One of the challenges facing us today is applying a new paradigm to the
management of our patients with cardiovascular disease. With our
diagnostic capabilities we can personalise our investigation of a
patient and subsequently personalise the treatment of that patient.
By not only looking at the patient's history and their ECGs but actually by looking at the
substrate at what's going on inside the heart we can have a some idea of which
patients are likely to respond and which might not. We can use data that's been
derived from magnetic resonance imaging or even CT scanning imaging now
and this can give us an idea of the patient's anatomy by using computer
modelling we can test whether a patient will respond to therapy so we're moving
much more towards the sort of precision or targeted approach in individual
patients try to improve response. Guy's and St Thomas' is one of the
largest teaching hospitals, university hospitals, in the United Kingdom based in
the centre of London there has in fact been a St Thomas' Hospital based on
the Southbank of the Thames since the 12th century. The clinical and
intellectual atmosphere here is unique together with my colleagues in
bioengineering and advanced cardiovascular imaging including MR
physics we have the ability to answer very quickly questions which we ask.
All under one roof. We're seeking to expand the boundaries of how diagnostic imaging
can inform therapeutic intervention in patients with heart rhythm disturbances
to understand why a particular patient on a particular day suffers a rhythm
disturbance which could potentially be fatal.
In the United Kingdom at least 1.5
to 2 percent of our population suffers with atrial fibrillation therefore it's
very important for us to find better ways to manage this condition in a more
cost-effective way. The current interventions we use
seek to ablate or destroy in a controlled way clearly defined cardiac
tissue advanced cardiac imaging allows us to assess atrial structure.
It's important for us to understand which parts of the atrium are the sites that
we should target and also how safely can we target them.
Sitting here within the XMR environment we have the ability to take a patient on
the morning of their procedure perform a scan to assess their atrial structure and
function and then to tailor our procedure according to that individual
patient's anatomy and depending on where we see sites with scar or abnormal tissue
or sites with thick or thin atrial tissue.
Cardiac resynchronisation therapy is an
extremely powerful treatment. But approximately a third of patients don't
respond to this treatment. By looking for areas of scar, by looking for areas of
late electrical or mechanical activation and by using that data and taking it
into the catheter lab to actually guide the procedure at the time we hope to be
able to then make a bespoke treatment for the patient to guide the lead to
the optimal position in that patient's heart to improve the response to therapy.
We were also able to develop in conjunction with the, our biomedical
engineers here. Biophysical models derived from MRI and electrical input we
can actually test in silico what the response to a patient's treatment
will be before we actually give it to the patient. There are several studies and
programmes we're undertaking in conjunction with other centres in the UK and Europe
actually to validate these models and also we want to make the models more
sophisticated and require less invasive data. We want them to be quicker as well
so we hope to be able to now create this in hours to minutes in the future.
When we are looking at patients with ventricular tachycardia, cardiac MR
allows us to image the shape and size of the ventricle in its function but
particularly it allows us to image the scar and the areas around the scar, the
border zone, or the grey zone, but getting that information into the cardiac
catheterisation laboratory is difficult. That is why we're pursuing doing these
procedures inside the MR scanner where we can both observe the substrate
accurately but also accurately to target it by tracking our device to do the
ablation, the catheter into the right part of the substrate. We can ablate arrhythmias
in patients inside an MR scanner for atrial flutter
but doing this for ventricular tachycardia is much harder. We have developed the
technologies working with Siemens Healthcare and Imricor to be able to do this
in an animal model and a next step over the coming year or two for us is to
translate that into studies in patients.
Almost every patient we see is
interested in understanding better why they have suffered the problem they have
suffered. Therefore every patient who comes into hospital contact with a
doctor or a nurse is offered the opportunity, if appropriate, to
participate in a research study. The UK's National Health Service indicates that
all patients should have access to clinical research should they wish to be
involved in research. We do screening of patients as they attend their clinics
and patients are identified if they have specific pathological conditions or
clinical disease states and if these conditions match up to current research
studies they are approached for inclusion into these research studies.
The transition of clinical data acquisition will ultimately be dependent
on the publication and dissemination of our research findings but we are already
starting to see that patients are benefitting from some of the work that's
being conducted on our site. With the support of the infrastructure provided
by the NHS, King's College London and our in-house services in bioengineering
medical physics, cardiovascular imaging and interventional cardiac electrophysiology
we hope that our work using imaging technology to assess arrhythmia
substrate in patients will lead to earlier identification of patients for whom
intervention is appropriate and better interventions in those patients.