Comparing the PAH patients according to their DLCO: results from a Greek PH center.

<bold>Introduction:</bold> Now days, more data indicate diffusion capacity for carbon monoxide (DLCO)’s contribution to survival prediction of patients with pulmonary hypertension. <bold>Objective:</bold> To describe clinical, hemodynamic and echocardiographic characteristics of PAH patients according to their DLCO. <bold>Results:</bold> 67 Pulmonary Arterial Hypertension (PAH) patients have been followed and treated in our center. 41.8% have been diagnosed as IPAH, 55.2% as PAH due to connective tissue disease (CDT) mostly systemic sclerosis (75.6%), 3% due to portal hypertension and HIV. They were divided into 2 groups according to their DLCO (Group1 = DLCO≥45% predicted, Group2 = DLCO<45%), revealing the following results. Group1:89.5% female, median age 60yrs (49-69);68.4% in WHO-FC II,31.6% in WHO-FCIII. 31.6% have IPAH, 63.1% PAH due to CTD. Group2:52.5% female, median age 69yrs (59-76);30.4% in WHO-FC II, 60.9% in WHO-FCIII, 8.7% in WHO-FCIV. 39.1% have IPAH, 60.9% PAH due to CTD. The main hemodynamic and echocardiographic differences are: <table-wrap><object-id>erj;64/suppl_68/PA2502/TB1</object-id><object-id>T1</object-id><object-id>TB1</object-id><table><colgroup><col></col><col></col><col></col><col></col></colgroup><tbody><tr><td></td><td><bold>Group1</bold></td><td><bold>Group2</bold></td><td><bold>p</bold></td></tr><tr><td>Mean PAP mmHg</td><td>26 (21-38)</td><td>34 (28-48)</td><td>0.034</td></tr><tr><td>CI L/min/m²</td><td>2.54 (2.22-3.47)</td><td>2.24 (1.93-2.5)</td><td>0.019</td></tr><tr><td>PVR WU</td><td>3 (2.5-5.1)</td><td>6.33 (3.96-8.3)</td><td>0.005</td></tr><tr><td>FEV1pred %</td><td>90 (74.2-105.8)</td><td>81.6 (59.3-92.0)</td><td>0.073</td></tr><tr><td>FVCpred %</td><td>99 (79.3-103.6)</td><td>92 (60.6-100.0)</td><td>0.189</td></tr><tr><td>6MWT m</td><td>421 (411-500.25)</td><td>285 (247.5-349)</td><td>0.001</td></tr><tr><td>TAPSE mm</td><td>22 (20.5-24)</td><td>18 (16.5-20)</td><td>0.003</td></tr><tr><td>RVSP mmHg</td><td>43 (37.5-53.5)</td><td>60 (48-75)</td><td>0.016</td></tr><tr><td>TAPSE/RVSP</td><td>0.51 (0.31-0.61)</td><td>0.35 (0.19-0.40)</td><td>0.005</td></tr><tr><td>TRVmax (m/sec)</td><td>3.0 (2.92-3.55)</td><td>3.6 (3.1-4.1)</td><td>0.028</td></tr><tr><td>PA diameter mm</td><td>23 (20-29)</td><td>29 (25-30)</td><td>0.014</td></tr></tbody></table></table-wrap> <bold>Conclusion:</bold> In our Center PAH patients with DLCO<45% predicted are mainly men, have worse functional status, more severe PH and have parameters and indices that carry worse prognosis.