title: Intra-aortic balloon pumping reduces the increased arterial load caused by acute cardiac depression, modifying central and peripheral load determinants in a time- and flow-related way.
abstract: The mechanisms that explain intra-aortic balloon pumping (IABP) effects are not completely understood, and attributing them only to pressure-associated changes in cardiac function would be an oversimplification. Since IABP modifies the aortic and systemic blood-flow pattern, flow-related effects could be expected. To characterize effects of acute heart failure (AHF) on the arterial biomechanics; IABP effects on the arterial biomechanics during AHF, and their potential time-dependence; the association between hemodynamics and biomechanical changes during AHF and IABP. Sheep (n = 6) aortic pressure, flow, and diameter were measured: (1) before (Basal) and (2) 1-3 (HF(1-3)) and 28-30 (HF(28-30)) min after starting halothane to induce AHF; and (3) at specific times (1-3, 14-15 and 28-30 min) during IABP assistance. Calculus: aortic characteristic impedance (Z(c)), beta stiffness (β), incremental (E(INC)) and pressure-strain elastic modulus (E(P)); total arterial compliance (C(G)), total systemic vascular resistance and wave propagation parameters. (1) AHF resulted in an acute increase in aortic and systemic stiffness (HF(28-30) % changes with respect to Basal conditions: β +217%, E (P) +143%, E(INC) +101%, Z(c) +52%, C(G) -13%), associated with the reduction in the aortic blood flow; (2) during AHF IABP resulted in acute beneficial changes aortic and systemic biomechanics (% changes in IABP(1-3) with respect HF(28-30): β -62%, E(P) -68%, E (INC) -66%, Z(c) -38%, C(G) 66%), and in wave propagation parameters, (3) IABP-related changes were time-dependent and associated with changes in aortic blood flow. Aortic and systemic biomechanical and impedance properties are detrimentally modified during AHF, being the changes rapidly reverted during IABP. IABP-related beneficial changes in arterial biomechanics were time-dependent and associated with IABP capability to increase blood flow.
authors: Cardiovascular Haemodynamic Group, Physiology Department, School of Medicine, Centro Universitario de Investigación, Innovación y Diagnóstico Arterial, Republic University, General Flores 2125, 11800 Montevideo, Uruguay. dbia@fmed.edu.uy
authors: Daniel
authors: D
authors: Bia
authors: Edmundo I
authors: EI
authors: Cabrera-Fischer
authors: Yanina
authors: Y
authors: Zócalo
authors: Ricardo L
authors: RL
authors: Armentano
mesh_terms: D000208:Acute Disease; D000818:Animals; D062186:Arterial Pressure / Q000502:physiology*; D001783:Blood Flow Velocity / Q000502:physiology*; D004195:Disease Models, Animal; D006333:Heart Failure / Q000503:physiopathology / Q000628:therapy*; D007423:Intra-Aortic Balloon Pumping; D012756:Sheep; D014655:Vascular Resistance / Q000502:physiology*