Serum Cardiac Troponin I in the Evaluation of Nonaccidental Trauma.

OBJECTIVE: To determine if troponin I is more often elevated in children with suspected nonaccidental trauma (NAT) compared with uninjured children of similar age, and describe associations between troponin I elevation and NAT injuries. STUDY DESIGN: Prospective 2-group study of children less than 2 years of age presenting to the emergency department with nonaccidental abdominal, thoracic, or intracranial injuries, and similarly aged uninjured children. Primary outcome was serum troponin I (≥ 0.04 ng/mL) using frozen blood samples from the 2 groups. Secondary outcomes included descriptive analyses of age, injury characteristics, and clinical appearance. RESULTS: There were 129 subjects; 60 injured patients and 69 uninjured patients. Groups had similar age and sex. Troponin I was elevated in 38% of injured children compared with 17% of uninjured children (P = .008). No uninjured patient over 3 months of age had elevated troponin I. Abdominal trauma, acute rib fractures, or the child's ill-appearance in the emergency department were associated with having elevated troponin I. CONCLUSIONS: Troponin I is more often elevated in children with suspected NAT than uninjured children. Elevation of troponin I in children greater than 3 months of age with suspected NAT is concerning for trauma. Occult cardiac injury is more likely to occur in children with inflicted abdominal trauma, acute rib fractures, or ill appearance.

Revisiting animal models of aortic stenosis in the early gestation fetus.

BACKGROUND: Mechanisms leading to left ventricular hypoplasia and endocardial fibroelastosis in the fetus remain unknown. Prevailing theory is that obstruction to blood flow through the left ventricle leads to elevated end-diastolic pressures, compromised myocardial perfusion, and endocardial ischemia. Fetal interventions are now being performed, based on the presumption that they would prevent such pathogenic mechanisms. METHODS: Forty first-trimester fetal sheep (mean gestational age, 53 days) were studied. Severe fetal left ventricular outflow obstruction was created by banding the ascending aorta in 25 fetuses; 15 control fetuses underwent "sham" surgery with thoracotomy. Serial fetal echocardiography was used to assess left ventricular growth and fetal hemodynamics. Findings were correlated to morphologic and histopathologic changes, and intracardiac pressure measurements obtained from fetal cardiac catheterization. RESULTS: Surviving banded fetuses (n = 13) had one of two phenotypes: compensatory left ventricular hypertrophy (n = 7) or noncompensatory left ventricular dilatation (n = 6) with hydrops and severe left ventricular dysfunction. All fetuses had elevated left ventricular end-diastolic pressures (mean, 21 mm Hg; range, 14 to 28 mm Hg), which correlated to the gradient across the ascending aorta (mean, 41 mm Hg; range, 28 to 73 mm Hg). In vivo echocardiography findings were incongruous with those at autopsy, and demonstrated preservation of left ventricular growth indices in all fetuses. Endocardial fibroelastosis and myocardial fibrosis were not observed in any banded fetus. CONCLUSIONS: While early gestational obstruction to flow can compromise left ventricular function in the fetus, it does not retard normal growth. Similarly, an elevated left ventricular end-diastolic pressure is not sufficient to cause myocardial fibrosis or endocardial fibroelastosis in the fetus.