Right ventricular dysfunction during intensive pharmacologic unloading persists after mechanical unloading

Right ventricular (RV) dysfunction is associated with adverse outcomes in heart failure (HF). Mechanical unloading should be more effective than pharmacologic therapy to reduce RV afterload and improve RV function. We compared RV size and function after aggressive medical unloading therapy to that achieved in the same patients after 3 months of left ventricular assist device (LVAD) support.

We studied 20 patients who underwent isolated LVAD placement (9 pulsatile and 11 axial flow). Echocardiograms were performed after inpatient optimization with diuretic and inotropic therapy and compared with studies done after 3 months of LVAD support. After medical optimization right atrial pressure was 11 +/- 5 mm Hg, mean pulmonary artery pressure 36 +/- 11 mm Hg, pulmonary capillary wedge pressure 23 +/- 9 mm Hg, and cardiac index 2.0 +/- 0.6 L.min.m(2). Preoperatively, RV dysfunction was moderate (2.6 +/- 0.9 on a 0 to 4 scale), RV diameter at the base was 3.1 +/- 0.6 cm, and mid-RV was 3.5 +/- 0.6 cm. After median LVAD support of 123 days (92 to 170), RV size and global RV dysfunction (2.6 +/- 0.9) failed to improve, despite reduced RV afterload.

RV dysfunction seen on intensive medical therapy persisted after 3 months of LVAD unloading therapy. Selection of candidates for isolated LV support should anticipate persistence of RV dysfunction observed on inotropic therapy.