Follow-up and outcomes
Patients were followed through regular outpatient visits at the
institution after hospital discharge. Echocardiogram was performed after
6 months of the procedure. Hospitalization for heart failure was
assessed at follow-up. Super responders were considered patients with
LVEF > 50% at 6-month. Those patients who did not return
within 1 year after CRT implantation were contacted by telephone. The
primary outcome was to assess short-term mortality between upgrade and
De novo-CRT implantation. Survival was assessed as the time from CRT
implantation to all-cause mortality.