Agostoni Piergiuseppe, Bussotti Maurizio, Cattadori Gaia, Margutti Eliana, Contini Mauro, Muratori Manuela, Marenzi Giancarlo, Fiorentini Cesare
Centro Cardiologico Monzino, IRCCS, Istituto di Cardiologia, Università di Milano, via Parea 4, 20138 Milan, Italy.
Eur Heart J. 2006 Nov;27(21):2538-43. doi: 10.1093/eurheartj/ehl302. Epub 2006 Oct 6.
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.
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).
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.
慢性心力衰竭（CHF）患者存在肺泡气体扩散（DLCO）受损的情况。气体扩散取决于膜扩散（DM）和参与气体交换的血量（VC）。目前尚不清楚DM、VC以及肺泡 - 毛细血管单位在CHF严重程度方面的表现。
我们对191例纽约心脏协会（NYHA）心功能I - III级的CHF患者进行了肺功能测量，包括DLCO、DM、VC和肺泡容积（VA）。CHF患者根据峰值运动摄氧量（pVO₂）进行分组：<12 mL/min/kg组（n = 24）、12 - 16组（n = 76）、16 - 20组（n = 64）和>20组（n = 27）。严重CHF患者的DLCO、DM、VC和VA最低，且与pVO₂呈线性相关（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）。与12 - 16组（0.34 ± 0.19）和16 - 20组（0.35 ± 0.17）相比，<12组（0.49 ± 0.39 mL/min/mmHg/mL）和>20组（0.46 ± 0.29）的DM/VC比值（肺泡 - 毛细血管单位效率指标）更高。
由于参与气体交换的肺组织减少（低VC和VA），随着CHF严重程度增加，DLCO逐渐恶化。在严重CHF中，少数仍在工作的肺泡 - 毛细血管单位效率最高，如高DM/VC所示。这有助于维持严重CHF时的气体交换效率。
