Abstract
Neurofibromatosis type 1 (NF1) is an autosomal dominant syndrome caused by mutations in the NF1 gene. Although cardiac abnormalities have been observed in NF1, they are frequently overlooked due to a lack of routine cardiac surveillance. Myocardial strain imaging offers a sensitive and non-invasive method for detecting early subclinical myocardial dysfunction. This study aims to detect cardiac abnormalities in children with NF1 using conventional echocardiography, Doppler tissue imaging (DTI), and myocardial strain analysis. A case-control study was conducted on 38 asymptomatic children with clinically confirmed NF1 and 35 healthy, age- and sex-matched controls. All patients underwent ECG, conventional echocardiography, DTI, and two-dimensional speckle-tracking echocardiography. NF1 patients showed significantly decreased ejection fraction (p = 0.0009) and higher interventricular septal and posterior wall thickness during systole (p < 0.0001). DTI revealed reduced mitral systolic (Sm) and early diastolic (Em) velocities, longer isovolumic contraction and relaxation periods, and increased LV Tei index values (p < 0.0001), indicating combined systolic and diastolic dysfunction. Also, myocardial strain analysis in NF1 children revealed considerably lower peak systolic left ventricular global longitudinal strain (LVGLS) (p 0.0014), as well as lower peak systolic septal and lateral wall strain values (p 0.0046, 0.0027), respectively. Conclusion: Children with NF1 show early subclinical myocardial dysfunction, even when there is no hypertension or overt cardiac symptoms. These findings highlight the significance of frequent echocardiographic screening, including strain imaging, for the early diagnosis and longitudinal monitoring of heart function in NF1 children. What is Known: • Neurofibromatosis type 1 (NF1) is a multisystem syndrome that can involve the cardiovascular system. • Previous studies showed hypertrophic cardiac changes in NF1 patients, but data in children, especially those without hypertension, are limited, as routine echocardiography is not involved in NF1 management. What is New: • Our study revealed early subclinical myocardial dysfunction in NF1 children without the presence of hypertension or overt cardiac symptoms. • This emphasizes the potential of myocardial strain imaging as a sensitive tool for early detection of myocardial dysfunction in NF1 children, thereby supporting the need for routine echocardiographic surveillance in these patients.