ISSN:
1540-8191
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
The chronic changes of the end-systolic pressure-volume relationship (ESPVR) after regional myocardial infarction were evaluated in a sheep model. Pressure-volume area (PVA) obtained from the pressure-volume diagram and left ventricular oxygen consumption (LVO2) were studied. The regional myocardial infarction was created by ligating distal branches of the left coronary artery. ESPVR was obtained using a conductance catheter during transient inferior vena cava occlusion. Measurements were performed at baseline (n = 13), 1 hour (n = 8), 3 months (n = 9), and 6 months (n = 4) after infarction. Ees, the slope of the ESPVR did not change at 1 hour after infarction and remained the same at 3-month and 6-month measurements (baseline 2.26 ± 1.24 mmHg/mL, 1 hour 2.71 ± 1.06, 3 months 3.46 ± 1.51, 6 months 2.45 ± 0.64, NS). Because of the ventricular dilatation, which was demonstrated as an increase in changes of end-systolic volume (Ves) correlating with the time course after infarction (y = -3.21 + 0.128±, r = 0.454, p 〈 0.05), V0, the volume intercept of the ESPVR increased at 1 hour after the infarction, and showed a tendency to increase at 3 months and 6 months after the infarction (baseline -18.0 ± 22.5 mL; 1 hour -0.9 ± 11.6; 3 months 5.4 ± 10.9, 6 months 9.2 ± 23.1, baseline vs 3 months p 〈 0.05, baseline vs 6 months p 〈 0.05). PVA and LVO2 were unchanged over time after infarction (PVA: baseline 2097 ± 1526 mmHg/mL per 100 g-1; 1 hour 1771 ± 699; 3 months 2483 ± 1086; 6 months 1,608 ±1,010, NS), (LVO2: baseline 40.6 ± 13.1 ± 10–3 mL/100 g-1 per beat-1; 1 hour 42.9 ± 9.7; 3 months 35.0 ± 8.6; 6 months 31.2 ± 18.1, NS). Chronic regional infarction in the sheep model did not affect Ees over 6 months, but significantly increased V0 after the increase in the acute phase. PVA and LVO2 were not affected by this regional infarction either acutely or over 6 months.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1540-8191.1995.tb00656.x
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