Mini Endoscopic Combined Intra-Renal Surgery (MiniECIRS) with endoview puncture in A 12 month boy. A safe but challenging procedure.

INTRODUCTION: Associating minipercutaneous nephrolithotomy and retrograde flexible ureteroscopy (fURS) is called Mini Endoscopic Combined Intra-Renal Surgery (miniECIRS). It's a safe and efficient technique, also in children. MATERIAL AND METHODS: The video describes miniECIRS in a 12 month-old boy with an infectious pelvic left stone (16 mm) and multiple caliceal stones. The UAS used was a 10FR and the percutaneous access was a 14Fr with Clear-Petra® sheath. RESULTS: The operative time was 180 min and blood losses were virtually absent. There were no intra- or post-operative complications and the patient was discharged at the 5th day. After 1 month, double J was removed having a stone free status. CONCLUSIONS: MiniECIRS with endoview puncture is a safe and efficient technique when performed by experienced hands. Therefore, it is an alternative to consider for the treatment of complex lithiasis in the pediatric population.

Genomic profiling of left and right ventricular hypertrophy in congenital heart disease.

BACKGROUND: The right ventricle (RV) has a lower ability than the left ventricle (LV) to adapt to systemic load. The molecular basis of these differences is not known. We compared hypertrophy-signaling pathways between the RV and the LV in patients with congenital heart disease (CHD). METHODS: Gene expression was measured using DNA microarrays in myocardium from children with CHD with LV or RV obstructive lesions undergoing surgery. The expression of 175 hypertrophy-signaling genes was compared between the LV (n=7) and the RV (n=11). Hierarchic clustering was performed. RESULTS: Seventeen genes (10%) were differentially expressed between the LV and the RV. Expression of genes for angiotensin, adrenergic, G-proteins, cytoskeletal, and contractile components was lower (P < .05) and expression of maladaptive factors (fibroblast growth factors, transforming growth factor-beta, caspases, ubiquitin) was higher in the RV compared with the LV (P < .05). Five of 7 LV samples clustered together. Only 4 of 11 RV samples clustered with the LV. Genes critical to adaptive remodeling correlated with the degree of LV hypertrophy but not RV hypertrophy. CONCLUSION: The transcription of pathways of adaptive remodeling was lower in the RV compared with the LV. This may explain the lower ability of the RV to adapt to hemodynamic load in CHD.

Failure of right ventricular adaptation in children with tetralogy of Fallot.

BACKGROUND: The left ventricle (LV) adapts to chronic hypoxia by expressing protective angiogenic, metabolic, and antioxidant genes to improve O2 delivery and energy production, and to minimize reoxygenation injury. The ability of the right ventricle (RV) to adapt to hypoxia in children with tetralogy of Fallot (TOF) is unknown. METHODS AND RESULTS: Gene expression using real-time polymerase chain reaction was measured in RV myocardium obtained during surgical repair of TOF from 23 patients: 13 cyanotic and 10 acyanotic. Results were compared between the 2 groups and correlated with age at surgery, severity of cyanosis, and early postoperative course. The cyanotic patients were younger at surgery compared with acyanotic (5+/-3 versus 9+/-4 months; P=0.01), had higher hematocrit (43+/-4 versus 38+/-3 grams/dL; P=0.004), and lower O2 saturations (84+/-4% versus 98+/-2%; (P<0.001). Cyanotic patients had a significantly lower expression of vascular endothelial growth factor (VEGF), glycolytic enzymes, and glutathione peroxidase (GPX) (P<0.05), and a higher expression of collagen (P<0.01) compared with acyanotic patients. Gene expression correlated inversely with severity of cyanosis ie, preoperative hematocrit (P<0.01) and positively with preoperative saturation (P<0.05). The relationship between gene expression and cyanosis was independent of age at surgery. Ca2+ handling genes did not correlate with the severity of hypoxia. Lower angiogenic, glycolytic, and antioxidant gene expression correlated with increasing postoperative lactate (P<0.05). CONCLUSIONS: The RV fails to up regulate adaptive pathways in response to increasing hypoxia in children with TOF. The implications of an early maladaptive response of the RV on long-term RV function require further investigation.

Impaired myocardial fatty acid oxidation and reduced protein expression of retinoid X receptor-alpha in pacing-induced heart failure.

BACKGROUND: The nuclear receptors peroxisome proliferator-activated receptor-alpha (PPARalpha) and retinoid X receptor alpha (RXRalpha) stimulate the expression of key enzymes of free fatty acid (FFA) oxidation. We tested the hypothesis that the altered metabolic phenotype of the failing heart involves changes in the protein expression of PPARalpha and RXRalpha. METHODS AND RESULTS: Cardiac substrate uptake and oxidation were measured in 8 conscious, chronically instrumented dogs with decompensated pacing-induced heart failure and in 8 normal dogs by infusing 3 isotopically labeled substrates: 3H-oleate, 14C-glucose, and 13C-lactate. Although myocardial O2 consumption was not different between the 2 groups, the rate of oxidation of FFA was lower (2.8+/-0.6 versus 4.7+/-0.3 micromol x min(-1) x 100g(-1)) and of glucose was higher (4.6+/-1.0 versus 1.8+/-0.5 micromol x min(-1) x 100g(-1)) in failing compared with normal hearts (P<0.05). The rates of lactate uptake and lactate output were not significantly different between the 2 groups. In left ventricular tissue from failing hearts, the activity of 2 key enzymes of FFA oxidation was significantly reduced: carnitine palmitoyl transferase-I (0.54+/-0.04 versus 0.66+/-0.04 micromol x min(-1) x g(-1)) and medium chain acyl-coenzyme A dehydrogenase (MCAD; 1.8+/-0.1 versus 2.9+/-0.3 micromol x min(-1) x g(-1)). Consistently, the protein expression of MCAD and of RXRalpha were significantly reduced by 38% in failing hearts, but the expression of PPARalpha was not different. Moreover, there were significant correlations between the expression of RXRalpha and the expression and activity of MCAD. CONCLUSIONS: Our results provide the first evidence for a link between the reduced expression of RXRalpha and the switch in metabolic phenotype in severe heart failure.

Reduced synthesis of NO causes marked alterations in myocardial substrate metabolism in conscious dogs.

To test whether the acute reduction of nitric oxide (NO) synthesis causes changes in cardiac substrate metabolism and in the activity of key enzymes of fatty acid and glucose oxidation, we blocked NOS by giving N(omega)-nitro-L-arginine methyl ester (L-NAME; 35 mg/kg iv two times) to nine chronically instrumented dogs. [3H]oleate, [14C]glucose, and [13C]lactate were infused to measure the rate of cardiac substrate uptake and oxidation. Glyceraldehyde-3-phosphate dehydrogenase, acetyl-CoA carboxylase, and malonyl-CoA decarboxylase activities were measured in myocardial biopsies. In eight control dogs, ANG II was infused (20-40 ng x kg(-1) x min(-1)) to mimic the hemodynamic effects of L-NAME. After L-NAME, significant changes occurred for fatty acid oxidation (from 9.8 +/- 0.8 to 7.1 +/- 1.2 micromol/min), glucose uptake (from 12.9 +/- 5.5 to 45.0 +/- 14.2 micromol/min), and oxidation (from 4.4 +/- 1.2 to 19.9 +/- 2.3 micromol/min). ANG caused only a significantly lower increase in glucose oxidation. Lactate uptake increased by more than twofold in both groups. The enzyme activities did not differ significantly between the two groups. In conclusion, the acute inhibition of NO synthesis causes marked metabolic alterations that do not involve key rate-controlling enzymes of fatty acid oxidation nor glyceraldehyde-3-phosphate dehydrogenase.