Clinical relevance of symptomatic superficial-vein thrombosis extension: lessons from the CALISTO study

Abstract

Key Points• Symptomatic extensions, whether or not reaching the SFJ, are common complications of SVT.• Their frequency and associated risk of venous thromboembolic complications and medical resource consumption are reduced by fondaparinux.The clinical relevance of symptomatic extension of spontaneous, acute, symptomatic, lowerlimb superficial-vein thrombosis (SVT) is debated. We performed a post hoc analysis of a double-blind trial comparing fondaparinux with placebo. The main study outcome was SVT extension by day 77, whether to £3 cm or >3 cm from the sapheno-femoral junction (SFJ). All events were objectively confirmed and validated by an adjudication committee. With placebo (n 5 1500), symptomatic SVT extension to £3 cm or >3 cm from the SFJ occurred in 54 (3.6%) and 56 (3.7%) patients, respectively, inducing comparable medical resource consumption (eg, anticoagulant drugs and SFJ ligation); subsequent deep-vein thrombosis or pulmonary embolism occurred in 9.3% (5/54) and 8.9% (5/56) of patients, respectively. Fondaparinux was associated with lower incidences of SVT extension to £3 cm (0.3%; 5/1502; P < .001) and >3 cm (0.8%; 12/1502; P < .001) from the SFJ and reduced related use of medical resources; no subsequent deep-vein thrombosis or pulmonary embolism was observed in fondaparinux patients. Thus, symptomatic extensions are common SVT complications and, whether or not reaching the SFJ, are associated with a significant risk of venous thromboembolic complications and medical resource consumption, all reduced by fondaparinux. This trial was registered at www.clinicaltrials.gov: NCT00443053. (Blood. 2013;122(10):1724-1729

Annual diagnosis rate of superficial vein thrombosis of the lower limbs: the STEPH community‐based study

“…These results are in agreement with a recently published post-hoc analysis of 1500 placebo-treated patients included in a large randomized trial, suggesting that extension per se might be an index of SVT severity [18]. In our view, these findings argue that SVT is not a benign disease and support systematic recourse to compression ultrasonography as soon as it is suspected, even in patients seen in the primary care setting.…”

The risk of venous thrombosis in individuals with a history of superficial vein thrombosis and acquired venous thrombotic risk factors

“…by guest www.bloodjournal.org From self-reported question in a questionnaire, and that the location or length of SVT was not asked for. Therefore, it was not possible to take the length or extension of the SVT, which may be associated with the risk of venous thrombosis, 12 into account, or to ascertain whether our results apply equally to patients with SVT of the leg and patients with SVT in other anatomic locations.…”

Risk of venous and arterial thrombotic events in patients diagnosed with superficial vein thrombosis: a nationwide cohort study

“…An alternative explanation is a direct relation in which DVT/PE results from SVT. Considering that we adjusted for the most common and strongest risk factors for VTE, and in light of the clinical course of SVT, 22 the latter mechanism is likely largely responsible for our findings.…”