Effect of phototherapy on cardiac function in full term neonates with unconjugated hyperbilirubinemia

Abstract

Background: Phototherapy of jaundiced neonates has several cardiovascular effects. We investigated the effect of phototherapy on cardiac function in jaundiced full-term neonates using two-dimensional speckle tracking echocardiography (2D-STE).

Methods: This cohort study was conducted on 40 full term neonates with unconjugated hyperbilirubinemia who needed phototherapy as the patient group and 40 healthy neonates of matched gestational age, age, and sex served as the control group. Conventional echocardiography, tissue Doppler, and 2D-STE were performed before and 24 h after phototherapy. Serum troponin T, serum bilirubin levels, systolic and diastolic blood pressure, and heart rate (HR) were measured also before and after phototherapy.

Results: Systolic and diastolic blood pressure significantly decreased in the patient group after phototherapy compared to their levels before phototherapy. On the contrary, HR significantly increased after phototherapy in the patient group. However, serum cardiac troponin showed non-significant change after phototherapy. After phototherapy, all conventional and tissue Doppler parameters showed non-significant change. While 2D- left ventricular global longtudinal strain (2D-LVGLS) obtained by STE significantly decreased after phototherapy. There was a significant negative correlation between 2D-LV GLS and both duration and number of phototherapy units and both are good predictors for 2D-LVGLS.

Conclusion: Phototherapy may cause myocardial dysfunction that is correlated with the duration and number of phototherapy units.

Impact: Phototherapy of jaundiced neonates has many cardiovascular effects such as decrease in blood pressure and stroke volume. However, the effect of phototherapy on cardiac function in neonates has not been fully investigated yet. We investigated, for the first time, the effect of phototherapy on cardiac function in jaundiced full term neonates using two-dimensional speckle tracking echocardiography (2D-STE). Phototherapy may cause myocardial dysfunction that is correlated with the duration and number of phototherapy unit. Cardiac shield may be needed during phototherapy.