Biomonitors of cardiac injury and performance: B-type natriuretic peptide and troponin as monitors of hemodynamics and oxygen transport balance

Significance of detecting cardiac troponin I and creatine kinase MB in critically Ill children without primary cardiac illness

Objective

To investigate the incidence of myocardial injury in children with critically ill children without primary cardiac disease and the association between elevated cardiac troponin I (cTnl) and creatine kinase MB (CK-MB) concentrations and disease progression and prognosis to guide early treatment.

Methods

The serum cTnI and CK-MB concentrations of 292 children with critically ill children without primary cardiac disease in Yantai Yuhuangding Hospital between January 2021 and January 2024 were retrospectively analyzed within 24 h after entering the Pediatric Intensive Care Unit (PICU). The children were divided into normal and abnormal groups according to the myocardial marker results. The abnormal group was further divided into the cTnI-elevated, CK-MB-elevated, single-elevated (cTnI- or CK-MB-elevated) and double-elevated (cTnI- and CK-MB-elevated) groups. The differences in the clinical indicators and their relationships with prognosis for the groups were compared.

Results

The incidence of myocardial injury among the critically ill children without primary cardiac disease was 55.1%. The incidence of myocardial injury in children with infectious diarrhea combined with moderate and severe dehydration reached 85.19%. The pediatric critical illness score; frequency of use of vasoactive drugs; hypotension, shock, heart failure, respiratory failure, and multiple organ dysfunction syndrome; and mortality indexes differed significantly for the normal and abnormal myocardial marker groups (P < 0.05). The single-elevated and normal groups only showed a difference in mortality (P < 0.017). The cTnI and CK-MB concentrations were negatively correlated with prognosis (P < 0.01).

Conclusion

Myocardial injury, as evidenced by elevated cardiac biomarkers, is common in critically ill children without primary cardiac illness. cTnI and CK-MB are associated with outcomes. Shock, heart failure, and multiple organ dysfunction syndromes are independently associated with simultaneous elevations of CK-MB and cTnI concentrations. Further prospective studies are needed to elucidate the clinical utility of these biomarkers.

Beyond Conventional Hemodynamic Monitoring-Monitoring to Improve Our Understanding of Disease Process and Interventions

Monitoring the hemodynamic state of patients is a hallmark of any intensive care environment. However, no single monitoring strategy can provide all the necessary data to paint the entire picture of the state of a patient; each monitor has strengths and weaknesses, advantages, and limitations. We review the currently available hemodynamic monitors used in pediatric critical care units using a clinical scenario. This provides the reader with a construct to understand the progression from basic to more advanced monitoring modalities and how they serve to inform the practitioner at the bedside.

Effects of donor cause of death, ischemia time, inotrope exposure, troponin values, cardiopulmonary resuscitation, electrocardiographic and echocardiographic data on recipient outcomes: A review of the literature

BACKGROUND

Heart transplantation has become standard of care for pediatric patients with either end-stage heart failure or inoperable congenital heart defects. Despite increasing surgical complexity and overall volume, however, annual transplant rates remain largely unchanged. Data demonstrating pediatric donor heart refusal rates of 50% suggest optimizing donor utilization is critical. This review evaluated the impact of donor characteristics surrounding the time of death on pediatric heart transplant recipient outcomes.

METHODS

An extensive literature review was performed to identify articles focused on donor characteristics surrounding the time of death and their impact on pediatric heart transplant recipient outcomes.

RESULTS

Potential pediatric heart transplant recipient institutions commonly receive data from seven different donor death-related categories with which to determine organ acceptance: cause of death, need for CPR, serum troponin, inotrope exposure, projected donor ischemia time, electrocardiographic, and echocardiographic results. Although DITs up to 8 hours have been reported with comparable recipient outcomes, most data support minimizing this period to <4 hours. CVA as a cause of death may be associated with decreased recipient survival but is rare in the pediatric population. Otherwise, however, in the setting of an acceptable donor heart with a normal echocardiogram, none of the other data categories surrounding donor death negatively impact pediatric heart transplant recipient survival.

CONCLUSIONS

Echocardiographic evaluation is the most important donor clinical information following declaration of brain death provided to potential recipient institutions. Considering its relative importance, every effort should be made to allow direct image visualization.

Assessment of Myocardial Function and Injury by Echocardiography and Cardiac Biomarkers in African Children With Severe Plasmodium falciparum Malaria

OBJECTIVES

Perturbed hemodynamic function complicates severe malaria. The Fluid Expansion as Supportive Therapy trial demonstrated that fluid resuscitation, involving children with severe malaria, was associated with increased mortality, primarily due to cardiovascular collapse, suggesting that myocardial dysfunction may have a role. The aim of this study was to characterize cardiac function in children with severe malaria.

DESIGN

A prospective observational study with clinical, laboratory, and echocardiographic data collected at presentation (T0) and 24 hours (T1) in children with severe malaria. Cardiac index and ejection fraction were calculated at T0 and T1. Cardiac troponin I and brain natriuretic peptide were measured at T0. We compared clinical and echocardiographic variables in children with and without severe malarial anemia (hemoglobin < 5 mg/dL) at T0 and T1.

SETTING

Mbale Regional Referral Hospital.

PATIENTS

Children 3 months to 12 years old with severe falciparum malaria.

INTERVENTIONS

Usual care.

MEASUREMENTS AND MAIN RESULTS

We enrolled 104 children, median age 23.3 months, including 61 children with severe malarial anemia. Cardiac troponin I levels were elevated (> 0.1 ng/mL) in n equals to 50, (48%), and median brain natriuretic peptide was within normal range (69.1 pg/mL; interquartile range, 48.4-90.8). At T0, median Cardiac index was significantly higher in the severe malarial anemia versus nonsevere malarial anemia group (6.89 vs 5.28 L/min/m) (p = 0.001), which normalized in both groups at T1 (5.60 vs 5.13 L/min/m) (p = 0.452). Cardiac index negatively correlated with hemoglobin, r equals to -0.380 (p < 0.001). Four patients (3.8%) had evidence of depressed cardiac systolic function (ejection fraction < 45%). Overall, six children died, none developed pulmonary edema, biventricular failure, or required diuretic treatment.

CONCLUSIONS

Elevation of cardiac index, due to increased stroke volume, in severe malaria is a physiologic response to circulatory compromise and correlates with anemia. Following whole blood transfusion and antimalarial therapy, cardiac index in severe malarial anemia returns to normal. The majority (> 96%) of children with severe malaria have preserved myocardial systolic function. Although there is evidence for myocardial injury (elevated cardiac troponin I), this does not correlate with cardiac dysfunction.

Biomarkers in Pediatric Cardiac Critical Care

OBJECTIVES

In this review, we discuss the physiology, pathophysiology, and clinical role of troponin, lactate, and B-type natriuretic peptide in the assessment and management of children with critical cardiac disease.

DATA SOURCE

MEDLINE, PubMed.

CONCLUSION

Lactate, troponin, and B-type natriuretic peptide continue to be valuable biomarkers in the assessment and management of critically ill children with cardiac disease. However, the use of these markers as a single measurement is handicapped by the wide variety of clinical scenarios in which they may be increased. The overall trend may be more useful than any single level with a persistent or rising value of more importance than an elevated initial value.

Micro-RNA-208a, -208b, and -499 as Biomarkers for Myocardial Damage After Cardiac Surgery in Children

OBJECTIVES

To test the hypothesis that cardiac-enriched micro-RNAs can serve as accurate biomarkers that reflect myocardial injury and to predict the postoperative course following pediatric cardiac surgery. Micro-RNAs have emerged as plasma biomarkers for many pathologic states. We aimed to quantify preoperative and postoperative plasma levels of cardiac-enriched micro-RNA-208a, -208b, and -499 in children undergoing cardiac surgery and to evaluate correlations between their levels, the extent of myocardial damage, and the postoperative clinical course.

DESIGN

PICU.

PATIENTS

Thirty pediatric patients that underwent open heart surgery for the correction of congenital heart defects between January 2012 to July 2013.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

At 12 hours post surgery, the plasma levels of the micro-RNAs increased by 300- to 4,000-fold. At 24 hours, their levels decreased but remained significantly higher than before surgery. Micro-RNA levels were associated with troponin levels, longer cardiopulmonary bypass and aortic crossclamp times, maximal postoperative aspartate aminotransferase levels, and delayed hospital discharge.

CONCLUSIONS

Circulating micro-RNA-208a, -208b, and -499 are detectable in the plasma of children undergoing cardiac surgery and may serve as novel biomarkers for monitoring and forecasting postoperative myocardial injury and recovery.

Critical care for paediatric patients with heart failure

This review offers a critical-care perspective on the pathophysiology, monitoring, and management of acute heart failure syndromes in children. An in-depth understanding of the cardiovascular physiological disturbances in this population of patients is essential to correctly interpret clinical signs, symptoms and monitoring data, and to implement appropriate therapies. In this regard, the myocardial force-velocity relationship, the Frank-Starling mechanism, and pressure-volume loops are discussed. A variety of monitoring modalities are used to provide insight into the haemodynamic state, clinical trajectory, and response to treatment. Critical-care treatment of acute heart failure is based on the fundamental principles of optimising the delivery of oxygen and minimising metabolic demands. The former may be achieved by optimising systemic arterial oxygen content and the variables that determine cardiac output: heart rate and rhythm, preload, afterload, and contractility. Metabolic demands may be decreased by a number of ways including positive pressure ventilation, temperature control, and sedation. Mechanical circulatory support should be considered for refractory cases. In the near future, monitoring modalities may be improved by the capture and analysis of complex clinical data such as pressure waveforms and heart rate variability. Using predictive modelling and streaming analytics, these data may then be used to develop automated, real-time clinical decision support tools. Given the barriers to conducting multi-centre trials in this population of patients, the thoughtful analysis of data from multi-centre clinical registries and administrative databases will also likely have an impact on clinical practice.

Neonatal intensive care perspective

The hemodynamic evaluation and monitoring in the critically ill newborn (particularly the premature infant) poses unique challenges because of urgency, size limitations, and the persistence of fetal shunt channels. Echocardiography and other noninvasive methods are currently the mainstay of hemodynamic assessment. Evaluation of the hemodynamic significance of the arterial duct in the premature infant and cardiac performance in the near-term and term newborn with asphyxia, shock, and persistent pulmonary hypertension need to be more carefully refined, particularly assessments of left ventricular diastolic dysfunction. There is a need for evaluating a number of assessments as targets of goal-directed therapy in the unstable newborn infant. We provide an interpretation of the evidence supporting various monitoring strategies.