Surgical Anatomy of the Mesopancreas in Obese Patients: A Retrospective Study.

Introduction The mesopancreas is described as a triangle formed by the superior mesenteric vein, celiac axis (CA), and superior mesenteric artery (SMA). It is the most likely site of residual cancer and local recurrence after surgical resection, making it the key site of the current radical resection of pancreatic head cancer. The surgical anatomy of the mesopancreas triangle has not been studied in detail. Furthermore, to the best of our knowledge, no information is available on the impact of obesity on the anatomy of the mesopancreas triangle. Methods Between January 2016 and August 2016, 200 consecutive triple-phase computed tomography scans of the abdomen were performed and included in this retrospective study aiming to define the anatomical relation of the left renal vein (LRV) to the root of the SMA and focusing on the relevance of the LRV as a landmark to guidance for the dissection of the mesopancreas. Furthermore, by studying six surgically relevant anatomical parameters namely the thickness of the areolar tissue separating the LRV from the root of the SMA, IVC from the root of the SMA, the left adrenal vein (LAV) from the root of the SMA, splenic vein from the aorta, and CA from the SMA at two levels, we investigated the impact of obesity on the mesopancreas anatomy. Results The mean distance from the upper border of the LRV to the root of the SMA (LRV-SMA distance) was 2.3 ± 5.4 mm. There was no correlation between this distance and patient's age (r = -0.02), height (r = -0.07), BMI (r = -0.01), visceral fat area (r = -0.04), or abdominal circumference (r = -0.02). There was no correlation between the distance from the IVC to the root of the SMA, and patient's age (r = 0.01), height (r = 0.11), BMI (r = 0.15), or abdominal circumference (r = 0.00). However, there was a negligible correlation between the IVC-SMA distance and patient's visceral fat area (r = 0.15, p = 0.036). Conclusion In the current study, the LRV was reliably identified in more than 99% of the studied patients, and in 96% of patients, the LRV crosses anterior to the aorta at the level of the second lumbar vertebra, making it easily accessible following mobilization of the duodenum and the head of the pancreas. The relationship between the LRV and SMA remains unchanged following Kocherization. Most importantly, we demonstrated that the LRV-SMA distance does not correlate with patient's age, height, BMI, visceral fat area, or abdominal circumference. This makes the LRV a reliable landmark in both obese and non-obese patients.

Reversal of right ventricular pressure loading improves biventricular function independent of fibrosis in a rabbit model of pulmonary artery banding.

Right ventricular (RV) pressure loading leads to RV and left ventricular (LV) dysfunction through RV hypertrophy, dilatation and fibrosis. Relief of RV pressure load improves RV function. However, the impact and mechanisms on biventricular reverse-remodelling and function are only partially characterized. We evaluated the impact of RV pressure overload relief on biventricular remodelling and function in a rabbit model of reversible pulmonary artery banding (PAB). Rabbits were randomized to three groups: (1) Sham-operated controls (n = 7); (2) PAB (NDef, n = 7); (3) PAB followed by band deflation (Def, n = 5). Sham and NDef animals were sacrificed at 6 weeks after PAB surgery. Def animals underwent PAB deflation at 6 weeks and sacrifice at 9 weeks. Biventricular geometry, function, haemodynamics, hypertrophy and fibrosis were compared between groups using echocardiography, magnetic resonance imaging, high-fidelity pressure-tipped catheters and histology. RV pressure loading caused RV dilatation, systolic dysfunction, myocyte hypertrophy and LV compression which improved after PAB deflation. RV end-diastolic pressure (RVEDP) decreased after PAB deflation, although remaining elevated vs. Sham. LV end-diastolic pressure (LVEDP) was unchanged following PAB deflation. RV and LV collagen volumes in the NDef and Def group were increased vs. Sham, whereas RV and LV collagen volumes were similar between NDef and Def groups. RV myocyte hypertrophy (r = 0.75, P < 0.001) but not collagen volume was related to RVEDP. LV myocyte hypertrophy (r = 0.58, P = 0.016) and collagen volume (r = 0.56, P = 0.031) correlated with LVEDP. In conclusion, relief of RV pressure overload improves RV and LV geometry, hypertrophy and function independent of fibrosis. The long-term implications of persistent fibrosis and increased biventricular filling pressures, even after pressure load relief, need further study. KEY POINTS: Right ventricular (RV) pressure loading in a pulmonary artery banding rabbit model is associated with RV dilatation, left ventricular (LV) compression; biventricular myocyte hypertrophy, fibrosis and dysfunction. The mechanisms and impact of RV pressure load relief on biventricular remodelling and function has not been extensively studied. Relief of RV pressure overload improves biventricular geometry in conjunction with improved RV myocyte hypertrophy and function independent of reduced fibrosis. These findings raise questions as to the importance of fibrosis as a therapeutic target.

Right Ventricular Mass 12 Years after Osteosarcoma: Multimodality Imaging with Pathologic Correlation.

The authors report a 27-year-old woman with a remote left femoral osteosarcoma and amputation above the left knee who presented with a large right ventricular mass. Initial evaluation with thoracic CT was inconclusive regarding thrombus versus tumor, but metastatic osteosarcoma was suggested by findings at transthoracic echocardiography, cardiac CT, and cardiac MRI. The patient underwent tumor debulking, and osteosarcoma was confirmed with pathologic examination. She responded to chemotherapy, which resulted in reduction in size of the residual right ventricular tumor and of a few pulmonary metastases. Following induction chemotherapy, patient remains well undergoing maintenance therapy with an oral tyrosine kinase inhibitor. Keywords: CT, Echocardiography, MR Imaging, Intraoperative, Cardiac, Heart, Right Ventricle, Imaging Sequences, Metastases, Oncology Supplemental material is available for this article. © RSNA, 2021.

Bentall procedure for the repair of a neoaortic aneurysm after the Norwood procedure in a patient with tricuspid atresia and a discordant ventriculo-arterial connection.

Neoaortic root dilation is a common phenomenon after the Norwood procedure, but the real incidence and its natural history are unclear. Regular surveillance in these patients after the operation is necessary. Herein, we present an 11-year-old boy born with tricuspid atresia, a discordant ventriculo-arterial connection and a hypoplastic aortic arch, who was palliated initially with a hybrid stage I procedure involving a reversed Blalock-Taussig shunt, followed by comprehensive stage II and then, an extra-cardiac fenestrated Fontan operation. The patient developed an aortic root aneurysm and severe aortic regurgitation. He was electively taken into the operating room, where cardiopulmonary bypass was established through a peripheral cannulation of the femoral vessels due to the high risk nature of the reoperation. A mechanical Bentall procedure was performed without residual lesions and the native ascending aorta was anastomosed as a single coronary button to the anterior wall of the graft.