Pulmonary hypertension in heart failure patients in the modern era of mechanical circulatory support.

Among patients with left-heart disease, pulmonary hypertension (PH) and right ventricular dysfunction are frequently present and associated with high mortality. An elevated pulmonary vascular resistance (PVR) ≥2.5 Wood units is associated with increased mortality after heart transplantation (HT). Although elevations in pulmonary pressures and resistance above established thresholds have been proposed as contraindications to HT, the risk associated with each parameter is increasing continuously from low to high values, and absolute cutoffs do not exist. An acute vasodilator challenge should be administered during right heart catheterization to document an acute reduction in the PVR to an acceptable level. The utilization of long-term left ventricular assist devices (LVADs) in end-stage heart failure has doubled in the past 10 years and continues to increase. Durable LVADs have been successfully used in patients with refractory elevated PVR. A reduction in PVR may be seen as early as 1 month post LVAD implantation; however, it may take 3 to 6 months to achieve maximum reversibility. Factors influencing the time needed to obtain a decrease in PVR are of great importance due to the implementation to medical practice of temporary axial pumps. The first experiences show that such a support may decrease PVR after weeks, enabling HT. Thus, we may postulate that temporary mechanical circulatory support in the near future will redefine our view of PH caused by left-heart disease. The current methods of assessing PH reversal may prohibit suitable candidates from being considered for HT. Using the new methods to assess PH reversal within a short time may be the key to improving long-term patient outcomes.