Stationary Blood Particle Aggregates and Vein Valve Shape: A New Classification of Vein Damage

Abstract

By use of novel high-resolution ultrasound systems, valvular structures and low-flow microaggregates may be depicted today in a more detailed way. The existence of particle aggregations within a valve sinus that are neither sludge nor thrombus, detected by high-resolution ultrasound (American Venous Forum Servier Travel Award 2017), was recently reported. This consecutive study of 180 single-vein valves showing motion-resistant aggregates compares valve structures, cusp motility, and extent of aggregates, resulting in a new approach to vein damage classification. In 100 consecutive patients (68 female, 32 male; 42-64 years old) presenting with unilateral epifascial venous insufficiency, a total of 180 saphenous vein valves with motion-resistant aggregates were selected for closer high-resolution ultrasound analysis (14-16 MHz, peak up to 40 MHz; Vevo MD [SonoSite, Bothell, Wash]). Video recordings (manual three-dimensional scans) were provided for review and analysis by five experienced ultrasound investigators. Six different stages of valve changes could be determined. In stage 1, alteration of sinus hemodynamics (reduction of flushed sinus volume) was present in 102 of 180 cases (56.7%). In stage 2, restriction of cusp function due to aggregates while maintaining valve closure was seen in 64 cases (35.6%). Of 180 cases, 6 (3.3%) showed fixation of cusps (without visible motility) but yet without reflux (stage 3), whereas in 8 cases (4.5%), there was fixation of cusps causing diastolic gap and reflux (stage 4; Fig). Stages 5 and 6 were related to segments with significant reflux (>1000 ms, >10 cm/s), showing valve regression and finally loss of valve structures and aggregates. Permanent blood cell aggregates at the valve sinus seem to indicate successive stages of venous insufficiency, correlating with specific relations of sinus shape and flow. Analysis of valves and aggregates allows a new staging of vein damage and thus a more detailed determination of the individual history of disease with potential impact for early-stage treatment or prevention.