PURPOSE: The diagnosis of pulmonary hypertension (PH) in patients with scleroderma related interstitial lung disease (SILD) is important for patient management. Doppler echocardiography (DE) is commonly used to screen for PH. The utility of DE to detect PH in patients with SILD is described.
METHODS: Potential participants in a Phase IV clinical trial evaluating inhaled medications in patients with PH/SILD were reviewed. SILD was determined by HRCT of the chest. DE measurement of the PASP by tricuspid jet velocity, spirometry, DLCO, 6MW and right heart catheterization (RHC) were required for evaluation. PH defined as a PASP of > 40 mmHg by DE was compared to RHC (mean PAP (mPAP) > 25 mmHg at rest). Results were expressed as mean ± SD. Comparative analyses were performed using Mann-Whitney Testing.
RESULTS: 13 patients met criteria for review. 8 had PH and 5 had no PH defined by RHC. FVC%(57±14 vs 49±10), DLCO%(33±11 vs 22±7) & 6MW(332M±109 vs 295M±75) were similar between groups. The PH group showed a trend towards increased desaturation during exercise(8.9%±5 vs 3.4%±4, p=0.06). Mean PAP(34mmHg±11 vs 21±3, p=0.003) and PVR(4.9WU±3 vs 2.5±0.7, p=0.03) were greater in the PH group. Of the 8 who had PH defined by RHC, 5 also had PH by DE. 3/5 patients without PH by RHC were PH positive by DE. The sensitivity, specificity, PPV and NPV for DE was 62.5%, 40%, 62.5%, and 40%. PASP estimates by DE in the PH group overestimated RHC PASP in 2 cases (38%), underestimated PASP in 3 (25%) cases and were correct in 3 (25%) cases. In the no PH group, DE overestimated PASP in 3 of 5 (60%) while 2/5 (40%) were correct.
CONCLUSION: Doppler echocardiography has a poor discriminative ability to predict the presence of PH in patients with SILD and can overestimate PASP in up to 60% of patients without PH.
CLINICAL IMPLICATIONS: Right heart catheterization should be performed in patients with SILD when PH is suspected and initiation of lifelong medical therapy is considered.
DISCLOSURE: Kevin Chan, Grant monies (from industry related sources) Actelion; No Product/Research Disclosure Information