Abstract 330: Relationship Between On-Treatment Decreases in Inappropriate Versus Absolute or Indexed Left Ventricular Mass and Increases in Ejection Fraction in Hypertension
Although in cross-sectional studies left ventricular mass (LVM) which exceeds that predicted by work load (inappropriate LVM [LVMinappr]), but not absolute LVM or LVM index, is inversely related to LV ejection fraction (EF), whether LVMinappr (%observed/predicted LVM) accounts for decreases in EF is unclear. In 168 mild-to-moderate hypertensives treated for 4 months, using echocardiography, we assessed whether on-treatment decreases in absolute LVM, LVM index (LVMI) or LVMinappr are associated with on-treatment changes in EF. Although in patients with an LVMI>51g/m2.7 (n=112)(change in LVMI=-13.7±1.2g/m2.7, p<0.0001), but not in patients with an LVMI≤51g/m2.7(n=56)(change in LVMI=1.3±1.7g/m2.7) LVMI decreased with treatment; treatment failed to increase EF in either group (1.2±1.0% and 2.7±1.4% respectively). In contrast, in patients with inappropriate LV hypertrophy (LVH) (LVMinappr>150%, n=33) LVMinappr decreased (-32±4%, p<0.0001) and EF increased (5.0±1.8%, p<0.0001) after treatment, whilst in patients with a LVMinappr≤150% (n=135), neither LVMinappr (-0.5±2%), nor EF (0.9±0.9%) changed with therapy. With adjustments for LV wall stress and other confounders, whilst on-treatment decreases in LVM or LVMI were weakly related to an attenuated EF (partial r=0.17, p<0.05), on-treatment decreases in LVMinappr were strongly related to increases in EF (partial r=-0.38, p<0.0001)(p<0.0001, comparison of partial r values) even after further adjustments for LVM or LVMI. In conclusion, decreases in LVMinappr but not LVM or LVMI are strongly related to on-treatment increases in EF. LVH can therefore be viewed as a compensatory change that preserves EF, but when in excess of that predicted by stroke work, as a pathophysiological process accounting for a reduced EF.
- © 2012 by American Heart Association, Inc.