ABSTRACT.
BACKGROUND : Although cardiac resynchronization therapy (CRT) is
beneficial in most heart failure patients, up to 40% do not respond to
CRT. It has been suggested that multipoint left ventricle pacing (MPP)
would increase the response rate.
AIM : To assess the CRT response rate at 6 months in patients
implanted with a CRT device with the MPP feature activated early after
the implant.
METHODS This was a multicentre, prospective, open-label and
non-randomized study. The primary endpoint was response to biventricular
pacing defined as >15% relative reduction in left
ventricular end-systolic volume (LVESV) comparing echocardiography
measurements performed at baseline and 6 months by a core laboratory.
Among secondary endpoints the combined endpoint of mortality or
all-cause hospitalizations was evaluated. Primary study endpoint and
clinical outcomes were compared to a Quarto II control cohort.
RESULTS: 105 patients were included. The response rate was
64.6% (97.5% lower confidence bound 53%). Mean relative reduction in
LVESV was 25.3% and mean absolute increase in LVEF was 9.4%. The
subjects with device programmed using anatomical approach had showed a
trend toward higher responder rate than those using the electrical
approach (72% vs. 61.1%, p= 0.32). Compared with Quarto II, the
combined endpoint of mortality and or all-cause hospitalizations was
lower in Quarto III (12.4% vs 25.4%, p=0.004).
CONCLUSIONS : Early activation of MPP was not associated to an
advantage increasing echocardiography responders to CRT at 6 months of
follow up. Nevertheless, MPP was associated with better clinical
outcomes in comparison to a historical control cohort. Patients
programmed using widest pacing cathodes had a numerically higher
responder rate.
KEYWORDS .
Heart Failure.
Cardiac Resynchronization Therapy.
Multipoint pacing.
Dyssynchrony.
Outcomes.