A Uniform Description of Perioperative Brain MRI Findings in Infants with Severe Congenital Heart Disease: Results of a European Collaboration

BACKGROUND AND PURPOSE

A uniform description of brain MR imaging findings in infants with severe congenital heart disease to assess risk factors, predict outcome, and compare centers is lacking. Our objective was to uniformly describe the spectrum of perioperative brain MR imaging findings in infants with congenital heart disease.

MATERIALS AND METHODS

Prospective observational studies were performed at 3 European centers between 2009 and 2019. Brain MR imaging was performed preoperatively and/or postoperatively in infants with transposition of the great arteries, single-ventricle physiology, or left ventricular outflow tract obstruction undergoing cardiac surgery within the first 6 weeks of life. Brain injury was assessed on T1, T2, DWI, SWI, and MRV. A subsample of images was assessed jointly to reach a consensus.

RESULTS

A total of 348 MR imaging scans (180 preoperatively, 168 postoperatively, 146 pre- and postoperatively) were obtained in 202 infants. Preoperative, new postoperative, and cumulative postoperative white matter injury was identified in 25%, 30%, and 36%; arterial ischemic stroke, in 6%, 10%, and 14%; hypoxic-ischemic watershed injury in 2%, 1%, and 1%; intraparenchymal cerebral hemorrhage, in 0%, 4%, and 5%; cerebellar hemorrhage, in 6%, 2%, and 6%; intraventricular hemorrhage, in 14%, 6%, and 13%; subdural hemorrhage, in 29%, 17%, and 29%; and cerebral sinovenous thrombosis, in 0%, 10%, and 10%, respectively.

CONCLUSIONS

A broad spectrum of perioperative brain MR imaging findings was found in infants with severe congenital heart disease. We propose an MR imaging protocol including T1-, T2-, diffusion-, and susceptibility-weighted imaging, and MRV to identify ischemic, hemorrhagic, and thrombotic lesions observed in this patient group.

Rapidly progressive hypertrophic cardiomyopathy in an infant with Noonan syndrome with multiple lentigines: palliative treatment with a rapamycin analog

Noonan syndrome with multiple lentigines (NSML) frequently manifests with hypertrophic cardiomyopathy (HCM). Recently, it was demonstrated that mTOR inhibition reverses HCM in NSML mice. We report for the first time on the effects of treatment with a rapamycin analog in an infant with LS and malignant HCM. In the boy, progressive HCM was diagnosed during the first week of life and a diagnosis of NSML was established at age 20 weeks by showing a heterozygous Q510E mutation in PTPN11. Immunoblotting with antibodies against pERK, pAkt, and pS6RP in fibroblasts demonstrated enhanced Akt/mTOR pathway activity. Because of the patient's critical condition, everolimus therapy was started at age 24 weeks and continued until heart transplantation at age 36 weeks. Prior to surgery, heart failure improved from NYHA stage IV to II and brain natriuretic peptide values decreased from 9,600 to <1,000 pg/ml, but no reversal of cardiac hypertrophy was observed. Examination of the explanted heart revealed severe hypertrophy and myofiber disarray with extensive perivascular fibrosis. These findings provide evidence that Akt/mTOR activity is enhanced in NSML with HCM and suggest that rapamycin treatment could principally be feasible for infantile NSML. The preliminary experiences made in this single patient indicate that therapy should start early to prevent irreversible cardiac remodelling.