Incremental prognostic value of the hemodynamic gain index in patients undergoing exercise stress myocardial perfusion imaging.

Hemodynamic gain index showed negligible correlation with stress total perfusion deficit (total perfusion deficit) (ρ = 0.012, P = 0.675).

Adding hemodynamic gain index to a model containing stress total perfusion deficit improved model fit (Δχ 2 = 9.71, P = 0.002), C-index (ΔC-index = 0.006, P = 0.046), and continuous net reclassification improvement (0.310, P = 0.010).