Unrecognized Left Heart Failure in LVAD Recipients: The Role of Routine Invasive Hemodynamic Testing.

Abstract

The role of routine right heart catheterizations (RHCs) in left ventricular assist device (LVAD) patients is undefined. We analyzed 105 continuous-flow LVAD recipients who underwent an RHC approximately 3 months after implant. In 38 patients, LVAD speed was ramped with the goal of optimizing hemodynamics. Our cohort consisted of 71 (68%) HeartMate II (HMII) and 34 (32%) HeartWare (HVAD) patients. Thirty patients (29%) had either a reduced cardiac index (CI ≤ 2.2 L/min/m), elevated pulmonary capillary wedge pressure (PCWP > 18 mm Hg), or both. A subgroup of 38 patients (19 with abnormal hemodynamics) underwent LVAD ramping. With LVAD ramping, normalization of hemodynamics was achieved in 13 (68%) patients with abnormal hemodynamics. In ramped patients, the CI increased from 2.1 L/min/m (2.0-2.3) to 2.5 L/min/m (2.3-2.6; p = 0.004), and the PCWP dropped from 21 mm Hg (20-26) to 18 mm Hg (14-21, p < 0.001). The 6-minute walk distance improved from 338 m (253-394) to 353 m (320-442, p = 0.041). A 400 rpm change in HMII speed was like a 130 rpm change in HVAD speed and led to a change in cardiac output (CO) of 0.3 L/min. The correlation between device-reported flow and measured CO for both the HMII (Rs = 0.50, p < 0.001) and HVAD (Rs = 0.47, p < 0.001) was moderate. At 3 months after LVAD implant, most patients have normal hemodynamics. Of those patients with abnormal hemodynamics, LVAD ramping results in normalization of hemodynamics and improvement in 6-minute walk distance.