Impact of Breathing Control Training Program on sonographic quantification of abdominal vasculature.

OBJECTIVES: To compare vascular scanning parameters (vessel diameter, peak systolic velocity, end-diastolic velocity, and resistive index) and scanning time before and after breathing control training program for selected abdominal vessels. METHODS: This study was pre and post quasi-experimental. The researchers designed a breathing training program that gives participants instructions through a video describing breathing maneuvers. Data were collected at the ultrasound laboratory/College of Health and Rehabilitation Sciences in Princess Nourah bint Abdul Rahman University, Riyadh, Saudi Arabia from January 2023 to November 2023. About 49 volunteers at the university participated in the study. Scanning was performed two times for the right renal artery, upper abdominal aorta, inferior vena cava, and superior mesenteric artery. Scanning time was measured before and after the program as well. A paired sample t-test was used to compare the parameters means and time before and after the program. RESULTS: The program had a significant effect on the following parameters: right renal artery peak systolic velocity (p=0.042), upper abdominal aortic peak systolic velocity, and resistive index (p=0.014, p=0.014 respectively), superior mesenteric artery and inferior vena cava diameters (p=0.010 and p=0.020). The scanning time was reduced significantly (p<0.001). CONCLUSION: The breathing training program saves time and improves ultrasound measurement quality. Hospitals and health centers should consider the importance of breathing control training programs before abdominal scanning.

Monitoring the venous circulation: novel techniques and applications.

PURPOSE OF REVIEW: Venous pressure is an often-unrecognized cause of patient morbidity. However, bedside assessment of PV is challenging. We review the clinical significance of venous pressure measurement, existing techniques, and introduce the Venous Excess Ultrasound (VExUS) Score as a novel approach using doppler ultrasound to assess venous pressure. RECENT FINDINGS: Studies show clear associations between elevated venous pressure and adverse outcomes in critically ill patients. Current venous pressure measurement techniques include physical examination, right heart catheterization (RHC), two-dimensional ultrasound, and a variety of labor-intensive research-focused physiological maneuvers. Each of these techniques have specific shortcomings, limiting their clinical utility. To address these gaps, Beaubien-Souligny et al. introduced the VExUS Score, a novel doppler ultrasound-based method that integrates IVC diameter with doppler measurements of the hepatic, portal, and renal veins to generate a venous congestion assesment. Studies show strong correlations between VExUS score and RHC measurements, and well as an association between VExUS score and improvement in cardiorenal acute kidney injury, diuretic response, and fluid status shifts. However, studies in noncardiac populations have been small, heterogenous, and inconclusive. SUMMARY: Early studies evaluating the use of doppler ultrasound to assess venous congestion show promise, but further research is needed in diverse patient populations and clinical settings.

Quantifying Inferior Vena Cava Compliance and Distensibility in an In Vivo Ovine Model Using 3D Angiography.

Synthetic vascular grafts overcome some challenges of allografts, autografts, and xenografts but are often more rigid and less compliant than the native vessel into which they are implanted. Compliance matching with the native vessel is emerging as a key property for graft success. The current gold standard for assessing vessel compliance involves the vessel's excision and ex vivo biaxial mechanical testing. We developed an in vivo method to assess venous compliance and distensibility that better reflects natural physiology and takes into consideration the impact of a pressure change caused by flowing blood and by any morphologic changes present. This method is designed as a survival procedure, facilitating longitudinal studies while potentially reducing the need for animal use. Our method involves injecting a 20 mL/kg saline bolus into the venous vasculature, followed by the acquisition of pre and post bolus 3D angiograms to observe alterations induced by the bolus, concurrently with intravascular pressure measurements in target regions. We are then able to measure the circumference and the cross-sectional area of the vessel pre and post bolus. With these data and the intravascular pressure, we are able to calculate the compliance and distensibility with specific equations. This method was used to compare the inferior vena cava's compliance and distensibility in native unoperated sheep to the conduit of sheep implanted with a long-term expanded polytetrafluorethylene (PTFE) graft. The native vessel was found to be more compliant and distensible than the PTFE graft at all measured locations. We conclude that this method safely provides in vivo measurements of vein compliance and distensibility.

Modeling of multiple atrial septal defects with inferior vena cava rim deficiency: Three-dimensional visualization of the rim based on transthoracic echocardiographic imaging.

The morphologic features of the multiple atrial septal defects assessed by TTE-based 3D imaging were similar to those by 3D-TEE. TTE-based 3D model had excellent visibility, allowing observation of 3D structure of the rims of the defects. It may be useful method for assessment of the multiple atrial septal defects.

Impact of Age-Related Change in Caval Flow Ratio on Hepatic Flow Distribution in the Fontan Circulation.

BACKGROUND: The Fontan operation is a palliative technique for patients born with single ventricle heart disease. The superior vena cava (SVC), inferior vena cava (IVC), and hepatic veins are connected to the pulmonary arteries in a total cavopulmonary connection by an extracardiac conduit or a lateral tunnel connection. A balanced hepatic flow distribution (HFD) to both lungs is essential to prevent pulmonary arteriovenous malformations and cyanosis. HFD is highly dependent on the local hemodynamics. The effect of age-related changes in caval inflows on HFD was evaluated using cardiac magnetic resonance data and patient-specific computational fluid dynamics modeling. METHODS: SVC and IVC flow from 414 patients with Fontan were collected to establish a relationship between SVC:IVC flow ratio and age. Computational fluid dynamics modeling was performed in 60 (30 extracardiac and 30 lateral tunnel) patient models to quantify the HFD that corresponded to patient ages of 3, 8, and 15 years, respectively. RESULTS: SVC:IVC flow ratio inverted at ≈8 years of age, indicating a clear shift to lower body flow predominance. Our data showed that variation of HFD in response to age-related changes in caval inflows (SVC:IVC, 2, 1, and 0.5 corresponded to ages, 3, 8, and 15+, respectively) was not significant for extracardiac but statistically significant for lateral tunnel cohorts. For all 3 caval inflow ratios, a positive correlation existed between the IVC flow distribution to both the lungs and the HFD. However, as the SVC:IVC ratio changed from 2 to 0.5 (age, 3-15+) years, the correlation's strength decreased from 0.87 to 0.64, due to potential flow perturbation as IVC flow momentum increased. CONCLUSIONS: Our analysis provided quantitative insights into the impact of the changing caval inflows on Fontan's long-term HFD, highlighting the importance of SVC:IVC variations over time on Fontan's long-term hemodynamics. These findings broaden our understanding of Fontan hemodynamics and patient outcomes.

Unusual origins of cardiac insufficiency: a case of iliac arteriovenous fistula post-spinal disc surgery.

In this case report, we present the unique and intriguing case of a 57-year-old man who experienced exertional palpitations and shortness of breath for 5 years. He was diagnosed with idiopathic heart failure three years ago, leading to diuretic treatment. Physical examination revealed notable left lower extremity swelling, severe varicose veins, and cardiac murmurs. Echocardiography showed significant cardiac enlargement and severe functional mitral and tricuspid valve regurgitation. Computed tomography (CT) imaging uncovered a 10 mm left common iliac arteriovenous fistula, causing abnormal early filling of the inferior vena cava (IVC) and marked IVC dilation. Open surgical repair of the arteriovenous fistula resulted in symptom relief and improved cardiac function. This case underscores the importance of considering unusual causes in heart failure patients and highlights the value of early diagnosis and intervention in complex cardiac-vascular interactions.

Resection of primary left renal vein leiomyosarcoma with renal preservation following an unusual clinical presentation.

An elderly man was referred to vascular surgery on incidental discovery of a left retroperitoneal mass ultimately found to be of left renal vein (LRV) origin. He initially presented with recurring lower back pain. CT of the abdomen/pelvis showed a 6.0×5.5 cm lobulated retroperitoneal mass anterior to the infrarenal aorta. Resection of the mass necessitated a multidisciplinary team consisting of medical oncologists, radiation oncologists, urologists and vascular surgeons. In efforts to obtain an R0 margin, en-bloc resection of the LRV from its confluence with the inferior vena cava (IVC) was necessary. A primary repair of the IVC was performed with preservation of the left kidney. The patient's back pain has since resolved after the surgery. A literature search found IVC reconstructions to be safe and effective in the removal of vascular leiomyosarcomas.

Retrieval of an inferior vena cava Greenfield filter 34 years after insertion.

Inferior vena cava (IVC) filters are engineered medical devices deployed in the IVC primarily to prevent a pulmonary embolism from occurring. In this article, we present a case of an IVC filter that was successfully retrieved from a patient after being in place for 34 years. The patient presented to hospital for trauma in which subsequent imaging showed tines of an IVC filter protruding outside of the vessel with one of the tines penetrating the duodenal wall. The filter was successfully removed with no complications. This report adds to the existing literature by yielding an example of an adverse risk that can be associated with the placement of IVC filters. In addition, to the authors' best knowledge, this is the longest reported length of time that an IVC filter has stayed in a patient before being removed, thus adding another intriguing detail to the case.

Retroperitoneal venous malformation mimics paraganglioma on triple imaging modalities.

Here, we report a case of a woman in her 50s who was referred for an incidentally discovered lesion anterior to the origin of inferior vena cava suspicious for a paraganglioma following a CT scan for vaginal bleeding. A follow-up 68Ga-DOTATATE PET-CT and MRI of the abdomen reinforced the radiological impression of an extra-adrenal paraganglioma (EAP). The EAP was deemed non-functional given normal urine biogenic amine, supine plasma fractionated metanephrines and chromogranin A levels. The mass was resected laparoscopically without perioperative blockade. Histological examination revealed a venous malformation. Extrahepatic abdominal venous malformations are rare and can be indistinguishable from an EAP on imaging preoperatively. Although benign, the lesion nevertheless warrants excision as it is associated with a risk of haemorrhage.

Impact of 4D-Flow CMR Parameters on Functional Evaluation of Fontan Circulation.

We sought to evaluate the potential clinical role of 4D-flow cardiac magnetic resonance (CMR)-derived energetics and flow parameters in a cohort of patients' post-Fontan palliation. In patients with Fontan circulation who underwent 4D-Flow CMR, streamlines distribution was evaluated, as well a 4D-flow CMR-derived energetics parameters as kinetic energy (KE) and energy loss (EL) normalized by volume. EL/KE index as a marker of flow efficiency was also calculated. Cardiopulmonary exercise test (CPET) was also performed in a subgroup of patients. The population study included 55 patients (mean age 22 ± 11 years). The analysis of the streamlines revealed a preferential distribution of the right superior vena cava flow for the right pulmonary artery (62.5 ± 35.4%) and a mild preferential flow for the left pulmonary artery (52.3 ± 40.6%) of the inferior vena cave-pulmonary arteries (IVC-PA) conduit. Patients with heart failure (HF) presented lower IVC/PA-conduit flow (0.75 ± 0.5 vs 1.3 ± 0.5 l/min/m2, p = 0.004) and a higher mean flow-jet angle of the IVC-PA conduit (39.2 ± 22.8 vs 15.2 ± 8.9, p < 0.001) than the remaining patients. EL/KE index correlates inversely with VO2/kg/min: R: - 0.45, p = 0.01 peak, minute ventilation (VE) R: - 0.466, p < 0.01, maximal voluntary ventilation: R:0.44, p = 0.001 and positively with the physiological dead space to the tidal volume ratio (VD/VT) peak: R: 0.58, p < 0.01. From our data, lower blood flow in IVC/PA conduit and eccentric flow was associated with HF whereas higher EL/KE index was associated with reduced functional capacity and impaired lung function. Larger studies are needed to confirm our results and to further improve the prognostic role of the 4D-Flow CMR in this challenging population.

Renal cell carcinoma with an "uncoiling" tumor thrombus: intraoperative shift from level III to level IV.

BACKGROUND: The gold standard treatment for renal cell carcinoma (RCC) with tumor thrombus (TT) is complete surgical excision. The surgery is complex and challenging to the surgeon, especially with large tumor thrombus extending into the inferior vena cava (IVC) and right atrium. Traditionally, these difficult cases required the use of cardiopulmonary bypass (CPB) with or without deep hypothermic cardiac arrest, but in recent years, different surgical techniques derived from the field of liver transplantation have been used in efforts to avoid CPB. CASE PRESENTATION: We present a case of RCC with TT level IIIc (extending above major hepatic veins) that "uncoiled" intraoperatively into the right atrium after division of the IVC ligament, transforming into a level IV TT. Despite the new TT extension, the surgery was successfully completed exclusively through an abdominal approach without CPB and while using intraoperative transesophageal echocardiography (TEE) monitoring and a cardiothoracic team standby. CONCLUSIONS: This case highlights the need for a multidisciplinary approach and the utility of intraoperative continous TEE monitoring which helped to visualize the change of the TT venous extension, allowing the surgical teamto modify their surgical approach as needed avoiding a catastrophic event.

A 42-year-old patient with renal cell carcinoma presenting as low back pain: A case report.

RATIONALE: Renal cell carcinoma (RCC) is the most common renal neoplasm, accounting for 2.4% of all cancers in Korea. Although the usual clinical manifestations of RCC include flank pain, hematuria, and palpable mass, RCC is generally characterized by a lack of early warning signs and is mostly discovered incidentally in advanced stage. This case report describes a 42-year-old Korean man diagnosed with giant RCC who presented with simple back pain. PATIENT CONCERNS: The clinical manifestation of a 42-year-old Korean man was chronic back pain. DIAGNOSES: Contrast-enhanced computed tomography showed a 19.1-cm sized heterogeneous enhancing mass on the right kidney and tumor thrombosis extending into inferior vena cava. INTERVENTION: Due to the large size of the tumor and extensive tumor thrombosis, the multidisciplinary team decided to administer neoadjuvant chemotherapy and an anticoagulant. Following 12 cycles of treatment with nivolumab and cabozantinib, he underwent a right radical nephrectomy with an adrenalectomy and tumor thrombectomy. OUTCOMES: Treatment was successful and posttreatment he started a cancer rehabilitation program. He was followed-up as an outpatient and no longer complains of back pain. LESSONS: RCC can manifest clinically as back pain, with diagnosis being difficult without appropriate imaging modalities. RCC should be included in the differential diagnosis of patients with low back pain, even at a young age.

Increased inferior vena cava wall thickness as a sign of extensive venous inflammation in Behçet's Disease.

INTRODUCTION/OBJECTIVES: Behçet's disease (BD) affects both arterial and venous vessels. We have previously shown that common femoral vein wall thickness (WT) is increased in BD and can be used as a diagnostic test. However, there is limited data assessing large veins. Therefore, this study seeks to assess inferior vena cava wall thickness (IVC) by transthoracic echocardiography (TTE) in BD compared to healthy controls (HC). METHODS: Age- and gender-matched 70 BD patients and 51 HC were included. IVC wall thickness and common femoral vein WT were measured by TTE and Doppler ultrasonography, respectively. All examinations were performed on the same day as the clinical assessment. RESULTS: The mean IVC wall thickness of BD patients was significantly higher than HC (2.9 mm (0.3) vs 2.6 mm (0.3), p < 0.001). Patients with mucocutaneous involvement (2.8 mm (0.3)) and major organ involvement (2.9 mm (0.3)) had significantly thicker walls compared to HC (p = 0.003, p < 0.001, respectively). IVC wall thickness was higher in patients with vascular involvement compared to those with nonvascular major organ involvement (3.1 mm (0.3) vs 2.8 mm (0.2), p = 0.04). There was a moderate correlation between IVC and common femoral vein WT (r = 0.49 for the right, r = 0.43 for the left, p = 0.01 for both). CONCLUSION: This study shows that venous wall inflammation is not limited to lower extremity veins and is also present in IVC walls of BD patients regardless of IVC involvement. Vascular wall inflammation is probably a widespread vascular event of all venous walls in BD. Key Points • Venous wall inflammation is not limited to lower extremity veins and is present also in IVC wall in Behçet's disease. • Extensive venous wall inflammation in Behçet's disease includes large venous structures despite not being clinically involved.

Percutaneous image-guided management of a misplaced pericardiocentesis catheter into the inferior vena cava.

Misplacement of pericardiocentesis catheter in central veins is a rare complication that can be managed with several methods. In this case, we report a percutaneous image-guided plug-assisted management of a misplaced pericardiocentesis catheter into the inferior vena cava through a transhepatic tract successfully occluded. This minimally invasive technique was not previously described in this setting and had a favorable long-term outcome.

Clinical case of a minimally invasive technique guided by imaging to fix a complication of a misplaced drainage catheter for pericardial hemorrhageThis clinical case reports how to manage, using a minimally invasive technique guided by imaging, an accidental puncture of the liver and the inferior vena cava during a pericardial hemorrhage drainage. The outcome was good, with technical success and a favorable outcome for the patient.

Use of inferior vena cava guided fluid therapy in the treatment of septic shock: A randomised controlled trial.

INTRODUCTION: By administering inferior vena cava (IVC) directed fluid, it is possible to avoid the use of additional fluid and fluid overload in patients with septic shock (SS) and sepsis-induced hypoperfusion (SIH). METHODOLOGY: In patients with SIH and SS, we conducted prospective observational research on fluid therapy. A time-motion trace of the IVC diameter was created using M-mode imaging. The ability to predict fluid responsiveness was based on the IVC collapsibility index (cIVC) > 40%. Participants were randomised into 2 groups using a permuted block-of-four randomization list, with the investigators being blinded prior to patient allocation. They were split equally between the usual-care (UC) group, which received sepsis-guided fluid treatment, and the interventional ultrasound-guided fluid therapy (UGFT) group. RESULTS: The average age of the participants was 63.2 years (62.8 years for the UGFT group and 63.7 years for the UC group). Co-morbid health conditions were practically the same in both arms at baseline. Prior to enrolment, both groups received the same quantity of fluid as part of resuscitation (UGFT arm received 2.4 0.6 L, UC group received 2.2 0.7 L). The UGFT group outperformed the UC group with a P value of 0.02 due to a significantly lower positive fluid balance after 72 hours of ICU discharge (-1.37 L), which rendered the UGFT group superior to the UC group. Even after accounting for the fluids consumed before enrolment, there was still a sizable difference in the fluids infused. When the pre-enrolment fluids were counted at 72 hours, UGFT participants still displayed a decreased positive fluid balance. However, there was no discernible difference in the 30-day mortality rate overall (6.3% difference, UGFT: 15.7%, and UC: 22.0%). CONCLUSIONS: In contrast to the UC group, the UGFT arm of our study demonstrated a statistically significant benefit of Point of Care USG (POCUS) guided fluid therapy during resuscitation in sepsis in reducing the positive fluid balance in 72 hours, preventing fluid overload, and reducing the need for dialysis and invasive ventilation. However, there was no statistically significant variation in the 30-day mortality rate.

Inferior Vena Cava Filter Long Term Complications and Retrieval Techniques: A Case Series and Literature Review.

INTRODUCTION AND IMPORTANCE: Long-term mechanical complications after inferior vena cava (IVC) filter placement include embedded or tilted filters, erosion of the vena cava, filter thrombosis. In the setting of caval thrombosis, patients may subsequently develop venous hypertension and post-thrombotic syndrome (PTS). Here we present three unique cases of IVC filter complications and surgical management. CASE PRESENTATION: A 30-year-old female presented with acute abdominal pain, revealing a duodenal perforation caused by an IVC filter eroding into her duodenum. A 42-year-old female with an IVC filter in place for 20 years due to a prior pulmonary embolism underwent laser-assisted retrieval of the filter due to concerns of caval adherence. A 48-year-old male with a history of DVT, venous stasis ulcer, and an IVC filter presented for filter retrieval. CLINICAL FINDINGS AND INVESTIGATIONS: The surgical techniques described in this report include complicated IVC filter retrieval, performed in cases of filter complications including migration, fracture, duodenal perforation and IVC thrombosis resulting in PTS. One case, requiring open retrieval, is explained and the surgical technique is provided. There are images and videos of these procedures to enrich the learning experience. INTERVENTION AND OUTCOMES: The surgical techniques described in this report include complicated inferior vena cava filter retrieval, performed in cases of filter complications including migration, fracture, duodenal perforation and IVC thrombosis. One case, requiring open retrieval, is explained and the surgical technique is provided. There are images and videos of these procedures to enrich the learning experience. RELEVANCE AND IMPACT: Endovascular retrieval of long-term complicated IVC filters is challenging, but it can be a safely performed in many patients. However, open surgery may be necessary in selected patients.