Abstract 15275: Impedance Spectrum Analysis After Total Aortic Arch Replacement: Superiority of Decellularized Allografts Compared with Conventional Prostheses
Introduction: To date, no experimental or clinical study provides detailed analysis of changes in vascular impedance after total aortic arch replacement. The present study investigated ventriculoarterial coupling and vascular impedance after replacement of the aortic arch with conventional prostheses vs. decellularized allografts.
Methods: In 10 anesthetized open-chest dogs, total aortic arch replacement was performed with conventional prostheses (n=5) and compared to decellularized allografts (n=5). Left ventricular hemodynamic variables were measured by using a combined pressure-volume-conductance catheter. Aortic flow and pressure were recorded continuously. From the hemodynamic variables end-systolic elastance and effective arterial elastance, the mechanical efficiency (ventriculoarterial coupling) was calculated. Vascular impedance (Z) was assessed by fast Fourier transformation analysis.
Results: While end-systolic elastance (4.10 ± 1.19 vs 4.58 ± 1.39 mmHg/mL, P = .59 / 3.21 ± 0.97 vs 3.96 ± 1.16 mmHg/mL, P = .62) did not differ between the groups and over time, effective arterial elastance showed a higher increase in the conventional prosthesis group in comparison to the decellularized allografts (4.01 ± 0.67 vs 6.18 ± 0.20 mmHg/mL, P = .06 / 5.03 ± 0.35 vs 5.99 ± 1.09 mmHg/mL, P = .34). This led to a worsening of mechanical efficiency in the conventional prosthesis group while ventriculoarterial coupling remained unchanged in the decellularized group (62.5 ± 50.9 % vs 3.9 ± 23.4 %, P = .29). Z showed a significant increase in the conventional prosthesis group whereas it remained unchanged in the decellularized group (32.2 ± 2.2 vs 64.2 ± 3.6, P= 1.2 10-6 / 31.1 ± 1.8 vs 35.3 ± 1.8, P= .13).
Conclusions: In conclusion, total aortic arch replacement leads to contractility-afterload mismatch by means of increased impedance and invert ventriculoarterial coupling ratio after implantation of a conventional prosthesis. Implantation of decellularized allografts preserves vascular impedance and thereby improves ventriculoarterial mechanoenergetics after aortic arch replacement.
- © 2012 by American Heart Association, Inc.