Post-thrombotic syndrome after upper extremity deep vein thrombosis: An international Delphi consensus study

Primary deep vein thrombosis of the upper extremity (UEDVT) is a rare condition but up to 60% of patients may develop post-thrombotic syndrome in the upper extremity (UE-PTS) with significant morbidity and decreased quality of life. However, there is no universally accepted method to diagnose and classify UE-PTS, hampering scientific research on UEDVT treatment. Through this international Delphi consensus study we aimed to determine what a clinical score for diagnosing UE-PTS should entail.

An online focus group survey among 20 patients treated for UEDVT was performed to provide clinical parameters before the start of a four round electronic Delphi consensus study among 25 international experts. The CREDES recommendations on Conducting and Reporting Delphi Studies were applied. Open text questions, multiple selection questions, and 9-point Likert scales were used. Consensus was set at 70% agreement.

After four rounds, agreement was reached on a composite score of five symptoms and three clinical signs, combined with a functional disability score. The signs and symptom will each be scored on a severity scale of 0-3 and the total score expressed as an ordinal variable; no/mild/moderate/or severe PTS. The functional disability portion measures the impact of the signs and symptoms on the functionality of the patient's arm.

Consensus was reached on a composite score of signs and symptoms of UE-PTS combined with a functional disability score. Clinical validation of the UE-PTS score in a large patient cohort is mandatory to facilitate application in future research.