Association of cardiac magnetic resonance-detected myocardial abnormalities with disease characteristics and brain natriuretic peptide levels in systemic sclerosis without cardiac symptoms

Biomarkers in the evaluation of cardiac involvement in systemic sclerosis

Systemic sclerosis is a multisystemic disease for which the heart can be affected leading to cardiac complications and mortality. Up to 80% of patients with systemic sclerosis have cardiac involvement with varying levels of severity. Several molecules have been identified that can be used as markers of cardiac involvement. These biomarkers can arise directly from the heart due to cardiac damage from the disease such as cardiac troponins or from the underlying dysregulated immune process itself such as the proinflammatory cytokines including interleukin (IL)-6. This review aims to summarize the evidence on currently known biomarkers that are can be diagnostic, prognostic or predictive of primary cardiac involvement in systemic sclerosis. We also highlight potential new biomarkers based on the current understanding of the disease process. Clinical use of these markers can benefit patients through earlier identification of those with cardiac involvement, many of whom can be asymptomatic in the early stage, with higher risk of complications, with the overall goal to improve outcomes of these affected patients.

Serum markers in systemic sclerosis with cardiac involvement

Cardiac involvement in systemic sclerosis is a common clinical entity that may range from subclinical to life-threatening complications. The classification of cardiac involvement may be expressed as either primary or secondary involvement. Primary systemic sclerosis heart involvement (SSc-pHI) refers to cardiac pathologies primarily ascribed to systemic sclerosis rather than concomitant conditions like ischemic heart disease and pulmonary hypertension. The timely recognition of cardiac involvement holds significant clinical relevance. Therefore, numerous screening or diagnostic tools have been evaluated to forecast the likelihood of cardiac involvement, particularly in the absence of clinically evident cardiac symptoms. Of these modalities, serum biomarkers are often preferred due to their expeditiousness and non-invasive nature. Hence, the crucial goal of this narrative review is to review serum biomarkers that can be a valuable or promising tool in diagnosing cardiac involvement, especially SSc-pHI, in the early stages or predicting disease prognosis.

Cardiovascular disease risk prediction in scleroderma

OBJECTIVE

Cardiovascular disease risk prediction in scleroderma is important. In this study of scleroderma patients, the aim was to investigate the relationship between cardiac myosin-binding protein-C, sensitive troponin T, and trimethylamine N-oxide and cardiovascular disease risk with the Systematic COronary Risk Evaluation 2 model of the European Society of Cardiology.

METHODS

Systematic COronary Risk Evaluation 2 risk groups of 38 healthy controls and 52 women with scleroderma were evaluated. Cardiac myosin-binding protein-C, sensitive troponin T, and trimethylamine N-oxide levels were analyzed with commercial ELISA kits.

RESULTS

In scleroderma patients, cardiac myosin-binding protein-C and trimethylamine N-oxide levels were higher than healthy controls but sensitive troponin T was not (p<0.001, p<0.001, and p=0.274, respectively). Out of 52 patients, 36 (69.2%) were at low risk, and the other 16 (30.8%) patients were at high-moderate risk with the Systematic COronary Risk Evaluation 2 model. At the optimal cutoff values, trimethylamine N-oxide could discriminate high-moderate risk with sensitivity 76%, specificity 86% and cardiac myosin-binding protein-C with sensitivity 75%, specificity 83%. Patients with high trimethylamine N-oxide levels (≥10.28 ng/mL) could predict high-moderate- Systematic COronary Risk Evaluation 2 risk 15 times higher than those with low trimethylamine N-oxide (<10.28 ng/mL) levels (odds ratio [OR]: 15.00, 95%CI 3.585-62.765, p<0.001). Similarly, high cardiac myosin-binding protein-C (≥8.29 ng/mL) levels could predict significantly higher Systematic COronary Risk Evaluation 2 risk than low cardiac myosin-binding protein-C (<8.29 ng/mL) levels (OR: 11.00, 95%CI 2.786-43.430).

CONCLUSION

Noninvasive cardiovascular disease risk prediction indicators in scleroderma, cardiac myosin-binding protein-C, and trimethylamine N-oxide could be recommended to distinguish between high-moderate risk and low risk with the Systematic COronary Risk Evaluation 2 model.

The Involvement of Smooth Muscle, Striated Muscle, and the Myocardium in Scleroderma: A Review

Systemic sclerosis (SSc) is a complex autoimmune disease characterized by heterogeneous changes involving numerous organs and systems. The currently available data indicate that muscle injury (both smooth and striated muscles) is widespread and leads to significant morbidity, either directly or indirectly. From the consequences of smooth muscle involvement in the tunica media of blood vessels or at the level of the digestive tract, to skeletal myopathy (which may be interpreted strictly in the context of SSc, or as an overlap with idiopathic inflammatory myopathies), muscular injury in scleroderma translates to a number of notable clinical manifestations. Heart involvement in SSc is heterogenous depending on the definition used in the various studies. The majority of SSc patients experience a silent form of cardiac disease. The present review summarizes certain important features of myocardial, as well as smooth and skeletal muscle involvement in SSc. Further research is needed to fully describe and understand the pathogenic pathways and the implications of muscle involvement in scleroderma.

Recent Progress on Micro-Fabricated Alkali Metal Vapor Cells

Alkali vapor cells are the core components of atomic sensing instruments such as atomic gyroscopes, atomic magnetometers, atomic clocks, etc. Emerging integrated atomic sensing devices require high-performance miniaturized alkali vapor cells, especially micro-fabricated vapor cells. In this review, bonding methods for vapor cells of this kind are summarized in detail, including anodic bonding, sacrificial micro-channel bonding, and metal thermocompression bonding. Compared with traditional through-lighting schemes, researchers have developed novel methods for micro-fabricated vapor cells under both single- and double-beam schemes. In addition, emerging packaging methods for alkali metals in micro-fabricated vapor cells can be categorized as physical or chemical approaches. Physical methods include liquid transfer and wax pack filling. Chemical methods include the reaction of barium azide with rubidium chloride, ultraviolet light decomposition (of rubidium azide), and the high-temperature electrolysis of rubidium-rich glass. Finally, the application trend of micro-fabricated alkali vapor cells in the field of micro-scale gyroscopes, micro-scale atomic clocks, and especially micro-scale biomagnetometers is reviewed. Currently, the sensing industry has become a major driving force for the miniaturization of atomic sensing devices, and in the near future, the micro-fabricated alkali vapor cell technology of atomic sensing devices may experience extensive developments.