Utility of echocardiography in assessment of pulmonary hypertension secondary to COPD

Studies have confirmed the close correlation of echocardiographically estim ated pulmonary arterial pressure with invasive measurements in patients wit h chronic obstructive pulmonary disease (COPD), but there are few data on u tility of echocardiographic measurement in assessing pulmonary arterial hyp ertension (PH) in COPD and correlation with pulmonary function tests. Presence or absence of tricuspid regurgitation (TR) was determined by Doppl er echocardiography in 73 consecutive COPD patients attending a hospital ou tpatient clinic. Transtricuspid pressure gradient (TTPG) was calculated. PH was defined as TTPG greater than or equal to 30 mmHg. Patients also underw ent spirometry, forced expiratory volume in one second (FEV1), single breat h gas transfer (carbon monoxide transfer coefficient; (Kco) and carbon mono xide diffusing capacity of the lung; DL,CO) and arterial blood gas measurem ent. Measurable TR was observed in 56/73 patients (77%). There were no differenc es between the group in which TR was observed compared to that in which it was absent, with regard to age, smoking history nor pulmonary function vari ables. PH was seen in 31/56 cases (55%), with good reproducibility. There w ere statistically significant correlations of TTPG with FEV1 (r = -0.26, p = 0.05), Kco (r = -0.31, p = 0.04) and D-L,CO (r = -0.42, p = 0.006) expres sed as % pred. Stepwise regression analysis showed that age and Kco combine d provide a multivariate model for prediction of TTPG. It is concluded the presence and degree of pulmonary arterial hypertension is readily and reliably determined by echocardiography in the majority of c hronic obstructive pulmonary disease patients. Pulmonary arterial hypertens ion is common in severe chronic obstructive pulmonary disease and transtric uspid pressure gradient correlates with spirometry and indices of gas trans fer, similar to previous invasive studies. In view of the adverse effects o f pulmonary arterial hypertension on morbidity and mortality routine echoca rdiography in patients with severe chronic obstructive pulmonary disease ma y be warranted.