Atrial natriuretic peptide predicts disease progression and digital ulcers development in systemic sclerosis 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.

Natriuretic Peptides: It Is Time for Guided Therapeutic Strategies Based on Their Molecular Mechanisms

Natriuretic peptides (NPs) are the principal expression products of the endocrine function of the heart. They exert several beneficial effects, mostly mediated through guanylate cyclase-A coupled receptors, including natriuresis, diuresis, vasorelaxation, blood volume and blood pressure reduction, and regulation of electrolyte homeostasis. As a result of their biological functions, NPs counterbalance neurohormonal dysregulation in heart failure and other cardiovascular diseases. NPs have been also validated as diagnostic and prognostic biomarkers in cardiovascular diseases such as atrial fibrillation, coronary artery disease, and valvular heart disease, as well as in the presence of left ventricular hypertrophy and severe cardiac remodeling. Serial measurements of their levels may be used to contribute to more accurate risk stratification by identifying patients who are more likely to experience death from cardiovascular causes, heart failure, and cardiac hospitalizations and to guide tailored pharmacological and non-pharmacological strategies with the aim to improve clinical outcomes. On these premises, multiple therapeutic strategies based on the biological properties of NPs have been attempted to develop new targeted cardiovascular therapies. Apart from the introduction of the class of angiotensin receptor/neprilysin inhibitors to the current management of heart failure, novel promising molecules including M-atrial natriuretic peptide (a novel atrial NP-based compound) have been tested for the treatment of human hypertension with promising results. Moreover, different therapeutic strategies based on the molecular mechanisms involved in NP regulation and function are under development for the management of heart failure, hypertension, and other cardiovascular conditions.

Endocrine functions of the heart: from bench to bedside

Heart has a recognized endocrine function as it produces several biologically active substances with hormonal properties. Among these hormones, the natriuretic peptide (NP) system has been extensively characterized and represents a prominent expression of the endocrine function of the heart. Over the years, knowledge about the mechanisms governing their synthesis, secretion, processing, and receptors interaction of NPs has been intensively investigated. Their main physiological endocrine and paracrine effects on cardiovascular and renal systems are mostly mediated through guanylate cyclase-A coupled receptors. The potential role of NPs in the pathophysiology of heart failure and particularly their counterbalancing action opposing the overactivation of renin-angiotensin-aldosterone and sympathetic nervous systems has been described. In addition, NPs are used today as key biomarkers in cardiovascular diseases with both diagnostic and prognostic significance. On these premises, multiple therapeutic strategies based on the biological properties of NPs have been attempted to develop new cardiovascular therapies. Apart from the introduction of the class of angiotensin receptor/neprilysin inhibitors in the current management of heart failure, novel promising molecules, including M-atrial natriuretic peptide (a novel atrial NP-based compound), have been tested for the treatment of human hypertension. The development of new drugs is currently underway, and we are probably only at the dawn of novel NPs-based therapeutic strategies. The present article also provides an updated overview of the regulation of NPs synthesis and secretion by microRNAs and epigenetics as well as interactions of cardiac hormones with other endocrine systems.

Responses to exercise in systemic sclerosis-associated interstitial lung disease

INTRODUCTION

Pulmonary complications in systemic sclerosis (SSc) significantly increase morbidity and mortality. Our aim was to determine the factors limiting exercise capacity in SSc patients with and without interstitial lung disease (ILD), and to identify and quantify abnormalities during exercise that might assist in clinical assessment of this complication.

METHODS

Fifteen patients with SSc and ILD (SSc-ILD) were compared with 10 patients with SSc without ILD and 9 age- and sex-matched normal volunteers. Subjects performed symptom-limited incremental treadmill exercise with online measurement of respiratory gas exchange, arterial blood gas sampling and measurement of neurohormones in venous blood.

RESULTS

Patients with SSc-ILD had lower exercise capacity than SSc patients without ILD or normal subjects (peak oxygen consumption (PV̇O₂ ) (17.1 [4.2] vs. 22.0 [4.7] and 23.0 [5.4] ml kg^-1  min^-1 , respectively, mean [SD], p < 0.01 ANOVA), but PV̇O₂ did not correlate with static pulmonary function measurements. Ventilatory equivalent for CO₂ (V̇E/V̇CO₂ ; nadir) was higher in SSc-ILD patients than the other two groups (36.6 [8.0] vs. 29.9 [4.4] and 30.0 [2.5], p < 0.005) as were peak exercise dead-space tidal volume ratio (0.44 [0.06] vs. 0.26 [0.09] and 0.26 [0.05], p < 0.001) and peak exercise alveolar-arterial difference (28.9 [16.9] vs. 18.8 [14.0] and 11.5 [6.9] mmHg, p < 0.05). Atrial natriuretic peptide was elevated in both SSc patient groups.

CONCLUSIONS

SSc-ILD results in lower exercise capacity than SSc without ILD, and abnormalities of gas exchange are seen. The possible use of cardiopulmonary exercise testing to identify disease and quantify impairment in SSc-ILD merits further study.

The prognostic role of the echocardiographic tricuspid annular plane systolic excursion/systolic pulmonary arterial pressure (TAPSE/sPAP) ratio and its relationship with NT-proANP plasma level in systemic sclerosis

Background

The tricuspid annular plane systolic excursion/systolic pulmonary arterial pressure (TAPSE/sPAP) ratio is an echocardiographic estimation of the right ventricle to pulmonary artery (RV/PA) coupling, with a validated prognostic role in different clinical settings. Systemic sclerosis (SSc) patients without evident cardiovascular involvement frequently display subtle RV impairment. The amino-terminal atrial natriuretic peptide (NT-proANP) plasma level relates to SSc disease progression and mortality. We aimed to assess the prognostic value of the TAPSE/sPAP ratio and its relationship with NT-proANP plasma level in SSc patients without overt cardiovascular involvement.

Methods

We retrospectively analysed 70 SSc consecutive patients, with no clinical evidence of cardiovascular involvement or pulmonary hypertension (PH), and 30 healthy controls (HC) in a retrospective, single-centre study. All SSc patients underwent recurrent clinical and echocardiographic assessments and NT-proANP plasma level was assessed at baseline. SSc-related cardiovascular events and deaths were extracted during a 6-year follow-up. The complete work-up for the diagnosis, treatment and management of PH performed along the 6 years of follow-up referred to the 2015 European Society of Cardiology guidelines.

Results

Systemic sclerosis patients showed lower TAPSE/sPAP ratio at baseline compared to HC [SSc median value = 0.71 mm/mmHg, (IQR 0.62-0.88) vs. HC median value = 1.00 mm/mmHg, (IQR 0.96-1.05); p < 0.001]. Multivariable Cox analysis revealed TAPSE/sPAP ratio as an independent predictor for SSc-related cardiovascular events [HR = 3.436 (95% CI 1.577-7.448); p = 0.002] and mortality [HR = 3.653 (95% CI 1.712-8.892); p = 0.014]. The value of TAPSE/sPAP ratio < 0.7 mm/mmHg was identified as an optimal cut-off for predicting adverse outcomes (p < 0.001) by receiver operating characteristic (ROC) analyses. NT-proANP level significantly related to TAPSE/sPAP ratio (r = 0.52, p < 0.001). TAPSE/sPAP ratio combined with NT-proANP showed an overall significant prognostic role in this SSc population, confirmed by Kaplan-Meier analysis (Log rank p < 0.001).

Conclusion

The TAPSE/sPAP ratio, as an index of RV/PA coupling, is an affordable predictor of cardiovascular events and mortality in SSc and, combined with NT-proANP level, may improve the clinical phenotyping and prognostic stratification of SSc patients.

Circulating NT-proANP level is a predictor of mortality for systemic sclerosis: a retrospective study of an Italian cohort

Objectives: The authors aimed to evaluate the role of N-terminal proANP (NT-proANP) and of NT-proBNP circulating levels as predictive markers of death due to systemic sclerosis (SSc).Methods: The authors retrospectively enrolled 51 SSc patients. At baseline, NT-proBNP and NT-proANP circulating levels and clinical features were collected. Date and causes of death were extracted during a 6-year follow-up.Results: 13 SSc patients (23.2%) died for SSc complications (9 for interstitial lung disease and 4 for pulmonary arterial hypertension). The median NT-proBNP plasma level did not significantly differ (p > 0.05) in SSc patients died or alive [645 (448-1026) fmol/ml vs 592 (409-789) fmol/ml]. The median NT-proANP plasma level was significantly (p < 0.01) higher in SSc died than in SSc patients alive [4000 (2100-6722) fmol/ml vs 1640 (1381-2721) fmol/ml]. The Kaplan-Meier analysis revealed that SSc patients with increased NT-proANP level had increased mortality (p < 0.05). In the multivariate analysis, DLco [HR 0.966 (0.934-0.999), p < 0.05] and NT-proANP level [HR 1 (1-1), p < 0.05] were predictive markers of death due to SSc.Conclusions: NT-proANP plasma level is a predictive marker of death due to SSc.