Background Pulmonary arterial hypertension (PAH) affects patients with connective tissue diseases (CTD), especially systemic sclerosis (SSc) and MCTD. Despite this, there continues to be delay in screening and diagnosis of these patients.
Objectives We undertook a systematic review to summarize the best evidence for screening and diagnosis of PAH in CTD.
Methods A systematic search was performed in Pubmed, EMBASE, Web of Science and Scopus databases up to June 2012 with an experienced librarian, related to PH and CTD. We only focused on WHO group I PAH and excluded manuscripts that did not rule out interstitial lung disease (WHO group III) or left heart disease (WHO group II), or if the diagnosis of pulmonary arterial hypertension (PAH) was not made by RHC.
Results We started with 2805 titles, 838 abstracts, and included 21 manuscripts. Twelve studies assessed the tricuspid regurgitation velocity (VTR) or equivalent right ventricular systolic pressure (RVSP) using transthoracic echocardiogram (TTE) as a threshold for RHC in patients suspected as having PAH. 11 of these studies were in SSc, and one pertained to SLE. The screening threshold for RHC was VTR >2.73 to >3.16 m/s without symptoms or 2.5 to 3.0 m/s with symptoms and resulted in 20-67% of patients having RHC proven PAH (Table). In the SLE study, VTR >3.0 m/s on TTE led to RHC in 3 patients and none had PAH.
Three studies looked at pulmonary function tests and various DLCO% predicted cut-offs. These studies suggest that a low DLCO% 45-70% is associated with a 5.6-7.4% development of PAH, and the decline in DLCO% is associated with an increase in the specificity (For 60% cut off, spec= 45%, and for 50% cut off, spec=90%]) for PAH. Five studies looked at NT-ProBNP and a cut-off >209pg/ml has a high sensitivity (90-100%) and a specificity ranging from 45-95%.
Single studies looked at EKG findings, cardiac MRI, Chest X-ray, CT, autoantibodies, laboratory values and physical exam findings.
Conclusions Our systematic review shows that most evidence exists for use of TTE, pulmonary function tests, and NT-ProBNP for screening and diagnosis of PAH in CTD. These data will be used to develop guidelines for screening and diagnosis of PAH in CTD.
References Humbert, M., A. Yaici, et al. (2011). “Screening for pulmonary arterial hypertension in patients with systemic sclerosis: clinical characteristics at diagnosis and long-term survival.” Arthritis Rheum 63(11): 3522-3530.
Vachiery, J. L. and G. Coghlan (2009). “Screening for pulmonary arterial hypertension in systemic sclerosis.” Eur Respir Rev 18(113): 162-169.
Disclosure of Interest None Declared