Normal Values of Atrioventricular Annular Velocities by Tissue Doppler Imaging in Egyptian Children

Abstract

Echocardiography is now the most commonly used non invasive tool for the assessment of cardiac anatomy and function. In addition to commonly established roles such as confirming diagnosis, etiologic work-up, complication screening, and disease monitoring, echocardiography plays an important clinical role in prognostic assessment (Yu et al., 2007). Tissue Doppler imaging (TDI) is a new echocardiographic technique well suited for the evaluation of longitudinal myocardial function, which is suspected to be initially affected in various cardiac diseases (Nikitin and Witte, 2004). Clinical studies haven shown that TDI provides diagnostic and prognostic information incremental to conventional echocardiography in some cardiac diseases (Nikitin et al., 2006). The aim of this study was to detect normal values of the mitral and tricuspid annular velocities measured by tissue Doppler imaging. In a large group of healthy children across a wide age range to establish their reference values and to assess the influence of age, sex and BSA. This study was conducted at the Echocardiography Unit, Pediatric Department at Ain Shams University, over the period from November 2013 to February 2015 on 250 healthy children without any known cardiovascular diseases. All children were subjected to detailed history taking laying stress on past medical history of clinical significance, family history of cardiovascular diseases in an early age and symptoms suggestive of any cardiovascular diseases. Thorough clinical examination laying stress on anthropometric measurements (height and weight), general physical examination including blood pressure assessment and local cardiac examination. ECG to exclude any cardiac electrical abnormalities, conventional 2D and Doppler echocardiography to detect any previously undiagnosed structural heart disease. Tissue Doppler imaging to detect the peak velocities of the systolic ,early and late diastolic excursion of the septal and lateral mitral annuli and the lateral tricuspid annulus ,and to calculate the modified myocardial performance index (Tei index) of both left and right ventricles. This study included 250 healthy children, their ages ranged from 22 days to 15 years. Males were 58% while females were 42% with male to female ratio 1.3:1.

The study population was divided into 6 representative age groups. Group 1 consisted of subjects from the neonatal period to1 year (13 child, 5.2 %); group 2 consisted of subjects aged above 1 to3 years (10 child, 4%); group 3 consisted of subjects aged above 3 to 6 years (87 child, 34.8%); group 4 consisted of subjects aged above 6 to 9 years (73 child, 29.2%); group 5 consisted of subjects aged above 9 to 12 years (45 child, 18%); and group 6 consisted of subjects aged above 12 to 15 years (22 child, 8.8%).