In patients with iron deficiency and symptomatic HFrEF, oral iron replacement improves exercise capacity. An inter atrial shunt device (IASD, Corvia Medical, Qp:Qs 1.2 to 1.3), can unload the LA in the setting of increased LA pressure (LAP), transferring the excess LA blood volume to the larger reservoir of the right atrium (RA) and systemic veins, leading to decrease in LAP, pulmonary venous pressures (PVP), pulmonary capillary wedge pressure (PCWP). This mechanistic effect should improve quality of life and exercise capacity in HFmEF / HFpEF patients.