P131 CT emphysema score, dynamic hyperinflation and ventilatory efficiency during exercise in patients with COPD
D. Elia, N. Sverzellati, P. Tzani, M. Aiello, V. Vecchio, E. Marangio, A. Chetta
2011
Thorax
Pulmonary hyperinflation has the potential for significant adverse effects on cardiovascular function in COPD. The aim of this study was to investigate the relationship between dynamic hyperinflation and cardiovascular response to maximal exercise in COPD patients. Methods We studied 48 patients (16F; age 68 yrs 68; BMI 2664) with COPD. All patients performed spirometry, plethysmography, Lung diffusion capacity for carbon monoxide (TLco) measurement, and symptom-limited cardiopulmonary exercise
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... test (CPET). The end-expiratory lung volume (EELV) was evaluated during the CPET. Cardiovascular response was assessed by change during exercise in oxygen pulse (DO 2 Pulse) and double product, that is, the product of systolic blood pressure and heart rate (DP reserve), and by the oxygen uptake efficiency slope (OUES), that is, the relation between oxygen uptake and ventilation. Results Patients with a peak exercise EELV (%TLC) $75% had a significantly lower resting FEV 1 /VC, FEF 50 /FIF 50 ratio and IC/TLC ratio, when compared to patients with a peak exercise EELV (%TLC) <75%. Dynamic hyperinflation was strictly associated to a poor cardiovascular response to exercise: EELV (%TLC) showed a negative correlation with DO 2 Pulse (r ¼À0.476, p¼0.001), OUES (r ¼À0.452, p¼0.001) and DP reserve (r ¼À0.425, p¼0.004). Furthermore, according to the ROC curve method, the EELV (% TLC) cut-off point which maximised sensitivity and specificity, with respect to a DP reserve value <10 000 as threshold value, was $75 % (0.76 sensitivity and 0.80 specificity). Conclusion The present study shows that COPD patients with dynamic hyperinflation have a poor cardiovascular response to exercise. This finding supports the view that in COPD patients, dynamic hyperinflation may affect exercise performance not only by affecting ventilation, but also cardiac function. Background Volumetric CT scan is used for evaluating the severity of emphysema in COPD patients. The aim of this study was to ascertain whether volumetric CT scan of emphysema may provide information on dynamic hyperinflation and ventilatory efficiency during exercise in COPD patients. Methods We studied 20 patients (5 F; age 67 yrs 69; BMI 26 kg/m 2 64) with COPD. All patients performed baseline lung function test,
doi:10.1136/thoraxjnl-2011-201054c.131
fatcat:xhahpgb6eng4rmcx5r5yfoe6a4