In-Vitro Evaluation of Hot-Film Anemometry Using a Sensor-Tipped Coronary Guide-wire

During coronary catheterization, the epicardial coronary arteries are visually assessed for stenoses on the coronary angiogram. However, the functional significance of disease in the coronary arterial tree, the increased resistance to blood flow, may easily be over- or underestimated by using a 2D projection.

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A Novel Carotid Covered Stent Design: In Vitro Evaluation of Performance and Influence on the Blood Flow Regime at the Carotid Artery Bifurcation

Annals of Biomedical Engineering ◽

10.1007/s10439-013-0863-x ◽

2013 ◽

Vol 41 (9) ◽

pp. 1990-2002 ◽

Cited By ~ 16

Author(s):

Foad Kabinejadian ◽

Fangsen Cui ◽

Zhe Zhang ◽

Pei Ho ◽

Hwa Liang Leo

Keyword(s):

Blood Flow ◽

Carotid Artery ◽

Flow Regime ◽

Covered Stent ◽

Stent Design ◽

In Vitro Evaluation ◽

Carotid Artery Bifurcation ◽

Evaluation Of Performance

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Effect of passive myocardium on the compliance of porcine coronary arteries

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00090.2003 ◽

2003 ◽

Vol 285 (2) ◽

pp. H653-H660 ◽

Cited By ~ 31

Author(s):

Leila H. Hamza ◽

Quang Dang ◽

Xiao Lu ◽

Ayesha Mian ◽

Sabee Molloi ◽

...

Keyword(s):

Coronary Arteries ◽

Cross Sectional Area ◽

Sectional Area ◽

Arterial Tree ◽

Cross Sectional ◽

Video Densitometry ◽

Relationship Of ◽

Intravascular Pressure

The objective of this study was to determine the effect of passive myocardium on the coronary arteries under distension and compression. To simulate distension and compression, we placed a diastolic-arrested heart in a Lucite box, where both the intravascular pressure and external (box) pressure were varied independently and expressed as a pressure difference (ΔP = intravascular pressure – box pressure). The ΔP-cross-sectional area relationship of the first several generations of porcine coronary arteries and the ΔP-volume relationship of the coronary arterial tree (vessels >0.5 mm in diameter) were determined using a video densitometric technique in the range of +150 to –150 mmHg. The vasodilated left anterior descending (LAD) coronary artery of six KCl-arrested hearts were perfused with iodine and 3% Cab-O-Sil. The intravascular pressure was varied in a triangular pattern, whereas the absolute cross-sectional area of each vessel and the total arterial volume were calculated using video densitometry under different box pressures (0, 50, 100, and 150 mmHg). In the range of positive ΔP, we found that the compliance of the proximal LAD artery in situ (4.85 ± 3.8 × 10–3 mm2/mmHg) is smaller than that of the same artery in vitro (16.5 ± 6 × 10–3 mm2/mmHg; P = 0.009). Hence, the myocardium restricts the compliance of the epicardial artery under distension. In the negative ΔP range, the LAD artery does not collapse, whereas the same vessel readily collapses when tested in vitro. Hence, we conclude that myocardial tethering prevents collapse of large blood vessel under compression.

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Intravascular ultrasound imaging of the coronary arteries: an in vitro evaluation of measurement of area of the lumen and atheroma characterisation

Heart ◽

10.1136/hrt.68.9.276 ◽

1992 ◽

Vol 68 (9) ◽

pp. 276-281 ◽

Cited By ~ 14

Author(s):

M. H Anderson ◽

I. A Simpson ◽

D. Katritsis ◽

M. J Davies ◽

D. E Ward

Keyword(s):

Intravascular Ultrasound ◽

Ultrasound Imaging ◽

Coronary Arteries ◽

In Vitro Evaluation ◽

Intravascular Ultrasound Imaging

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Guide-wire entrapment by inferior vena caval filters: in vitro evaluation.

Radiology ◽

10.1148/radiology.198.1.8539409 ◽

1996 ◽

Vol 198 (1) ◽

pp. 71-76 ◽

Cited By ~ 61

Author(s):

J A Kaufman ◽

J W Thomas ◽

S C Geller ◽

S M Rivitz ◽

A C Waltman

Keyword(s):

Inferior Vena ◽

Guide Wire ◽

Inferior Vena Caval ◽

In Vitro Evaluation

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Augmentation of sickling process due to turbulent blood flow

Journal of Applied Physiology ◽

10.1152/jappl.1976.40.1.60 ◽

1976 ◽

Vol 40 (1) ◽

pp. 60-66 ◽

Cited By ~ 5

Author(s):

P. D. Stein ◽

H. N. Sabbah ◽

A. K. Mandal

Keyword(s):

Blood Flow ◽

Turbulent Flow ◽

Sickle Cell ◽

Sol Gel ◽

Control Sample ◽

Mechanical Stresses ◽

Hydrodynamic Stresses ◽

Sickle Cell Crises ◽

Hot Film

The purpose of this study was to determine if the fluid mechanical stresses associated with turbulent blood flow can contribute to the sickling process. Blood from seven patients with sickle cell disease was subjected to intermediate and high levels of turbulent flow in vitro. Turbulence was quantitated by hot film anemometry. Control samples showed 20 +/- 3% sickled cells. Cells subjected to intermediate levels of turbulent flow showed 26 +/- 4% sickling (P less than 0.01); and blood subjected to high intensities of turbulence showed 31 +/- 4% sickling (P less than 0.01). A quantitative count by electronmicroscopy, performed in one patient, showed polymerization of the hemoglobin indicative of sickling in more cells subjected to turbulence than in the control sample. A turbulence-reducing agent, polyethylene oxide, diminished the augmentation of the sickling process as it reduced turbulence at comparable Reynolds numbers. These results support the hypothesis that a deleterious effect upon hemoglobin SS erythrocytes may occur due to the mechanical stresses of turbulent flow. The agitation associated with turbulent flow presumably modifies the stabilizing factors of the intracellular colloidal solution of hemoglobin, thereby contributing to sol-gel transformation. Such hydrodynamic stresses may supplement the previously described factors which contribute to sickle cell crises.

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