Assessing the hemodynamic contribution of capillaries, arterioles, and collateral arteries to vascular adaptations in arterial insufficiency

Arciero, Julia; Lembcke, Lauren; Burch, Myson C.; Franko, Elizabeth; Unthank, Joseph L.

doi:10.1111/micc.12591

Cited by 5 publications

(11 citation statements)

References 59 publications

(174 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While several experimental studies have observed adaptations in collateral arteries and/or the distal microvasculature (arterioles and capillaries) following a major arterial occlusion on an acute time frame (see summary in), a comprehensive understanding of the relative significance of these adaptations is missing. In particular, previous studies that investigated the redistribution of vascular resistances post‐occlusion and that demonstrated the importance of collateral arteries were based solely on hemodynamic calculations and did not reveal the underlying factors that induced these changes in the vasculature. The results of this study provide a mechanistic explanation for the contributions of various vascular responses following an occlusion and identify the importance of the shear response in collateral arteries and the metabolic response in the distal microcirculation when compensating for an occlusion (Figure ).…”

Section: Discussionmentioning

confidence: 99%

“…The present study also offers an explanation for the reduced ability to compensate underexercising conditions that has been noted by other investigations . The model predicts that in the occluded case, the collaterals and arterioles are fully dilated before oxygen demand even reaches a level that corresponds to exercise.…”

Section: Discussionmentioning

confidence: 99%

“…Pressure entering the network from the aorta (

P_{a}

) is set to 140 mmHg, which corresponds to the mean arterial pressure in rats measured by Ziegler et al Venous pressure at the end of the calf (

P_{v}

) is assumed to be zero. As defined in Arciero et al,

P_{1} = 0.96 P_{a}

P_{distal} = 0.90 P_{a}

, and

P_{2} = 0.93 P_{a}

P_{3}

is chosen to be 75% of femoral pressure and

P_{4}

is assumed to be 28% of femoral pressure based on pressure values in pre‐capillary arterioles reported by Bohlen et al…”

Section: Methodsmentioning

confidence: 99%

“…Unthank et al used a similar circuit model to calculate resistances immediately and one week following ligation of the rat femoral artery . Arciero et al used an electrical circuit modeling framework to establish the necessity for collateral arterial dilation for flow restoration. However, none of these models included mechanistic explanations for the observed changes in vascular resistances.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Modeling acute blood flow responses to a major arterial occlusion

et al. 2020

Self Cite

View full text Add to dashboard Cite

Objective The development of earlier and less invasive treatments for peripheral arterial disease requires a more complete understanding of vascular responses following a major arterial occlusion. A mechanistic model of the vasculature of the rat hindlimb is developed to predict acute (immediate) changes in vessel diameters and smooth muscle tone following femoral arterial occlusion. Methods Vascular responses of collateral arteries and distal arterioles to changes in pressure, shear stress, and metabolism are assessed before and after occlusion. The effects of exercise are also simulated and compared with venous flow measurements from WKY rats. Results The model identifies collateral arteries as the primary contributors to flow compensation following occlusion. Increasing the number of capillaries has minimal effect on blood flow while increasing the number of collateral arteries significantly increases flow, since the primary site of resistance shifts upstream to the collateral arteries following occlusion. Despite significant collateral dilation, calf flow remains below pre‐occlusion levels and the deficit becomes more severe with increased activity. Conclusions Although unable to compensate fully for an occlusion, the model demonstrates the importance of the shear response in collateral arteries and the metabolic response in the distal microcirculation in acute adaptations to a major arterial occlusion.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

“…Pressure entering the network from the aorta (

P_{a}

) is set to 140 mmHg, which corresponds to the mean arterial pressure in rats measured by Ziegler et al Venous pressure at the end of the calf (

P_{v}

) is assumed to be zero. As defined in Arciero et al,

P_{1} = 0.96 P_{a}

P_{distal} = 0.90 P_{a}

, and

P_{2} = 0.93 P_{a}

P_{3}

is chosen to be 75% of femoral pressure and

P_{4}

is assumed to be 28% of femoral pressure based on pressure values in pre‐capillary arterioles reported by Bohlen et al…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Modeling acute blood flow responses to a major arterial occlusion

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Previous theoretical studies identified the primary role of collateral vessels in flow compensation following major arterial occlusion 9 and simulated vascular responses to occlusion on an acute time frame. 10 The study by Zhao et al 10 included a mechanistic description of flow regulation but did not allow for structural adaptation, and thus blood flow compensation was limited.…”

mentioning

confidence: 99%

Modeling acute and chronic vascular responses to a major arterial occlusion

et al. 2021

Self Cite

View full text Add to dashboard Cite

Peripheral arterial disease (PAD) is an atherosclerotic pathology that affects approximately 8-12 million individuals in the United States 1 and is characterized by either full or partial occlusion of an artery in the peripheral circulation. Occlusion of an artery prevents sufficient blood flow from reaching dependent tissue regions supplied by the artery, which can physically manifest as intermittent claudication or critical limb ischemia. 2 These symptoms can lead to increased mortality or a diminished quality of life if PAD is not diagnosed and treated effectively. 1 While surgery is the primary treatment for PAD, less invasive PAD treatments are needed. Developing less invasive treatment methods requires a thorough understanding of the effects of arterial occlusion on the surrounding vascular network, as well as knowledge of the intrinsic mechanisms that generate flow compensation without medical intervention.

show abstract

Peristenotic Collateral Circulation in Atherosclerotic Renovascular Disease

et al. 2020

View full text Add to dashboard Cite

The significance of peristenotic collateral circulation (PCC) development around a stenotic renal artery is unknown. We tested the hypothesis that PCC is linked to loss of kidney function and recovery potential in patients with atherosclerotic renovascular disease (ARVD). Thirty-four patients with ARVD were assigned to medical-therapy with or without revascularization based on clinical indications. The PCC was visualized using multidetector computed tomography and defined relative to segmental arteries in patients with essential hypertension. PCC number before and 3 months after treatment was correlated with various renal parameters. Thirty-four stenotic kidneys from 30 patients were analyzed. PCC number correlated inversely with kidney volume. ARVD–stenotic kidneys with baseline PCC (collateral ARVD [C-ARVD], n=13) associated with elevated 24-hour urine protein and stenotic kidney vein level of tumor necrosis factor-α, lower single-kidney volume and blood flow, and greater hypoxia than in stenotic kidneys with no PCC (no collateral ARVD [NC-ARVD], n=17). Revascularization (but not medical-therapy alone) improved stenotic kidney function and reduced inflammation in both NC-ARVD and C-ARVD. In C-ARVD, revascularization also increased stenotic kidney volume, blood flow, and oxygenation to levels comparable to NC-ARVD, and induced PCC regression. However, revascularization improved systolic blood pressure, plasma renin activity, and filtration fraction only in NC-ARVD. Therefore, patients with C-ARVD have greater kidney dysfunction, atrophy, hypoxia, and inflammation compared with patients with NC-ARVD, suggesting that PCC does not effectively protect the stenotic kidney in ARVD. Renal artery revascularization improved in C-ARVD stenotic kidney function, but not hypertension or renin-angiotensin system activation. These observations may help direct management of patients with ARVD.

show abstract

Assessing the hemodynamic contribution of capillaries, arterioles, and collateral arteries to vascular adaptations in arterial insufficiency

Cited by 5 publications

References 59 publications

Modeling acute blood flow responses to a major arterial occlusion

Modeling acute blood flow responses to a major arterial occlusion

Modeling acute and chronic vascular responses to a major arterial occlusion

Peristenotic Collateral Circulation in Atherosclerotic Renovascular Disease

Contact Info

Product

Resources

About