Results and lessons to be learned from a waiting list initiative.

Varicose veins are a major and increasing burden on the health service with waiting lists growing in the majority of units. Most successive Governments have funded waiting list initiatives to deal with this problem. We report the results of a one year varicose vein waiting list initiative which dealt with a total of 1104 patients. A standard triage regime was established. Two hundred and eighty five patients were removed from the waiting list due to failure to attend, surgery performed elsewhere, medically unfit or no longer wishing to have surgery. There were 63 late cancellations and 23 operations were cancelled following admission due to unrelated medical complications. Planned operating lists worked well and complications were uncommon. Several important lessons were learnt during this initiative and recommendations are made with regard to the optimal method of dealing with the problem of varicose veins.

Asymptomatic carotid stenosis: a benign lesion?

Recent reports of the risk of asymptomatic carotid stenosis have been compromised by flawed patient selection or the performance of a large number of carotid endarterectomies during follow-up. We report the natural history of a randomly selected group of asymptomatic patients (n = 188; 114 males and 74 females) with documented carotid artery disease who were prospectively followed without intervention for up to 8 years. Risk factors included ischaemic heart disease in 17%, diabetes in 10%, hypertension in 46% and 88% were smokers. The degree of internal carotid stenosis was classified by duplex scanning and a total of 259 vessels had evidence of atherosclerosis. Study end-points included TIA, CVA and death. At mean follow-up of 4 years 3% of the 96 patients with internal carotid artery stenosis of less than 50% had died and 2% suffered a stroke. Six per cent of patients with a stenosis of 50-79% had died and 4% and 2% had suffered a CVA and TIA, respectively. In the 59 patients with greater than 80% stenosis 7% had suffered a TIA and an additional 7% a CVA, while 2% had died. None of the patients suffering a stroke had an antecedent TIA. Though the incidence of ischaemic events is significantly higher in patients with greater than 80% stenosis the incidence of unheralded stroke remains low. We therefore continue to recommend a conservative approach to the management of asymptomatic carotid stenosis.

Can pre-operative duplex scanning replace pre-operative short saphenous venography as an aid to localizing the sapheno-popliteal junction?

The accuracy of Duplex ultrasound scanning in locating the sepheno-popliteal junction (SPJ) was assessed by comparison with clinical examination and short saphenous venography. Twenty-three legs with varicosities of the short saphenous system had their SPJ located by Duplex scanning and marked pre-operatively. Varicography was performed on all patients. Clinical examination localised the junction to within 2 cm in 8/23 (37%) compared to 16/23 (74%) for Duplex ultrasonography and 21/23 (93%) venography. Ihis study shows that Duplex ultrasonography while more accurate than clinical evaluation, should not replace venography in the pre-operative localisation of the SPJ.

Duplex ultrasonography and selection of patients for carotid endarterectomy: plaque morphology or luminal narrowing?

Percentage of carotid stenosis and plaque morphology as determined by duplex scanning were correlated with symptoms and CT evidence of infarction in 108 patients. Severity of carotid stenosis less than 49% or greater than 50% narrowing was not associated with an increased risk of ipsilateral symptoms or CT infarction. However, a heterogeneous plaque appearance, suggesting intraplaque hemorrhage, did correlate with ipsilateral cerebral symptoms. Heterogeneous plaque appearance may be a more reliable indication for carotid endarterectomy than a hemodynamically significant stenosis.

Assessment of arterial disease using digital systolic pressure measurement.

Digital systolic pressure measurements were made on 140 big toes using a photoplethysmographic technique before and after extrinsic heating of the foot. Most patients with apparent, critically ischemic feet demonstrated vasomotor activity, suggesting that much of the microcirculation of the foot was in fact intact. Significantly, nine of 21 feet which would have fallen into a critically ischemic category were recategorized after heating into a less severe group. These data confirm the value of toe pressure measurements in the assessment of severe ischemia but show that adequate foot vasodilation is essential to allow accurate conclusions to be drawn and to allow meaningful interpretation of results.

Duplex scanning for noninvasive assessment of both carotid luminal diameter and atheromatous plaque morphology.

The value of Duplex scanning in 50 consecutive patients with symptomatic carotid stenosis was evaluated. Compared with contrast arteriography, the sensitivity of Duplex scanning, for a greater than 50% internal carotid diameter reduction, was 90% (66/73) with a specificity of 96% (26/27). The overall agreement between Duplex and contrast arteriography as measured by the Kappa value was K = 0.561. One of the 13 arteries felt to be occluded on Duplex scanning was radiologically found to be patent. Excluding the six normal and 13 occluded arteries, 81 carotid plaques were defined as either heterogeneous, suggestive of intraplaque hemorrhage or as homogeneous. Twenty-four of the 32 asymptomatic cerebral hemispheres were associated with ipsilateral homogeneous plaques, while 30 of the 49 symptomatic hemispheres had heterogeneous plaques in the ipsilateral carotid, (p less than 0.001). This study confirms the accuracy of duplex scanning in detecting internal carotid stenosis as well as in identifying plaques which are morphologically heterogeneous and more likely to be associated with ipsilateral cerebral hemispheric symptoms.