Gait and calf muscle endurance in patients with chronic venous insufficiency.

OBJECTIVE: To gain insight in gait and calf muscle endurance in patients with severe chronic venous insufficiency. METHODS: Fifteen patients with severe chronic venous insufficiency (healed or active ulcers) and 19 healthy controls were selected for this study. Subjects had to perform eight trials at preferred walking speed and eight trials at instructed walking speed (1.25 m/s) during which the gait parameters were recorded. The calf muscle endurance was tested by use of the heel-rise test. RESULTS: Patients had a significantly lower preferred walking speed (1.25 m/s +/- 0.31) compared with healthy controls (1.44 m/s +/- 0.0.15) (p = 0.039). During preferred walking speed patients had a wider base of support (p = 0.003), a bigger step time (p = 0.005), and a bigger stride time (p = 0.004) compared with healthy controls. At instructed walking speed only base of support was different between the two groups (p = 0.016). Patients had a significantly (p = 0.003) smaller number of heel rises (14.6 +/- 7.34), indicating decreased calf muscle endurance compared with controls (23.5 +/- 6.54). CONCLUSION: This study indicates a disturbed gait and decreased calf muscle endurance in patients with severe chronic venous insufficiency. The results of this study point to a possible role for gait and strength training in the rehabilitation process of patients with severe chronic venous insufficiency.

Evolution of deep venous thrombosis: a 2-year follow-up using duplex ultrasound scan and strain-gauge plethysmography.

OBJECTIVE: The development of the post-thrombotic syndrome (PTS) and recurrence of deep venous thrombosis (DVT) are not yet fully understood. The aim of the study was to identify factors that lead to the long-term complications of DVT. METHODS: In a 2-year prospective follow-up study, duplex scanning and strain-gauge plethysmography were used to evaluate DVT in relation to the development of long-term complications. Each of the 12 segments examined was assigned as a thrombosis score (TS). A total TS was calculated for each leg. Patent segments were assigned a TS = 0, noncompressible vein segments with flow TS = 1 and noncompressible vein segments without flow TS = 2. The degree of resolution of DVT and the incidence, timing, and outcome of further thrombotic events were measured during 24 months of follow-up. RESULTS: The study involved 86 legs with DVT. The 2-year follow-up was completed for 70 legs. Within 3 months, only 1% of the originally occluded proximal deep vein segments were still occluded. Between all time intervals, from month 12 to month 24, for example, thrombus regression continued in 36% of the legs and thrombus propagation continued in 27%. Multiple regression analysis revealed that an increase in age (P = .008) and proximal location of the original DVT (P = .05) was significantly related to thrombus propagation. Multiple regression analysis showed that the risk factors for clinical signs of PTS were a high venous outflow resistance after 1-month and 12-month follow-ups (P

Venous reflux has a limited effect on calf muscle pump dysfunction in post-thrombotic patients.

The purpose of the present study was to evaluate the relationship between calf muscle pump dysfunction (CMD) and the presence and location of valvular incompetence. Deep vein obstruction might influence CMD, and so venous outflow resistance (VOR) was measured. VOR and calf muscle pump function were measured in 81 patients, 7-13 years after venographically confirmed lower-extremity deep venous thrombosis. The supine venous pump function test (SVPT) measures CMD, and the VOR measures the presence of venous outflow obstructions, both with the use of strain-gauge plethysmography. Valvular incompetence was measured using duplex scanning in 16 vein segments of one leg. Venous reflux was measured in proximal veins using the Valsalva manoeuvre, and in the distal veins by distal manual compression with sudden release. Abnormal proximal venous reflux was defined as a reflux time of more than 1 s, and abnormal distal venous reflux as a reflux time of more than 0.5 s. No statistically significant relationship was found between the SVPT and either the location or the number of vein segments with reflux. Of the 81 patients, only nine still had an abnormally high VOR, and this VOR showed no relationship with the SVPT. In conclusion, venous reflux has a limited effect on CMD, as measured by the SVPT. The presence of a venous outflow obstruction did not significantly influence the SVPT. Duplex scanning and the SVPT are independent complementary tests for evaluating chronic venous insufficiency.

The postthrombotic syndrome in relation to venous hemodynamics, as measured by means of duplex scanning and strain-gauge plethysmography.

PURPOSE: Venous hemodynamics were evaluated in relation to the postthrombotic syndrome (PTS) 7 to 13 years after deep venous thrombosis (DVT). METHODS: The presence of flow, reflux, and compressibility of 1394 vein segments in 82 patients was assessed by means of duplex scanning. The venous outflow resistance was measured by means of strain-gauge plethysmography. The venous hemodynamics were related to the clinical severity of the PTS, characterized by the CEAP (clinical, etiologic, anatomic, pathophysiologic) classification. RESULTS: In patients with severe clinical symptoms of PTS, the prevalence of reflux was significantly higher. There was no relationship between the severity of the PTS and the noncompressibility or the combination of reflux and noncompressibility or an increased venous resistance. By means of multiple regression analysis with the variables of age, gender, reflux, and venous resistance, age and reflux were shown to be the main contributors to the severity of PTS. Significantly more patients (64%) with severe signs of PTS had a combination of deep and superficial reflux. In each of the traceable vein segments, the mean of the CEAP classification was calculated for the vein segments with and without reflux. In the proximal superficial femoral vein (P <.001), distal superficial femoral vein (P <.05), and popliteal vein (P <.05), a significantly higher mean CEAP classification was found in the veins with reflux, whereas in the distal, long, and short saphenous veins, no such relationship was found. CONCLUSION: Most patients with severe PTS had a combination of deep and superficial reflux. Reflux in the deep proximal veins contributes significantly to the PTS.

Venous duplex scanning of the leg: range, variability and reproducibility.

Despite the many studies on venous haemodynamics using duplex, only a few evaluated the normal values, variability and reproducibility. Therefore, the range and variability of venous diameter, compressibility, flow and reflux were measured. To obtain normal values, 42 healthy individuals (42 limbs, 714 vein segments) with no history of venous disease were scanned by duplex. To determine the reproducibility the intra-observer variability was measured in 11 healthy individuals (187 vein segments) and the inter-observer variability in 15 healthy individuals (255 vein segments) and 13 patients (169 vein segments) previously diagnosed with deep venous thrombosis. Of the 714 normal vein segments, 708 (99%) were traceable, including the crural veins. Of the traceable vein segments, 675 (95%) were compressible and in 696 (98%) flow was present. Of the 42 common femoral vein segments, in 25 (60%) the reflux duration exceeded 1.0 s, but in the other proximal vein segments the reflux duration was less than 1.0 s (95% confidence interval 3.0-10.0). With the exception of the distal long saphenous vein, in the distal vein segments the reflux duration was less than 0.5 s (95% confidence interval 3.5-8.2). The coefficient of variation of the diameter measurements ranged from 14 to 50% and that of the reflux measurements from 28 to 60%. The kappa-coefficient of the inter-observer variability in the classification of compressibility measurements in the patients was 0. 77 and that of the reflux measurements was 0.86. This study shows that almost all veins were compressible in healthy individuals, except the distal femoral veins. In healthy individuals the duration of reflux of the proximal veins was less than 1.0 s and in the distal veins it was less than 0.5 s. The inter-observer variability of the reflux and compressibility measurements in the patients was good.

Deep venous thrombosis: a prospective 3-month follow-up using duplex scanning and strain-gauge plethysmography.

1. The purpose of the study was to evaluate the degree of thrombus regression, development of valvular insufficiency, impaired calf muscle pump function and clinical symptoms after a period of acute deep venous thrombosis. 2. Seventy patients with acute deep venous thrombosis, diagnosed by duplex scanning or venography, received treatment with heparin and oral coumarin derivatives according to a standard protocol. All patients wore graduated compression stockings during the whole study period. Duplex scanning was performed at diagnosis and 1 and 3 months later to measure thrombus mass and reflux. The supine venous pump function test was used to assess calf muscle pump function. 3. Three months follow-up was completed in 60 patients. In total 218 (28%) out of 780 vein segments were initially thrombosed and 134 (17%) could not be traced. A statistically significant reduction of thrombus mass was recorded throughout the study period. Total resolution of thrombosis in all vein segments occurred in 25% of the patients within 1 month and in 40% in 3 months. There was no difference in regression between the various proximal vein segments. Distal segments showed more regression than proximal segments. Reflux occurred in 27% of the initially thrombosed veins and in 15% of the patent veins. Patients who showed total resolution after 1 month had a significantly higher calf muscle pump function than patients without total resolution (70%pf vs 61%pf, P < 0.05). Patients with reflux in two or more segments had a significantly lower calf muscle pump function than patients with reflux in less than two segments (58%pf vs 69%pf, P < 0.05). 4. Using duplex scanning and the supine venous pump function test 3 months after an acute deep venous thrombosis, overall haemodynamic abnormalities and local site of valve incompetence could readily be identified. Patients with haemodynamic abnormalities might be at risk to develop the post-thrombotic syndrome. There was no difference in thrombus regression between the various proximal vein segments. Reflux was significantly more often seen in initially thrombosed veins. Thirty-five percent of the patients developed an abnormal calf muscle pump function after 3 months. Patients with early resolution of thrombus had a higher calf muscle pump function after 3 months.

Duplex ultrasound in the hemodynamic evaluation of the late sequelae of deep venous thrombosis.

PURPOSE: The use of duplex ultrasound scanning to evaluate the hemodynamic outcome of deep venous thrombosis 7 to 13 years after the original diagnosis. METHODS: Duplex ultrasound was used to re-examine 1212 segments of vein from 72 patients (49 men, 23 women) with deep venous thrombosis previously diagnosed by means of phlebography to detect reflux and obstruction and evaluate flow; 611 segments were initially thrombosed and 601 segments were open. To define reflux, reversed flow in 31 healthy persons was measured. RESULTS: In a review of all veins of the 72 patients, 8 patients (11%) had completely normal duplex results in all veins, 33 (46%) had reflux, 6 (8%) had at least one noncompressible vein segment, and 25 (35%) had a combination of both. In the proximal vein segments without initial thrombosis a higher percentage was normal (73%) than in segments with initial thrombosis (46%). There was a significantly higher frequency of reflux (46%, p = 0.05) and noncompressibility (12%, p < 0.01) in initially thrombosed proximal vein segments than in vein segments without initial thrombosis (reflux 25%, noncompressibility 3%). Distal to the knee 125 (17%) of 720 vein segments were not traceable. Significantly more initially thrombosed vein segments were not traceable (p < 0.01). In distal vein segments there was no significant difference in reflux (7% versus 5%) and noncompressibility (10% versus 5%) between vein segments with and without initial thrombosis. Flow was present in 99% of the 611 previously thrombosed proximal and distal segments. CONCLUSIONS: Most patients with deep venous thrombosis still had venous abnormalities 7 to 13 years after the initial diagnosis. The most common abnormality was reflux. Significantly more abnormalities were found in initially thrombosed segments. The abnormalities were found in the proximal vein segments and in the distal vein segments, although less frequently in the latter.

Doppler spectrum analysis versus direct femoral artery pressure measurement for rapid assessment of aortoiliac obstruction.

Adequate patient selection is required to limit the clinical workload and improve the cost-effectiveness of noninvasive hemodynamic evaluation of the aortoiliac system. In a prospective blinded fashion the traditional invasive technique of direct femoral artery pressure measurements and the computerized Doppler spectrum analysis of blood flow velocities in the common femoral artery were studied. Both tests for rapid assessment of aortoiliac obstruction were compared with duplex ultrasonographic imaging, using a peak systolic velocity ratio of 2.5 to demonstrate stenoses of 50% or more. In a series of 17 consecutive patients (34 aortoiliac segments) with suspected aortoiliac obstructive disease, a good level of agreement (kappa = 0.6) was found for both methods when compared with duplex scanning. Analysis of deviations from the duplex registrations indicated an overestimation of the pathologic cases using femoral artery pressure measurements and an underestimation using Doppler spectrum analysis of blood flow velocities in the common femoral artery. Both methods were well tolerated, but femoral artery pressure measurements had a higher technical failure rate. Because of its noninvasive character and its feasibility the Doppler technique is preferred for the selection of patients for more extensive duplex sonographic investigation.

Clinical and haemodynamic sequelae of deep venous thrombosis: retrospective evaluation after 7-13 years.

1. In contrast to the extensive documentation on diagnosis and treatment of deep venous thrombosis (DVT), information about long-term complications, like the post-thrombotic syndrome (PTS), is scarce. Most studies report on clinical examination only, whereas adequate haemodynamic investigation is lacking. Therefore 81 patients with venographically confirmed lower extremity DVT were clinically and haemodynamically reexamined 7-13 years after DVT (mean 10 years) to assess PTS. Interest was focused on the relation between clinical and haemodynamic PTS and the relation between location of the initial DVT and incidence of PTS. 2. Clinical signs and symptoms of PTS were classified according to the latest consensus of the international consensus committee on chronic venous disease. Non-invasive venous vascular laboratory tests were performed to assess the venous outflow resistance and calf muscle pump function (CMP). CMP was determined by the supine venous pump function test (SVPT). 3. Clinically only 20 of 81 patients (25%) were asymptomatic, 34 (42%) had mild PTS (class 1-3), 25 (31%) moderate PTS (class 4) and 2 (2%) severe PTS (class 5-6); 57% had an abnormal CMP. Both the severity of clinical symptoms and the haemodynamic abnormalities were related to the location of the initial thrombus. Of the patients with distal DVT 11% developed moderate clinical PTS and 39% developed an abnormal CMP. CMP and difference in CMP between post-thrombotic and non-thrombotic leg were significantly related to the different classes of PTS. 4. This study indicates that 7-13 years after DVT 31% of the patients had moderate and 2% had severe clinical PTS, while 57% of the patients had abnormal haemodynamic findings (both related to the initial site of the thrombosis). Secondly, it reveals that the risk of PTS after distal DVT is not negligible, which causes concern about not diagnosing and treating patients with distal DVT. Thirdly, we have demonstrated that a functional test, such as the SVPT, is a sensitive test to assess post-thrombotic damage. Therefore its use as a screening tool after a period of DVT should be investigated to select patients at risk of PTS.