Early Detection of PAH in Systemic Sclerosis Achieved Using Ultrasound Technology
In a recent study published in the journal Arthritis Research & Therapy, a team of researchers from Germany uncovered new insights into PAH detection in Scleroderma patients, determining that PH-screening using echocardiography in systemic sclerosis patients should be performed at rest and during exercise.
Pulmonary hypertension (PH) is a common complication in systemic sclerosis (SSc) which can occur at any stage of the disease and has been observed in 15-27 % of patients. In most cases, PH is due to pulmonary arterial hypertension (PAH) which is associated with SSc (SSc-APAH).
At the moment, there are ten PAH-targeted drugs available for these patients, making an early diagnosis of PH/APAH essential in SSc-patients. Echocardiography at rest is the most important non-invasive method for the detection of PH and has been recommended for screening of patients at risk in several guidelines.
Previous studies showed that patients with systemic sclerosis and increased pulmonary arterial pressure response to exercise were impaired in their physical exercise capacity. As a result, assessing exercise hemodynamics obtained trough right heart catheterization (RHC) and by non-invasive stress Doppler-echocardiography (SDE) may help to identify abnormal pulmonary circulation and patients with PH/SSc-APAH at an early stage. However, the role of SDE for PH-screening is unclear due to the lack of prospective confirmatory data.
In order to analyze if SDE improves sensitivity and specificity of detecting PH in comparison to echocardiography at rest, in their study titled “Stress-Doppler-Echocardiography for early detection of systemic sclerosis associated pulmonary arterial hypertension,” Ekkehard Grünig from the Centre for Pulmonary Hypertension Thoraxclinic in Heidelberg, Germany along with colleagues conducted a confirmation of diagnosis, RHC at rest and during exercise in 76 SSc patients.
Results revealed that 29% of the patients had PH confirmed by RHC, with 4 due to concomitant left heart diseases, 3 with lung diseases and 15 patients with SSc-APAH. Echocardiography at rest missed PH-diagnosis in 5 of 22 PH patients. The sensitivity of echocardiography at rest was 72.7%, and the specificity was 88.2% at rest. Stress-Doppler-echocardiography missed PH-diagnosis in 1 of the 22 PH-patients during low-dose exercise and improved sensitivity to 95.2%, but reduced specificity to 84.9%, partly due to concomitant left heart disease.
Based on these results, the researchers concluded that using RHC as the gold standard in all patients showed that SDE markedly improved sensitivity in detecting manifest PH to 95.2% compared to 72.7% using echocardiography at rest only.