I am Dr. Julio Núñez, I'm a cardiologist,
Coordinator of Heart Failure Unit
of Hospital Clínico Universitario from València, Spain.
I'm also a full professor of the Department of Medicine
of University of València.
In this study we sought to evaluate the effect
on maximum functional capacity-
capacity measured by peak VO2
of beta blockers,
withdrawal in patient with heart failure and preserved
ejection fraction and documented established chronotropic
incompetence.
That is, a blunted high rise heart rate response
to exercise.
This was an independent crossover randomised clinical trial
performed in two centres in Spain.
The primary end point was short term change in peak VO2
and percent predicted peak VO2.
Secondary end points included,
changing quality of life, biomarkers and
left ventricular diastolic parameters.
First, we found that beta blocker discontinuation led to a
significant short term increase in maximal functional
capacity evaluated as an absolute change in peak VO2 and
also percent predicted peak VO2.
Interestingly, the magnitude
of the change found here in this study,
about a 12% increase
in percent predicted peak VO2, where in most of the patients
in most of cases in most of cases,
clinically meaningful.
Along this line,
we also found a significant improvement in quality of life
and left ventricular diastolic parameters.
First, this study confirms that chronotropic incompetence
blunted heart rate response to exercise maybe,
maybe playing a crucial role in the pathophysiology of
effort intolerance in some,
in, in some of,
of HFpEF patients no, that's probably, we should be,
we should be more proactive by defining this phenotype in
patients with HFpEF.
Second, beta blockers are drugs that
are widely used in patient with HFpEF,
despite the solid evidence endorse,
endorsing its utility uh
drugs that have a negative chronotropic response,
probably maybe play in maybe exasperating chronotropic
incompetence in this subset of specific patients.
Obviously the
the results of these findings stopping beta blockers in this
subgroup of patients probably should
should translate into short term benefits in this,
in this specific subset.
Of course,
this is a small clinical trial performed into centres
performed in a short term frame.
Obviously we need to confirm these studies in,
these findings in,
in larger studies and probably in an extended follow-up,
but in our, in my opinion,
this open,
exciting new research line,
targeting higher rate,
not lowering,
but increasing heart rate as a potential therapeutic target
in patients with HFpEF.
A syndrome that currently we don't,
we do not know exactly how to treat it.