Prognostic value of troponin in infants with hypoplastic left heart syndrome between Stage I and II of palliation

Hypoplastic Left Heart Syndrome with Mitral Stenosis and Aortic Atresia-Echocardiographic Findings and Early Outcomes

BACKGROUND

Mitral stenosis/aortic atresia (MS/AA) has been reported as a high-risk variant of hypoplastic left heart syndrome (HLHS), potentially related to ventriculocoronary connections (VCCs) or endocardial fibroelastosis (EFE) and myocardial hypoperfusion. We aimed to identify echocardiographic and clinical factors associated with early death or transplant in this group.

METHODS

Patients with HLHS MS/AA treated at our center between 2000 and 2020 were included. Pre-stage I palliation echocardiograms were reviewed. Certain imaging factors, such as determination of VCC, EFE, and measurement of tricuspid annular plane systolic excursion were measured from retrospective review of preoperative images; others were derived from clinical reports. Groups were compared according to primary outcome of death or transplant prior to stage II palliation.

RESULTS

Of 141 patients included, 39 (27.7%) experienced a primary outcome. Ventriculocoronary connections were identified in 103 (73.0%) patients and EFE in 95 (67.4%) patients. Among imaging variables, smaller ascending aorta size (median, 2.2 [interquartile range (IQR) 1.7-2.8] vs 2.6 [2.2-3.4] mm, P = .01) was associated with primary outcome. There was similar frequency of VCC (74.4% vs 72.5%, P = .83), EFE (59.0% vs 72.5%, P = .19), moderate or greater tricuspid regurgitation (5.1% vs 5.9%, P = 1.00), and similar right ventricular systolic function (indexed tricuspid annular plane systolic excursion 32.5 ± 7.3 vs 31.4 ± 7.2 mm/m2, P = .47) in the primary outcome group compared to other patients. Clinical factors associated with primary outcome included lower birth weight (mean, 2.8 ± SD 0.8 vs 3.3 ± 0.5 kg, P = .0003), gestational age <37 weeks (31.6% vs 4.9%, P < .0001), longer cardiopulmonary bypass time (median, 112 [IQR, 93-162] vs 82 [71-119] minutes, P = .001), longer intensive care unit length of stay (median, 19 [IQR, 10-30] vs 10 [7-15] days, P = .001), and extracorporeal membrane oxygenation following stage I palliation (43.6% vs 8.8%, P < .0001). Presence of VCCs and EFE was not associated with death or transplant after controlling for birth weight and era of stage I palliation.

CONCLUSIONS

In one of the largest reported single-center cohorts of HLHS MS/AA, there were few pre-stage I palliation imaging characteristics associated with primary outcome. Imaging findings evaluated in this study, including the presence of VCC and/or EFE as determined using highly sensitive echocardiogram criteria, should not preclude intervention, although impact on long-term outcomes requires further evaluation.

High-Sensitivity Cardiac Troponin and the Management of Congenital Heart Disease in Newborns and Infants

BACKGROUND

Early cardiac interventions in newborns and infants suspected for congenital heart disease (CHD) decrease morbidity and mortality. After updating current evidence on the use of cardiac troponins (cTn) in the context of CHD for risk stratification at early ages, we discuss relevant issues, starting from the evidence that only the measurement of the cTnT form is useful in this population.

CONTENT

In newborns/infants with CHD, the cTnT concentration increase is correlated with: (a) cardiac stress and hemodynamic parameters, but not with the type of CHD; (b) volume overload/right ventricular pressure overload; (c) postoperative hypoperfusion injury and mortality; and (d) effects of cardioprotective strategies. For infants with CHD, high-sensitivity cTnT (hs-cTnT) concentrations >25 ng/L are an independent predictor of poor outcomes. Transitioning from cTnT to hs-cTnT in newborns/infants improves the identification of: (a) physiopathological mechanisms and factors that increased hs-cTnT early after birth; (b) myocardial injury, even when subclinical; (c) identification of patients requiring immediate therapeutic interventions; and (d) 99th percentile upper reference limits (URLs). However, no reliable URLs are currently available to allow the detection of myocardial injury associated with CHD in newborns/infants.

SUMMARY

Additional data evaluating the clinical value of hs-cTnT in the risk stratification of newborns/infants with CHD who may suffer myocardial injury is needed. Validating the measurement, possibly in amniotic fluid samples, and improving the interpretation of hs-cTnT concentrations in the prenatal period, at birth and within 1 year of age are crucial to change CHD mortality/morbidity trends in the pediatric population.

Postoperative Troponin Levels in Children Undergoing Open Heart Surgery With and Without Coronary Intervention

We aimed to characterize the ranges, temporal trends, influencing factors, and prognostic significance of postoperative troponin levels after congenital heart surgery. This single-center retrospective study included patients from 2006 to 2021 who had ≥ 1 postoperative troponin-T measurement collected within 96 h of congenital heart surgery (CHS). Patients were grouped as Anomalous Aortic Origin of the Coronary Artery-"AAOCA repair," or congenital heart surgery with "Other Coronary Interventions" other than AAOCA repair, or "No Coronary Intervention." In each group, information on concomitant surgery requiring one or more of the following-atriotomy, ventriculotomy, right ventricular muscle bundle resection, and/or septal myectomy-was collected. Clinical correlates of troponin values were analyzed in three postoperative windows: < 8, 8-24, and 24-48 h. The highest median [range] troponin levels (ng/mL) for the samples were 0.34 [0.06, 1.32] at < 8 h for "AAOCA repair," 1.35 [0.14, 12.0] at < 8 h for those undergoing CHS with "Other Coronary Interventions," and 0.87 [0.06, 25.1] at 8-24 h for those undergoing CHS with "No Coronary Interventions." Atriotomy was associated with higher median troponin levels in the AAOCA group at < 8 h (0.40 [0.31, 0.77] vs. 0.29 [0.17, 0.54], P = 0.043) and in the Other Coronary Intervention group at 8-24 h (1.67 [1.04, 2.63] vs. 0.40 [0.19, 1.32], P = 0.002). Patients experiencing major postoperative complications (vs. those who did not) had higher troponin levels in the AAOCA group as early as 8-24 h (0.36 [0.24, 0.57] vs. 0.21 [0.14, 0.33], P = 0.03). Similar findings were noted in the Coronary Intervention (2.20 [1.34, 3.90] vs. 1.11 [0.51, 2.90], P = 0.028) and No Coronary Intervention (2.2 [1.49, 15.1] vs. 0.74 [0.40, 2.34], P = 0.027) groups but earlier at < 8 h. In the AAOCA group, 2/18 (11%) troponin outliers experienced cardiac arrest in comparison to 0/80 (0%) non-outliers (P = 0.032). In the Other Coronary Intervention group, troponin outliers had longer median times to ICU discharge (10 vs. 4 days) and hospital discharge (21 vs. 10 days) (both P < 0.001). Postoperative troponin levels depend on a multitude of factors and may have prognostic value in patients undergoing congenital heart surgery with coronary interventions.

Association between Serum Lactate and Morbidity and Mortality in Neonates: A Systematic Review and Meta-Analysis

OBJECTIVE

Lactate is a marker of hypoperfusion in critically ill patients. Whether lactate is useful for identifying and stratifying neonates with a higher risk of adverse outcomes remains unknown. This study aimed to investigate the association between lactate and morbidity and mortality in neonates.

METHODS

A meta-analysis was performed to determine the association between blood lactate levels and outcomes in neonates. Ovid MEDLINE, EMBASE, Cochrane Library, and ClinicalTrials.gov were searched from inception to 1 May 2021. A total of 49 observational studies and 14 data accuracy test studies were included. The risk of bias was assessed using the Newcastle-Ottawa Scale for observational studies and the QUADAS-2 tool for data accuracy test studies. The primary outcome was mortality, while the secondary outcomes included acute kidney injury, necessity for renal replacement therapy, neurological outcomes, respiratory morbidities, hemodynamic instability, and retinopathy of prematurity.

RESULTS

Of the 3184 articles screened, 63 studies fulfilled all eligibility criteria, comprising 46,069 neonates. Higher lactate levels are associated with mortality (standard mean difference, -1.09 [95% CI, -1.46 to -0.73]). Using the estimated sensitivity (0.769) and specificity (0.791) and assuming a prevalence of 15% for adverse outcomes (median of prevalence among studies) in a hypothetical cohort of 10,000 neonates, assessing the lactate level alone would miss 346 (3.46%) cases (false negative) and wrongly diagnose 1776 (17.76%) cases (false positive).

CONCLUSIONS

Higher lactate levels are associated with a greater risk of mortality and morbidities in neonates. However, our results do not support the use of lactate as a screening test to identify adverse outcomes in newborns. Research efforts should focus on analyzing serial lactate measurements, rather than a single measurement.