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Objective: The objective of this study was to investigate the hemodynamic parameters of type II endoleaks (T2ELs) to predict sac expansion using four-dimensional flow-sensitive magnetic resonance imaging (4D-flow MRI) analysis., Methods: Patients who underwent endovascular aneurysm repair (EVAR) and were diagnosed with a T2EL were included in the study. Using 4D-flow MRI at 7 days, the peak flow velocity and amplitude of dynamics of blood flow per minute were measured in each T2EL vessel. The peak flow velocity was defined as the maximum of the absolute value of the blood flow velocity. The amplitude of dynamics of blood flow in the tributary arteries was defined as the sum of the absolute values of the inflow and outflow volume in each vessel. The amplitude of dynamics of blood flow in the tributary arteries per sac was calculated in each sac. The aneurysm sac diameter was measured by computed tomography (CT) at 1 year. The patients were divided into two groups according to the presence or absence of sac expansion., Results: Of 155 patients who underwent EVAR, both CT angiography and 4D-flow MRI were performed in 107 patients at 7 days after EVAR. Among them, 39 (36.4%) were found to have a T2EL, of whom 28 were re-evaluated with CT angiography and 4D-flow at 1 year; 7 patients had expanding sacs (expanding group), whereas 21 had nonexpanding sacs (not-expanding group). At 7 days, 28 patients had 80 T2EL vessels detected by 4D-flow MRI, of which 39 vessels (48.8%) had stopped flowing at 1 year (transient vessels); 41 vessels (51.3%) had sustained flow (persistent vessels). The persistent vessels had significantly larger peak flow velocity and amplitude of dynamics of blood flow. The comprehensive analysis of T2EL vessels per sac identified that the amplitude of dynamics of blood flow in the tributary arteries per sac was significantly higher in the expanding group than in the not-expanding group. A receiver operating characteristic curve analysis revealed that the sensitivity and specificity of sac enlargement at a cutoff value of 3750 mm 3 /min were 85.7% and 76.2%, respectively., Conclusions: The fate of aneurysm sacs with T2ELs after EVAR has remained difficult to predict. A comprehensive analysis of concurrent multiple T2EL vessels using 4D-flow MRI analysis may enable prediction of the sac expansion after EVAR., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Pancreaticoduodenal artery (PDA) aneurysm associated with celiac axis compression by the median arcuate ligament (MAL) is a rare disorder, but may be lethal if ruptured. Therefore, prophylactic surgical treatments need to be considered when MAL compresses the celiac axis. We herein report the usefulness of an arterial flow analysis for objectively evaluating this pathophysiology under four-dimensional flow-sensitive magnetic resonance imaging (4D-flow MRI). Celiac artery stenosis was incidentally found under contrast-enhanced CT in a 50-year-old woman with symptomatic solitary pancreatic insulinoma. Under 4D-flow MRI, retrograde blood flow and aberrant wall shear stress were detected in the pancreaticoduodenal artery arcade. After obtaining informed consent, enucleation for insulinoma concomitant with MAL dissection was performed. Hypoglycemic attack completely resolved immediately after surgery. One month after surgery, 4D-flow MRI revealed normalized vectorial flow and wall shear stress in the PDA arcade without hypoglycemic attack. 4D-flow MRI is a very useful and non-invasive modality for objectively evaluating visceral artery hemodynamics.

Objectives: Many pancreaticoduodenal artery (PDA) aneurysms are associated with celiac artery (CA) stenosis. The pathogenesis of PDA aneurysm may be associated with hemodynamic changes due to CA stenosis/occlusion. The aim of this study was to assess the hemodynamic changes of celiaco-mesenteric anastomosis in patients with PDA aneurysms concomitant with CA occlusion using four-dimensional flow-sensitive magnetic resonance imaging (4D-Flow)., Methods: 4D-Flow was performed preoperatively on five patients. Seven age- and sex-matched individuals were used as controls. Hemodynamic parameters such as flow volume and maximum flow velocity in PDAs, gastroduodenal arteries, common hepatic arteries, and superior mesenteric arteries were compared between both groups. Wall shear stress (WSS) and oscillatory shear index (OSI) were mapped in both groups., Results: In the patient group, 4D-Flow identified retrograde flow of both gastroduodenal arteries and common hepatic arteries. Heterogeneous distribution patterns of both WSS and OSI were identified across the entire PDA in the patient group. OSI mapping showed multiple regions with extremely high OSI values (OSI > 0.3) in all patients. All PDA aneurysms, which were surgically resected, were atherosclerotic., Conclusions: 4D-Flow identified hemodynamic changes in celiaco-mesenteric arteries in patients with PDA aneurysms with concomitant CA occlusion. These hemodynamic changes may be associated with PDA aneurysm formation., (© 2013 Published by Elsevier Ltd on behalf of European Society for Vascular Surgery.)

Purpose: To assess the pelvic circulation during abdominal aortic aneurysm (AAA) repair by measuring the inferior mesenteric artery stump pressure (IMA-SP), penile blood flow, and gluteal blood flow., Methods: Twenty males were selected for this study. An aorto-bi-common iliac arteries (CIA) graft replacement was performed in ten patients (Group Bi-CIA). An aorto-right-CIA/left-external iliac artery (EIA) graft replacement was performed in five (Group Lt-EIA). The other five underwent an aorto-right-EIA/left-CIA anastomosis (Group Rt-EIA). The right graft limb was anastomosed first, followed by the left limb in all of the patients. Pelvic circulation was monitored during aortic reconstruction, including the IMA-SP index (IMA-SPI), penile brachial pressure index (PBI) by pulse-volume plethysmography, and gluteal tissue oxygenation metabolism with near-infrared spectroscopy by monitoring the gluteal tissue oxygenation index (TOI) bilaterally., Results: The PBI and bilateral gluteal TOI became depressed in all patients during proximal aortic clamping. However, there was no significant change in IMA-SPI in each group. The PBI and bilateral gluteal TOI in all groups recovered to the baseline values after completion of bilateral graft limb anastomosis., Conclusions: IMA-SPI is likely to reflect collateral circulation mainly from the superior mesenteric artery. The penile blood flow and bilateral gluteal blood flow therefore seem to be supplied via the bilateral hypogastric arteries or the profunda femoris arteries.

Objectives: Venodynamics and lymphodynamics may interact as an inseparable and mutually dependent dual outflow system. This study investigated the effect of surgical treatment on lower limb lymph flow in patients with varicose veins., Methods: Thirty-nine patients with varicose veins in the lower limb (28 patients with unilateral limb, 11 patients with bilateral limb), who demonstrated great saphenous vein reflux, were investigated with air-plethysmography and indocyanine green (ICG) fluorescence lymphography before surgical treatment and 6 months later. Fifteen healthy volunteers participated in this study as a control. With air-plethysmography, venous volume (VV) and venous filling time were measured. Venous filling index (VFI) was calculated. For ICG lymphography, 0.3 mL of ICG (0.5%) was subcutaneously injected at the dorsum of the foot. After the injection, fluorescent image of ICG dye was traced on real-time video images using a near-infrared camera system. The interval until the dye reached the knee was measured (transit time [TT]) in a standing position, which was previously demonstrated to correlate with the interval measured using dynamic isotope lymphoscintigraphy., Results: In CEAP clinical stage venous disease, TT in patients with C4 approximately 6 and C2 approximately 3 was significantly longer than that in the control group (587 +/- 97 seconds, 484 +/- 82 seconds, 252 +/- 29 seconds, respectively, mean +/- SD, P < .01). Among all limbs with varicose veins, there were correlations between TT and VV (Pearson r = 0.31, P < .01), between TT and VFI (Pearson r = 0.48, P < .01). All patients underwent great saphenous vein stripping. Six months later, the venous clinical severity score significantly improved with significant reductions in both VV and VFI values. TT 6 months postoperatively was also significantly shorter than that before surgical treatment (501 +/- 67 seconds, 340 +/- 38 seconds, respectively, mean +/- SD, P < .01)., Conclusions: Varicose veins could affect lymphatic function and delay lymphatic flow in the lower limbs. Derangement of lymph flow may correlate with the severity of clinical venous disease and/or the magnitude of venous reflux, which could be reversible with surgical treatment of venous incompetence.

Perfluorochemicals (PFC) are chemical substances that have a high solubility for oxygen. This study investigated the effect of peritoneal lavage with oxygenated PFC (O2-PFC) against hemorrhagic shock and resuscitation (HS/R). Male Sprague-Dawley rats were anesthetized and bled to a mean arterial pressure (MAP) of 30 to 35 mmHg for 120 min. The animals then were resuscitated over 20 min with an infusion of shed blood. Peritoneal lavage was performed by inflow and outflow of the PFC solution at 80 mL/h during the shock-resuscitation period. Rats were divided into four groups. Group I, HS without peritoneal lavage; Group II, HS with nitrogenated PFC (N2-PFC) lavage; Group III, HS with O2-PFC lavage; and Group IV, sham-operated rats. Seven of seven (100%) rats in Group IV and six of seven (85.7%) rats in Group III survived for 48 h, and one of seven (14.3%) rats in Group I and zero of seven rats in Group II survived (P < 0.01). In Group III rats, metabolic acidosis (assessed by blood gas analysis) and depression of intestinal blood flow (assessed by laser Doppler flowmetry) during HS were markedly ameliorated in comparison with those in Group I or Group II rats. The elevation of plasma TNF-alpha and IL-6 after HS/R were also attenuated in Group III. Histological study showed that O2-PFC lavage significantly decreased the degree of intestinal mucosal damage. We conclude that treatment with O2-PFC lavage ameliorated HS/R-induced metabolic acidosis and intestinal damage, which was associated with better mortality, possibly by preserving microvascular perfusion and maintaining oxygen metabolism.

We characterized the detailed hemodynamics of fetal blood pressure, heart rate, common umbilical blood flow, and femoral blood flow responses to partial compression of the umbilical cord and tested the hypothesis that repeated cord compression modulates fetal cardiovascular responses in 10 chronically instrumented fetal sheep at approximately 130 days of gestation. In five fetuses (group I), partial compression of the umbilical cord was induced 12 times, each for 5 min at 15-min intervals. Each cord compression reduced common umbilical blood flow by 50% and produced modest falls in fetal pH (7.33 +/- 0 to 7.29 +/- 0) and arterial PO2 (21.1 +/- 0.2 to 16.8 +/- 0.2 mmHg) and a mild increase in arterial PCO2 (49.9 +/- 0.5 to 54.9 +/- 0.4 mmHg). Sham experiments were performed in five other fetuses (group II). Second-by-second analysis of group I fetal cardiovascular data revealed a clear biphasic response to partial cord compression. Phase I (1st min of cord compression) was characterized by a rapid bradycardia and a rapid femoral vasoconstriction (primary response); phase II (minutes 2-5 of cord compression) was characterized by a delayed bradycardia and a return of femoral vascular resistance toward baseline (secondary response). Repeated cord compression abolished the primary, but not the secondary, cardiovascular responses. These results demonstrate that fetal cardiovascular responses to stress may be modified by preexposure to repeated intrauterine challenges.