Inferior Vena Cava Occlusion Research Articles

Dynamic right and left ventricular interactions in the pig.

What is the central question of this study? Are the mechanisms that cause ventricular interdependence different when due to primary right to left ventricular pressure loading? What is the main finding and its importance? An instantaneous selective increase in aortic pressure causes an immediate increase in right ventricular end-systolic pressure independent of the pericardium, whereas a selective increase in pulmonary artery pressure decreases left ventricular diastolic compliance owing to a subsequent increasing right ventricular end-diastolic volume as a function of an intact pericardium limiting biventricular volume. Changes in contraction synchrony of either ventricle do not appear to be causing these effects. I characterized the dynamic factors determining ventricular interdependence with and without the pericardium. I measured right (RV) and left ventricular (LV) pressures and volumes simultaneously using conductance catheters in seven pentobarbitone-anaesthetized open-chested 5- to 7-week-old piglets. I studied these effects during apnoea, inferior vena caval occlusion and rapid partial aortic and pulmonary arterial occlusions. Conductance catheter-defined long-axis regional volumes were assessed to define regional contractile synchrony. Closed-pericardium measures were made from an initial (baseline) volume, then after two 20mlkg-1 fluid loads followed by an open-pericardium step. Baseline RV and LV volumes were similar. Aortic occlusion increased LV pressures and volumes and RV end-systolic pressure such that RV end-systolic elastance increased without changes in RV contraction synchrony, not affected by the pericardium. Pulmonary artery occlusion increased RV end-systolic pressure but not end-systolic volume. On the subsequent beat, RV end-diastolic pressure increased, whereas LV end-diastolic volume and diastolic compliance decreased. These effects were attenuated by opening the pericardium. Contraction synchrony across longitudinal segments was unaltered by either aortic or pulmonary artery occlusion. I conclude that the determinants of systolic and diastolic ventricular interdependence are different. Increasing RV pressures causes diastolic RV-to-LV interdependence, decreasing LV diastolic compliance and dependent on an intact pericardium. An increase in LV end-systolic pressure increases RV end-systolic elastance independent of the pericardium and has a minimal effect on RV diastolic function or contraction synchrony.

Inferior Vena Cava Constriction After Liver Transplantation Is a Severe Complication Requiring Individually Adapted Treatment: Report of a Single-Center Experience

BackgroundReports on vena cava occlusion after liver transplantation (LT) are rare, but this finding represents a severe complication in the early postoperative period. In the context of the complex presentation of a patient after LT, symptoms are often misinterpreted and can be subtle.Material/MethodsIn our cohort of 138 LTs performed between 2014 and 2017 at our University’s Transplantation Department, 117 transplantations were valid for further analysis after exclusion of pediatric transplantations and transplants with primary non-function grafts. In 101 cases (73%), patients received a deceased-donor full-size organ. Living-donor LT was performed in 8 patients (6.4%) and 8 patients (6.4%) received a split graft. We report on 6 patients who had inferior vena cava (IVC) occlusion and summarize the treatment choices.ResultsIn our series, patients with positive findings (age 38–70 years) received an orthotopic full-size deceased-donor graft with end-to-end IVC anastomosis. In the subsequent period, imaging revealing IVC occlusion was done on a follow-up basis (n=2), due to dyspnea (n=1), and for progressive ascites (n=2). In 3 cases, a thrombus was found. We give detailed information on our treatment options from interventional treatment to transcardial thrombus removal and anastomosis augmentation.ConclusionsIVC constriction and subsequent thrombosis are severe complications after LT that require individually adapted treatment in specialized centers. Since patients often present with subclinical symptoms, vascular diagnosis should be performed early to detect caval anastomosis pathologies. Despite regular ultrasonography, we favor CT and cavography for subsequent quantification. We also review the literature on IVC occlusion after LT.

Initial Series of Robotic Segmental Inferior Vena Cava Resection in Left Renal Cell Carcinoma With Caval Tumor Thrombus

OBJECTIVETo present our preliminary experience of robotic left radical nephrectomy (LRN) and segmental inferior vena cava (IVC) resection without caval replacement for left renal cell carcinoma (RCC) with inferior vena cava tumor thrombus. MATERIALS AND METHODSBetween 2017 and 2018, 7 patients underwent segmental IVC resection and LRN robotically. All patients underwent preoperative cavography, demonstrating complete IVC occlusion. Computed tomography-based 3-dimensional reconstruction revealed sufficient collateralization of the IVC and right renal vein (RRV). The cephalic IVC was circumferentially resected and ligated just below the second porta hepatis. The caudal IVC was circumferentially resected above the RRV with preservation of the major collaterals. The RRV was not dissected during the procedure to avoid compromising its neocollaterals. The IVC portion between the RRV and the second porta hepatis was removed en bloc with the tumor thrombus, and the LRN was performed. RESULTSAll cases were successfully performed by robotic surgery without conversion. Median operative time was 420 minutes. Median intensive care unit stay was 3 days. Four grade Ⅱ complications occurred in 2 patients. One patient had mild LEE postoperatively and recovered without special medication. Median preoperative and 3-6 months follow-up serum creatinine was 118.7 μmol/L and 135.2 μmol/L, respectively. No patient needed dialysis postoperatively. One case occurred disease progression. No patient died during the follow-up period. CONCLUSIONRobotic segmental IVC resection for left RCC with inferior vena cava tumor thrombus is feasible in well-selected cases. Three-dimensional reconstruction and cavography are helpful in the preoperative evaluation of neocollaterals in patients with suprarenal IVC occlusion.

Dynamic Arterial Elastance as a Ventriculo-Arterial Coupling Index: An Experimental Animal Study.

Dynamic arterial elastance (Eadyn), the ratio between arterial pulse pressure and stroke volume changes during respiration, has been postulated as an index of the coupling between the left ventricle (LV) and the arterial system. We aimed to confirm this hypothesis using the gold-standard for defining LV contractility, afterload, and evaluating ventricular-arterial (VA) coupling and LV efficiency during different loading and contractile experimental conditions. Twelve Yorkshire healthy female pigs submitted to three consecutive stages with two opposite interventions each: changes in afterload (phenylephrine/nitroprusside), preload (bleeding/fluid bolus), and contractility (esmolol/dobutamine). LV pressure-volume data was obtained with a conductance catheter, and arterial pressures were measured via a fluid-filled catheter in the proximal aorta and the radial artery. End-systolic elastance (Ees), a load-independent index of myocardial contractility, was calculated during an inferior vena cava occlusion. Effective arterial elastance (Ea, an index of LV afterload) was calculated as LV end-systolic pressure/stroke volume. VA coupling was defined as the ratio Ea/Ees. LV efficiency (LVeff) was defined as the ratio between stroke work and the LV pressure-volume area. Eadyn was calculated as the ratio between the aortic pulse pressure variation (PPV) and conductance-derived stroke volume variation (SVV). A linear mixed model was used for evaluating the relationship between Ees, Ea, VA coupling, LVeff with Eadyn. Eadyn was inversely related to VA coupling and directly to LVeff. The higher the Eadyn, the higher the LVeff and the lower the VA coupling. Thus, Eadyn, an easily measured parameter at the bedside, may be of clinical relevance for hemodynamic assessment of the unstable patient.

Acute Administration of Gut Microbial Metabolites Reduces Blood Pressure and Cardiac Contractility

Metabolites produced by the gut microbiota can affect host physiology; one class of these metabolites are short chain fatty acids (SCFAs). Prior work by our laboratory has shown that intravenous administration of SCFAs causes acute hypotension (Pluznick, Protzko et al. 2013) and that treating vessels with SCFAs ex vivo results in vasorelaxation (Natarajan, Hori et al. 2016). To expand upon these findings, we performed IP injections of acetate in mice that were implanted with DSI telemetry transmitters to monitor mean arterial pressure (MAP) and heart rate (HR) in real time. Sodium acetate (acetate is the most abundant SCFA in the circulation) was given at a 1g/kg dose via IP, which elevates plasma acetate by 3–4 fold over baseline (Shubitowski, Poll et al. 2019). Upon sodium acetate IP injection, we observed a rapid and reproducible drop in MAP (−49.2 +/− 10.7 mmHg maximum drop, n=10 males + females, p<0.05) when compared to an IP injection of saline. Surprisingly, in addition to a significant depression of MAP, mice injected with acetate also showed a significant depression in HR (−257.6 +/− 55.8 bpm maximum drop, p<0.05). IP injections of propionate and butyrate, two other SCFA microbial metabolites, had similar depressive effects on MAP and HR, but lactate (control) had no effect. Had SCFAs been solely acting on the vasculature, we would have expected the baroreflex to increase HR. To determine if acetate was having a direct cardiac effect, we used isolated perfused Langendorff hearts from mice. During acetate infusion, Langendorff hearts showed a significant decrease in HR, suggesting a direct mechanism of action (353.8 +/− 39.5 bpm baseline vs 274.6 +/− 21.3 bpm acetate n=5, p<0.05), however the HR drop was on a much slower time scale than seen in vivo. To further probe the effects of acetate on cardiac contractility, pressure volume loops were performed on anesthetized mice and acetate was administered by IP. Inferior vena cava occlusion after acetate IP showed a significant decrease in Preload Recruitable Stroke Work (PRSW, 73.06 +/− 20.98 vs. 49.06 +/− 22.11 mmHg*μl baseline vs acetate, n=7 males + females, p<0.05) and end‐systolic elastance (Ees, 3.493 +/−1.139 vs. 1.519 +/− 0.5781 mmHg/μl baseline vs. acetate, n=7 males + females, p<0.05), two parameters of load‐independent cardiac contractility. Finally, pre‐treatment of conscious mice with cardioselective β antagonist metoprolol blocked the acetate mediated drop in HR in mice implanted with telemetry devices, but the drop in MAP remained intact. We hypothesize that acetate acts independently on the peripheral vasculature and the cardiac muscle, with direct and indirect effects on cardiac function. Both components are likely contributing to the MAP and HR effects seen in whole animals. Together these data demonstrate a previously unknown and potentially detrimental effect of short chain fatty acids on cardiac function.Support or Funding InformationF31HL144061, R01HL128512, R01DK107726

Determinants of Diastolic Dysfunction in Swine with HFpEF Arising From Transient Repetitive Left Ventricular Pressure Overload

ObjectiveWe recently demonstrated that swine subjected to 2‐weeks of repetitive pressure overload (RPO) exhibit adaptive myocardial remodeling in the absence of left ventricular (LV) hypertrophy. This remodeling is similar to that arising in many patients with heart failure and a preserved ejection fraction (HFpEF). While LV compliance is markedly reduced, the relative contribution of altered myocardial relaxation vs. passive myocardial properties to this is unclear. Accordingly, the objective of the present study was to determine how RPO affects passive myocardial stiffness and active myocardial relaxation, two key components of LV diastolic function.MethodsSwine (n=14) were subjected to 2‐weeks of RPO via daily infusions of phenylephrine (300 ug/min, 2 hours/day). Invasive measurements of LV performance were collected before and after RPO at rest and during alterations in loading conditions elicited by transient manipulation of venous return. To assess reversibility, a subset of animals (n=6) underwent repeat studies 2‐weeks after cessation of RPO. After the final study, myocardial tissue was collected from the LV free wall for post‐mortem assessment of calcium handling protein expression (western blot; n=8), passive myocardial stiffness (uniaxial tensile testing; n=3), and quantification of interstitial fibrosis (picrosirius red staining).ResultsCompared with baseline measurements, 2‐weeks of RPO did not significantly affect the LV relaxation time constant (Tau) or the rate of LV pressure change during isovolumic relaxation (dP/dtmin; Table ). Consistent with this observation, myocardial expression of calcium handling proteins SERCA (from 0.58±0.24 to 0.52±0.25, p=0.62), ryanodine receptor (from 0.37±0.17 to 0.36±0.14, p=0.99), and phospholamban (from 0.46±0.21 to 0.33±0.15, p=0.17) was not different following RPO vs. normal controls (n=8). However, assessment of LV performance under altered loading conditions revealed a significant increase in the LV stiffness coefficient (β) during IVC occlusion as well as the ΔEDP/ΔEDV ratio during rapid saline loading. These functional changes persisted for 2‐weeks following cessation of RPO and were accompanied by a significant increase in passive myocardial stiffness and interstitial fibrosis.ConclusionsThese results demonstrate that the reduction in LV compliance arising after RPO is not related to delayed active myocardial relaxation at rest or altered expression of sarcoplasmic reticulum calcium handling proteins. However, RPO elicits a persistent increase in passive myocardial stiffness that is likely mediated by interstitial collagen deposition. These passive diastolic properties may explain exercise intolerance in HFpEF patients despite normal resting hemodynamics and the absence of anatomic LV hypertrophy.Support or Funding InformationFunding Sources: The National Heart Lung and Blood Institute (HL‐061610), the American Heart Association (17SDG33660200), the National Center for Advancing Translational Sciences (UL1TR001412), the Department of Veterans Affairs (1IO1BX002659), the Community Foundation for Greater Buffalo, and the Albert and Elizabeth Rekate Fund in Cardiovascular Medicine. Baseline/Control RPO Cessation of RPO Tau (ms) 36.5 ± 1.6 35.9 ± 1.6 34.3 ± 1.7 dP/dtmin (mmHg/s) −2116 ± 369 −2301 ± 133 −2464 ± 272 Diastolic Stiffness Coefficient (β) 0.025 ± 0.003 0.054 ± 0.007 * 0.043 ± 0.009 * ΔEDP/ΔEDV During Saline Loading (mmHg/mL) 0.09 ± 0.02 0.21 ± 0.04 * 0.23 ± 0.03 * Ex Vivo Passive Stiffness (kPa) 77.8 ± 11.0 ‐‐‐ 131.0 ± 6.1 * Interstitial Fibrosis (%) 6.6 ± 0.7 12.9 ± 1.8 * 16.3 ± 1.1 * Values are mean ± SEM. *p<0.05 vs. Baseline/Control

A self-designed liver circle for on-demand Pringle's manoeuver in laparoscopic liver resection.

Background:Laparoscopic liver resection (LLR) allows minimal incisions and relatively quicker post-operative recovery, while intraoperative massive haemorrhage led to conversion to laparotomy. This study aimed to introduce a new, safe and convenient device to serve as Pringle's manoeuver according to the demand in LLR.Methods:A liver circle consisting of a hole and a round stem with an obtuse small head was made by medical silica gel. It was applied in LLR to perform on-demand Pringle's manoeuver and developed its function in inferior vena cava (IVC) occlusion. The time of performing Pringle's manoeuver by liver circle, extracorporeal tourniquet and endo intestinal clip under laparoscopic simulator and LLR was compared.Results:The liver circle was successfully applied to perform Pringle's manoeuver, IVC exposure and occlusion. It took less time in the occluding step of Pringle's manoeuver than the extracorporeal tourniquet (4.15 ± 0.35 s vs. 9.90 ± 1.15 s, P < 0.05) and the endo intestinal clip (4.15 ± 0.35 s vs. 47.91 ± 3.98 s, P < 0.05) under LLR. The total manipulating time for Pringle's manoeuver with liver circle remained the shortest, and the advantages were more obvious with increased frequencies of intermittent Pringle's manoeuver.Conclusion:The new-designed liver circle is more convenient compared to other techniques in performing Pringle's manoeuver, especially the intermittent Pringle's manoeuver in LLR. It can be used to perform on-demand hepatic blood inflow occlusion in every LLR by pre-circling the hepatoduodenal ligament to control bleeding during surgery. It can also be applied to expose the surgical field of vision and perform IVC occlusion to reduce intraoperative blood loss.

3:54 PM Abstract No. 88 Safety and efficacy of Gianturco tracheobronchial z-stent placement for recanalization in patients with inferior vena cava occlusion

To evaluate the technical success and safety of Gianturco Z-stent placement in patients with occlusion of the inferior vena cava (IVC). Between January 2010 and July 2019, a retrospective review was performed including patients who underwent placement of Gianturco tracheobronchial Z-stents (Cook Medical, Bloomington, IN) in the IVC for treatment of IVC occlusion. Indication for placement, technical success, primary patency, and clinical success as measured by symptomatic improvement were recorded. Patients received clinical follow-up and computed tomographic (CT) imaging for patency evaluation initially at 1 to 4 months and yearly thereafter. Z-stent placement was performed in the IVC of 20 patients (median, age, 47 years; range, 21-88 years; percent female, 50%). Indications for IVC stent placement consisted of non-malignant occlusions in 13 patients and malignant occlusions in 7 patients. Technical success was achieved in all patients; no procedure-related major adverse events were observed. Data on clinical success was available in 11 of 13 patients treated for non-malignant IVC occlusions at initial follow-up (mean follow-up length, 1.4 months; range, 1-2 months) demonstrating symptomatic improvement in 100% (11/11) of patients. Patency of IVC stents was maintained in 92.3% (12/13) of patients treated for non-malignant occlusions (mean follow-up length, 1.5 months; range, 1-4 months). Longer-term follow-up was available in 5 patients with non-malignant occlusions and all (5/5) demonstrated maintained patency of IVC stents (mean follow-up length, 21.8 months; range, 12-45 months). Of the patients treated for malignant IVC occlusion for whom data was available, symptomatic improvement was achieved in 100% (4/4 patients; median follow-up length, 3.5 months; range, 2-17 months) and patency of the IVC stent was maintained in 100% (5/5 patients; median follow-up length, 5 months; range, 2 weeks-19 months). Through available follow-up, off-label placement of Gianturco tracheobronchial Z-stents in the IVC appears safe for patients with both non-malignant and malignant occlusions. Long-term follow-up will be necessary in evaluating the efficacy and durability of the intervention.

Abstract No. 658 Exercise intolerance caused by chronic iliocaval venous occlusion: non-invasive quantitative assessment

Patients with chronic inferior vena cava (IVC) and bilateral iliac vein postthrombotic occlusion often report subjective decreased exercise tolerance that improves after stent reconstruction. We report preliminary results of the use of quantitative exercise testing to assess change in exercise tolerance occurring after venous reconstruction. The Institutional Review Board approved this retrospective study. Exercise testing before and after intervention was conducted in the Human Performance Laboratory (HPL): resting blood pressure, heart rate, body mass index (BMI), body composition, standard pulmonary function tests, and incremental maximal exercise testing (VO2 max test). Maximal exercise was defined as a plateau in the oxygen uptake, a respiratory exchange ratio (RER) greater than 1.1, or voluntarily termination of exercise. The VO2 max (mL/kg/min), maximum work (W) and total exercise time were analyzed. Percutaneous venous reconstruction was performed using standard techniques and stents. Results were reported as simple averages and percentages. Three male patients with chronic postthrombotic IVC and bilateral iliac venous occlusions were studied. Mean age 63 ± 8 years, mean duration of occlusion 36 ± 12 months. The interval between reconstruction and testing ranged from 2.5 to 11 months. All patients had stents in the infra-renal IVC to bilateral common femoral veins. No exercise instructions were provided to patients after stent reconstruction. Following venous reconstruction, the V02 max increased an average of 38.7%, the total work increased 74.4%, and the total exercise time increased 18.7%. Each individual lost weight, with an average decrease of 7.5%. Subjectively, all patients reported an increased exercise tolerance and decreased shortness of breath with exertion. Subjective impairment in exercise tolerance and improvement after venous reconstruction was quantitated in three patients with chronic postthrombotic occlusion of the IVC and bilateral iliac veins. HPL testing may be a useful additional objective tool in the study of patients with chronic ilio-caval occlusions.

Spine stabilization is a risk factor for the development of pelvic iliac vein lesions

BackgroundOpen lumbar spine stabilization surgery often requires mobilization of the left and right common iliac veins (CIVs) and the placement of plates and screws that can impinge on them. We reviewed our venography experience of the past 3 years to determine whether there is an association between spine stabilization surgery and the development of symptomatic iliac vein outflow lesions. MethodsA retrospective chart review of prospectively collected data from our electronic medical record system was performed to identify patients who underwent venography with or without venous stenting and had a history of previous lumbar spine stabilization. Patients' demographics, medical comorbidities, venograms, and intravascular ultrasound (IVUS) data were collected and analyzed. The senior author reviewed all venograms and IVUS images of patients with previous spine stabilization procedures. ResultsFrom January 2014 to April 2018, venography was performed in 1713 limbs in 1245 patients at the Center for Vascular Medicine. Of the 1245 patients, 18 patients had a history of lumbar spine stabilization procedures: five anterior-posterior and 13 posterior. Nine had single-level and eight had two- or three-level fusions. All 18 patients demonstrated pelvic lesions. These included 1 left CIV aneurysm, 5 left CIV stenoses, 3 bilateral CIV stenoses, 2 left CIV and inferior vena cava occlusions, and 2 external iliac vein stenoses. The aneurysm patient was treated with anticoagulation, 8 patients underwent stenting, 1 patient refused stenting because of relocation to another country, 1 inferior vena cava-CIV occlusion could not be crossed, fear of dislodging a thrombus and the proximity to a protruding posteriorly placed screw prevented stenting in 2 patients, and 4 patients had a venoplasty alone because of undersizing of a stenosis or missed lesions with IVUS after review by a blinded reviewer. Lesions in anterior lumbar interbody fusion patients were extremely stenotic, required predilation, and resulted in a residual stenosis requiring venoplasty at a second setting in one patient. ConclusionsLumbar spine stabilization surgery may be a risk factor for development of symptomatic venous outflow obstruction lesions. During venography and stenting in patients with anterior lumbar interbody fusion approaches, significant scarring may be encountered, resulting in a residual stenosis after stent placement. Predilation venoplasty, before stent deployment, is recommended to prevent stent migration. Furthermore, a history of spine stabilization surgery in patients presenting with pelvic symptoms, lower extremity pain or swelling, or post-thrombotic symptoms should prompt consideration of a pelvic venous duplex ultrasound examination to determine whether an iliac venous outflow lesion is present.

Inferior Vena Cava Reconstruction in Symptomatic Patients Using Palmaz Stents: A Retrospective Single-Center Experience

The use of stents for treating central venous occlusion is well described. Limited evidence exists related to Palmaz balloon-expandable stent use in inferior vena cava (IVC) reconstruction. We analyzed patency and complication rates after IVC reconstruction using Palmaz stents. From 2002 to 2019, 37 patients (mean age: 51year) underwent IVC reconstruction with 68 Palmaz stents. Indications were symptomatic chronic venous obstruction in the infrarenal (n=25) and intrahepatic (n=12) IVC. Demographic, operative, and imaging data were evaluated. Clinical data, abdominal CT, and/or duplex ultrasound were used to determine patency at follow-up. Restoration of caval patency was achieved in all patients, with complications in 2/37 (5.4%) patients (thrombus formation within the stent; stent embolization eight days after placement). Follow-up data were available for 27 patients. Primary patency was maintained through last follow-up in 19/27 (70%) patients (mean: 1.1year), with successful stent redilation performed in 6 patients. Mean duration of primary-assisted patency (n=5) was 1.2year. Late lumen loss was (n=13) was 40% during a mean time to follow-up of 2.0years. Primary patency in patients with occlusion secondary to malignancy was 109day (range: 1 day-1.0year), whereas primary patency in patients with occlusion from other etiologies was 1.1year (range: 2day-5.9year). The Kaplan-Meier analysis demonstrated primary and primary-assisted patency of 66% and 84%, respectively, at 24 and 48 months. Palmaz balloon-expandable stents for IVC reconstruction is feasible and effective for symptomatic IVC occlusion. Risk of stent migration was low.

Leiomyosarcoma of inferior vena cava

A 57-year-old female presented with intermittent abdominal pain and bilateral pedal oedema. She was diagnosed as leiomyosarcoma from inferior vena cava (IVC). Imaging suggested encasement and occlusion of infra-renal IVC. She had received palliative chemotherapy from elsewhere, with no regression. We excised the tumour. At 14 months after the surgery, she is disease-free. Surgery is the mainstay in the treatment of retroperitoneal sarcomas. Even locally advanced retroperitoneal sarcomas may be successfully managed with complete surgical resection. Reconstruction of resected IVC segment may be avoided in selected cases.

Intermittent Occlusion of the Superior Vena Cava Reduces Cardiac Filling Pressures in Preclinical Models of Heart Failure.

Congestion is a major determinant of clinical outcomes in heart failure (HF). We compared the acute hemodynamic effects of occlusion of the superior (SVC) versus the inferior vena cava (IVC) and tested a novel SVC occlusion system in swine models of HF. IVC occlusion acutely reduced left ventricular (LV) systolic and diastolic pressures, LV volumes, cardiac output (CO), and mean arterial pressure (MAP). SVC occlusion reduced LV diastolic pressure and volumes without affecting CO or MAP. The preCARDIA system is a balloon occlusion catheter and pump console which enables controlled delivery and removal of fluid into the occlusion balloon. At 6, 12, and 18h, SVC therapy with the system provided a sustained reduction in cardiac filling pressures with stable CO and MAP. Intermittent SVC occlusion is a novel approach to reduce biventricular filling pressures in HF. The VENUS-HF trial will test the safety and feasibility of SVC therapy in HF.

IVC filter removal after extended implantation periods

ObjectiveLife-threatening complications have been reported in patients with chronic retrievable IVC filters. National health agencies have urged hospitals to assess all patients with retrievable IVC filters for filter removal. The aim of the current study was to identify those patients with unretrieved chronic IVC filters, document complications and removal techniques. MethodsWe identified a cohort with unretrieved IVC filters inserted between January 2001 and December 2013. These patients were invited back to clinic for review with CT imaging to determine complications, if any, and offer removal. Data collected included demographics, complications and retrieval characteristics. Results289 patients were discovered to still have a filter in situ. Of these, 193 patients were verified as deceased. Eighty-nine patients were notified, with no current contact information available on the remaining seven. Thirty-six attended for review, 20 females, 16 males, with an average age of 63.5 years. Complications identified at CT were 2 occluded IVCs (5.8%), 4 fractured filters (11.7%) and filter penetration in all cases (37.5% grade 2, 56.25% grade 3). Sixteen patients agreed to proceed with filter removal, 10 declined the opportunity and 6 were unfit or had ongoing indication for the filter. Two are awaiting removal and two had IVC occlusion. Subsequent retrieval was successful in 93% of cases (14/15). The mean time to removal from implant was 3846.9 days (SD 980.3). Advanced techniques were utilized in 10 cases and there were no mortalities or morbidities. ConclusionRetrievable inferior vena cava filters are not benign and practitioners need to be aware of regulatory guidelines. Unretrieved filters can be successfully retrieved using standard and advanced methods with low morbidity and mortality.

2562 Duodenal Perforation From an Inferior Vena Cava Filter as a Rare Cause of Persistent Abdominal Pain

INTRODUCTION: Deep vein thrombosis (DVT) continues to be a significant source of morbidity for surgical patients. Inferior vena cava (IVC) filter placement is indicated for DVT in patients who have contraindications to anticoagulation or failure of anticoagulation. Over the last decade, there is exponential increase of IVC filter placement with increased complications reported. These include IVC penetration, IVC occlusion, insertion complication and filter migration. We report a rare case of symptomatic duodenal perforation by an IVC filter migration. CASE DESCRIPTION/METHODS: A 33-year-old female with a history of paraplegia secondary to motor vehicle accident, recurrent DVTs, and placement of IVC filter 10 years ago presented to the hospital for persistent epigastric pain for the past 5 years. Patient denied any nausea, vomiting, diarrhea, or hematochezia. Physical exam showed epigastric tenderness. Labs including complete blood count were unremarkable. CT scan showed a longstanding IVC occlusion with collaterals and displaced IVC filter into the duodenum and into the L3 vertebral body (Figure 1). An EGD confirmed prong migration to the second portion of the duodenum (Figure 2). This was distal to the ampulla and penetrating the duodenal wall with the tip embedding the opposite wall. Due to multiple workups being otherwise negative and symptomatic duodenal perforation of the IVC filter, she has been scheduled for an open IVC filter extraction with duodenal and caval repair. DISCUSSION: Duodenal and aortic perforations by IVC filters have been increasingly reported in the past 10 years although still rare. Penetration of the filter struts through the wall of the IVC can be asymptomatic. However symptomatic patients may present with epigastric pain, gastrointestinal bleeding and small bowel obstruction. Currently, there are no guidelines for the management of such patients. Most cases have been repaired using an open repair with excellent outcomes; however, endovascular retrieval and repair is being recognized as an alternative option especially in high risk patients. This case illustrates that even though IVC migration and perforation is a rare complication, it needs to be recognized as a potential cause for gastrointestinal symptoms in these patients. Retrievable IVC filters should always be removed if possible when deemed unnecessary to prevent complications such as migration from developing.

Application of multi-slice spiral CT in diagnosis of inferior vena cava lesions in Budd-Chiari syndrome and its clinical value

Objective To study the application of multiple row spiral CT (MSCT) in the diagnosis of inferior vena cava lesions in Budd Chiari syndrome (BCS) and its clinical value. Methods Eighty patients with BCS admitted to the Central Hospital of Shan County from May 2017 to May 2018 were divided into two groups by digital grouping method, with 40 cases in each group.The control group was diagnosed by ultrasound, and the study group was diagnosed by multi-slice CT.The pathological changes, tissue contrast of inferior vena cava and hepatic vein and the diagnostic sensitivity, specificity, positive predictive value and negative predictive value of inferior vena cava obstruction were compared between the two groups. Results The pathological diagnosis rate in the study group was significantly higher than that in the control group(χ2=4.562, 4.695, 4.125, 5.124, all P<0.05). The contrast of inferior vena cava and hepatic vein tissues in the study group was significantly higher than that in the control group (t=12.897, 13.214, all P<0.05). The sensitivity, specificity, positive predictive value and negative predictive value of the diagnosis of inferior vena cava occlusion in the study group were higher than those in the control group (the control group: 91.2%, 98.6%, 97.3%, 80.3%, the study group: 100.0%, 99.5%, 98.2%, 100.0%, χ2=11.897, 10.214, 11.235, 13.564, all P<0.05). Conclusion The application of MSCT in the diagnosis of BCS-inferior vena cava lesions, can display the lesions comprehensively and intuitive guidance in the treatment of inferior vena cava lesions, has high diagnostic value, it is worthy of popularization and application in clinic. Key words: Tomography, spiral computed; Budd-Chiari syndrome; Vena cava, inferior; Diagnosis; Ultrasonography; Sensitivity and specificity

Long-term survival after anterior approach right hepatectomy combined with inferior vena cava thrombectomy using trans-diaphragmatic intrapericardial inferior vena cava occlusion: a case report and review of the literature

BackgroundPresence of inferior vena cava tumor thrombosis (IVCTT) is an unfavorable factor to prognosis for patients with hepatocellular carcinoma (HCC).Case presentationHerein we report a case of HCC with IVC tumor thrombosis extending from the right hepatic vein (RHV) to the IVC, but it had not infiltrated the right atrium. Anterior approach right hepatectomy combined with IVC thrombectomy using trans-diaphragmatic IVC occlusion was performed for this patient. The patient is alive with disease-free at 32 months after treatment. A literature review was also performed. This case was demonstrated with the details and concepts of surgery.ConclusionThis case suggested that surgical resection of HCC involving the IVC, but still outside the right atrium (RA), could offer satisfactory surgical outcomes in selected patients.

Abstract 622: Load-Independent Systolic Dysfunction and Altered Z-Disc Protein Phosphorylation in Swine with Stretch-Induced Myocardial Stunning

Objective: We recently demonstrated that a transient rise in left ventricular (LV) preload leads to a reversible reduction in LV ejection fraction in the absence of ischemia (“stretch-induced stunning”). The present study was designed to determine whether this phenomenon is characterized by impaired load independent LV systolic function and alterations in sarcomeric protein phosphorylation. Methods: Swine (n=9) received a 1 hour infusion of phenylephrine (PE; 18 mg/hour iv) to transiently elevate LV end-diastolic pressure (EDP). Load independent systolic function was derived from LV pressure volume loops collected during inferior vena cava occlusion at baseline and 30 min after PE (Transonic SciSense). In a subset of animals (n=5), LV tissue was collected 1 hour after PE for TMT-labeled, LC-MS-based quantitative phosphoproteomics using Orbitrap. Results: PE elicited a rise in LV EDP (9±2 to 29±3 mmHg, p&lt;0.01), followed by a reduction in LV ejection fraction and LV dP/dt max 30 min later. At this time, load independent indices of LV systolic function tended to exhibit a reduced slope with a significant rightward shift of the volume-axis intercept (V 0 ), indicative of decreased contractility ( Table ). This was accompanied by altered phosphorylation of 16 sarcomeric Z disc proteins at 27 phosphosites, including increased phosphorylation of α actinin, α crystallin B chain, desmin, and myotilin. Conclusions: Stretch-induced stunning following transient preload elevation is characterized by load independent systolic dysfunction. Phosphoproteomics implicate alterations in Z disc protein phosphorylation as a mechanism underlying contractile dysfunction in this condition.

SAT-167 THE CASE OF A NOT SO ABSENT INFERIOR VENA CAVA

Background: Congenital absence of the inferior vena cava (IVC) is an extremely rare condition, which may be congenital or due to perinatal thrombosis, is associated with lower limb deep vein thrombosis risk, non-healing venous ulcers and the development of collateral venous drainage systems. We report a case of a congenitally absent IVC in a patient with renal failure and subsequent renal transplantation, with recurrent acute kidney injury (AKI) related to exercise, whom underwent successful IVC stenting with restoration of venous flow. Case: The patient was a 28-year-old female with a diagnosis of congenital absence of her IVC, with venous drainage of her lower limbs achieved by markedly dilated ascending lumbar veins which drained into an enlarged azygous vein. She had a history of chronic kidney disease with renal transplant at age 4, which failed after recurrent unexplained episodes of acute tubular necrosis (ATN). After her second transplant at age 26 she continued to have recurrent episodes of biopsy proven ATN, which were subsequently found to be related to exercise with creatinine levels of more than 300µmol/L from a baseline of 113µmol/L. Pelvic angiography demonstrated abrupt pinching of the enlarged right lumbar vein at the L4/L5 vertebrae with straight leg raise and subsequent flow of blood into the left lumbar vein. The dilated ascending lumbar veins in the retroperitoneum, which drain the renal transplant, course between the psoas muscle and the lumbar vertebral bodies. During exercise, it is hypothesised that there is venous hypertension in the kidney due to outflow obstruction from compression of the ascending lumbar veins (from psoas muscle compression) at the level of L4/L5. There is subsequent decreased venous return, leading to arterial hypotension, poor renal perfusion, and AKI. These episodes recovered with intravenous fluids and bed rest. Botox injections into the psoas muscles were minimally beneficial in reducing exercise related AKI and complicated by a rash. CT venogram identified suggestion of a chronically occluded IVC remnant, with contrast present in the native kidneys, which appeared small and unscarred, as well as a thin (2mm) cord extending from the liver to the transplant kidney (See Image 1). Subsequently, she underwent endovascular balloon recanalization of the right common iliac vein and IVC to 14mm with restoration of antegrade flow. Subsequent venogram demonstrated some elastic recoil and collapse of the recanalized IVC, so she underwent dilatation of the IVC to 18mm with iliocaval segment reconstruction with stents (20mm caval stents and 10mm iliac stents) shown in Image 2. Repeat imaging 2 days later demonstrated patent stenting in the common iliac vein and IVC, with persisting dilated azygous system, however the lumbar veins had decreased in calibre. Post stenting, her creatinine was 115µmol/L increasing to 144µmol/L after walking 20,000 steps/day for two consecutive days. Image 1: CT venogram showing chronically occluded IVC remnant (indicated with arrow). Image 2: Angiography showing successful IVC stent placement. ▪▪▪ ▪▪▪ The aim of iliocaval reconstruction was to provide a low resistance pathway for venous drainage which would not be subject to extrinsic compression. Iliocaval reconstruction appears to have improved the effect of exercise on renal function.

Interventional Treatment Strategy for Primary Budd-Chiari Syndrome with Both Inferior Vena Cava and Hepatic Vein Involvement: Patients from Two Centers in China.

This retrospective study evaluated interventional treatments (recanalization, balloon dilation, and/or stent placement) for Budd-Chiari syndrome (BCS), caused by combined obstruction of the inferior vena cava (IVC) and hepatic veins (HVs). Before and after interventional therapy, patients with BCS (n = 162; asymptomatic 105.2 ± 103.3mo; follow-up 15 [6-24] mo) underwent imaging studies (color Doppler ultrasound, CT, or MRI), and inferior vena cavography and manometry. Venous lesions were characterized by occlusion features, and presence of thrombosis and peripheral collateral vessels. One, 2, and 3 main HV occlusions were observed, respectively, in 25 (15.4%), 61 (37.7%), and 76 (46.9%) patients. Eighty-three (51.2%), 98 (60.5%), and 104 (64.2%) patients had, respectively, large accessory HVs, venous collaterals formed between the HVs, or venous communicating branches between the HV and the peritoneal veins. The middle, left, and right HV was patent in 32 (19.8%), 35 (21.6%), and 44 (27.2%) patients. Recanalization of both hepatic and caval occlusions was successful in 96% (51/53) of those attempted; recanalization of IVC occlusion was successful in 97% (106/109). Among 157 patients successfully treated, 146 were cured and 11 showed clinical improvement. Clinical symptoms were relieved in 82.4% after the initial intervention, and 94.2% after the second intervention. Recanalization and balloon angioplasty was effective for the management of BCS with concurrent HV and IVC occlusions. The majority of patients required only IVC recanalization. The outcome of patients treated only by IVC intervention was similar to that of patients given combined HV and IVC intervention.