Direct lymphangiography-guided cervical thoracic duct exploration for isolated primary chylopericardium: Abnormal reflux patterns and long-term outcomes.

BACKGROUND

Primary chylopericardium is a rare lymphatic disorder with poorly defined pathophysiology and limited treatment options. This study aimed to characterize lymphangiographic reflux patterns and evaluate the long-term outcomes and predictors of success of direct lymphangiography-guided cervical thoracic duct exploration.

METHODS

We retrospectively reviewed 67 patients with isolated primary chylopericardium who underwent direct lymphangiography between June 2007 and December 2020. A novel 4-type classification of abnormal reflux pathways was proposed based on direct lymphangiography findings. Treatment success was defined as resolution or marked reduction of pericardial effusion, relief of symptoms, and no need for reintervention. Median follow-up was 10.2 years (range, 7.5-19.5 years). Multivariable logistic regression was performed to identify independent predictors of success.

RESULTS

Direct lymphangiography demonstrated distinct reflux patterns: type I (bronchomediastinal trunk, 55.2%), type II (thoracic segment, 11.9%), type III (combined, 7.5%), and type IV (no identifiable pathway, 28.4%). Compensatory drainage was present in 25.4% of patients. Among 65 patients who underwent cervical thoracic duct exploration, the clinical success rate was 66.2% (43/65), with no major complications. Multivariable analysis showed that the absence of compensatory drainage pathways was the strongest independent predictor of success (adjusted odds ratio, 7.85; 95% confidence interval, 1.48-41.6; P = .016). Reflux pathway type was also independently associated with outcome (P = .012), with type I demonstrating better results than types II-IV. Conservative dietary management alone was ineffective in the 2 patients who did not undergo surgery.

CONCLUSION

Direct lymphangiography-guided cervical thoracic duct exploration is associated with favorable long-term outcomes in selected patients with primary chylopericardium. The proposed reflux classification and the absence of compensatory drainage pathways were strong predictors of success. These findings are preliminary and require prospective multicenter validation.