Tratamiento nutricional del fallo intestinal y potenciales mecanismos de estimulación.

Severe forms of intestinal failure represent one of the most complex pathologies to manage, in both children and adults. In adults, the most common causes are chronic intestinal pseudo-obstruction and severe short bowel syndrome following large intestinal resections, particularly due to massive mesenteric ischemic, within the context of cardiopathies occurring with atrial fibrillation. The essential management after stabilizing the patient consists in nutritional support, either by parenteral or enteral routes, with tolerance to oral diet being the final goal of intestinal adaptation in these pathologies. Surgery may be indicated in some cases to increase the absorptive surface area. Parenteral nutrition is an essential support measure that sometimes has to be maintained for long time, even forever, except for technique-related complications or unfavorable clinical course that would lead to extreme surgical alternatives such as intestinal transplantation. Hormonal therapy with trophism-stimulating factors opens new alternatives that are already being tried in humans.

Nutrición, fibrosis quística y aparato digestivo

The prevalence of hyponutrition in cystic fibrosis is high although it may vary according to the different studies. Detection of hyponutrition should be done by combining different methods, depending on their availability. However, the simplest and most validated criterion is to measure at each visit the weight (and height in children) in order to calculate the body mass index and categorizing hyponutrition according to absolute criteria: in adults < 18.5 kg/m(2), and in children as percentiles of the body mass index. Worsening of the nutritional status is directly related with the decrease in lung function parameters and it has been proposed as a morbidity (and even mortality) predictive factor in people with cystic fibrosis, independently of the level of pulmonary dysfunction. Exocrine pancreatic insufficiency is present is approximately 70-90% of the patients with cystic fibrosis and the genotype-phenotype correlation is high. Most of the patients with exocrine pancreatic insufficiency tolerate a high-fat diet provided that they are treated with pancreatic enzymes at appropriate doses. The prevalence of diabetes increases with age, reaching up 40% of the cases in patients older than 30 years. Clinical liver involvement is less prevalent (it approximately affects 1/3 of the patients). Other intestinal complications such as meconial ileus, gastroesophageal reflux, obstruction of the distal intestine, or fibrosing colon disease may also condition malnourishment. In patients with cystic fibrosis, a usual high-fat diet providing 120%-150% of the recommended calories is advised. If the nutritional goals are not achieved or maintained with diet modifications, artificial supplements may be added, although the recommendation for their use has not been endorsed by solid scientific evidences. The most frequently used preparations usually are polymeric or hypercaloric. The indications for enteral (through a tube, especially gastrostomy) or parenteral nutritional support are similar to those used in other pathologies. Dietary and nutritional control should be included in a multidisciplinary program allowing the improvement of the functional capacity and the quality of life and reducing, at least from a theoretical viewpoint, the morbimortality associated to malnourishment in these patients.

Transcatheter aortic valve replacement for degenerative bioprosthetic surgical valves: Results from the global valve-in-valve registry.

BACKGROUND Transcatheter aortic valve-in-valve implantation is an emerging therapeutic alternative for patients with a failed surgical bioprosthesis and may obviate the need for reoperation. We evaluated the clinical results of this technique using a large, worldwide registry. METHODS AND RESULTS The Global Valve-in-Valve Registry included 202 patients with degenerated bioprosthetic valves (aged 77.7±10.4 years; 52.5% men) from 38 cardiac centers. Bioprosthesis mode of failure was stenosis (n=85; 42%), regurgitation (n=68; 34%), or combined stenosis and regurgitation (n=49; 24%). Implanted devices included CoreValve (n=124) and Edwards SAPIEN (n=78). Procedural success was achieved in 93.1% of cases. Adverse procedural outcomes included initial device malposition in 15.3% of cases and ostial coronary obstruction in 3.5%. After the procedure, valve maximum/mean gradients were 28.4±14.1/15.9±8.6 mm Hg, and 95% of patients had ≤+1 degree of aortic regurgitation. At 30-day follow-up, all-cause mortality was 8.4%, and 84.1% of patients were at New York Heart Association functional class I/II. One-year follow-up was obtained in 87 patients, with 85.8% survival of treated patients. CONCLUSIONS The valve-in-valve procedure is clinically effective in the vast majority of patients with degenerated bioprosthetic valves. Safety and efficacy concerns include device malposition, ostial coronary obstruction, and high gradients after the procedure.

Comprehensive analysis of NRG1 common and rare variants in Hirschsprung patients.

Hirschsprung disease (HSCR, OMIM 142623) is a developmental disorder characterized by the absence of ganglion cells along variable lengths of the distal gastrointestinal tract, which results in tonic contraction of the aganglionic gut segment and functional intestinal obstruction. The RET proto-oncogene is the major gene for HSCR with differential contributions of its rare and common, coding and noncoding mutations to the multifactorial nature of this pathology. Many other genes have been described to be associated with the pathology, as NRG1 gene (8p12), encoding neuregulin 1, which is implicated in the development of the enteric nervous system (ENS), and seems to contribute by both common and rare variants. Here we present the results of a comprehensive analysis of the NRG1 gene in the context of the disease in a series of 207 Spanish HSCR patients, by both mutational screening of its coding sequence and evaluation of 3 common tag SNPs as low penetrance susceptibility factors, finding some potentially damaging variants which we have functionally characterized. All of them were found to be associated with a significant reduction of the normal NRG1 protein levels. The fact that those mutations analyzed alter NRG1 protein would suggest that they would be related with HSCR disease not only in Chinese but also in a Caucasian population, which reinforces the implication of NRG1 gene in this pathology.

Transaortic Fallot repair in a grown-up patient: advantages in a situs inversus setting.

We present the case studies of two adult patients with tetralogy of Fallot who were scheduled for surgery. After addressing the right ventricular outflow tract obstruction, the aorta was opened and the ventricular septal defect was approached in a straightforward manner as it was located just under the overriding aortic valve. The second patient presented with was a situs inversus, dextroapex Fallot. In this setting, the aortic approach simplified the repair expeditiously. After 2 years, both patients are in New York Heart Association class I, with no residual ventricular septal defect, no aortic regurgitation, and complete relief of right ventricular outflow tract obstruction.