Schrijen F, Ehrlich W, Permutt S
Pflugers Arch. 1975 Mar 26;355(3):205-15. doi: 10.1007/BF00583684.
Cardiovascular functions were evaluated beat by beat during 29 spontaneous deep breaths in three conscious dogs. When pleural pressure was significantly lower than during quiet breathing, stroke volume was reduced, heart rate elevated, as well as transmural pressure in the pulmonary artery (PPA-Ppl) and in the thoracic aorta (PAO-Ppl); the left ventricular filling pressure (LVEDP-Ppl) did not decrease. The authors suggest that these findings are not consistent with the classical hypothesis which explains the decrease in left ventricular output primarily by a reduction in the venous return to the left heart. The results indicate that the decrease in pleural pressure is responsible for an increase in the afterload on the left heart and suggest that this is the predominate factor in the reduction of the stroke volume without decrease in left ventricular filling pressure.
在三只清醒犬进行29次自主深呼吸期间，逐搏评估心血管功能。当胸膜压力显著低于安静呼吸时，每搏输出量减少，心率升高，肺动脉跨壁压（PPA - Ppl）和胸主动脉跨壁压（PAO - Ppl）也升高；左心室充盈压（LVEDP - Ppl）并未降低。作者认为，这些发现与经典假说不一致，该假说主要通过左心静脉回流减少来解释左心室输出量的降低。结果表明，胸膜压力降低导致左心后负荷增加，这表明这是在左心室充盈压未降低的情况下每搏输出量减少的主要因素。
