Nail Capillary Changes Link to Heart Damage in Scleroderma

A cross-sectional exploratory study published in Advances in Rheumatology reports that structural abnormalities in the peripheral microcirculation, as assessed by nailfold capillaroscopy, are associated with primary heart involvement in patients with systemic sclerosis. The research, conducted at a single center, involved 40 patients who underwent both cardiac magnetic resonance imaging and videocapillaroscopy within four weeks of each other. The findings suggest that the severity of capillary changes in the fingernails may reflect the extent of cardiac injury, potentially offering a non-invasive indicator for monitoring heart complications in this autoimmune disease.

Systemic sclerosis is an immune-mediated rheumatic disease characterized by a triad of vasculopathy, autoimmunity, and fibrosis affecting the skin and visceral organs. Primary heart involvement, or SSc-HI, is a frequent and serious manifestation of the disease, with prevalence estimates ranging from 7% to 44% depending on the diagnostic criteria used. In autopsy studies, the prevalence can reach up to 90%. The condition is often clinically occult, meaning it may not present with obvious symptoms until it manifests as heart failure, arrhythmia, or pericardial involvement, which are associated with a poor prognosis.

The pathogenesis of SSc-HI involves three main mechanisms: vasculopathy, inflammation, and fibrosis. Microvascular involvement leads to endothelial damage and abnormal vasoreactivity, which can result in ischemia-reperfusion cycles in the cardiac microcirculation, akin to a cardiac Raynaud’s phenomenon. Immune-mediated inflammation of the myocardium or pericardium is also described. These microvascular and inflammatory abnormalities can lead to myocardial fibrosis, which is typically characterized by a biventricular, subendocardial, and noncoronary distribution. Histopathological evaluations have revealed a pattern of plaque-like fibrosis with focal myocardial necrosis.

Cardiac magnetic resonance is currently considered the gold standard for assessing cardiac volume and ejection fraction in SSc patients. It offers greater sensitivity than echocardiography for detecting early cardiac changes. Different CMR protocols allow for the assessment of lesions indicative of microvascular, inflammatory, and fibrotic changes. Vasculopathy-related abnormalities are documented by the presence of perfusion defects or changes in quantitative perfusion after pharmacological or cold stress. Myocardial inflammation and fibrosis are demonstrated by the presence of myocardial edema, late gadolinium enhancement, or parametric T1 and T2 mapping images showing diffuse inflammation or fibrosis.

Nailfold capillaroscopy is a non-invasive method used to evaluate structural changes in the peripheral microcirculation. Patients with SSc typically present abnormalities such as capillary dilation, reduced capillary density, avascular areas, microhemorrhages, and disorganization of the nailfold capillary architecture, known as the scleroderma pattern. This pattern is categorized into early, active, and late subtypes based on the degree of capillary dilation and loss. The late scleroderma pattern and more severe capillary abnormalities are associated with more advanced disease and the involvement of certain organs. Previous studies have shown an association between the late pattern and cardiac abnormalities evaluated by electrocardiogram or echocardiography, but the role of capillaroscopy in the context of CMR evaluation was previously unknown.

The study included 40 SSc patients consecutively recruited between December 2021 and January 2024. All participants fulfilled the 2013 American College of Rheumatology/European League Against Rheumatism classification criteria for SSc. Exclusion criteria included smoking, pregnancy, previous cardiovascular disease, pulmonary arterial hypertension, diabetes mellitus, and body mass index greater than 35 kg/m². The mean age of the patients was 51 years, and 95% were female. The majority had diffuse cutaneous SSc, and the mean disease duration was 7.5 years. The most prevalent capillaroscopic pattern was the scleroderma pattern, observed in 82.5% of patients, with 25% of those having a late scleroderma pattern.

The CMR protocol included cine-MRI for measuring biventricular volumes, myocardial mass, and ejection fraction, as well as evaluating pericarditis and pericardial effusion. Perfusion imaging was performed at rest and after cold stress, which consisted of immersing the upper limb in water at 10 degrees Celsius for three minutes. Myocardial perfusion reserve was calculated as the ratio of myocardial blood flow after cold stress to that at rest. Late gadolinium enhancement imaging was performed five minutes after the cold stress perfusion sequence. SSc-HI findings were categorized into vasculopathy-related lesions, indicated by cold-induced perfusion defects and a myocardial perfusion reserve less than 1.0, and fibrosis-related lesions, indicated by late gadolinium enhancement, reduced left ventricular global longitudinal strain, and biventricular failure.

Primary heart involvement on CMR was observed in 55% of the patients. Vasculopathy-related lesions were found in 37.5% of patients, while fibrosis-related lesions were detected in 20%. Among the vasculopathy-related lesions, 5% had cold-induced perfusion defects and 38.2% had a myocardial perfusion reserve less than 1.0. Among the fibrosis-related lesions, 10% had late gadolinium enhancement, 12.5% had a left ventricular global longitudinal strain less than 14%, and 10% had biventricular failure. The quantitative perfusion protocol was adequately performed in 34 patients, and there was no significant difference in myocardial blood flow values at rest and after cold stress. However, 65% of the patients had a delta myocardial blood flow less than 33.8%, indicating an ineffective cardiac vasodilator response.

The group of patients with the late scleroderma pattern on videocapillaroscopy had a significantly higher indexed left ventricular mass and a lower left ventricular global longitudinal strain compared to those with the non-late pattern. The late pattern group also had a significantly higher frequency of moderate or severe pericardial effusion and a higher frequency of fibrosis-related lesions. Specifically, more patients in the late pattern group presented with a left ventricular global longitudinal strain less than 14% and late gadolinium enhancement. These findings suggest that the late scleroderma pattern is associated with more severe cardiac structural and functional abnormalities.

Severe microangiopathy in videocapillaroscopy, depicted by reduced capillary density, was associated with different SSc-HI CMR abnormalities. The mean number of capillary loops per millimeter was lower in patients with late gadolinium enhancement, a left ventricular global longitudinal strain less than 14%, and biventricular failure. There was a trend towards a lower number of capillary loops per millimeter in patients with a myocardial perfusion reserve less than 1.0. The avascular score was significantly higher in patients with a myocardial perfusion reserve less than 1.0, late gadolinium enhancement, and a left ventricular global longitudinal strain less than 14%. A significantly lower number of capillary loops per millimeter and a higher avascular score were observed in patients with fibrosis-related lesions, myocardial involvement, and any SSc-HI compared to those without these abnormalities.

The study found that left ventricular indexed mass was negatively correlated with the mean number of capillary loops per millimeter. This correlation further supports the link between peripheral microvascular changes and cardiac structural alterations. The authors suggest that the peripheral microcirculation may mirror cardiac injuries, indicating a possible shared pathogenic pathway. The presence of more severe videocapillaroscopy abnormalities may support the indication of a CMR to better evaluate SSc-HI in clinical practice. However, the association does not imply causation, and further studies are needed to confirm these findings.

The study has several limitations, including the small sample size, which requires further validation in larger populations. The study population was not enriched with SSc patients with known risk factors associated with SSc-HI, which may have impacted the analysis. Parametric T1 and T2 mapping sequences, which are more sensitive for evaluating diffuse myocardial fibrosis and inflammation, were unavailable. The cross-sectional design did not allow for prospective analyses of videocapillaroscopy risk factors associated with worse CMR findings or clinical outcomes. The authors conclude that SSc-HI CMR abnormalities are frequently observed in SSc patients and are associated with several parameters of severity in capillaroscopy. Further studies with a larger number of patients are needed to confirm the association between SSc-HI characterized by CMR and capillaroscopy abnormalities.

Subject of Research: Association between nailfold capillaroscopy abnormalities and cardiac magnetic resonance findings in systemic sclerosis

Article Title: Primary heart involvement assessed by cardiac magnetic resonance is associated with capillaroscopy abnormalities in systemic sclerosis

Article References: Martins, L., Uellendahl, M., Ferreira, G., & Kayser, C. (2026). Primary heart involvement assessed by cardiac magnetic resonance is associated with capillaroscopy abnormalities in systemic sclerosis. Advances in Rheumatology, 66(1), Article 51. https://doi.org/10.1186/s42358-026-00549-9

Image Credits: AI Generated

DOI: 10.1186/s42358-026-00549-9

Keywords: systemic sclerosis, cardiac magnetic resonance, nailfold capillaroscopy, heart involvement, microcirculation, fibrosis, vasculopathy, rheumatology, autoimmune disease, peripheral microangiopathy, Primary, heart