Mesoportal bypass, interposition graft, and mesocaval shunt: Surgical strategies to overcome superior mesenteric vein involvement in pancreatic cancer.

BACKGROUND: In pancreatic cancer, extensive tumor involvement of the mesenteric venous system poses formidable challenges to operative resection. Such involvement can result from cavernous collateral veins leading to increased intraoperative blood loss or long-segment vascular defects of not only just the superior mesenteric vein but also even jejunal/ileal branches. Strategies to facilitate margin-free resection and safe vascular reconstruction in pancreatic surgery are important, particularly because systemic control of the tumor is improving with multi-agent chemotherapy regimens. METHODS: We describe a systematic, multidisciplinary assessment for patients with pancreatic cancer that involves the superior mesenteric vein, as well as the preoperative planning of those undergoing operative resection. In addition, detailed descriptions of operative approaches and technical strategies, which evolved with increasing experience at a high-volume center, are presented. RESULTS: For the preoperative evaluation of tumor-free, vascular locations for potential reconstruction and collateralization, computed tomographic imaging with high-resolution of vascular structures (used with 3-dimensional or cinematic rendering) allows a precise calibration of radiographic data with intraoperative findings. From an operative perspective, we identified 5 potential strategies to consider for resection: collateral preservation, mesoportal bypass (preresection), mesoportal interposition graft (postresection), mesocaval shunt, and various combinations of these strategies. Many of these techniques use interposition grafts, making it essential to assess autologous veins (preferred conduit for reconstruction) or to prepare cryopreserved vascular allografts (an alternative conduit, which must be thawed and should be matched for size and blood type). CONCLUSION: Herein we share operative strategies to overcome involvement of the superior mesenteric vein in pancreatic cancer. Improvements in preoperative planning and operative technique can address common barriers to resection with curative intent.

The coronary sinus interatrial connection with total unroofing coronary sinus discovered late after correction of secundum atrial septal defect.

A coronary sinus (CS) interatrial connection is a rare congenital anomaly which can be in various types from atrial septal defect type unroofing CS to the total absence of the CS. The pathology usually accompanies the left superior caval vein (LSCV) draining to CS and in case of its absence directly to the left atrium (LA). We present a 53-year-old woman after surgical correction of a secundum atrial septal defect in 1974, with a CS interatrial connection and paroxysmal atrial fibrillation (PAF). She gave a history of PAF and was admitted to our clinic due to progressive exertional intolerance, peripheral edema, and mild hypoxia (SatO2 92%) with subsequent cyanosis. Transthoracic echocardiography showed a left-to-right shunt in the posteroinferior part of the atrial septum. Computed tomography revealed a persistent LSCV draining directly into the LA, the absence of the CS, and cardiac veins draining into the LA. The right atrium (RA) and the LA were connected via a tunnel with a visible contrast passage from the left to the right side-the persisting mouth of the coronary sinus. The patient was qualified for surgical correction. A glutaraldehyde-treated autologous pericardial patch was used to construct the tunnel connecting the LSVC and the RA. The second part of the patch was used to close the atrial communication at the inferior vena cava level. The patient had an uncomplicated postoperative course and is now classified in New York Heart Association Class II.

Efficacy of bubble contrast echocardiography in detecting pulmonary arteriovenous fistulas in children with univentricular heart after total cavopulmonary connection.

BACKGROUND: Development of pulmonary arteriovenous fistulas in patients with cavopulmonary anastomosis may result in a significant morbidity. Although the use of bubble contrast echocardiography with selective injection into both the branch pulmonary arteries in identifying pulmonary arteriovenous fistulas has been increasing, the actual efficacy of this diagnostic modality has not been properly evaluated. Thus, this study aimed to assess the efficacy of bubble contrast echocardiography in detecting pulmonary arteriovenous fistulas in children with total cavopulmonary connection. METHODS: A total of 140 patients were included. All patients underwent cardiac catheterisation. Bubble contrast echocardiographic studies were performed by injecting agitated saline solution into the branch pulmonary arteries. Transthoracic echocardiograms that use an apical view were conducted to assess the appearance of bubble contrast in the systemic ventricles. Then, the contrast echocardiogram results and other cardiac parameters were compared. RESULTS: No correlation was found between contrast echocardiogram grade and other cardiac parameters, such as pulmonary capillary wedge saturation and pulmonary artery resistance. Moreover, only 13 patients had negative results on both the right and left contrast echocardiograms, and 127 of the 140 patients had positive results on contrast echocardiograms even though they had normal pulmonary capillary wedge saturation. Results showed that bubble contrast echocardiography was a highly sensitive method and was likely to obtain false-positive results. CONCLUSIONS: Bubble contrast echocardiography might be highly false positive in detecting pulmonary arteriovenous fistulas in patients with cavopulmonary anastomosis. We have to consider how we make use of this method. Further standardisation of techniques is required.

Is there any role for computed tomography imaging in anticipating the functional status in adults late after total cavopulmonary connection? A retrospective evaluation.

BACKGROUND: The Fontan procedure is performed in patients with congenital heart diseases and abnormal anatomy of the heart, which preclude intracardiac repair involving a separation of the systemic and pulmonary circulations. The role of computed tomography (CT) in assessing patients' clinical status after the total cavopulmonary connection (TCPC) procedure is not well defined. AIMS: To determine a potential role and diagnostic capability of CT in the functional assessment of adults with the TCPC. METHODS: Data obtained from 18 patients (10 women; mean [SD] age, 27.9 [6.3] years) with the TCPC were analyzed retrospectively. All patients underwent biochemical evaluation, cardiopulmonary exercise test, transthoracic echocardiography, and CT. Upon CT examination, the dimensions of the left and right pulmonary arteries, superior and inferior venae cavae, all pulmonary veins, and extracardiac conduits were measured. The measurements acquired by CT were correlated with the results of transthoracic echocardiography, cardiopulmonary exercise test, and biochemical analysis. RESULTS: The mean (SD) time after the TCPC was 18.5 (6.5) years. The area and circumference of the inferior vena cava significantly correlated with age (r = 0.503, P <0.05). A significant positive correlation was found between the area and circumference of a conduit and the predicted maximal oxygen uptake (r = 0.664, P <0.01). The area (ß = 0.746, R2 = 0.556, P <0.01) and the circumference (ß = 0.757, R2 = 0.572, P <0.01) of a conduit were considered significant predictors in estimating the value of maximal oxygen uptake. CONCLUSIONS: Our study showed an association between the dimensions of an extracardiac conduit and patient functional status, time elapsed since the procedure, and age of adults who underwent the TCPC in childhood. These findings support a more extensive use of CT in patients with TCPC, complemented by the measurements of the superior and inferior venae cavae and the conduit.

Dedicated Closure Device for Transcaval Access Closure: From Concept to First-in-Human Testing.

OBJECTIVES: This study sought to test safety and exploratory effectiveness of a dedicated transcaval closure device (TCD). BACKGROUND: Transcaval access enables delivery of large-caliber devices to the aorta in patients ineligible for transfemoral arterial access. Closure of aortocaval fistulae using off-label nitinol cardiac occluders has been shown to be safe, but persistent aortocaval fistulae at exit from the catheterization lab and bleeding complications were common in a prospective study. METHODS: Preclinical testing of the TCD was performed in 24 Yorkshire swine, including 10 under good laboratory practice conditions. Subsequently, subjects undergoing transcatheter aortic valve replacement for symptomatic severe aortic stenosis, ineligible for transfemoral arterial access, were enrolled in a U.S. Food and Drug Administration-approved early feasibility study of the TCD (Transmural Systems, Andover, Massachusetts). Independently adjudicated endpoints included technical, device, and procedural success, incorporating in-hospital and 30-day clinical and imaging follow-up. RESULTS: Transcaval access and closure in swine confirmed that at 30 days, TCDs were almost entirely endothelialized. Subsequently, 12 subjects were enrolled in the early feasibility study. Transcaval access, transcatheter aortic valve replacement, and aortocaval fistula closure was successful in all 12 subjects. The primary endpoint of technical success was met in 100% of subjects. Complete closure of the transcaval access tract was achieved in 75% of subjects at exit from the catheterization lab and in 100% of subjects at 30 days. There were zero modified Valve Academic Research Consortium-2 major vascular complications and zero Valve Academic Research Consortium-2 life-threatening or major bleeding complications related to transcaval access or the TCD. CONCLUSIONS: The TCD achieved complete closure of the transcaval access tract in most subjects at exit from the catheterization lab and essentially eliminated transcaval-related bleeding. Dedicated devices for transcaval access and closure could enable more widespread adoption of transcaval techniques without fear of bleeding complications. (Transmural Systems Transcaval Closure Device for Transcaval Access Ports During Transcatheter Aortic Valve Replacement; NCT03432494).

Reproducibility and Changes in Vena Caval Blood Flow by Using 4D Flow MRI in Pulmonary Emphysema and Chronic Obstructive Pulmonary Disease (COPD): The Multi-Ethnic Study of Atherosclerosis (MESA) COPD Substudy.

BackgroundChronic obstructive pulmonary disease (COPD) is associated with hemodynamic changes in the pulmonary vasculature. However, cardiac effects are not fully understood and vary by phenotype of chronic lower respiratory disease.PurposeTo use four-dimensional (4D) flow MRI for comprehensive assessment of the right-sided cardiovascular system, assess its interrater and intraobserver reproducibility, and examine associations with venous return to the right heart in individuals with chronic COPD and emphysema.Materials and MethodsThe Multi-Ethnic Study of Atherosclerosis COPD substudy prospectively recruited participants who smoked and who had COPD and nested control participants from population-based samples. Electrocardiography and respiratory gated 4D flow 1.5-T MRI was performed at three sites with full volumetric coverage of the thoracic vessels in 2014-2017 with postbronchodilator spirometry and inspiratory chest CT to quantify percent emphysema. Net flow, peak velocity, retrograde flow, and retrograde fraction were measured on 14 analysis planes. Interrater reproducibility was assessed by two independent observers, and the principle of conservation of mass was employed to evaluate the internal consistency of flow measures. Partial correlation coefficients were adjusted for age, sex, race/ethnicity, height, weight, and smoking status.ResultsAmong 70 participants (29 participants with COPD [mean age, 73.5 years ± 8.1 {standard deviation}; 20 men] and 41 control participants [mean age, 71.0 years ± 6.1; 22 men]), the interrater reproducibility of the 4D flow MRI measures was good to excellent (intraclass correlation coefficient range, 0.73-0.98), as was the internal consistency. There were no statistically significant differences in venous flow parameters according to COPD severity (P > .05). Greater percent emphysema at CT was associated with greater regurgitant flow in the superior and inferior caval veins and tricuspid valve (adjusted r = 0.28-0.55; all P < .01), particularly in the superior vena cava.ConclusionFour-dimensional flow MRI had good-to-excellent observer variability and flow consistency. Percent emphysema at CT was associated with statistically significant differences in retrograde flow, greatest in the superior vena cava.© RSNA, 2019Online supplemental material is available for this article.See also the editorial by Choe in this issue.

Anatomical anomalies and variations of main thoracic vessels in dogs: a computed tomography study.

INTRODUCTION: There is scarce information about the prevalence of anomalies and anatomical variations of the main great thoracic vessels in dogs, particularly in dogs without congenital heart disease. ANIMALS: The study included 878 privately owned dogs. MATERIAL AND METHODS: Computerized tomography (CT) thoracic studies carried out between 2011 and 2014 for a variety of reasons were reviewed. The prevalence of anomalies and anatomical variations of the aorta and vena cava, the arterial branches of the aortic arch and the main branches of the intrathoracic veins in dogs with no evidence of congenital heart disease was evaluated. Poor-quality CTs, CTs with thoracic pathology that impaired visualization or those of young dogs with clinical evidence or suspicion of congenital cardiac disease were excluded. RESULTS: Eight hundred two CT studies were analysed. Eight dogs (1%) showed an anatomic anomaly. The most common anomaly was an aberrant retroesophageal right subclavian artery (n = 7, 0.8%). One dog showed a dilated azygos vein secondary to an interrupted vena cava. Three types of branching of the common carotid arteries were observed: both arteries arising at the same point (type I: n = 506/742; 68.2%), separated (type II: n = 212/742; 28.6%) or from a common trunk (type III: n = 24/742; 3.2%). CONCLUSIONS: Major anatomical variations or anomalies of the main great thoracic vessels in dogs without congenital cardiac disease were rare. An aberrant retroesophageal right subclavian artery was the most common anomaly found. Three slight variations of common carotid artery branching were identified. These findings might be of relevance for surgical or catheterization procedures.

Excimer laser assisted complex inferior vena cava filter retrieval: a single institution's experience over 6 years.

AIM: To investigate inferior vena cava (IVC) filter retrievals and the use of the excimer laser sheath to assist in complex cases. MATERIALS AND METHODS: Retrospective analysis was undertaken of 181 attempted filter retrievals over a 6 year period. Pre- and perioperative imaging was analysed from both standard retrieval and complex retrieval techniques. RESULTS: One hundred and eighty-one IVC filter retrievals were attempted: 130 (72%) standard retrievals were successful and 51 (28%) failed due to device endothelialisation. Forty (23%) cases then had subsequent successful complex retrieval under general anaesthetic. Eighteen (45%) cases were removed with the sling technique and 22 (55%) cases using the excimer laser dissection technique. Where preoperative venography/computed tomography (CT) demonstrated embedding of the filter feet versus filter apex, this was predictive of requiring dissection techniques versus sling technique (13/18 patients; p<0.05 chi-squared test). The difference in device indwelling time was statistically significant between the successful standard retrieval group (134 days) versus patients who failed standard retrieval and required complex techniques (243 days; p=0.00018). CONCLUSION: Standard retrieval techniques failed in 28% of cases. This correlated with devices that were indwelling for longer. When imaging demonstrated filter-feet endothelisation/perforation, this was predictive of requiring dissection techniques with the excimer laser.

Intra-caval Percutaneous Radiofrequency Ablation for a Neuroendocrine Tumor (NET) Metastasis in Transplanted Liver.

Less than 1% of patients with liver metastases from neuroendocrine tumors (NETs) are susceptible to liver transplantation. We report a case of a patient transplanted 13 years ago for NET metastases, with a lesion histologically proved for NET metastasis located at the cava vein anastomosis. He was treated with percutaneous radiofrequency ablation (RFA) after a first failed attempt of endovascular approach. The vascular heat sink, which RFA is susceptible to, was considered an advantage in this case, since it restricted the propagation of heat only to the tissue located in the very proximity of the RFA antenna, protecting the inferior vena cava vessel walls. This positive result may suggest an additional use of RFA in selected challenging cases.

Denali, Tulip, and Option Inferior Vena Cava Filter Retrieval: A Single Center Experience.

PURPOSE: To compare the technical success of filter retrieval in Denali, Tulip, and Option inferior vena cava filters. MATERIALS AND METHODS: A retrospective analysis of Denali, Gunther Tulip, and Option IVC filters was conducted. Retrieval failure rates, fluoroscopy time, sedation time, use of advanced retrieval techniques, and filter-related complications that led to retrieval failure were recorded. RESULTS: There were 107 Denali, 43 Option, and 39 Tulip filters deployed and removed with average dwell times of 93.5, 86.0, and 131 days, respectively. Retrieval failure rates were 0.9% for Denali, 11.6% for Option, and 5.1% for Tulip filters (Denali vs. Option p = 0.018; Denali vs. Tulip p = 0.159; Tulip vs. Option p = 0.045). Median fluoroscopy time for filter retrieval was 3.2 min for the Denali filter, 6.75 min for the Option filter, and 4.95 min for the Tulip filter (Denali vs. Option p < 0.01; Denali vs. Tulip p < 0.01; Tulip vs. Option p = 0.67). Advanced retrieval techniques were used in 0.9% of Denali filters, 21.1% in Option filters, and 10.8% in Tulip filters (Denali vs. Option p < 0.01; Denali vs. Tulip p < 0.01; Tulip vs. Option p < 0.01). DISCUSSION: Filter retrieval failure rates were significantly higher for the Option filter when compared to both the Denali and Tulip filters. Retrieval of the Denali filter required significantly less amount of fluoroscopy time and use of advanced retrieval techniques when compared to both the Option and Tulip filters. The findings of this study indicate easier retrieval of the Denali and Tulip IVC filters when compared to the Option filter.

Congenital Anomalies of the Superior Vena Cava: Embryological Correlation, Imaging Perspectives, and Clinical Relevance.

There is a wide spectrum of congenital anomalies of the superior vena cava, which are more increasingly recognized in cross-sectional imaging. Although some of these anomalies are asymptomatic, others have important clinical and interventional implications. Imaging modalities such as computed tomography and magnetic resonance imaging play an important role in the accurate characterization of these anomalies, which is essential for mapping prior to surgeries or interventions. In this article, we review a wide range of anomalies of the superior vena cava, including the embryological basis, cross-sectional imaging findings, and clinical implications, particularly from an interventional radiology perspective. We also discuss the treatments and complications of these anomalies.

Vena Cava Responsiveness to Controlled Isovolumetric Respiratory Efforts.

OBJECTIVES: Respirophasic variation of inferior vena cava (IVC) size is affected by large variability with spontaneous breathing. This study aims at characterizing the dependence of IVC size on controlled changes in intrathoracic pressure. METHODS: Ten healthy subjects, in supine position, performed controlled isovolumetric respiratory efforts at functional residual capacity, attaining positive (5, 10, and 15 mmHg) and negative (-5, -10, and -15 mmHg) alveolar pressure levels. The isovolumetric constraint implies that equivalent changes are exhibited by alveolar and intrathoracic pressures during respiratory tasks. RESULTS: The IVC cross-sectional area equal to 2.88 ± 0.43 cm2 at baseline (alveolar pressure = 0 mmHg) was progressively decreased by both expiratory and inspiratory efforts of increasing strength, with diaphragmatic efforts producing larger effects than thoracic ones: -55 ± 15% decrease, at +15 mmHg of alveolar pressure (P < .01), -80 ± 33 ± 12% at -15 mmHg diaphragmatic (P < .01), -33 ± 12% at -15 mmHg thoracic. Significant IVC changes in size (P < .01) and pulsatility (P < .05), along with non significant reduction in the response to respiratory efforts, were also observed during the first 30 minutes of supine rest, detecting an increase in vascular filling, and taking place after switching from the standing to the supine position. CONCLUSIONS: This study quantified the dependence of the IVC cross-sectional area on controlled intrathoracic pressure changes and evidenced the stronger influence of diaphragmatic over thoracic activity. Individual variability in thoracic/diaphragmatic respiratory pattern should be considered in the interpretation of the respirophasic modulations of IVC size.

Simultaneous total cavopulmonary connection and cardiac re-synchronisation therapy.

We report the simultaneous use of cardiac re-synchronisation therapy and total cavopulmonary connection in a patient with dyssynchrony, wide QRS, and cardiac failure. To our knowledge, this simultaneous approach has not been reported previously. On follow-up, we noted that QRS width and brain natriuretic peptide levels improved. In addition, speckle tracking revealed improved synchronisation of ventricular wall motion.