Research Article
No Difference in Systolic Dysfunction from Left Ventricular Pressure-Volume Loop’s Area and Stroke Work Between Chronic Late Load vs. Early Systolic LV Load in Porcine Model
Issue:
Volume 10, Issue 4, August 2024
Pages:
46-55
Received:
22 August 2024
Accepted:
9 October 2024
Published:
29 October 2024
Abstract: Background: in increased LV afterload as in hypertension, early systolic LV dysfunction (SD) in late compares to early peak systolic LV load for P-V area, stroke work, potential energy with effective LV work (EW) is not being defined (aortic stenosis, arterial hypertension or coarctation of the aorta) in LVH remodeling. Objectives: to assess in porcine model how LV stroke work, PVA and EW are related to LVH remodeling in developing early SD with HF, between 4th vs 8th week in chronic LL compares to EL. It is suggested that reduced proximal thoracic or asc. aortic compliance results with myocardial ischemia. However, difference for LV O2 demand and effective LV work in different LV afterload is not understood in early development systolic HF. Methods: in fourteen domestic male pigs (28±3 kg) with moderate descending aortic banding having chronic late LV load (LL=8) or ascending aortic stenosis with early systolic LV load (EL=6) SD was assessed, from PVA, in invasive LV pressure-volume loops’ measurements, at 4th vs. 8th week, to assess LV maximal ESPVR, with Millar 5Fr P-V pig-tailed conductance catheter. LV stroke work, and pressure-volume area PVA, reflecting the maximal LV O2 demand were assessed in chronic LL compares to EL from nonlinear regression analysis of maximal LV end-systolic stiffness, in special software. For variance analysis, two-way repeated measures ANOVA was performed, with normality assessment. Results are means±(SEM) or medians for significant p<0.05. Results: LV PVA was not different, in LL compared to EL at 4th vs. 8th week. LV stroke work with effective works were not different and potential energy, neither were changed between 4th vs. 8th week. No difference was found in different LV afterload, in both indexed and absolute LVO2 demand, in LL vs. EL at 4th or 8th week. Indexed PVA parameters with LV stroke work, effective work and potential energy were not different or changed in LL compares to EL between 4th vs. 8th weeks, normalized per body surface-area (in m2). Conclusion: Both absolute and indexed LV stroke work, potential LV energy, PVA with EW and maximum LV O2 demand are not different in LL compares to EL at 4th vs. 8th week of LVH remodeling, indicating no difference in early SD development in increased late vs. early LV afterload.
Abstract: Background: in increased LV afterload as in hypertension, early systolic LV dysfunction (SD) in late compares to early peak systolic LV load for P-V area, stroke work, potential energy with effective LV work (EW) is not being defined (aortic stenosis, arterial hypertension or coarctation of the aorta) in LVH remodeling. Objectives: to assess in por...
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