Right ventricular diastolic function and exercise capacity in COPD

• Published in: Respiratory medicine 2015-10, Vol.109 (10), p.1287-1292
• Main Authors: Fenster, Brett E, Holm, Kristen E, Weinberger, Howard D, Moreau, Kerrie L, Meschede, Kimberly, Crapo, James D, Make, Barry J, Bowler, Russell, Wamboldt, Frederick S, Hoth, Karin F
• Format: Article
• Language: English
• Subjects: Aged; Blood Flow Velocity - physiology; Blood pressure; Cancer; Cancer therapies; Cardiology; Cardiovascular disease; Chronic obstructive pulmonary disease; Comorbidity; COPD; Coronary vessels; Diastole - physiology; Diastolic function; Echocardiography, Doppler - methods; Exercise; Exercise Test - methods; Exercise Tolerance; Female; Heart - physiopathology; Heart attacks; Heart rate; Heart Rate - physiology; Humans; Hypertension; Lung diseases; Male; Middle Aged; Predictive Value of Tests; Pulmonary Disease, Chronic Obstructive - diagnostic imaging; Pulmonary Disease, Chronic Obstructive - physiopathology; Pulmonary/Respiratory; Right ventricle; Stroke Volume - physiology; Surgery; Ventricular Function, Left - physiology; Ventricular Function, Right - physiology; Walking - physiology
• ISSN: 0954-6111; 1532-3064
• DOI: 10.1016/j.rmed.2015.09.003

Abstract Background Decreased exercise capacity in chronic obstructive pulmonary disease (COPD) is incompletely explained by pulmonary pathologic and physiologic abnormalities. We evaluated the extent to which right ventricular diastolic function (RVDF) is associated with exercise capacity in COPD. Methods Fifty-one patients with COPD were evaluated by echocardiography, spirometry, and the 6 min walk test (6MWT). RVDF was assessed using 4 echocardiographic parameters: 1) the ratio of tricuspid valve (TV) early (E) and late (A) inflow velocities (TV E/A) 2) TV early tissue Doppler velocity (TV e′) 3) TV deceleration time (DT) and 4) the ratio of TV E and e′ velocities (TV E/e′). Multiple linear regression was used to examine the extent to which these parameters were associated with 6MWT distance. All models adjusted for age, sex, post-bronchodilator FEV1 /FVC, resting heart rate, and use of supplemental O2 during 6MWT. A regression model was calculated for each of the 4 markers of RVDF. Results Forty-seven percent of the sample had GOLD stage III or IV COPD. All 51 subjects had preserved left ventricular ejection fraction (LVEF, mean = 71.7%, SD = 7.8%). A higher TV E/A ratio was associated with increased 6MWT distance (p = 0.001). TV e′, TV DT and TV E/e′ did not have a statistically significant association with 6MWT distance in regression models. Conclusions In a cohort with moderate to severe COPD and normal LVEF, TV E/A was associated with 6MWT distance after adjusting for relevant demographic and medical covariates. RV diastolic dysfunction may independently contribute to exercise intolerance in COPD.