UNASSIGNED: Chylopericardium refers to the accumulation of chylous fluid in the pericardial cavity. Non-enhanced magnetic resonance lymphangiography (MRL) can show neck and thoracic lymphatic abnormalities in the primary chylopericardium. It is not clear whether there is a relationship between neck and thoracic lymphatic abnormalities in primary chylopericardium and thoracic duct terminal release surgery. This study aimed to explore the correlation between the severity of neck and thoracic lymphatic abnormalities observed in non-enhanced MRL and the surgical outcomes in primary chylopericardium.
UNASSIGNED: This is a retrospective cohort study. A retrospective analysis was conducted on fifty-six patients diagnosed with primary chylopericardium between January 2016 and December 2021, all of whom underwent thoracic duct terminal release surgery. Ultrasonography, chest computed tomography (CT) and non-enhanced MRL were performed prior to the surgical intervention. Patients were categorized into four types based on the severity of neck and thoracic lymphatic abnormalities observed in the non-enhanced MRL. Clinical and laboratory examinations and surgical outcomes were compared across different types using χ 2-test or Fisher\'s exact test, t-test, and Kruskal-Wallis H-test. Additionally, independent factors influencing surgical outcomes were analyzed.
UNASSIGNED: Among primary chylopericardium cases (n=56), 22 (39.2%) were classified as type I or II, 17 (30.4%) as type III, and 17 (30.4%) as type IV. Surgical outcomes were more favorable for type I or II patients than those with type III or IV, accompanied by a reduction in postoperative primary chylopericardium volume (P=0.002). Postoperative chest CT scans indicated that type I or II patients had fewer instances of large grid shadows, small grid shadows, and bronchovascular bundle thickening compared to preoperative scans (P=0.001, P=0.02, P=0.03). Age and bronchomediastinal trunk dilation emerged as independent factors influencing surgical outcomes [odds ratio (OR) 0.03, 95% confidence interval (CI): 0.003-0.220, P=0.001; OR 11.10, 95% CI: 1.70-72.39, P=0.01, respectively].
UNASSIGNED: A more severe degree of neck and thoracic lymphatic abnormalities is associated with worse surgical outcomes. Moreover, age and bronchomediastinal trunk dilatation are independent predictors of surgical outcomes. Preoperative utilization of non-enhanced MRL for severity of lymphatic abnormalities classification in primary chylopericardium patients offers a noninvasive means of assessing surgical risk.

Background: The thoracic duct (TD) and the cisterna chyli (CC) exhibit a high degree of variability in their topographical and morphometric properties. Materials and Methods: PubMed, Scopus, Embase, Web of Science, Cochrane Library, and Google Scholar were searched to identify all studies that included information regarding the morphometric and topographical characteristics of the TD and CC. Results: The most frequent location of the TD termination was the left venous angle, with a pooled prevalence of 45.29% (95% CI: 25.51-65.81%). Moreover, the TD terminated most commonly as a single vessel (pooled prevalence = 78.41%; 95% CI: 70.91-85.09%). However, it divides into two or more terminating branches in approximately a quarter of the cases. The pooled prevalence of the CC was found to be 55.49% (95% CI: 26.79-82.53%). Conclusions: Our meta-analysis reveals significant variability in the anatomy of the TD and CC, particularly regarding TD termination patterns. Despite the predominance of single-vessel terminations, almost a quarter of cases exhibit branching, highlighting the complexity of the anatomy of the TD. These findings demonstrate the importance of detailed anatomical knowledge for surgeons to minimize the risk of accidental injury during head and neck, as well as thoracic surgeries. Our study provides essential insights that can enhance surgical safety and efficacy, ultimately improving patient outcomes.

A chylothorax, the accumulation of lymphatic fluid in the pleural space, may occur for a variety of reasons. It is commonly seen in adults post-thoracic surgery. We present the case of a seven-month-old girl with a right-sided chylothorax in the setting of non-accidental trauma. Treatment options for a chylothorax include surgical ligation of the thoracic duct or, as in this case, a minimally invasive procedure performed by interventional radiology known as lymphangiography with thoracic duct embolization. This case highlights interventional radiologists\' ability to treat complex lymphatic pathologies effectively with minimally invasive techniques.

BACKGROUND: Disordered lymphatic drainage is common in congenital heart diseases (CHD), but thoracic duct (TD) drainage patterns in heterotaxy have not been described in detail. This study sought to describe terminal TD sidedness in heterotaxy and its associations with other anatomic variables.
METHODS: This was a retrospective, single-center study of patients with heterotaxy who underwent cardiovascular magnetic resonance imaging at a single center between July 1, 2019 and May 15, 2023. Patients with (1) asplenia (right isomerism), (2) polysplenia (left isomerism) and (3) pulmonary/abdominal situs inversus (PASI) plus CHD were included. Terminal TD sidedness was described as left-sided, right-sided, or bilateral.
RESULTS: Of 115 eligible patients, the terminal TD was visualized in 56 (49 %). The terminal TD was left-sided in 25 patients, right-sided in 29, and bilateral in two. On univariate analysis, terminal TD sidedness was associated with atrial situs (p = 0.006), abdominal situs (p = 0.042), type of heterotaxy (p = 0.036), the presence of pulmonary obstruction (p = 0.041), superior vena cava sidedness (p = 0.005), and arch sidedness (p < 0.001). On multivariable analysis, only superior vena cava and aortic arch sidedness were independently associated with terminal TD sidedness.
CONCLUSIONS: Terminal TD sidedness is highly variable in patients with heterotaxy. Superior vena cava and arch sidedness are independently associated with terminal TD sidedness. Type of heterotaxy was not independently associated with terminal TD sidedness. This data improves the understanding of anatomic variation in patients with heterotaxy and may be useful for planning for lymphatic interventions.

Lymphatic disorders in congenital heart disease can be broadly classified into chest compartment, abdominal compartment, or multicompartment disorders. Heavily T2-weighted noninvasive lymphatic imaging (for anatomy) and invasive dynamic contrast magnetic resonance lymphangiography (for flow) have become the main diagnostic modalities of choice to identify the cause of lymphatic disorders. Selective lymphatic duct embolization (SLDE) has largely replaced total thoracic duct embolization as the main lymphatic therapeutic procedure. Recurrence of symptoms needing repeat interventions is more common in patients who underwent SLDE. Novel surgical and transcatheter thoracic duct decompression strategies are promising, but long-term follow-up is critical and eagerly awaited.

Percutaneous endovascular techniques established in interventional cardiology and radiology are well-suited for managing lymphatic conduction disorders. In this article, we provide a synopsis of technical aspects of these procedures, including access of the thoracic duct, selective lymphatic embolization, and management of thoracic duct obstruction. In aggregate, these techniques have developed into an integral component of multidisciplinary management of these complex diseases.

Congenital heart disease affects 1/100 live births and is one of the most common congenital abnormalities. The relationship between congenital heart disease and lymphatic abnormalities and/or dysfunction is well documented and can be grossly divided into syndromic and non-syndromic etiologies. In patients with genetic syndromes (as examples listed above), there are known primary abnormal lymphatic development leading to a large pleiotropic manifestation of lymphatic dysfunction. Non-syndromic patients, or those without clear genetic etiologies for their lymphatic dysfunction, are often thought to be secondary to physiologic abnormalities as sequelae of congenital heart disease and palliative surgeries. Patients with congenital heart disease and lymphatic dysfunction have a wide variety of clinical manifestations for which there were not many therapeutic interventions available. The development of new imaging techniques allows us to understand better the pathophysiology of these problems and to develop different percutaneous interventions aiming to restore normal lymphatic function.

OBJECTIVE: The thoracic duct is the largest lymphatic vessel in the body, and carries fluid and nutrients absorbed in abdominal organs to the central venous circulation. Thoracic duct obstruction can cause significant failure of the lymphatic circulation (i.e., protein-losing enteropathy, plastic bronchitis, etc.). Surgical anastomosis between the thoracic duct and central venous circulation has been used to treat thoracic duct obstruction but cannot provide lymphatic decompression in patients with superior vena cava obstruction or chronically elevated central venous pressures (e.g., right heart failure, single ventricle physiology, etc.). Therefore, this preclinical feasibility study sought to develop a novel and optimal surgical technique for creating a thoracic duct-to-pulmonary vein lymphovenous anastomosis (LVA) in swine that could remain patent and preserve unidirectional lymphatic fluid flow into the systemic venous circulation to provide therapeutic decompression of the lymphatic circulation even at high central venous pressures.
METHODS: A thoracic duct-to-pulmonary vein LVA was attempted in 10 piglets (median age 80 [IQR 80-83] days; weight 22.5 [IQR 21.4-26.8] kg). After a right thoracotomy, the thoracic duct was mobilized, transected, and anastomosed to the right inferior pulmonary vein. Animals were systemically anticoagulated on post-operative day 1. Lymphangiography was used to evaluate LVA patency up to post-operative day 7.
RESULTS: A thoracic duct-to-pulmonary vein LVA was successfully completed in 8/10 (80.0%) piglets, of which 6/8 (75.0%) survived to the intended study endpoint without any complication (median 6 [IQR 4-7] days). Initially, 2/10 (20.0%) LVAs were aborted intraoperatively, and 2/10 (20.0%) animals were euthanized early due to post-operative complications. However, using an optimized surgical technique, the success rate for creating a thoracic duct-to-pulmonary vein LVA in six animals was 100%, all of which survived to their intended study endpoint without any complications (median 6 [IQR 4-7] days). LVAs remained patent for up to seven days.
CONCLUSIONS: A thoracic duct-to-pulmonary vein LVA can be completed safely and remain patent for at least one week with systemic anticoagulation, which provides an important proof-of-concept that this novel intervention could effectively offload the lymphatic circulation in patients with lymphatic failure and elevated central venous pressures.

The development of new imaging techniques for the study of the central lymphatic system allows us to understand the anatomy and pathophysiology of all the disorders of the thoracic duct. With the help of catheters placed percutaneously in the thoracic duct, we can do now complex operations on the thoracic duct to restore its functionality. Advance imaging, expert percutaneous skills, and expert microsurgical skills are critical to the success of these interventions.

Surgical decompression of the thoracic outlet, along with treatment of the involved nerve or vessel, is the accepted treatment modality when indicated. Although neurogenic thoracic outlet syndrome (TOS) is often operated via the axillary approach and venous TOS via the paraclavicular approach, arterial TOS is almost always operated via the supraclavicular approach. The supraclavicular approach provides excellent access to the artery, brachial plexus, phrenic nerve, and the cervical and/or first ribs, along with any bony or fibrous or muscular abnormality that may be causing compression of the neurovascular structures. Even for neurogenic TOS, for which the axillary approach offers good cosmesis, the supraclavicular approach helps with adequate decompression while preserving the first rib. This approach may also be sufficient for thin patients with venous TOS. For arterial TOS, a supraclavicular incision usually suffices for excision of bony abnormality and repair of the subclavian artery.