APLN and hydrops fetalis: Apelin treatment improved the diastolic function as evidenced by reduced EDP (16.19 ± 5.92 mmHg vs 25.65 ± 4.93 mmHg) and the slopes of the end-diastolic pressure-volume relationship (0.044 ± 0.003 mmHg/μl vs 0.056 ± 0.008 mmHgμl) and τ (10.42 ± 0.78 msec vs 13.91 ± 1.78 msec) whereas elevated -dP/dtmin (6746.29 ± 714.83 mmHg/s vs 5150.77 ± 629.05 mmHg/s) when compared to the untreated HF group.