Piggyback mounting for stent and valve deployment during percutaneous pulmonary valve implantation.

OBJECTIVES: We report our experience in simultaneously implanting multiple stents and valves mounted on a single balloon before and during transcatheter pulmonary valve placement. BACKGROUND: Heterogeneity and complexity of the right ventricular outflow tract (RVOT) may complicate stent deployment when preparing a landing zone for transcatheter pulmonary valve implantation. METHODS: Retrospective analysis of patients from Children's Hospital of Colorado, USA; and Oslo University Hospital, Norway, undergoing transcatheter pulmonary valve replacement that had at least two stents mounted on a single balloon, deployed in the RVOT. RESULTS: Over a 42-month period, a total of 50 subjects from the two centers met inclusion criteria for the study. Subjects were predominantly male (58%), and the median age was 17 years (4-78 years). In six subjects (12%), there was need for prestenting with use of the double or triple stent piggyback technique. Forty subjects (80%) had a Melody ™ TPV implanted. In 45 cases (90%), one or more stents were mounted over the pulmonary valve using its delivery system, either the Ensemble for the Melody™ TPV or the Edwards Commander for the SAPIEN 3 THV. Thirty-seven subjects (74%) had one stent mounted and eight subjects (16%) had two stents mounted over the pulmonary valve for simultaneous deployment. No complications related to this technique were reported. CONCLUSIONS: The piggyback technique aims to simplify and facilitate adequate conduit preparation and valve insertion by minimizing manipulation across the outflow tract and decreasing the risk of stent distortion, misalignment, and embolization.

Transcriptome profiling of the newborn mouse brain after hypoxia-reoxygenation: hyperoxic reoxygenation induces inflammatory and energy failure responsive genes.

BACKGROUND: Supplemental oxygen used during resuscitation can be detrimental to the newborn brain. The aim was to determine how different oxygen therapies affect gene transcription in a hypoxia-reoxygenation model. METHODS: C57BL/6 mice (n = 56), postnatal day 7, were randomized either to 120 min of hypoxia 8% O2 followed by 30 min of reoxygenation with 21, 40, 60, or 100% O2, or to normoxia followed by 30 min of 21 or 100% O2. Affymetrix 750k expression array was applied with RT-PCR used for validation. Histopathology and immunohistochemistry 3 d after hypoxia-reoxygenation compared groups reoxygenated with 21 or 100% O2 with normoxic controls (n = 22). RESULTS: In total, ~81% of the gene expression changes were altered in response to reoxygenation with 60 or 100% O2 and constituted many inflammatory-responsive genes (i.e., C5ar2, Stat3, and Ccl12). Oxidative phosphorylation was downregulated after 60 or 100% O2. Iba1(+) cells were significantly increased in the striatum and hippocampal CA1 after both 21 and 100% O2. CONCLUSION: In the present model, hypoxia-reoxygenation induces microglial accumulation in subregions of the brain. The transcriptional changes dominating after applying hyperoxic reoxygenation regimes include upregulating genes related to inflammatory responses and suppressing the oxidative phosphorylation pathway.

N-Acetylcysteine Amide Exerts Possible Neuroprotective Effects in Newborn Pigs after Perinatal Asphyxia.

BACKGROUND: Perinatal asphyxia and ensuing reoxygenation change the antioxidant capacity of cells and organs. OBJECTIVES: To analyze the neuroprotective effect of the antioxidant N-acetylcysteine amide (NACA) after perinatal hypoxia-reoxygenation with an emphasis on proinflammatory cytokines and the transcription factor NF-κB in the prefrontal cortex of neonatal pigs. METHODS: Twenty-nine newborn pigs, aged 12-36 h, were subjected to global hypoxia and hypercapnia. One sham-operated group (n = 5) and 2 experimental groups (n = 12) were exposed to 8% oxygen, until the base excess was -20 mmol/l or the mean arterial blood pressure fell to <20 mm Hg (asphyxia with NACA or saline). The pigs were observed for 9.5 h after hypoxia. Samples of prefrontal cortex and plasma were analyzed. RESULTS: Cortex: there was no significant difference in mRNA expression between the intervention groups regarding IL-1ß, IL6, TNFα, MMP2, MMP9 or IL18. Pigs exposed to hypoxia-reoxygenation and treatment with NACA (NACA-pigs) had a significantly lower protein concentration of IL-1ß than pigs treated with saline (placebo controls), i.e. 8.8 ± 3.9 versus 16.8 ± 10.5 pg/mg protein (p = 0.02). The activation of the transcription factor NF-κB (measured as the fold-change of phosphorylated p65Ser 536), was reduced in the NACA-pigs when compared to the placebo controls (5.2 ± 4.3 vs. 16.0 ± 13.5; p = 0.02). No difference between the intervention groups regarding brain histopathology or in the levels of 8-oxoguanine measured in the prefrontal cortex were observed. Plasma: the NACA-pigs had a stronger reduction of TNFα in the first 30 min following asphyxia compared with the placebo controls, i.e. 36 (30-44) versus 24 (14-32)% (p = 0.01). CONCLUSION: The reduced levels of the pivotal inflammatory markers IL-1ß and TNFα and the transcription factor NF-κB may indicate that NACA has possible neuroprotective effects after perinatal asphyxia.