ABSTRACT
Left heart disease is the most common cause of pulmonary hypertension (PH), referred to often as World Health Organization Group 2 PH. The mechanism responsible for the PH is transmission of elevations in left atrial pressure into the pulmonary circulation. In some patients due to either longstanding elevations in left atrial pressure and/or to certain genetic underpinnings, significant pulmonary vascular remodeling may occur resulting in PH with significantly elevated pulmonary vascular resistance (PVR). This entity is referred to as combined pre and post capillary pulmonary hypertension. The downstream consequences of PH are RV dysfunction and failure. Although echocardiography may suggest Group 2 PH, an invasive hemodynamic assessment is often necessary to confirm the diagnosis and to fully characterize its clinical impact and disease severity. The treatment of Group 2 PH is predicated on the treatment of left heart disease, including lowering of left atrial pressure. Targeted PH therapies have, to date, been associated with either no improvements or a worsening in clinical outcomes and are thus inadvisable. In advanced heart failure, severe PH with elevated PVR may preclude heart transplantation as a therapeutic option. However, durable ventricular assist devices lead to near complete resolution of clinically significant PH in most cases and may be used as an effective bridge to future cardiac transplantation strategy.
