Ruth Fredericks

Valve reconstruction procedures for nonobstructive venous insufficiency: Rationale, techniques, and results in 107 procedures with two- to eight-year follow-up ☆

Among 211 limbs with nonobstructive chronic venous insufficiency, valve reflux of the deep system was the predominant (more than 70%) pathologic condition. Superficial venous or perforator incompetence when present invariably occurred in combination with valve reflux of the deep veins, suggesting that the latter is a common denominator for symptom production. Single level-single system reflux was only occasionally symptomatic (10%), whereas the incidence of single level-multisystem reflux (25%) and multilevel-multisystem reflux (65%) in symptomatic limbs was much higher. Our experience with 107 venous valve reconstructions with a 2- to 8-year follow-up is described. Different techniques of valve reconstruction employed are detailed. The most common pathologic feature is a redundant valve with malcoaptation probably of nonthrombotic origin. Valsalva foot venous pressure elevation is a useful hemodynamic technique for assessing surgical results. Valvuloplasty may be superior to other reconstruction techniques in relieving symptoms of stasis, including stasis ulceration.

Venous obstruction: An analysis of one hundred thirty-seven cases with hemodynamic, venographic, and clinical correlations*

One hundred thirty-seven limbs with venous obstruction were analyzed. The arm/foot venous pressure differential and reactive hyperemia tests were found to be useful techniques to diagnose and grade venous obstruction. Traditional techniques including venography and ambulatory venous pressure are inferior in this regard. The newer techniques have provided newer insights in venous obstruction which are detailed herein. The hand-held Doppler was surprisingly very sensitive in grade I as well as in more severe forms of obstruction. Neither anatomic locale of obstruction nor its extent determined hemodynamic severity. Extensive proximal lesions could be hemodynamically mild, and conversely distal crural obstructions and single segment lesions could be hemodynamically severe. Phlebographic appearance was a poor index of collateralization. The paradoxical venous pressure response to the reactive hyperemia test in grade IV obstruction was found to be due to suppression or delay of the reactive hyperemia response itself in the presence of severe venous obstruction. The pain of venous claudication may be related to this phenomenon. Skin ulceration in the presence of venous obstruction was related to the associated reflux rather than the hemodynamic severity of the obstruction itself. The Linton procedure was found to be useful in treating such skin ulcerations. After perforator disruption, obstruction did not become hemodynamically worse, but reflux as measured by the Valsalva test improved with ulcer healing. The improvement in reflux related to Valsalva offers for the first time a hemodynamic rationale for the Linton procedure.

Hemodynamic basis of stasis ulceration—A hypothesis

Approximately 25% of patients with stasis ulceration have normal or below normal ambulatory venous pressures. A reflux index was calculated by multiplying postexercise pressures by Valsalva-induced foot venous pressure elevation. In patients with stasis ulceration, reflux index was found to have an excellent negative predictive value with a clear discriminant line between normal limbs and those with ulcers. Increasing incidence of stasis ulceration was demonstrated with increasing reflux index value. Even when ambulatory venous pressure was within the normal range, the index was found to be abnormal in ulcerated limbs because Valsalva-induced foot venous pressure was elevated in these limbs. Conversely, some patients with stasis ulceration and normal Valsalva foot venous pressure elevation were found to have abnormal ambulatory venous pressure values, yielding an elevated reflux index. Preliminary analysis indicates that reflux index may be a better predictor of surgical outcome after valve reconstruction procedures than either ambulatory venous pressure or Valsalva-induced foot venous pressure elevation. The concept of reflux index is a hypothesis that attempts to explain inconsistencies observed in implicating ambulatory venous hypertension as the sole determinant of venous reflux.

Saphenectomy in the presence of chronic venous obstruction

BACKGROUND The results of saphenectomy in patients with morphologic and functional obstruction were compared with those in patients without obstruction. Excision of secondary saphenous varices associated with deep venous obstruction has long been considered contraindicated for fear of compromising its collateral contribution. Recent advances in accurate functional assessment of venous obstruction make it possible to test this concept. METHODS Saphenectomy was carried out in 51 limbs without morphologic or functional obstruction and 64 limbs with varying grades of venous obstruction. Significant deep venous obstruction on ascending venography was present in the latter group. Functional assessment of obstruction was based on the arm/foot venous pressure differential technique, outflow fraction measurements, and outflow resistance calculations. Valve reconstruction was carried out in conjunction with saphenectomy in 81% of cases. RESULTS Saphenectomy was clinically well tolerated in both groups, and there was no difference in outcome as measured by objective tests for obstruction; improvement in reflux and calf venous pump function was largely similar. Among seven limbs with severe preoperative venous obstruction (grade III or IV), five (70%) had significantly improved obstructive grading, presumably as a result of elimination of reflux flow. CONCLUSIONS The traditional admonition against removal of secondary varices should be reexamined. Saphenectomy may be indicated in postthrombotic syndrome with mixed obstruction/reflux. The procedure is clinically well tolerated and without malsequelae. Improvement in reflux parameters without significant worsening of objective measures of obstruction is documented in this group.

Lenalidomide stops progression of multifocal epithelioid hemangioendothelioma including intracranial disease

Epithelioid Hemangioendothelioma (EH) is a rare soft-tissue tumor which may present as an isolated tumor or can spread to affect internal organs. The course of EH varies, based on the tissue of origin. This case report describes a young woman who developed cutaneous EH with concurrent intracranial disease during pregnancy. After resection, the lesions returned. Even after several courses of chemotherapy and radiotherapy, the patient developed multifocal disease including pulmonary, skeletal, and liver disease. She now exhibits stable disease after approximately 6 years of therapy with lenalidomide.

Ambulatory Venous Hypertension: Component Analysis in 373 Limbs

Purpose: We studied factors contributing to ambulatory venous hypertension in patients with symptoms of chronic venous insufficiency in order to delineate the contribution of each to global venous hypertension. Methods: A total of 373 consecutive limbs with ambulatory venous hypertension were studied. Simultaneous ambulatory venous pressure and air plethysmography measurements allowed compliance calculations. With reactive hyperemia, maximal arterial inflow was measured. Air plethysmography provided calf venous pump capacitance and ejection fraction data. Reflux was quantified by a point system based on Duplex, venous filling index on airplethysmography (VFI-90), Valsalva foot venous pressure, and ambulatory venous pressure recovery time (VFT). Multiple regression analysis was used to model ambulatory venous pressure in terms of these variables. Results: Six major causes of ambulatory venous hypertension were identified and quantified: 1. reflux, 2. increased arterial inflow, 3. reduced venous capacitance, 4. poor ejection fraction, 5. poor compliance of the calf venous pump, and 6. a combination of factors. Of the total, 91% of the limbs had at least two of these factors, 57% had three factors, and 24% had four factors contributing to ambulatory venous hypertension. Reflux was present in 97% of limbs but was significant (VFT <15 seconds) in only 57%, suggesting that other factors were dominant in the remainder. Conclusion: Ambulatory venous hypertension is a multifactorial entity. Many of the contributing factors are interrelated in a complex fashion. Regression analysis indicates that even though reflux followed by arterial inflow and capacitance were important as single contributing factors, a combination of factors is more important than any single individual factor in the genesis of ambulatory venous hypertension. VFT was found to be superior to other measurements in quantifying global reflux.

Tube Collapse and Valve Closure in Ambulatory Venous Pressure Regulation: Studies with a Mechanical Model

Purpose: To determine the role of valve closure and column segmentation in ambulatory venous pressure regulation. Methods: Using a mechanical model consisting of a graduated adjustable valve and a collapsible tube, we studied the differential effects of valve closure and tube collapse on venous pressure regulation. By utilizing materials with differing wall properties for the infravalvular tube, the influence of wall property changes on tube function and pressure regulation was explored. Results: Valve closure, per se, does not cause venous pressure reduction. Collapse of the tube below the valve is the primary pressure regulatory mechanism. The nonlinear volume-pressure relationship that exists in infravalvular tubes confers significant buffering properties to the collapsible tube, which tends to retain a near-constant pressure for a wide range of ejection fractions, residual tube volumes, and valve leaks. Changes in tube wall property affect this buffering action, at both the low and high ends of the physiological venous pressure range. Conclusions: The valve and the infravalvular venous segment should be considered together in venous pressure regulation. Tube collapse of the segment below the valve is the primary pressure regulatory mechanism. An understanding of the hydrodynamic principles involved in pressure regulation derived from this model will provide the basis for construction of more complex models to explore clinical physiology and dysfunction.