Transcatheter Implantation of Interatrial Shunt Devices to Lower Left Atrial Pressure in Heart Failure

Abstract

Patients with heart failure with preserved ejection fraction (HFpEF) constitutes a considerable sized population like that of subjects with heart failure with reduced ejection fraction. The symptoms include exercise induced dyspnoea and fatigue besides an increased mortality rate when compared to the general population. There is limited evidence of benefit from pharmacological therapy. A main pathophysiological mechanism is a left ventricular filling pressure that might be near to normal during resting conditions but increases during exercise leading to pulmonary congestion. Based on observations like the apparent lesser symptomatology in patients with combined mitral valve stenosis and atrial septal defect (Lutembacher syndrome) when compared to patients with isolated mitral valve stenosis, several Inter-Atrial Shunt Devices (IASD) have been developed with the intent to unload the pressure in the left atrium by creating a shunt into the right atrium. Smaller studies have found that the IASDs reduce the left ventricular filling pressure during exercise and increase the functional status of patients both subjectively and objectively with reported low rates of complications. These devices are undergoing further investigations and might prove to be a new paradigm in the treatment of patients with HFpEF.

Keywords: Haemodynamics; Heart failure; Investigatoinal therapies; Left ventricle.

Figure 1. Interatrial and coronary sinus-to let atrium shunt devices.

(A) IASD placement, shown the Occlutech atrial flow regulator. (B) Occlutech Atrial flow regulator. (C) Corvia. (D) First generation V-Wave. (E) Second generation V-Wave Ventura (valve-less). (F) Edwards Transcatheter Atrial Shunt System. IASD = inter-atrial shunt devices.