Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Pulsatile Flow”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 469 records · Page 26Linked to original sources
PubMed1989

Velocity and shear stress distribution downstream of mechanical heart valves in pulsatile flow.

Ten mechanical valves (TAD 27 mm): Starr-Edwards Silastic Ball, Björk-Shiley Standard, Björk-Shiley Concave-Convex, Björk-Shiley Monostrut, Hall-Kaster (Medtronic-Hall), OmniCarbon, Bicer Val, Sorin, Saint-Jude Medical and Hemex (Duromedics) are investigated in a comparative in vitro study. The velocity and turbulent shear stress profiles of the valves were determined by Laser Doppler anemometry in two different downstream axes within a model aortic root. Depending on the individual valve design, velocity peaks up to 1.5 m/s and turbulent shear stress peaks up to 150 N/m2 were measured during the systolic phase. These shear stress peaks mainly occurred in areas of flow separation and intense momentum exchange. Directly downstream of the valves (measuring axis 0.55.dAorta) turbulent shear stress peaks occurred at peak systole and during the deceleration phase, while in the second measuring axis (1.5.dAorta) turbulence levels were lower. Shear stress levels were high at the borders of the fluid jets. The results are discussed from a fluid-dynamic point of view.

Blood Flow Velocity↗
PubMedDate not supplied

[Quantitative evaluation of pulsatile flow in the extremities using a rheographic method].

A model of a limb part represented as a multilayer cylindrical conduction section is considered. The impedance is measured by means of four electrodes, and the exact and approximate expressions for the impedance are derived. With the expressions, one can calculate the value of the pulse blood flow. Various factors affecting the measurement accuracy such as skin conditions, local depths of major vessels, and relative electrode positions are analyzed. Recommendations for the choice of the electrode spacing are given to calculate the pulse and specific blood flow depending upon dimensions of the body part under study, the accuracy being not less than the preset value.

Extremities↗
PubMed1985

[Pulsatility, flow and metabolic diseases].

Metabolic diseases, and particularly diabetes mellitus have a well-established vascular determinism. Diabetic arteriopathy is associated from its onset with elevated tissue blood flow at rest and blood and plasma hyperviscosity. These anomalies are corrected by the perfect equilibration of the glycemia with the artificial pancreas. In 8 to 28% of cases, according to the author, there is an original hemodynamic picture; the enhanced flow hyperpulsatile diabetic arteriopathy observed in a caricatural manner in ulcerated mutilating acropathies. The vasomotor inertia of the diabetic artery and the metabolic neuropathy suggest that surgery to increase blood flow might be of interest in diabetic patients, as a function of results of previous function tests.

Diabetes Mellitus, Type 1↗