Delayed Presentation of Endovenous Heat-Induced Thrombosis Treated by Thrombolysis and Subsequent Open Thrombectomy

Current status of endothermal heat induced thrombosis

BACKGROUND

There remain many questions regarding the pathophysiology and risk factors for endothermal heat induced thrombosis formation. Moreover, there are a paucity of data on the timing of its occurrence, and there has been no consensus regarding for its treatment. The purpose of this review is to summarize the current knowledge on the pathophysiology, risk factors and treatment strategies for endothermal heat induced thrombosis.

METHODS

The PubMed database was searched from 2001 to present for endothermal heat induced thrombosis, EHIT, deep vein thrombosis, chronic venous insufficiency, varicose veins, endovenous laser and radiofrequency ablation (treatment). All relevant articles identified by the authors mentioning endothermal heat induced thrombosis were included in this review.

RESULTS

A multitude of risk factors, several pathophysiological hypotheses and different treatment strategies are described in the literature.

CONCLUSIONS

Endothermal heat induced thrombosis is marginally understood. There remains a theoretical risk for significant venous thromboembolic complications. With the new uniform classification of EHIT (American Venous Forum), healthcare providers should continue to investigate the nature of this event.

Classification and treatment of endothermal heat-induced thrombosis: Recommendations from the American Venous Forum and the Society for Vascular Surgery

The American Venous Forum (AVF) and the Society for Vascular Surgery set forth these guidelines for the management of endothermal heat-induced thrombosis (EHIT). The guidelines serve to compile the body of literature on EHIT and to put forth evidence-based recommendations. The guidelines are divided into the following categories: classification of EHIT, risk factors and prevention, and treatment of EHIT. One major feature is to standardize the reporting under one classification system. The Kabnick and Lawrence classification systems are now combined into the AVF EHIT classification system. The novel classification system affords standardization in reporting but also allows continued combined evaluation with the current body of literature. Recommendations codify the use of duplex ultrasound for the diagnosis of EHIT. Risk factor assessments and methods of prevention including mechanical prophylaxis, chemical prophylaxis, and ablation distance are discussed. Treatment guidelines are tailored to the AVF EHIT class (ie, I, II, III, IV). Reference is made to the use of surveillance, antiplatelet therapy, and anticoagulants as deemed indicated, and the recommendations incorporate the use of the novel direct oral anticoagulants. Last, EHIT management as it relates to the great and small saphenous veins is discussed.

Classification and treatment of endothermal heat-induced thrombosis: Recommendations from the American Venous Forum and the Society for Vascular Surgery This Practice Guidelines document has been co-published in Phlebology [DOI: 10.1177/0268355520953759] and Journal of Vascular Surgery: Venous and Lymphatic Disorders [DOI: 10.1016/j.jvsv.2020.06.008]. The publications are identical except for minor stylistic and spelling differences in keeping with each journal's style. The contribution has been published under a Attribution-Non Commercial-No Derivatives 4.0 International (CC BY-NC-ND 4.0), (https://creativecommons.org/licenses/by-nc-nd/4.0/)

The American Venous Forum (AVF) and the Society for Vascular Surgery set forth these guidelines for the management of endothermal heat-induced thrombosis (EHIT). The guidelines serve to compile the body of literature on EHIT and to put forth evidence-based recommendations. The guidelines are divided into the following categories: classification of EHIT, risk factors and prevention, and treatment of EHIT.

One major feature is to standardize the reporting under one classification system. The Kabnick and Lawrence classification systems are now combined into the AVF EHIT classification system. The novel classification system affords standardization in reporting but also allows continued combined evaluation with the current body of literature. Recommendations codify the use of duplex ultrasound for the diagnosis of EHIT. Risk factor assessments and methods of prevention including mechanical prophylaxis, chemical prophylaxis, and ablation distance are discussed.

Treatment guidelines are tailored to the AVF EHIT class (ie, I, II, III, IV). Reference is made to the use of surveillance, antiplatelet therapy, and anticoagulants as deemed indicated, and the recommendations incorporate the use of the novel direct oral anticoagulants. Last, EHIT management as it relates to the great and small saphenous veins is discussed.

Acute Thrombotic Complication Post-Endovenous Ablation With Mobile Thrombus: A Case Study

Endovenous ablation is a common procedure performed on the superficial veins of the lower extremities to treat symptoms of venous insufficiency and varicose veins. While endovenous ablation is a minimally invasive procedure, patients may develop thrombotic complications including endovenous heat-induced thrombosis. Endovenous heat-induced thrombosis is a rare complication of thrombus extension from the superficial vein into or near the deep system postprocedure. In this case report, a female with a history of recent endovenous ablation presented to the emergency department with symptoms of a pulmonary embolism. Sonographic evaluation of the right lower extremity revealed extension of thrombus from the ablated superficial vein into the common femoral vein. Thrombus was also noted in the left lower extremity extending from the ablated superficial vein to approximately the saphenofemoral junction. While the left lower extremity was being interrogated, the thrombus was documented, via a cine clip, liberating from the occluded great saphenous vein. Further assessment utilizing computed tomography revealed bilateral pulmonary emboli. This unique case emphasizes the importance of sonographic evaluation post-endovenous ablation.