Key result
Impaired DLCO tracks chronic heart failure severity and correlates moderately with lower peak oxygen uptake.
Why the study?
How do alveolar gas diffusion and the alveolar-capillary unit behave in relationship to chronic heart failure severity?
Cross-Sectional (n=191)
How do alveolar gas diffusion and the alveolar-capillary unit behave in relationship to chronic heart failure severity?
Answers are grounded in this paper and cite their sources.
In chronic heart failure, alveolar gas diffusion progressively worsens with disease severity due to reduced lung tissue participating in gas exchange, though the remaining alveolar-capillary units become more efficient in severe disease.
AIMS: Alveolar gas diffusion (DLCO) is impaired in chronic heart failure (CHF). Diffusion depends on membrane diffusion (DM) and the amount of blood participating in gas exchange (VC). How DM, VC, and the alveolar-capillary unit behave in relationship to CHF severity is unknown. METHODS AND RESULTS: We measured pulmonary function, including DLCO, DM, VC, and alveolar volume (VA), in 191 CHF patients in NYHA class I-III. CHF patients were grouped accordingly to peak exercise oxygen uptake (pVO(2)): group <12 mL/min/kg (n=24), group 12-16 (n=76), group 16-20 (n=64), and group >20 (n=27). DLCO, DM, VC, and VA were lowest in severe CHF and were linearly related to pVO(2) (DLCO, r=0.577, P<0.001; DM, r=0.490, P<0.001; VC, r=0.216, P<0.01; VA, r=0.565, P<0.01). DM/VC ratio, an index of the alveolar-capillary unit efficiency, was higher in group <12 (0.49+/-0.39 mL/min/mmHg/mL) and >20 (0.46+/-0.29), compared with 12-16 (0.34+/-0.19) and 16-20 (0.35+/-0.17). CONCLUSION: DLCO progressively worsens as CHF severity increases due to reduction in lung tissue participating to gas exchange (low VC and VA). In severe CHF, the few working alveolar-capillary units are the most efficient as shown by the high DM/VC. This is useful for maintaining gas exchange efficiency in severe CHF.
No takes yet. Share an insight, caveat, or question.
Agostoni et al. (2006) conducted a cross-sectional in Chronic heart failure (n=191). Peak exercise oxygen uptake (pVO2) vs. Higher pVO2 groups was evaluated on Alveolar gas diffusion (DLCO) correlation with pVO2 (r=0.577, p=<0.001). Alveolar gas diffusion (DLCO) progressively worsens with increasing chronic heart failure severity and is linearly related to peak exercise oxygen uptake (r=0.577, P<0.001).
Synapse has enriched 10 related papers. Consider them for comparative context: