All types of heart failure are associated with reduced cardiac output and/or increased left atrial (LA) pressure. In diastolic heart failure (heart failure with preserved ejection fraction [HFpEF]), the increased LA pressure plays a central role, leading to pulmonary venous hypertension (PVH) and increased pulmonary artery pressure. These pressure parameters are presumably decisive for the symptoms and mortally of heart failure, particularly of the diastolic form. This is the basis for treatment with an interarterial shunt to reduce LA pressure in patients with diastolic heart failure and PVH. At first glance, this appears paradoxical, since closure of an atrial septum defect serves to prevent increased pulmonary vascular resistance and paradoxical embolism. Prevention of increased pulmonary vascular resistance and paradoxical embolism is thus an essential aspect in the development of devices for establishing an interarterial shunt. Reports on the InterAtrial Shunt Device (IASD®) and the V‑Wave have been published, both of which can be implanted with a low risk and few complications. The V‑Wave device is equipped with a valve to prevent paradoxical embolisms. However, paradoxical embolisms were also not observed with the IASD®, and the valve of the V‑Wave exhibited considerable degenerative changes and valve closure. Hemodynamic and clinical data of patients with an IASD® or an open V‑Wave device demonstrated a sustained hemodynamic improvement. Physical performance capacity and quality of life were increased. Whether IASD® may be broadly applicable in patients with diastolic heart failure is currently under investigation. In selected highly symptomatic patients with diastolic heart failure and PVH, the IASD® is already in clinal use.
Keywords: Embolism, paradoxical; Heart failure, diastolic, symptomatic; Hemodynamics; Patient safety; Pulmonary wedge pressure.