Serial Measurements of Tricuspid Regurgitation Pressure Gradient by Echocardiography Predict Prognosis In Idiopathic Pulmonary Fibrosis

Abstract

Background and Objectives: Idiopathic Pulmonary Fibrosis (IPF), especially with emphysema, reportedly involved with Pulmonary Hypertension (PH). However, it is not elucidated whether pulmonary arterial pressure changes serially during the course and influence on prognosis in IPF. We examined whether serial measurements of Tricuspid Regurgitation Pressure Gradient (TRPG) by echocardiography were meaningful predictors of IPF patient survival. Methods: We retrospectively investigated 83 IPF patients. The echocardiographic TRPG cutoff was set at 30 mmHg, and the subjects were divided into two groups: high TRPG and normal TRPG. We also evaluated the relationship between serial TRPG changes during follow-up. Results: A total of 28 patients were included in the high TRPG group. The high TRPG group showed significantly lower %FVC and %DLco, higher A-aDO 2 , shorter 6-minute walk test distance, and more frequent emphysema than the normal TRPG group. The high TRPG group also had poorer survival than the normal TRPG group. A multivariate Cox proportional hazard model demonstrated that TRPG, %FVC, and A-aDO 2 significantly affected patient survival. Thirty-six patients underwent echocardiography twice. At the time of the second echocardiog- raphy, 7 patients with normal TRPG at baseline (n=22) increased to a TRPG of more than 30 mmHg. These patients had significantly showed poorer survival. Conclusions: TRPG is an independent prognostic factor in IPF. Emphysema involvement, de- creased DLco, and decreased FVC were associated with an increase in TRPG. Serial measure- ments of TRPG are recommended for the early detection of PH and predict prognosis in IPF patients.