Kaashif A Ahmad | PubMed Health

PubMed2002

Blalock-Taussig shunt: experience from the developing world.

BACKGROUND: Palliative procedures have a role in congenital cardiac malformations that do not permit a complete early repair, and in centres where facilities for complete early repair do not exist. The lack of data on modified Blalock-Taussig shunt from developing countries prompted this analysis. METHODS: We report a retrospective study of 70 Blalock-Taussig shunt procedures in 63 patients over an 8-year period. Most of the procedures (54.0%) were done on children less than 4 months of age. Thirty-nine (58%) patients had Tetralogy of Fallot; the remaining patients had a wide spectrum of lesions. RESULTS: In the first year of the review period, the classical Blalock-Taussig shunt was done in six patients (9.5%) and the modified Blalock-Taussig shunt was used thereafter. In 49 patients who were followed up long term, clinical congestive cardiac failure developed in three (6%) and shunt failure was reported in 10 (14%). Of the 16 (33%) total deaths, six had serious comorbid conditions preoperatively. CONCLUSIONS: The Blalock-Taussig shunt is a relatively safe palliative procedure, requiring fewer resources and less expertise than corrective surgery, making it a suitable option in developing countries.

Journal Article↗

PubMedDate not supplied

Decreased liver hepcidin expression in the Hfe knockout mouse.

Hepcidin is a circulating antimicrobial peptide which has been proposed to regulate the uptake of dietary iron and its storage in reticuloendothelial macrophages. Transgenic mice lacking hepcidin expression demonstrate abnormalities of iron homeostasis similar to Hfe knockout mice and to patients with HFE-associated hereditary hemochromatosis (HH). To identify any association between liver hepcidin expression and the iron homeostasis abnormalities observed in HH, we compared liver hepcidin mRNA content in wild type and Hfe knockout mice. Because the iron homeostasis abnormalities in the Hfe knockout mice are greatest early in life, we analyzed mice at different ages. At four weeks of age, Hfe knockout mice had significantly decreased liver hepcidin mRNA expression compared to wild type mice. The decreased hepcidin expression was associated with hepatic iron deposition, elevated transferrin saturations, and decreased splenic iron concentrations. At 10 weeks of age, despite marked hepatic iron loading, Hfe knockout mice demonstrated liver hepcidin mRNA expression similar to that observed in wild type mice. Placing 8 week-old wild type and Hfe knockout mice on a 2% carbonyl iron diet for 2 weeks led to a similar degree of hepatic iron loading in each group. However, while the wild type mice demonstrated a mean five-fold increase in liver hepcidin mRNA, no change was observed in the Hfe knockout mice. The lack of an increase in liver hepcidin expression in these iron-loaded Hfe knockout mice was associated with sparing of iron deposition into the spleen. These data indicate that the normal relationship between body iron stores and liver hepcidin mRNA levels is altered in Hfe knockout mice, such that liver hepcidin expression is relatively decreased. We speculate that decreased hepcidin expression relative to body iron stores contributes to the iron homeostasis abnormalities characteristic of HH.

Animals↗