Acute kidney injury in hypoplastic left heart syndrome patients following the comprehensive stage two palliation.

BACKGROUND: An alternative surgical approach for hypoplastic left heart syndrome is the Hybrid pathway, which delays the risk of acute kidney injury outside of the newborn period. We sought to determine the incidence, and associated morbidity, of acute kidney injury after the comprehensive stage 2 and the cumulative incidence after the first two operations in the Hybrid pathway. DESIGN: A single centre, retrospective study was conducted of hypoplastic left heart patients completing the second-stage palliation in the Hybrid pathway from 2009 to 2018. Acute kidney injury was defined utilising Kidney Diseases Improving Global Outcomes criteria. Perioperative and post-operative characteristics were analysed. RESULTS: Sixty-one patients were included in the study cohort. The incidence of acute kidney injury was 63.9%, with 36.1% developing severe injury. Cumulatively after the Hybrid Stage 1 and comprehensive stage 2 procedures, 69% developed acute kidney injury with 36% developing severe injury. The presence of post-operative acute kidney injury was not associated with an increase in 30-day mortality (acute kidney injury 7.7% versus none 9.1%; p = > 0.9). There was a significantly longer median duration of intubation among those with acute kidney injury (acute kidney injury 32 (8, 155) hours vs. no injury 9 (0, 94) hours; p = 0.018). CONCLUSIONS: Acute kidney injury after the comprehensive stage two procedure is common and accounts for most of the kidney injury in the first two operations of the Hybrid pathway. No difference in mortality was detected between those with acute kidney injury and those without, although there may be an increase in morbidity.

Incidence and impact of acute kidney injury in patients with hypoplastic left heart syndrome following the hybrid stage 1 palliation.

OBJECTIVE: Acute kidney injury leads to worse outcomes following paediatric cardiac surgery. There is a lack of literature focusing on acute kidney injury after the Hybrid stage 1 palliation for single ventricle physiology. Patients undergoing the Hybrid Stage 1, as a primary option, may have a lower incidence of kidney injury than previously reported. When present, kidney injury may increase the risk of post-operative morbidity and mortality. METHODS: A retrospective, single centre review was conducted in patients with hypoplastic left heart syndrome who underwent Hybrid Stage 1 from 2008 to 2018. Acute kidney injury was defined as a dichotomous yes (meeting any injury criteria) or no (no injury) utilising two different criteria utilised in paediatrics. The impact of kidney injury on perioperative characteristics and 30-day mortality was analysed. RESULTS: The incidence of acute kidney injury is 13.4-20.7%, with a severe injury rate of 2.4%. Patients without a prenatal diagnosis of hypoplastic left heart syndrome have a higher incidence of kidney injury than those prenatally diagnosed, (40% versus 14.5%, p = 0.024). Patients with acute kidney injury have a significantly higher incidence of 30-day mortality, 27.3%, compared to without, 5.6% (p = 0.047). DISCUSSION: The incidence of severe acute kidney injury after the Hybrid Stage 1 palliation is low. A prenatal diagnosis may be associated with a lower incidence of kidney injury following the Hybrid Stage 1. Though uncommon, severe acute kidney injury following Hybrid Stage 1 may be associated with higher 30-day mortality.

Tie a yellow ribbon around a papillary muscle.

An 8-year-old boy with tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collaterals status post complete repair including a fenestrated ventricular septal defect patch presented to the catheterization laboratory for fenestration closure. During the procedure, the catheterization wire was found to have an unusual intracardiac loop and was unable to be straightened within the heart. Three-dimensional transesophageal echocardiography revealed the wire was looped around a right ventricular papillary muscle. The wire was readjusted, and the fenestration was successfully closed. Three-dimensional imaging was essential in unambiguously defining the catheter course and assisting in fenestration closure.

Risk factors and prognostic significance of altered left ventricular geometry in preterm infants.

OBJECTIVE: Left ventricular (LV) hypertrophy (LVH) predicts adverse cardiac events in adults. We sought to determine the risk factors and prognostic significance of altered LV geometry in preterm infants. STUDY DESIGN: In an echocardiographic, single-center, retrospective case-control study we investigated the risk factors and outcomes in patients with altered LV geometry (either increased left ventricular mass index (LVMI) or increased relative wall thickness (RWT)) from a cohort of 503 preterm infants ≤2 kg. RESULT: Altered LV geometry was seen in 180 patients and was predicted by postnatal steroids and small for gestational age. Hospital stay was longer in the elevated RWT cases. Altered LV geometry resolved in 129 of the 131 cases with follow-up echocardiogram. Fifteen of 94 patients with elevated RWT died compared to 3/90 controls (P = 0.004). CONCLUSION: Altered LV geometry in preterm infants is associated with postnatal steroid use and small for gestational age. Elevated RWT is associated with longer hospital stay and increased mortality.

Normative Left Ventricular M-Mode Echocardiographic Values in Preterm Infants up to 2 kg.

BACKGROUND: There is a paucity of normative echocardiographic data in preterm infants. The objectives of this study were to (1) derive left ventricular (LV) M-mode reference values and (2) compare the performance of alternative methods of indexing LV dimensions and LV mass (LVM) in preterm infants. The authors propose that indexing LV measures to weight in preterm infants is a practical approach given the variability associated with tape-measure length measurement in infants. METHODS: In this retrospective study, LV M-mode echocardiographic measurements of end-diastolic interventricular septal thickness, end-diastolic LV posterior wall thickness, LV end-diastolic and end-systolic dimensions, LVM, and relative wall thickness were remeasured in 503 hospitalized preterm infants ≤2 kg (372 from a retrospective sample and 131 prospectively enrolled). Measures for all variables did not differ between retrospective and prospective samples, so results were pooled. LV dimensions and LVM indexed for weight, length, and body surface area sex-specific centile curves and corresponding Z scores were generated using Cole's lambda-mu-sigma method. Threshold limits (10th and 80th percentiles) were used to generate the normative range for relative wall thickness. RESULTS: Sex-specific centile curves using LVM, end-diastolic interventricular septal thickness, end-diastolic LV posterior wall thickness, LV end-diastolic dimension, and LV end-systolic dimension indexed to weight were similar to the curves generated using length and body surface area. The mean normal range for relative wall thickness was 0.33 (10th percentile, 0.26; 80th percentile, 0.38). CONCLUSIONS: From this large cohort of preterm infants, LV M-mode dimension and LVM centile curves indexed to weight were developed as a practical method to assess LV morphology in preterm infants.

Resource allocation in a social wasp: effects of breeding system and life cycle on reproductive decisions.

Organisms must make important decisions on how to allocate resources to reproduction. We investigated allocation decisions in the social wasp Vespula maculifrons to understand how social insects make reproductive choices. We first determined how annual colonies apportioned resources to growth and reproduction by analysing developing brood. In contrast to expectations, colonies invested in both growth (workers) and reproduction (males) simultaneously. In addition, colonies showed evidence of producing males in pulses and reversing their reproductive choices by decreasing investment in males late in the season. This reversal is consistent with theory suggesting that colonies decrease production in males if fitness of late emerging males is low. To further investigate reproductive decisions within colonies, we determined if the male mates of multiply-mated queens varied in their reproductive success over time. Sperm use by queens did vary over time suggesting that male success may depend on sperm clumping within the female reproductive tract. Finally, we tested if colony sex ratio conformed to expectations under kin selection theory that nestmate relatedness would positively correlate with investment in new queens if workers controlled sex allocation. Surprisingly, the proportion of queens produced by colonies was negatively correlated with nestmate relatedness, suggesting that allocation may be shaped by advantages arising from increased genetic diversity resulting from multiple mating by queens. Overall, our study suggests that the reproductive decisions of colonies are flexible and may depend both on environmental cues arising from energetic needs of the colony and genetic cues arising from mating behaviours of queens.