TY - JOUR
T1 - Effects of changes in airway pressure on the left ventricle and left atrium of dogs
AU - Katzenberg, Charles
AU - Olajos, Marcey
AU - Morkin, Eugene
AU - Goldman, Steven
N1 - Funding Information:
We thank Ms Mary Bryson, Ms Ann Bruning, and Mrs Sharon Boykin for their assistance with preparation of the manuscript and Ms Gwen Roske for her technical assistance. This work was supported by grants from the Veterans Administration, the Gustavus and Louise
PY - 1986/11
Y1 - 1986/11
N2 - Summary: The effects of negative and positive airway pressure were examined in eight closed chest, chronically instrumented dogs to determine beat to beat changes in left ventricular pressure, left ventricular dP/dt, left ventricular dimensions, left atrial dimensions, and oesophageal pressure. As an index of afterload, systolic transmural pressure was calculated by subtracting oesophageal pressure from left ventricular pressure. With each change in airway pressure left ventricular end systolic minor axis diameter and left ventricular end diastolic minor axis diameter increased significantly. Left atrial end diastolic dimension increased significantly with negative airway pressure and did not change with positive airway pressure. Left ventricular dP/dt and left ventricular fractional shortening did not change. With the Mueller manoeuvre left ventricular systolic pressure decreased significantly from 106.0(4.2) mm Hg to 100.9(4.2) mm Hg and systolic transmural pressure increased significantly from 105.1(4.6) mm Hg to 110.4(4.3) mm Hg. With a transient increase in positive airway pressure of 30 mm Hg (4.0 kPa), left ventricular pressure increased significantly from 106.9(4.8) mm Hg to 113.9(5.9) mm Hg and systolic transmural pressure decreased significantly from 106.6(4.9) mm Hg to 99.8(4.6) mm Hg. The addition of positive end expiratory pressure of 10 cm H2O (0.98 kPa) or autonomic blockade with atropine and propranolol did not alter these results. Thus manoeuvres which cause opposite effects on systolic transmural pressure produce similar increases in left heart dimensions, suggesting that increases in pulmonary venous return and not changes in afterload may be the important determinants of left ventricular dimensional changes during changes in airway pressure.
AB - Summary: The effects of negative and positive airway pressure were examined in eight closed chest, chronically instrumented dogs to determine beat to beat changes in left ventricular pressure, left ventricular dP/dt, left ventricular dimensions, left atrial dimensions, and oesophageal pressure. As an index of afterload, systolic transmural pressure was calculated by subtracting oesophageal pressure from left ventricular pressure. With each change in airway pressure left ventricular end systolic minor axis diameter and left ventricular end diastolic minor axis diameter increased significantly. Left atrial end diastolic dimension increased significantly with negative airway pressure and did not change with positive airway pressure. Left ventricular dP/dt and left ventricular fractional shortening did not change. With the Mueller manoeuvre left ventricular systolic pressure decreased significantly from 106.0(4.2) mm Hg to 100.9(4.2) mm Hg and systolic transmural pressure increased significantly from 105.1(4.6) mm Hg to 110.4(4.3) mm Hg. With a transient increase in positive airway pressure of 30 mm Hg (4.0 kPa), left ventricular pressure increased significantly from 106.9(4.8) mm Hg to 113.9(5.9) mm Hg and systolic transmural pressure decreased significantly from 106.6(4.9) mm Hg to 99.8(4.6) mm Hg. The addition of positive end expiratory pressure of 10 cm H2O (0.98 kPa) or autonomic blockade with atropine and propranolol did not alter these results. Thus manoeuvres which cause opposite effects on systolic transmural pressure produce similar increases in left heart dimensions, suggesting that increases in pulmonary venous return and not changes in afterload may be the important determinants of left ventricular dimensional changes during changes in airway pressure.
KW - Afterload
KW - Heart-lung interaction
KW - Venous return
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U2 - 10.1093/cvr/20.11.853
DO - 10.1093/cvr/20.11.853
M3 - Review article
C2 - 3304641
AN - SCOPUS:85047676248
SN - 0008-6363
VL - 20
SP - 853
EP - 862
JO - Cardiovascular research
JF - Cardiovascular research
IS - 11
ER -