Childhood obesity increases left-ventricular mass irrespective of blood pressure status

Adults with a left-ventricular mass index (LVMI) in grams normalized to height in meters(2.7) (LVMI g/m(2.7)) >51 g/m(2.7) are more prone to cardiovascular and cerebrovascular events. We delineated the odds for cardiac structural sequelae amongst apparently normal white and African-American (AA) children with varying body mass indices (BMI) and office blood pressures. A total of 2,071 children with normal echocardiograms were categorized into risk groups based on BMI and systolic blood pressures (SBPs). Predictors of cardiac sequelae examined were age, sex, race, and z-scores (z) for BMI, SBP, and diastolic blood pressure. Cardiac sequelae measures included (LVMI g/m(2.7)) >51 g/m(2.7), (LVMI) (g/m(2.7)) z, left atrial size (LA(ht)) (mm) z, and relative wall thickness z. Mean age was 14 ± 2 years with 56 % being male and 13 % being AA. Children were divided into "controls" (n = 1,059) and risk groups based on BMI and SBP. Odds ratio for LVMI (g/m(2.7)) > 51.0 g/m(2.7), varied from 5.3 up to 8.5 in children with increased BMI. Both increased BMI and SBP z were associated with increased LVMI (g/m(2.7)) z; however, BMI z had a stronger association. Increased BMI z and AA race were associated with greater LA(ht) (mm) z. AA controls had a nonsignificantly increased LVMI z and a significantly increased LA(ht) (mm) and RWT z. Being overweight or obese is associated with cardiac sequelae in children to the extent known to be associated with adverse outcomes in adults. Healthy AA children have unique cardiac structural differences.

Long-term survival after mitral valve replacement in children aged <5 years: a multi-institutional study

BACKGROUND

Short- and long-term outcomes after prosthetic mitral valve replacement (MVR) in children aged <5 years are ill-defined and generally perceived as poor. The experience of the Pediatric Cardiac Care Consortium (45 centers, 1982 to 1999) was reviewed.

METHODS AND RESULTS

MVR was performed 176 times on 139 patients. Median follow-up was 6.2 years (range 0 to 20 years, 96% complete). Age at initial MVR was 1.9+/-1.4 years. Complications after initial MVR included heart block requiring pacemaker (16%), endocarditis (6%), thrombosis (3%), and stroke (2%). Patient survival was as follows: 1 year, 79%; 5 years, 75%; and 10 years, 74%. The majority of deaths occurred early after initial MVR, with little late attrition despite repeat MVR and chronic anticoagulation. Among survivors, the 5-year freedom from reoperation was 81%. Age-adjusted multivariable predictors of death include the presence of complete atrioventricular canal (hazard ratio 4.76, 95% CI 1.59 to 14.30), Shone's syndrome (hazard ratio 3.68, 95% CI 1.14 to 11.89), and increased ratio of prosthetic valve size to patient weight (relative risk 1.77 per mm/kg increment, 95% CI 1.06 to 2.97). Age- and diagnosis-adjusted prosthetic size/weight ratios predicted a 1-year survival of 91% for size/weight ratio 2, 79% for size/weight ratio 3, 61% for size/weight ratio 4, and 37% for size/weight ratio 5.

CONCLUSIONS

Early mortality after MVR can be predicted on the basis of diagnosis and the size/weight ratio. Late mortality is low. These data can assist in choosing between MVR and alternative palliative strategies.

Effect of vitamin E on resistance vessel endothelial dysfunction induced by methionine

We tested if vitamin E, a fat-soluble antioxidant, prevents resistance vessel endothelial dysfunction caused by methionine-induced hyperhomocysteinemia in humans. Moderate elevations in plasma homocysteine concentrations are associated with atherosclerosis and hypertension. Homocysteine causes endothelial dysfunction possibly through several mechanisms. No previous study has tested if a fat-soluble antioxidant can prevent endothelial dysfunction caused by experimental hyperhomocysteinemia. Ten healthy subjects participated in a 2 x 2 factorial, double-blind crossover study, receiving L-methionine (100 mg/kg at -6 hours) or vehicle, with and without vitamin E (1,200 IU at -13 hours). Endothelial function of forearm resistance vessels was assessed using forearm blood flow responses to brachial artery administration of endothelium-dependent and endothelium-independent agents. Forearm resistance vessel dilatation to acetylcholine was significantly impaired 7 hours after methionine (placebo, 583 +/- 87% vs methionine 30 +/- 68%; p <0.05). Dilatation to bradykinin was also impaired (placebo, 509 +/- 54% vs methionine 289 +/- 48%; p <0.05). Methionine did not alter vasodilatation to the endothelium-independent vasodilators, nitroprusside, and verapamil. Methionine-induced impairment of resistance vessel dilatation to acetylcholine and bradykinin (p <0.05 vs placebo) was prevented by administration of vitamin E (acetylcholine, p = 0.004; bradykinin, p = 0.004; both vs methionine alone). Experimentally increasing plasma homocysteine concentrations by oral methionine rapidly impairs resistance vessel endothelial function in healthy humans and this effect is reversed with administration of the fat-soluble antioxidant, vitamin E.

Focal intestinal perforation in preterm infants is an emerging disease

In order to elicit the pathogenesis of focal intestinal perforation in preterm infants we contrasted 8 infants who developed this disease with 16 gestation-matched controls. The cases were found to have lower birthweights for gestation (median standard deviation score of -1.02 in cases versus -0.08 in controls), and more frequently had pre-existing patent ductus arteriosus and intraventricular haemorrhage (88 and 63% in cases versus 25 and 6% in controls, respectively). There were similar rates of other perinatal variables in the two groups, including indomethacin and umbilical arterial catheter use. Conditions associated with fetal or neonatal hypoxia are important antecedents for this emerging distinct clinical entity.

Perinatal deaths: relevance of Wigglesworth's classification

Out of a total of 4572 births over a period of 16 months occurring at St Philomena's Hospital, Bangalore, India, which has level II nursery facilities, there were 196 perinatal deaths. Perinatal mortality was 42.9/1000 total births. Case fatality rate was 12.4% for those born with a birthweight between 1501 to 2000 g, 35.5% for those between 1001 to 1500 g and 100% for those less than 1001 g. These deaths were grouped according to Wigglesworth's classification: 20% were due to prematurity and 24% to birth asphyxia. These two categories contributed to almost half of the perinatal deaths. Classification of perinatal deaths using Wigglesworth's classification appeared to be a practical and problem-oriented system. It also carried clear implications for improving perinatal care. The adoption of this method of classification by all major hospitals is recommended so that easy comparisons can be drawn over time and between different centres.