Elevated levels of NT-proBNP were an independent risk factor for CI-AKI in the HFrEF (OR 1.118, 95% CI 1.061–1.178; p value < 0.001), HFmrEF (OR 1.110, 95% CI 1.046–1.177; p value = 0.001) and HFpEF (OR 1.140, 95% CI 1.095–1.186, p < 0.001) groups (Fig. 4). This evidence concerns the gene NPPB and acute kidney injury.