Pericardial fenestration and thoracic duct ligation for treatment of chylopericardium as first symptom of underlying generalized lymphatic anomaly: a case report.

INTRODUCTION: Chylopericardium represents a rare condition of chyle accumulation within the pericardial sac, caused by abnormal thoracic duct anatomy or prolonged increased pressure. Nothing by mouth (NPO) policy and total parenteral nutrition (TPN), even in combination with pericardial drainage, render only a temporary solution. Surgical intervention with thoracic duct ligation and creation of a pericardial window is believed to be the most effective treatment. CASE PRESENTATION: An 18-year-old male was referred with a persisting idiopathic chylopericardium for five months. Various drainages and conservative treatment failed. To more permanently treat the chylopericardium, we created a pericardial window and ligated the thoracic duct by right-sided uniportal video-assisted thoracoscopic surgery. Postoperative NPO and TPN for 1 week were initiated, followed by medium-chain-triglycerides diet for 1 week. Clinical improvement occurred and the chest drain was removed two weeks after surgery. Magnetic resonance imaging of the whole body showed multiple cystic lesions in spleen and skeleton compatible with generalized lymphatic anomaly (GLA), proven by the anatomopathological examination of the thoracic duct and lung biopsy. Sirolimus was initiated for further treatment. CONCLUSION: In this case of idiopathic chylopericardium, we successfully performed thoracoscopic thoracic duct ligation and creation of a pericardial window, diagnosing a GLA.

Systematic Review of Robotic-Assisted Peripheral and Central Lymphatic Surgery.

BACKGROUND: Robotic-assisted lymphatic reconstruction has gained increasing interest over the past few years. OBJECTIVES: The aim of this study was to systematically investigate the benefits of robotic-assisted lymphatic surgery based on currently published literature. METHODS: A systematic review evaluating the feasibility, surgical aspects, and both objective and subjective improvements in patients with impairment of the peripheral or central lymphatic system was performed according to the PRISMA guidelines. The review was registered on PROSPERO. RESULTS: The literature search yielded 328 articles after the removal of duplicates, followed by a full-text review of the 29 articles, out of which a total of 11 relevant articles were deemed eligible. Among these, seven used a retrospective design and four a prospective design. All studies included confirmed the feasibility of robotic-assisted lymphatic surgery and reported promising results concerning both technical aspects and patient-related outcomes. However, currently, only a limited number of studies directly compare the robotic-assisted approach to the manual approach, and these studies have limited statistical analyses. CONCLUSION: Despite the heterogeneous measurands, all studies showed the feasibility of robotic-assisted lymphatic surgery, and seven provided promising data on patient-related outcomes. Additional studies are needed to further identify future directions in robotic-assisted lymphatic surgery.

Generalized lymphangiomatosis in patients treated for chylothorax following thoracoscopic sympathectomy: Case report.

Generalized lymphangiomatosis (GLA) is a very rare condition in adults, characterized by diffused proliferation of lymphatic vessels that requires differential diagnosis from other vascular disorders such as cavernous or capillary hemangioma. This is because of overlapping characteristics on histopathological examination. Therefore, imaging features such as CT and MRI are useful to evaluate morphological characteristics, location, and the extent of the spread as well as differential diagnosis with other pathologies. We report a case of a 22-year-old female patient with left hemothorax after thoracoscopic sympathectomy for the treatment of hand sweating. The patient underwent drainage and cleaning of the left pleura. Chest computed tomography and lumbar spine magnetic resonance imaging showed multiple fat infiltration foci of the lumbar spine and pelvis. A wing bone biopsy of the pelvis was initially performed for the diagnosis of chronic osteomyelitis. Afterwards, the patient continued to have pleural drainage and developed hemothorax and chylothorax, amounting to 3000 mL. The chest tube was blocked with a mixture of biological glue and lipiodol (2 mL of glue, ratio of glue to lipiodol: 1:4) and a 3 i-ED coil complex. After the intervention, the pleural fluid decreased; the left pleural fluid was still 15 mm thick, and the amount of fluid drained after 1 week was 100 mL. Aspiration of the chest wall lesion showed fluid rich in fat droplets. Combined with the results of lumbar spine magnetic resonance imaging and the old biopsy, this was consistent with generalized lymphangiomatosis.

Selective Lymphatic Duct Embolization for Treatment of Thoracic Lymphatic Flow Disorders in Children: Technical Aspects and Comparison with Thoracic Duct Embolization.

PURPOSE: To assess effectiveness of selective lymphatic duct embolization (SLDE) for treatment of thoracic lymphatic flow disorders, performed to maintain patency of the thoracic duct (TD), compared to thoracic duct embolization (TDE). MATERIALS AND METHODS: Records of 39 patients (mean age 7.6±7.1 years) with thoracic lymphatic flow disorders who underwent 43 SLDE procedures were analyzed and compared to a cohort of 104 patients (7.8±7.6 y) who underwent TDE. Relevant clinical and imaging data were collated. All patients presented with chylous effusion and/or plastic bronchitis. For the SLDE cohort, etiology of disorders included single-ventricle heart disease palliation in 28 patients (72%) and vascular malformation/aneuploidy in 8 (21%). For the TDE cohort, 92/104(88%) had single-ventricle heart disease palliation. RESULTS: SLDE was performed with glue via microcatheter in 35 procedures, and dextrose flood technique was used in 26. SLDE via direct needle access was performed in 11. After SLDE, presenting symptoms resolved in 33/39 patients (85%), improved in 5 (13%), and were unchanged in 1 (3%) (mean follow-up 693±523 days). The TD remained patent in all cases. There was a significant difference in outcomes (P=0.001) with the TDE cohort-symptoms resolved or improved in 75/104 patients (72%), were unchanged in 15 (14%); and new leak (e.g., ascites, protein-losing enteropathy) developed in 14 TDE patients (13%) (follow-up 1041±879 d). CONCLUSION: SLDE was effective for treatment of thoracic lymphatic flow disorders, and outcomes were comparable to TDE. Selective techniques preserve the patency of the TD and may have potential benefits that warrant further study.

Pediatric Chylothorax Treated With Lymphangiography and Thoracic Duct Embolization: A Case Report.

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.

The Anatomy of the Thoracic Duct and Cisterna Chyli: A Meta-Analysis with Surgical Implications.

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.

Resolution of Persistent Chylothorax With a Ketogenic Diet: A Case Report.

This is the first case report of a very low-carbohydrate, high-fat ketogenic diet for the treatment of chylothorax. A 61-year-old female with recurrent chylothorax following thoracic surgery was refractory to a very low-fat diet managed by a hospital dietitian. She required repeated palliative thoracentesis to the point where she was scheduled for a thoracic duct embolization. Prior to the embolization, she was placed on a very low-carbohydrate (<20 total grams daily), high-fat, ketogenic diet. Metabolic markers and imaging were obtained regularly. The patient had improvements in her serum triglycerides, triglyceride/HDL ratio, and triglyceride-glucose index, as well as clinical and radiographic improvements in her chylothorax as assessed by a chest X-ray and CT scan. Within three months of starting her ketogenic diet, imaging revealed complete resolution of the chylous pleural effusion. This case suggests that metabolic optimization to decrease insulin resistance, improve chylomicron metabolism, decrease lymphatic permeability, and lower serum triglycerides, as occurs with a ketogenic diet, should be considered for conservative treatment of chylothorax and warrants further study.

Association between lymphatic abnormalities in the neck and thorax in primary chylopericardium and surgical outcomes evaluated by non-enhanced magnetic resonance (MR) lymphangiography.

Background: 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. Methods: 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. Results: 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]. Conclusions: 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.

Diagnostic value of combined CT lymphangiography and 99Tcm-DX lymphoscintigraphy in primary chylopericardium.

OBJECTIVE: To investigate the diagnostic value of combined 99Tcm-DX lymphoscintigraphy and CT lymphangiography (CTL) in primary chylopericardium. METHODS: Fifty-five patients diagnosed with primary chylopericardium clinically were retrospectively analyzed. 99Tcm-DX lymphoscintigraphy and CTL were performed in all patients. Primary chylopericardium was classified into three types, according to the 99Tcm-DX lymphoscintigraphy results. The evaluation indexes of CTL include: (1) abnormal contrast distribution in the neck, (2) abnormal contrast distribution in the chest, (3) dilated thoracic duct was defined as when the widest diameter of thoracic duct was > 3 mm, (4) abnormal contrast distribution in abdominal. CTL characteristics were analyzed between different groups, and P < 0.05 was considered a statistically significant difference. RESULTS: Primary chylopericardium showed 12 patients with type I, 14 patients with type II, and 22 patients with type III. The incidence of abnormal contrast distribution in the posterior mediastinum was greater in type I than type III (P = 0.003). The incidence of abnormal contrast distribution in the pericardial and aortopulmonary windows, type I was greater than type III (P = 0.008). And the incidence of abnormal distribution of contrast agent in the bilateral cervical or subclavian region was greater in type II than type III (P = 0.002). CONCLUSION: The combined application of the 99Tcm-DX lymphoscintigraphy and CTL is of great value for the localized and qualitative diagnosis of primary chylopericardium and explore the pathogenesis of lesions.

The right lymphatic duct: basic anatomy and clinical relevance.

The anatomical variability of the thoracic duct and the right lymphatic duct predisposes them to inadvertent damage following head and neck surgery thereby leading to chyle leak which is an uncommon complication with potentially significant associated morbidity. Although chyle leak is predominately associated with left-sided neck surgery, it also occurs as a complication of the right-sided neck dissection. Variable figures concerning chyle leakage after right-sided neck dissections were reported, ranging from 0 per cent to higher prevalences such as 14%, 24%, 33% and 60% of total cases of chyle leakages associated with neck surgery. The right-sided complications may implicate the right lymphatic duct and right-sided terminations of the thoracic duct into the venous system which occur in about 1-6% of humans. Other clinically relevant conditions involving the right-sided major lymphatic vessels include chyle leaks following right anterior cervical spine surgery, cysts of the right lymphatic duct and dilatation of the right lymphatic duct in the setting of recurrent cervical swelling. This article presents a review of the literature concerning the basic anatomy and the clinical relevance of the right lymphatic duct and the right-sided terminations of the thoracic duct into the venous circulation.

Retrograde Transvenous Thoracic Duct Embolization for Tubercular Chylothorax.

This case study documents the clinical profile of a 27-year-old male patient who visited the medical facility two months ago with complaints of dry cough, fatigue, weight loss, and occasional fever. He had been treated for ascites and pleural effusion in the hospital before presentation and returned with an intercostal drain in place. A detailed examination revealed symptoms of respiratory disorders, including fluid in both lungs, fever, and dyspnea. His fluid levels showed multiple deviations from the normal range, according to the report's findings and lab test results. It was determined that the patient had chylothorax, which resulted from hemophagocytic lymphohistiocytosis (HLH) and abdominal tubercular lymphadenopathy. His anti-tubercular treatment (AKT4) was initiated, along with octreotide for his management. Initial management included non-invasive ventilator (NIV) support, intravenous antibiotics, nebulization, and an intercostal chest drain (ICD). Later, the patient underwent retrograde transvenous thoracic duct embolization (TDE) using N-butyl cyanoacrylate (NBCA) glue. The removal of the drainage tube and the patient's stable discharge were made possible through regular monitoring and collaboration between specialists.

Integrated proteomic and metabolomic profiling of lymph after trauma-induced hypercoagulopathy and antithrombotic therapy.

BACKGROUND: Routine coagulation tests are not widely accepted diagnostic criteria of trauma-induced hypercoagulopathy (TIH) due to insensitivity. Lymphatic vessels drain approximately 10% of the interstitial fluid into the lymphatic system and form lymph. SUBJECTIVE: The purpose of this study was to identify the potential lymph biomarkers for TIH. METHODS: Eighteen male Sprague-Dawley rats were randomly assigned to the sham (non-fractured rats with sham surgery and vehicle treatment), the VEH (fractured rats with vehicle treatment) and the CLO (fractured rats with clopidogrel treatment) group. Thoracic duct lymph was obtained to perform proteomics and untargeted metabolomics. RESULTS: A total of 1207 proteins and 16,695 metabolites were identified. The top 5 GO terms of lymph proteomics indicated that oxidative stress and innate immunity were closely associated with TIH and antithrombotic therapy. The top 5 GO terms of lymph metabolomics showed that homocystine and lysophosphatidylcholine were the differential expressed metabolites (DEMs) between the sham and VEH groups, while cholic acid, docosahexaenoic acid, N1-Methyl-2-pyridone-5-carboxamide, isoleucine and testosterone are the DEMs between the VEH and CLO group. CONCLUSIONS: This study presents the first proteomic and metabolomic profiling of lymph after TIH and antithrombotic therapy, and predicts the possible lymph biomarkers for TIH.

Impact of Thoracic Duct Resection on Long-Term Survival After Esophagectomy: Individual Patient Data Meta-analysis.

BACKGROUND: Radical esophagectomy, including thoracic duct resection (TDR), has been proposed to improve regional lymphadenectomy and possibly reduce the risk of locoregional recurrence. However, because of its impact on immunoregulation, some authors have expressed concerns about its possible detrimental effect on long-term survival. The purpose of this review was to assess the influence of TDR on long-term survival. PATIENTS AND METHODS: PubMed, MEDLINE, Scopus, and Web of Science databases were searched through 15 March 2024. Overall survival (OS), cancer specific survival (CSS), and disease-free survival (DFS) were primary outcomes. Restricted mean survival time difference (RMSTD), risk ratio (RR), standardized mean difference (SMD), and 95% confidence intervals (CI) were used as pooled effect size measures. The Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) methodology was employed to evaluate the certainty of evidence. RESULTS: The analysis included six studies with 5756 patients undergoing transthoracic esophagectomy. TDR was reported in 49.1%. Patients' ages ranged from 27 to 79 years and 86% were males. At 4-year follow-up, the multivariate meta-analysis showed similar results for the comparison noTDR versus TDR in term of OS [- 0.8 months, 95% confidence interval (CI) - 3.1, 1.3], CSS (0.1 months, 95% CI - 0.9, 1.2), and DFS (1.5 months, 95% CI - 2.6, 5.5). TDR was associated with a significantly higher number of harvested mediastinal lymph nodes (SMD 0.57, 95% CI 0.01-1.13) and higher risk of postoperative chylothorax (RR = 1.32; 95% CI 1.04-2.23). Anastomotic leak and pulmonary complications were comparable. CONCLUSIONS: TDR seems not to improve long-term OS, CSS, and DFS regardless of tumor stage. Routine TDR should not be routinely recommended during esophagectomy.

Successful Thoracic Duct Embolization Following Fontan-Related Chylothorax in a Six-Year-Old Girl: A Case Report.

Chylothorax is a severe complication following the Fontan procedure, causing significant morbidity and mortality due to nutritional depletion and fluid loss. We present a case involving a six-year-old girl with tricuspid atresia, atrial septal defect (ASD), ventricular septal defect (VSD), and severe pulmonary stenosis (PS), presenting with fever, non-productive cough, and increased work of breathing. Cyanosis was noted, improving with oxygen. Imaging revealed bilateral pleural effusion, with pleural fluid analysis confirming chylothorax. Despite normal laboratory reports, retrograde transvenous lymphangiography indicated thoracic duct leakage. The patient underwent successful thoracic duct embolization, resulting in the resolution of the effusion and stabilization of her condition. She was discharged in a stable state, with follow-up care.

Delayed chylous fluid leakage at the surgical site following thoracic corpectomy via a lateral extracavitary approach: illustrative case.

BACKGROUND: Chylous fluid leakage following spinal surgery is a rare and potentially difficult-to-manage complication that can lead to wound complications, pain, or nutritional deficiencies. Although the thoracic duct is localized near the thoracic spine, reports of thoracic duct injuries secondary to posterior thoracic spine surgery are rare. OBSERVATIONS: The authors present the case of a 57-year-old male with a known history of metastatic renal cell carcinoma to the thoracic spine who had undergone a thoracolumbar fusion with thoracic corpectomy and presented with concern for a chyle leak almost a year after his surgery. The patient had a complicated oncological history and underwent decompression and fusion to treat his significant thoracic metastatic disease. A year later, he presented with back pain and a significant fluid collection at the surgical site, which was drained and found to be consistent with chyle. The patient was treated conservatively, and imaging of the thoracic duct a few months later demonstrated no direct injury, likely indicating either transient injury or potential obstruction of the thoracic duct from metastatic disease. LESSONS: This case demonstrates a rare, potential complication when treating extensive thoracic metastatic disease as well as the workup and potential treatments when facing thoracic duct injury. https://thejns.org/doi/10.3171/CASE24280.

Microsurgical central lymphatic reconstruction-the role of thoracic duct lymphovenous anastomoses at different anatomical levels.

Introduction: In recent years advances have been made in the microsurgical treatment of congenital or acquired central lymphatic lesions. While acquired lesions can result from any surgery or trauma of the central lymphatic system, congenital lymphatic lesions can have a variety of manifestations, ranging from singular thoracic duct abnormalities to complex multifocal malformations. Both conditions may cause recurrent chylous effusions and downstream lymphatic congestion depending on the anatomical location of the thoracic duct lesion and are associated with an increased mortality due to the permanent loss of protein and fluid. Methods: We present a case series of eleven patients undergoing central lymphatic reconstruction, consisting of one patient with a cervical iatrogenic thoracic duct lesion and eleven patients with different congenital thoracic duct lesions or thrombotic occlusions. Results: Anastomosis of the thoracic duct and a nearby vein was performed on different anatomical levels depending on the underlying central lymphatic pathology. Cervical (n = 4), thoracic (n = 1) or abdominal access (n = 5) was used for central lymphatic reconstruction with promising results. In 9 patients a postoperative benefit with varying degrees of symptom regression was reported. Conclusion: The presented case series illustrates the current rapid advances in the field of central microsurgical reconstruction of lymphatic lesions alongside the relevant literature.

Lymphatic Interventions in Congenital Heart Disease.

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.

VATS thoracic duct clipping in post-CABG with chylothorax.

Post-coronary artery bypass graft (CABG) surgery, chylothorax is a rare, but a serious, complication. We report a case of 49-year-old female who underwent CABG, and developed pleural effusion on post-operative day 2 which was milky in nature. Chylothorax was confirmed based on the biochemical analysis of the pleural fluid. As the medical line of management failed, video-assisted thoracoscopic surgery (VATS) was done and thoracic duct clipped on the right side. Close to the proximal portion of the left internal thoracic artery, disrupted tributaries of thoracic duct were noted and clipped. Rarity of the case and management is highlighted.

Lymphatic interventions in congenital heart disease.

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.

Thoracic duct drainage patterns in heterotaxy.

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.