Clinical findings associated with normal echocardiographic results in newborns hospitalized in a high-altitude center.

Abstract

Introduction: Congenital heart defects occur in 4 to 10 per 1000 live births and represent about 10 % of infant deaths. Currently, few clinical findings suggest an abnormal echocardiogram, so screening tests such as pulse oximetry are used, but there are doubts about their accuracy in high-altitude cities. Objective: To determine the relationship between the clinical findings of newborns hospitalized in a high-altitude unit and their echocardiographic findings. Methods: Cross-sectional historical study. Patients under 28 days of age underwent an echocardiogram as part of the diagnostic approach between May 2017 and January 2020. Clinical variables were compared with echocardiographic findings using bivariate and logistic regression. Results: 849 patients with a median age of 4 days and 36 weeks of gestational age were included. Five newborns (0.6 %) showed heart disease with critical defects, 25.2 % had non-critical defects (74.9 % had patent ductus arteriosus greater than 2mm, 13.2 % atrial septal defect greater than 5mm, and 11.7 % pulmonary hypertension), and in 74.4 % it was normal. When performing the multivariate model, having ≤7 days of life (OR 2.1, 95 % CI [1.22-3.34]), FiO2 >35 % (OR 2.02, 95 % CI [1.42-2.86]), heart murmur (OR 3.34, 95 % CI [2.01-5.57]), associated malformation (OR 2.35 95 % CI [1.54-3.58]), feeding difficulties (OR 1.57, 95 % CI [1.07-2.31]) and abnormal chest X-ray (OR 1.54, 95 % CI [1.04-2.31]), behaved as independently associated factors for the presence of an abnormal echocardiogram. Conclusions: This study detected some findings associated with normal echocardiograms that could help create a predictive model for patients at high altitudes to improve the performance of screening tests developed at sea level.