalamin malabsorption/ND B12 (n = 10), Biermer's disease/pernicious anemia (n = 5), malabsorption due to pancreatic insufficiency (n = 1), and low dietary B12 levels (n = 1). Disorders associated with ND B12 were: atrophic gastritis and Helicobacter pylori infection (n = 6), antacid or biguanide intake (n = 3), alcohol abuse (n = 2), or idiopathic syndrome (n = 2). In the patients who were followed up (n = 10), i.m. (n = 5) or oral (n = 5) administration of crystalline B12 resulted in the correction of hematological abnormalities. CONCLUSION: In the elderly subject, food cobalamin/ND B12 malabsorption appears to be the main cause of B12 deficiency, and is frequently associated with atrophic gastritis. In these cases, administration of oral crystalline B12 may be an efficient means of treating this disorder.