Pol Arch Intern Med. 2023 Aug 7:16543. doi: 10.20452/pamw.16543. Online ahead of print.
Isolated distal deep vein thrombosis (IDDVT) is a frequent manifestation of venous thromboembolism (VTE), accounting for up to 50% of lower-extremity DVTs. Compared with proximal DVT, IDDVT is more frequently associated with transient risk factors and less often occurs as unprovoked or in the presence of permanent risk factors. IDDVT generally carries a significantly lower risk of proximal extension, post-thrombotic syndrome and recurrence than proximal DVT. Nevertheless, some patient subgroups such as those with active cancer, other predisposing permanent risk factors, prior VTE, unprovoked IDDVT, persistently restricted mobility, and trifurcation or bilateral involvement exhibit a non-negligible recurrence risk. Unlike proximal DVT, the optimal therapeutic management of IDDVT remains uncertain. In clinical practice, the vast majority of IDDVT patients are managed with anticoagulation rather than surveillance serial compression ultrasonography, which tends to be reserved to subjects at high bleeding risk. Available data seem to favor anticoagulant therapy over no anticoagulation, thanks to a significant reduction in the risk for proximal extension and recurrence, without increased bleeding risk. Recent results of the RIDTS randomized clinical trial with rivaroxaban further support the use of anticoagulant therapy for 3 months over shorter durations (e.g. 6 weeks or less). In this review, we offer an updated overview on the epidemiology, risk factors, and clinical course of IDDVT, with a focus on the therapeutic management in light of current guideline recommendations and most recent evidence. We also present real-life clinical cases of IDDVT with proposed therapeutic approaches, and highlight major challenges and gaps in this field.