PowerPoint Presentation
L. Wu, MD; C.P. Allaart, MD, PhD; G.J. de Roest, MD; M.L.
Hendriks, MA; A.C. van Rossum, MD, PhD; C.C. de Cock MD, PhD
ACC Scientific Sessions, San Francisco, CA9 March 2013
The influence of right ventricular pacing on response to
biventricular stimulation -An acute pressure-volume loop study-VUmc
Basispresentatie1I would like to thank the organizing committee for
the invitation to present my research. I will talk about the
influence of RV pacing on the response to Biv pacing.Cardiac
resynchronization therapyStandard therapy in end-stage heart
failureLV only versus biventricular pacing
Leclercq et al. JACC 2002Thibault et al., Circ 2011Kass et al.,
Circ 1999
p=0.001Hemo staafVUmc Basispresentatie2Cardiac resynchronization
therapyContribution RV only pacing?Detrimental effects on LVIn LBBB
patientsHigher degree of mechanical dyssynchrony Decrease in
contractility
Thambo et al., Circ 2004Sweeney et al., JACC 2006Auricchio et
al., JACC 2002Tops et al., JACC 2009
But the contribution of RV stimulation remains controversial. RV
pacing is associated with detrimental effects on the LV. It is
known that in patients with a conventional pacemaker, RVA pacing
causes remodeling of the LV, asymmetrical hypertrophy of the
septum, impaired cardiac output and LVEF. In patients with reduced
EF, RV pacing gives a larger electrical delay. And in the presence
of a conduction delay, this delay is even larger. In LBBB patients,
RV pacing causes an even higher degree of mechanical dyssynchrony
and a decrease in contractility. CRT has a high non-response rate,
maybe this high non-response rate is partially caused by the
effects of RV pacing. A theory for CRT response is that fusion of
the activation wave fronts can cause a better hemodynamic response
(dP/dtmax). Fusion means that there is an activation wave front
from the patients intrinsic RBB and the LV paced wave front. We
expect that patients with a normal AV-delay will need LV only
pacing to achieve fusion. While patients with a long AV-delay needs
biventricular pacing, as you can see here. We believe we should
focus on the role of RV pacing, to see what the effect of RV pacing
is in CRT patients.AimTo investigate the influence of RV pacing on
hemodynamic response during biventricular stimulation
Therefore the aim of our study is to investigate the influence
of RV pacing on hemodynamic response during biventricular pacing.
MethodsPatients eligible for CRTTemporary pacing leadsConductance
measurements
RA leadRV leadPL lead
Conductance catheterTemporary pacing leads were placed at the PL
site, in the RV and in the RA. A conductance catheter was
introduced into the LV cavity to measure pressure and volumes
throughout the whole cardiac cycle, during intrinsic rhythm and
during the different pacemodalities, as you can see in this movie.
Here you see the PV loop during Biv pacing and now you see the PV
loop without pacing.Pressure-volume loop
BaselineRV onlyLV onlyBiventricular
Here you see an example of one patient. Here you see the PV-loop
on the X-axis you see the volume and on the Y-axis you see the
pressure. The first one is a baseline loop, then a loop during RVA
pacing, PL and PLRVA pacing. The grey surface of the PV-loop is the
stroke work. What you can see is that the SW changes during the
different pacing modes. Also the form of the PL-loop changes. In
this case you see that the SW of PLRVA pacing is larger than during
RVA and PL pacing.
Haage en JongewaardResultsBaseline characteristicsn=59Age
(yrs)6710Male39 (66%)QRS (ms)15421Ischaemic, n36 (61%)NYHA, nI / II
/ III / IV0 / 14 / 45 / 0NT-pro BNP (ng/L)16371375LVEDV
(ml)294151LVESV (ml)232142LVEF (%)2213In total, 59 patients were
included with a mean age of 67, mostly male, prolonged QRS complex
and decreased LVEF
Acute effect of pacing on SW p=NSp