Estimation of z-scores of cardiac structures in healthy children in Southeast Nigeria.

BACKGROUND

The z-scoring system shows the mean deviation of cardiac dimensions from age-specific population. The use of the European-based z-score studies has resulted in misdiagnosis and late treatment of Nigerian children with heart diseases leading to increased mortality and morbidity.

OBJECTIVES

This study aimed to determine the z‑scores for various cardiac structures and functions among healthy children in Southeast Nigeria.

MATERIALS AND METHODS

This is a cross-sectional observational study where z-scores of the cardiac structure and function of three hundred healthy children were estimated using echocardiography and compared with the standard Detroit values.

RESULT

There was a significant positive correlation between age and cardiac valve diameter. The aortic valve strongly correlated positively with age with the Pearson correlation coefficient (ρ) of 0.8 and probability value (P-value) of 0.00. None of the ventricular function variables deviated beyond the +2 or -2 z-score. There was a positive correlation between the z-scores of ventricular function parameters and participants' age, although the strength of the correlation varied. Comparing these values with that of Detroit values, there was a significant difference in the deviation of the mean of the mitral valve and left pulmonary artery diameters from the Detroit values between the males and the females. While the mean z-score mitral valve was 0.8 in males, it was 0.6 in females (P = 0.02).

CONCLUSION

Z-scores of cardiac structures and function are derived from children in this locale. These values were similar to that of Detroit values except for the mitral valve and left pulmonary artery.