Right ventricular failure (RVF) remains a common complication in patients with pulmonary hypertension (PH), regardless of the etiology of elevated pulmonary pressures. Normally, the RV stroke work, which is 1/6th compared to that of the LV, maintains forward momentum of blood flow into highly compliant, low resistant pulmonary circulation. Therefore, the RV flow is characterized by low peak systolic pressure in absence of isovolumetric phases of contraction and relaxation during systole and diastole. Unfortunately, patients with pulmonary arterial hypertension (PAH) or left heart disease commonly develop secondary RVF. Mechanisms of RVF include: contractile failure secondary to myocardial ischemia, volume overload (preload) as a result of right-sided valvular insufficiency, displacement of the ventricular septum towards the LV and increase in RV afterload. Close monitoring of pulmonary artery pressure and RV function is necessary to appropriately guide therapy and predict survival. The development of ambulatory implantable hemodynamic monitors such as CardioMEMS provides clinicians with remote access to daily cardiovascular measurements to monitor progression, guide therapy, and detect or prevent early decompensation. They do so by allowing clinicians to review the RV functional response at rest and with exertion, in response to therapy. CardioMEMS sensors are implanted in the pulmonary artery and calibrated with pulmonary pressure and cardiac output, based on the PAP waveform, heart rate, and a reference cardiac output measured at implant. We will review the pathophysiology of RVF failure in left heart disease and PAH and discuss the role of implantable monitors in guiding positive remodeling of the RV in these disease conditions.