Few Changes in Heart Health in SSc Patients Seen Over Time on MRIs
Routine scans for scleroderma heart disease of 'minimal value' in most cases
Monitoring the progression of subclinical heart disease with MRI scans suggested that abnormalities remain largely stable over time in people with systemic sclerosis (SSc), and such routine imaging may be of “minimal value” to most patients, a small study reported.
The study, “Subclinical Systemic Sclerosis Primary Heart Involvement by Cardiovascular Magnetic Resonance Shows No Significant Interval Change,” was published in ACR Open Rheumatology.
Scleroderma occurs when the immune system wrongly turns against the tissue that lies under the skin and other organs, causing them to scar and thicken.
In some cases, scar tissue builds in the heart. While MRI can help detect subclinical heart disease, meaning an initial period of disease when no symptoms are manifest, how MRI findings change over time is unclear.
Study into way of monitoring heart disease in scleroderma patients
To know more, a team of researchers in the U.K. watched for changes on MRI scans of patients’ hearts taken at two points in time.
Their study included 31 adults (23 women, eight men) with a diagnosis of SSc; 21 had the limited disease subtype and 10 had diffuse SSc. Their median age was 52, and their disease duration was a median of nine years.
About half (51.6%) had a history of interstitial lung disease (ILD), which occurs when lung tissue becomes inflamed and scarred, and eight (25.8%) had some cardiovascular risk factor.
A median interval of 33 months (2 years and 9 months) separated the two MRI scans, and at least one year had passed since the first MRI scan in all cases. Three years was the interval for more than two-thirds of these patients (67.7%).
At the time of their first MRI scan, more than half (58.1%) were taking disease-modifying antirheumatic drugs (DMARDs, such as mycophenolate mofetil and hydroxychloroquine). They continued receiving this type of scleroderma treatment at least up until the second MRI scan, with two patients starting on DMARD treatment during the follow-up period.
Most patients (87.1%) also were receiving treatment with a vasodilator, which widens blood vessels to help the blood flow easier.
The first MRI scan revealed focal late gadolinium enhancement in four people. This means that they had areas of scarred heart tissue.
One of these four patients showed an increase in the amount of heart scar tissue on the second MRI scan, along with a more than two-times increase in the modified Rodnan skin score, from six to 13 points. The Rodnan skin score is a measure of skin thickness that serves as a surrogate of disease severity in scleroderma.
Two other patients had new focal late gadolinium enhancement. One had new heart symptoms and a diagnosis of myositis (an inflammation of the muscles) and arthritis (an inflammation of the joints).
These three patients had the diffuse subtype of SSc and ILD. Two tested positive for anti-Scl-70 antibodies, which have been associated with diffuse scleroderma.
No other changes between the two MRI scans were observed, suggesting that “abnormalities remain largely stable” over time, the researchers noted.
Findings in SSc-ILD patients and those using DMARDs
From the first to the second MRI scan, there was a mild decrease in stroke volume per the body’s surface area, a measure of how much blood is pumped out of the heart’s left ventricle. But “the means remained within normal limits, with little clinical relevance,” the researchers wrote.
Compared with patients with ILD, those without ILD had a greater decrease in end-systolic and end-diastolic stroke volume per the body’s surface area. End-systolic volume refers to the volume of blood that’s left in the ventricle after it’s pumped out, and end-diastolic volume refers to the volume of blood that gets into the ventricle after it’s filled again.
They also had a greater increase of the median myocardial perfusion reserve (MPR), a measure of the maximal volume of blood that can go through the heart’s muscle above baseline conditions.
Over time, a reduction in lung function was linked to a reduction of not only MPR but also to the left ventricle’s ejection fraction, which refers to how much blood is actually pumped out of the left ventricle as it contracts.
An increase in the blood level of N-terminal pro-brain natriuretic peptide (NT-proBNP) was also linked to a reduction of MPR. Usually only a small level of NT-proBNP reaches the bloodstream, and a high level can mean that the heart isn’t pumping as much blood as the body needs.
Patients on DMARD treatment had higher end-systolic and end-diastolic stroke volume per body surface area on their first MRI scan than those who were not on DMARDs.
From the first to the second MRI scan, they also had an increase in mean native T1, a measure that’s been associated with disease changes in heart muscle disease and diffuse fibrosis.
There were no other “clinically meaningful changes” for patients receiving DMARDs or vasodilators.
“These data suggest that routine interval monitoring with [heart MRI] is of minimal value,” the researchers concluded, adding however that patients “in a poor prognostic group may benefit from follow-up with [heart MRI] as well as cardiac biomarker measurement.”
Larger studies are needed “to advance more tailored use of [imaging] in patients with SSc,” they noted.
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