Abstract P254: Hypertension: A proposed Mechanistic Pathway for Arterial System Remodeling

Abstract

Arterial properties change during hypertension (HTN) development. The time course of the changes can be used as a marker of vascular remodeling in the development of HTN. Study Aim: To determine whether pressure induced changes in vascular properties result in alterations in pressure-flow patterns that impact the load for ventricular function: input & characteristic impedance, A rterial C ompliance (AC)= SV/PP (stroke volume)/(pulse pressure), AC=Tau/peripheral resistance (PR), and PP were investigated. Methods: Pressure and flow relations were investigated in dogs during the development of renal-HTN over 4-weeks (Wks). The sensitivity of hemodynamic markers of vascular remodeling was evaluated by changes in AC= SV/PP, and by AC= Tau/PR and PP. Results: All BP components increased during the development of HTN. Changes in Input Impedance, increased through Wks 2 to 4. Increases in the steady component of the cardiac cycle were reflected by peripheral PR, and changes in the pulsatile component were reflected by changes in AC=SV/PP, and AC=Tau /RP; and changes in characteristic impedance. PP and PAP increased by Week 2, reflection of the cardiac and arterial workloads and vascular Tension RP that progressed through Wk 4 Conclusion: Reliable and accessible markers that indicate changes in arterial pressure, flow & volume, are: PP and AC (SV/PP), and AC (Tau /TPR). These variables detected increases in the heart-load and alterations in pressure-flow patterns that impair cardiovascular-function resulting in HTN-CVD; input and characteristic impedance, also provides remodeling information about the arterial system but are not readily available to clinicians.