severe refractory asthma. Ann Allergy Asthma Immunol 2013;111: 402–407. 5 Wechsler ME, Laviolette M, Rubin AS, Fiterman J, Lapa e Silva JR, Shah PL, Fiss E, Olivenstein R, Thomson NC, Niven RM, et al. Asthma Intervention Research 2 Trial Study Group. Bronchial thermoplasty: long term safety and effectiveness in severe persistent asthma. JACI 2013;132:1295–1302. 6 Chakir J, Haj-Salem I, Gras D, Joubert P, Beaudoin EL, Biardel S, Lampron N, Martel S, Chanez P, Boulet LP, et al. Effects of bronchial thermoplasty on airway smooth muscle and collagen deposition in asthma. Ann Am Thorac Soc 2015;12:1612–1618. 7 Denner DR, Doeing DC, Hogarth DK, Dugan K, Naureckas ET, White SR. Airway inflammation after bronchial thermoplasty for severe asthma. Ann Am Thorac Soc 2015;12:1302–1309. 8 Pretolani M, Dombret M-C, Thabut G, Knap D, Hamidi F, Debray MP, Taille C, Chanez P, Aubier M. Reduction of airway smooth muscle mass by bronchial thermoplasty in patients with severe asthma. Am J Respir Crit Care Med 2014; 190:1452–1454. 9 Miller MR, Hankinson J, Brusasco V, Burgos F, Casaburi R, Coates A, Crapo R, Enright P, van der Grinten CP, Gustafsson P, et al.; ATS/ ERS Task Force. Standardisation of spirometry. Eur Respir J 2005; 26:319–338. 10 LeBlanc A, Robichaud P, Lacasse Y, Boulet LP. Quantification of asthma control: validation of the Asthma Control Scoring System. Allergy 2007;62:120–125. Copyright © 2016 by the American Thoracic Society The Real Face of Borderline Pulmonary Hypertension in Connective Tissue Disease To the Editor: Pulmonary arterial hypertension (PAH), defined as a mean pulmonary artery pressure (mPAP) greater than 25 mm Hg in the absence of an elevated left atrial pressure, is the leading cause of death in patients with systemic scleroderma (SSc) (1–3). Patients with SSc and a borderline elevation in mPAP (21–24 mm Hg) are prone to develop manifest PAH (4, 5). However, the functional or structural vascular abnormality that explains the elevated pulmonary pressure in these patients is obscure. Here we describe the case of a patient with SSc-PAH in whom profound pulmonary vascular remodeling was demonstrated before the development of increased pulmonary artery pressure. A 71-year-old woman experienced shortness of breath and, over the course of several years, a progressive decline in exercise tolerance. After the development of a Raynaud’s phenomenon, sclerodactyly, and a positive anticentromere antibody test, diagnosis was made of limited cutaneous systemic sclerosis (lcSSc). Other than hypothyroidism and systemic hypertension, she had no relevant medical history. Her lung diffusion capacity for carbon monoxide (DL CO ) was 31%, whereas high-resolution computed tomography (HRCT) showed no signs of interstitial lung disease. Because of the discrepancy between the observed severe decrease in DL CO and imaging findings, it was decided to obtain a lung biopsy via video-assisted thoracoscopic surgery. Surprisingly, histological findings consisted of extensive pulmonary vascular abnormalities. The pulmonary arteries were dilated and showed signs of media-hypertrophy and eccentric intimal-fibrosis, suggestive of pulmonary hypertension (Figures 1A and 1B). There were no signs of capillary congestion, interstitial fibrosis or plexiformic lesions. Pulmonary veins showed no arterialization but some intimal fibrosis (Figure 1C). In addition, there was focal thickening of the interlobular septa with lymphangiectasia. A diffuse mild increase of alveolar macrophages was observed, mostly siderophages. Interestingly, small parenchymal vessels showed widespread nonoccluding loose intima fibrosis. In some small vessels, a subendothelial neo-media with a neo-lamina elastic was observed. The neo-media was separated from the preexisting media by a thick layer of collagen-rich intima-fibrosis (Figures 1D–1F). These latter findings are characteristic for SSc-PAH (6). At right heart catheterization, a mPAP of 22 mm Hg was measured. At that moment, the patient was referred to our center for further evaluation. The pulmonary function test showed no abnormalities other than a decreased DL CO , whereas the cardiopulmonary exercise testing revealed a low O 2 -pulse, decreased ventilator efficiency, and a modest decrease in oxygen saturation measured by pulse oximetry near the end of exercise. A right heart catheterization was repeated, this time with an exercise protocol for study purposes. Baseline measurements: mean pulmonary arterial wedge pressure (mPAP): 22 mm Hg, mean right atrial pressure (mRAP): 3 mm Hg, pulmonary arterial wedge pressure (PAWP): 6 mm Hg, pulmonary vascular resistance (PVR): 203 dynes$s/cm 5 , cardiac output (CO): 6.3 l/m, arterial oxygen saturation (Sa O 2 ): 96%, mixed venous oxygen saturation (Sv O 2 ): 74%. Remarkably, although no increased pressures were seen at rest, the mPAP increased during exercise to 44 mm Hg, and the DmPAP/DCO slope was 6.9 mm Hg/L/min. Furthermore, PVR increased to 909 dynes$s/cm 5 , CO increased to 9.5 L/m, and Sv O 2 decreased to 51%. Sildenafil was started and the patient was re-evaluated annually after the start of treatment. Despite an initial improvement in symptoms, the patient presented 4 years later with worsening of her shortness of breath and exercise intolerance. Right heart catheterization demonstrated elevated pulmonary pressures and increased pulmonary vascular resistance at rest (mPAP: 44 mm Hg, mRAP: 12 mm Hg, PAWP: 8 mm Hg, PVR: 702 dynes$s/cm 5 , CO 4.1 L/min, Sv O 2 : 67%). An endothelin-receptor antagonist was started, and the patient is currently stable. Here we describe extensive pulmonary vascular abnormalities in a patient with SSc without PH, according to the hemodynamic criteria of the clinical pulmonary hypertension guidelines (3). Because early PAH-specific treatment may improve survival in patients with SSc-PAH, it is of utmost importance to recognize these patients early (7). Our case, together with the observation that the PVR is increased in many patients with SSc with a borderline increase in mPAP, raises the question whether pulmonary pressures are sensitive enough to detect pulmonary vascular abnormalities in patients with SSc (8, 9) We speculate that extensive pulmonary vascular disease can be present in patients with patients, although hemodynamics are within normal ranges. Future studies are needed to establish whether this is a general future in SSc. 1428 AnnalsATS Volume 13 Number 8 | August 2016 LETTERS