Melatonin Improves Heart Function in Newborns with Severe Lung Hypertension

Persistent Pulmonary Hypertension of the Newborn (PPHN) is a life-threatening condition where a newborn's circulatory system fails to adapt to extrauterine life, leading to high blood pressure in the lung arteries and often impacting heart function. This can result in significant morbidity and mortality due to inadequate oxygenation and strain on the heart, particularly the left ventricle. Current treatments are often insufficient, highlighting an urgent need for novel therapeutic strategies. This study investigates the specific effects of melatonin administration on left ventricular function in neonates diagnosed with PPHN.

The study found that melatonin significantly improved left ventricular function in neonates with PPHN. At the end of the 7-day treatment period, the melatonin group showed a mean LVEF of 62.5% (±3.1%), a 17.5% absolute increase from their baseline of 45%, compared to the placebo group which only increased to 47.2% (±2.8%), a 2.2% absolute increase from baseline (p<0.001). Similarly, Fractional Shortening (FS) improved by 12.8% absolute in the melatonin group (from 24% to 36.8%) versus only 1.5% absolute in the placebo group (p<0.001). The most significant finding was that melatonin treatment led to a 38.9% relative improvement in LVEF compared to baseline, whereas the placebo group showed only a 4.9% relative improvement, demonstrating a substantial therapeutic effect. Furthermore, the melatonin group experienced a 25% reduction in mean pulmonary artery pressure, alongside a 30% improvement in oxygenation index (a measure of lung function), both significantly better than the control group (p<0.01 for both). No significant adverse events were reported in either group.