Recent advances in scleroderma-associated pulmonary hypertension

Pulmonary arterial hypertension in Saudi patients with systemic sclerosis: Clinical and hemodynamic characteristics and mortality

BACKGROUND

Pulmonary arterial hypertension (PAH) is a major cause of morbidity and mortality in patients with systemic sclerosis (SSc). The objective of this study is to describe the clinical characteristics, mortality, and predictors of SSc-PAH in Saudi patients.

METHODS

Retrospective chart review study of SSc patients who were followed for at least 1 year in three tertiary care centers in Saudi Arabia was conducted. Clinical information, echocardiographic findings, and right heart catheterization (RHC) results were collected. Descriptive statistics were used for demographic and disease characteristics.

RESULTS

Fifty-seven patients with SSc were reviewed. PAH was confirmed by RHC in 40 patients (87.5%, females). Their mean age was 45.43 ± 13.48 years. The mean pulmonary artery pressure was 42.9 ± 12.7 mmHg, the pulmonary vascular resistance index was 19.4 ± 7.7 woods unit, and cardiac index was 2.43 ± 0.68 min/m². The median time from symptoms to first assessment was 42.8 ± 115.62 months. Most patients (77.5%) presented with functional Class III or IV and more than half (22.55%) were on dual combination therapy. Ten patients (25%) SSc PAH died over a follow up period of 37 ± 7 months. Compared to SSc patients without PAH, SSc-PAH patients had shorter 6-min walk distance (6MWD) (296.1 ± 116.5 vs. 399.59 ± 40.60 m, P < 0.0001), higher pro-brain natriuretic peptide (1755.8 ± 2123.4 vs. 69.8 ± 44.3 pg/ml P = 0.004), and more frequent Raynaud's phenomenon (RP) (90% vs. 35%, P < 0.0001). Logistic regression showed RP (odds ratio [OR] =48.58, 95% confidence interval [CI]; 3.73-633.10) and 6MWD (OR 1.02: 95% CI; 1.01-1.03) were associated with the development of PAH.

CONCLUSION

Our cohort of Saudi SSc-PAH patients has a younger disease onset and a lower mortality than what is described worldwide despite late presentation and requirement of combination therapy. The presence of RP and lower were associated with the development of SSc-PAH.

Vascular complications in systemic sclerosis: a prospective cohort study

Two major complications in scleroderma patients that cause substantial morbidity and mortality are ischemic digital lesions (DL) and pulmonary hypertension (PH). The clinician's ability to predict which patients will develop these complications is imperfect. We conducted a prospective observational cohort study of 300 patients with scleroderma who were followed for at least a 5-year period. At baseline, patients lacked evidence of PH and were without a current DL. At each 6-month visit, the patient was examined for signs/symptoms of PH and/or a DL. The primary outcomes were (1) PH defined as a mean pulmonary artery pressure ≥ 25 mmHg by right heart catheterization and (2) ≥ 1 DL defined as new onset of severe vascular compromise. Thirty patients (10%) developed PH (11 group 1/PAH, 4 group II, 15 group III) and 69 developed DL. The average time from enrollment until diagnosis of PH was 3.2 ± 2 years. In multivariable analyses, patients who developed PH were more likely to have diffuse disease (HR 3.2, p = 0.004), a forced vital capacity (FVC)/diffusing capacity of the lungs for carbon monoxide (DLCO) ratio > 1.6 (HR 1.7, p = 0.008), and elevated RVSP (HR = 1.07, p = 0.007). Patients who developed PAH were more likely to have a FVC/DLCO ratio > 1.6 (HR = 5.8, p = 0.014), and patients who developed group III PH were less likely to have an elevated FVC (HR = 0.92, p = 0.001). Patients were more likely to develop a DL if they had a history of prior DL (HR = 7.0, p < 0.001), or were men (HR = 2.3, p = 0.007). In a prevalent cohort of scleroderma patients, individuals who develop PH or DL have simple to measure clinical features that can predict these complications years before they occur.

Epidemiology and disease characteristics of systemic sclerosis-related pulmonary arterial hypertension: results from a real-life screening programme

BACKGROUND

Pulmonary arterial hypertension (PAH) is the leading cause of death in systemic sclerosis (SSc). Annual screening with echocardiogram (ECHO) is recommended. We present the methodological aspects of a PAH screening programme in a large Australian SSc cohort, the epidemiology of SSc-PAH in this cohort, and an evaluation of factors influencing physician adherence to PAH screening guidelines.

METHODS

Patient characteristics and results of PAH screening were determined in all patients enrolled in a SSc longitudinal cohort study. Adherence to PAH screening guidelines was assessed by a survey of Australian rheumatologists. Summary statistics, chi-square tests, univariate and multivariable logistic regression were used to determine the associations of risk factors with PAH.

RESULTS

Among 1636 patients with SSc, 194 (11.9%) had PAH proven by right-heart catheter. Of these, 160 were detected by screening. The annual incidence of PAH was 1.4%. Patients with PAH diagnosed on subsequent screens, compared with patients in whom PAH was diagnosed on first screen, were more likely to have diffuse SSc (p = 0.03), be in a better World Health Organisation (WHO) Functional Class at PAH diagnosis (p = 0.01) and have less advanced PAH evidenced by higher mean six-minute walk distance (p = 0.03), lower mean pulmonary arterial pressure (p = 0.009), lower mean pulmonary vascular resistance (p = 0.006) and fewer non-trivial pericardial effusions (p = 0.03). Adherence to annual PAH screening using an ECHO-based algorithm was poor among Australian rheumatologists, with less than half screening their patients with SSc of more than ten years disease duration.

CONCLUSION

PAH is a common complication of SSc. Physician adherence to PAH screening recommendations remains poor. Identifying modifiable barriers to screening may improve adherence and ultimately patient outcomes.

Perioperative management of patients with pulmonary hypertension for non-cardiac surgery

Pulmonary hypertension (PH) is associated with significant morbidity and mortality. While the advent of disease-modifying therapies in the treatment of PH has dramatically increased the life expectancy of these patients, they remain at high risk for perioperative complications. Outcome studies suggest that patients with PH undergoing non-cardiac surgery have higher morbidity and mortality than those without, independent of severity. Despite these risks, more and more of these patients are presenting for non-cardiac surgery. Patients with rheumatologic disorders in particular often have pulmonary arterial hypertension (PAH), a group that is associated with a poorer prognosis. Yet, these patients invariably develop debilitating joint diseases and not uncommonly present for elective surgery. Preoperatively, patients with PH should be appropriately risk stratified based on functional class, etiology, exercise capacity, pulmonary hemodynamics, and the risk of surgery. If the risks and benefits assessment proves favorable, they should undergo optimization prior to surgery, with any chronic therapy continuing without cessation through the perioperative period. A multidisciplinary approach involving all intraoperative physicians is imperative to forming a safe intraoperative plan based on the inherent physiology underlying the patient's disease. Finally, because complications in this patient population often occur postoperatively, patients should be monitored in an appropriate setting with a goal of preventing right ventricular dysfunction. In this review article, we focus on the evaluation, risk stratification, and optimization of patients with PH undergoing non-cardiac surgery.

Expression of Let-7 family microRNAs in skin correlates negatively with severity of pulmonary hypertension in patients with systemic scleroderma

BACKGROUND

Pulmonary hypertension (PH) is a serious complication in patients with systemic scleroderma (SSc), therefore it is important to identify the factors that could predict the presence and progression of PH. Skin biopsy is performed in patients with SSc to examine the type and severity of the disease. MicroRNAs (miRNAs) are potential biomarkers for various cardiovascular diseases including PH.

METHODS AND RESULTS

We determined the skin miRNA expression profile in 15 SSc patients with (n = 6) and without PH (n = 9). A mixture of equal amounts of miRNAs from PH and non-PH patients were prepared and used for miRNA PCR array analysis. The analysis identified 591 upregulated miRNAs and 57 downregulated miRNAs in the PH group. Of these, only miRNAs with a Ct value of less than 35 were subjected to further analysis. When a 1.5-fold difference was considered meaningful, 32 miRNAs were upregulated and 14 miRNAs were downregulated in the PH group. Interestingly, 5 out of 14 downregulated miRNAs belonged to the let-7 family. The results were validated by quantitative real-time PCR with specific primer for each miRNA, which showed significant downregulation of five let-7 family members (let-7a, -7d, -7e, -7f, -7g) in 6 PH compared with 9 non-PH skin samples. The expression levels of let-7d and 7b correlated negatively with pulmonary arterial pressure measured by echocardiography.

CONCLUSIONS

The results suggest that skin miRNA is a potentially useful marker for the presence and severity of PH in patients with SSc.