Lower extremity volumetric arterial blood flow in normal subjects

Holland, Christy K.; Jw, Brown; Scoutt, Leslie M.; Taylor, Kenneth J. W.

doi:10.1016/s0301-5629(98)00103-3

Cited by 91 publications

(73 citation statements)

References 23 publications

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“…The flow rates determined in this study ( Table 1) are in good agreement with the analogous values obtained by Wehrli et al [28] and Holland et al [29]. The latter paper reported Doppler ultrasound measurements of the popliteal artery mean volume flow to be 72 mL/min (our observation, 76 mL/min).…”

Section: Discussionsupporting

confidence: 92%

Quantitative Flow Relaxographic Angiography

Lee¹

2012

OJRad

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A powerful method, termed flow relaxography, allowing the practical and accurate determination of the water proton MR signal relaxation time distributions has been recently introduced with a phantom, having both flowing and nonflowing water. It was demonstrated that this method can discriminate the signals from the flowing and non-flowing spins, since flow affects the apparent T 1 ( T ) value. In this report, it is demonstrated that this technique is effective also in the human leg in vivo. Flow relaxographic angiography is presented for the first time. This technique promises to accomplish the twin goals of flow studies in medical MRI, to display vascular anatomy and measure its blood flow rate, in the same image.

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Section: Discussionsupporting

confidence: 92%

Quantitative Flow Relaxographic Angiography

Lee¹

2012

OJRad

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“…Small changes in intravenous pressure owing to changes in blood flow will have an effect on venous volume, and unstressed venous volume may thus decrease, as shown in the extremities using ischemic handgrip or LBNP (17,39). Basal arterial inflow to the lower limb seems to be similar in women and men (21,28), and a majority of studies have found no sex difference in arterial vasoconstriction (9,10,13,58), although men may respond with greater vasoconstriction during LBNP (7). A greater vasoconstriction in men, however, would have led to an underestimation of the differences in capacitance response in the present study.…”

Section: Discussionmentioning

confidence: 95%

Sex-related effects on venous compliance and capillary filtration in the lower limb

Lindenberger

Länne²

2007

American Journal of Physiology-Regulatory, Integrative and Comp

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Recent studies in humans have suggested sex differences in venous compliance of the lower limb, with lower compliance in women. Capillary fluid filtration could, however, be a confounder in the evaluation of venous compliance. The venous capacitance and capillary filtration response in the calves of 12 women (23.2 Ϯ 0.5 years) and 16 men (22.9 Ϯ 0.5 years) were studied during 8 min lower body negative pressure (LBNP) of 11, 22, and 44 mmHg. Calf venous compliance is dependent on pressure and was determined using the first derivative of a quadratic regression equation that described the capacitance-pressure relationship [compliance ϭ ␤ 1 ϩ (2 ⅐ ␤2 ⅐ transmural pressure)]. We found a lower venous compliance in women at low transmural pressures, and the venous capacitance in men was increased (P Ͻ 0.05). However, the difference in compliance between sexes was reduced and not seen at higher transmural pressures. Net capillary fluid filtration and capillary filtration coefficient (CFC) were greater in women than in men during LBNP (P Ͻ 0.05). Furthermore, calf volume increase (capacitance response ϩ total capillary filtration) during LBNP was equivalent in both sexes. When total capillary filtration was not subtracted from the calf capacitance response in the calculation of venous compliance, the sex differences disappeared, emphasizing that venous compliance measurement should be corrected for the contribution of CFC. lower body negative pressure; capillary filtration coefficient; venous capacitance THE VENOUS SECTION OF THE cardiovascular system can be looked upon as a voluminous blood reservoir (70% of total blood volume), designed to preserve a proper inflow of blood into the heart during various cardiovascular adjustments. Thus central venous pressure and filling of the heart may be maintained at a fairly stable level, despite variations in venous blood volume (49). During upright posture, however, the pooling of blood in the veins of the lower part of the body decreases central blood volume and venous return (4, 5, 16). The venous compartment in the legs, rather than the pelvic or abdominal region, seems to have a hemodynamic impact during lower body negative pressure (LBNP) (16), and in studies on men, a greater calf venous compliance has been linked to an increased venous capacitance response with a concomitant reduction in central blood volume (44,56). This, in turn, elicits an increased sympathetic response with higher peripheral resistance and increased heart rate (4, 5, 10, 16, 44, 58). Thus venous compliance of the lower limb may have an impact on cardiovascular responses to orthostatic stress and orthostatic tolerance, although there might be differences between sexes confounding such a link (4).Women are more susceptible to orthostatic stress than men (4,10,13,40,51,58), and in accordance with some findings in the arterial tree, it may be hypothesized that women have greater venous compliance in the lower limbs predisposing to orthostatic intolerance (52). This seems to be refuted however, by recent fi...

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“…The blood velocity was measured five times at rest, and during recovery ( Fig. 1) and calculated by integrating the outer envelope of the maximum velocity values in the flow profile (Leyk et al, 1994;Isnard et al, 1996;Robergs et al, 1997;Holland et al, 1998;Osada et al, 1999;. The average value was determined after tracing 3 or 4 clear and successive signals following cardiac cycles for this vessel at each measurement point.…”

Section: Fbf Measurementsmentioning

confidence: 99%

Post-exercise Hyperemia after Ischemic and Non-ischemic Isometric Handgrip Exercise

Osada

Katsumura

Murase

et al. 2003

J. Physiol. Anthropol.

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Post-exercise related time course of muscle oxygenation during recovery provides valuable information on peripheral vascular disease. The purpose of the present study was to examine post-exercise hyperemia (forearm blood flow; FBF, Doppler ultrasound) assessed by peak FBF, excess FBF and the time constant for FBF (FBF Tc ) following isometric handgrip exercise (IHE). Post-exercise hyperemia was assessed in an ischemic and non-ischemic state at different exercise intensities and durations. Peak FBF and excess FBF were defined as the maximum FBF during recovery, and the total amount of FBF volume, respectively. FBF Tc represents the time to reach approximately 37% of the change in FBF between peak FBF and resting FBF (delta peak FBF). Ten subjects performed IHE at "10% and 30% maximum voluntary contraction (MVC)" for 2 min with or without arterial occlusion (AO), followed by 2 min of AO alone (Study I). In Study II, six subjects performed 30%MVC-IHE with AO for "100%, 66%, 33% and 10% of the exhausted exercise duration" (time to exhaustion). In Study I, although peak FBF and excess FBF were significantly higher in ischemic than non-ischemic IHE for both 10% and 30%MVC (pϽ0.05), FBF Tc was similar in the ischemic and non-ischemic conditions. The peak FBF, excess FBF and FBF Tc were all significantly higher at 30% than at 10%MVC (pϽ0.05). In Study II, the peak FBF and excess FBF increased linearly compared to the absolute and relative exercise durations for ischemic IHE. FBF Tc increased exponentially when compared to the absolute and relative exercise durations. These data suggest the ischemic exercise has a larger hyperemic response compared to the non-ischemic exercise. In conclusion, the peak FBF, excess FBF and FBF Tc seen during post-exercise hyperemia are closely correlated with exercise intensity and duration, not only in non-ischemic, but also in the ischemic exercise. In combination with the ischemic exercise, these parameters could potentially prove to be valuable indicators of peripheral vascular disease.

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Lower extremity volumetric arterial blood flow in normal subjects

Cited by 91 publications

References 23 publications

Quantitative Flow Relaxographic Angiography

Quantitative Flow Relaxographic Angiography

Sex-related effects on venous compliance and capillary filtration in the lower limb

Post-exercise Hyperemia after Ischemic and Non-ischemic Isometric Handgrip Exercise

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