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Cardiac magnetic resonance’s potential for predicting potentially fatal cardiovascular
disease
The use of magnetic resonance imaging (MRI) to determine
heart function has been slow to catch on, but a study from
Duke Health researchers shows that stress cardiac MRI
not only diagnoses disease, but can also predict which cases
are potentially fatal. Results from a large, multi-centre
study suggest that cardiac magnetic resonance, or CMR,
has potential as a non-invasive, non-toxic alternative to
stress echocardiograms, catheterisations and stress nuclear
examinations in identifying the severity of coronary artery
disease.
‘We’ve known for some time that CMR is effective at
diagnosing coronary artery disease, but it’s still not commonly
used and represents less than 1% of stress tests used in this
country,’ said senior author Dr Robert Judd, co-director of
the Duke Cardiovascular Magnetic Resonance Centre.
‘One of the impediments to broader use has been a
lack of data on its predictive value – something competing
technologies have,’ Judd said. ‘Our study provides some
clarity, although direct comparisons between CMR and
other technologies would be definitive.’
Judd and colleagues analysed data from more than 9
000 patients who underwent CMR at seven US hospitals,
encompassing up to 10 years of follow up. For patients
without any history of heart disease and at low risk, based
on traditional clinical criteria, those with an abnormal CMR
scan were 3.4 times more likely to die compared to patients
with a normal CMR scan. For the entire patient population,
the researchers found a strong association between an
abnormal stress CMR and mortality, even after adjusting for
patient age, gender and cardiac risk factors.
‘Non-invasive cardiac stress testing is a cornerstone in the
clinical management of patients with known or suspected
coronary artery disease,’ Judd said, noting that CMR works
as well as or better than other examinations at identifying
heart wall motion, cell death and the presence of low blood
flow. In addition, the technology does not require any
radiation exposure, which is essential in nuclear stress tests
that are by far the most commonly used in the USA.
‘There are a number of reasons for the limited use of stress
CMR, including availability of good-quality laboratories,
exclusion of patients who cannot undergo magnetisation,
and a lack of data on patient outcomes,’ Judd said. ‘With
the findings from this study suggesting that stress CMR is
effective in predicting mortality, we provide a strong basis
for a head-to-head study between stress CMR and other
modalities.’
Source: Medical Brief 2019