Echocardiography
Echocardiographic parameters, including
left atrial (LA) dimension, LVEF,
LV end-diastolic volume (LVEDV), and TR grade/TRPG, were measured using
GE Vivid 9 or Philips IE33 acccording to the recommendations from the
american society of echocardiography.
LVEF and LVEDV were quantified by
the M-mode and corrected by the two-dimensional guided biplane Simpson’s
method of disc measurements by echocardiography. Echocardiography
was performed before implantation and at 2-year intervals thereafter in
the absence of clinical events or at the onset of HF.