T. Hartshorne

Subintimal angioplasty of femoropopliteal artery occlusions: The long-term results*

The technique of subintimal angioplasty has been attempted on 200 consecutive femoropopliteal artery occlusions of median (range) length 11 (2-37) cm. The principle of the technique is to traverse the occlusion in the subintimal plane and recanalise by inflating the angioplasty balloon within the subintimal space. The technical success rate was 159/200 (80%) and was not significantly different for occlusions < 10 cm (81%, n = 73), 11-20 cm (83%, n = 63) or > 20 cm (68%, n = 23), p = 0.20. There were no deaths nor limb loss resulting from the procedure. The median (range) ankle-brachial pressure index increased from 0.61 (0.21-1.0) preangioplasty to 0.90 (0.26-1.50) postangioplasty. The actuarial haemodynamic patencies of technically successful procedures at 12 and 36 months were 71% and 58% respectively, the symptomatic patencies were 73% and 61%. A multiple regression analysis showed that smoking multiplied the risk of reocclusion by 2.70 (p < 0.001), each additional run-off vessel reduced the risk by 0.54 (p < 0.001) and the risk increased by 1.73 (p = 0.020) for every 10 cm of occlusion length. In conclusion, the technical success rate (80%) of subintimal angioplasty for femoropopliteal occlusions is unrelated to occlusion length and for all procedures, including technical failures, cumulative symptomatic and haemodynamic patencies of 46 and 48% can be achieved at 3 years. The factors influencing long-term patency were smoking, the number of calf run-off vessels and occlusion length.

Joint Recommendations for Reporting Carotid Ultrasound Investigations in the United Kingdom

At present in the United Kingdom a number of different criteria are used to grade disease in carotid ultrasound investigations. One main cause of this has been the difference in the method of grading angiograms used in the NASCET and ECST large carotid surgery trials. It is desirable that all centres reporting carotid ultrasound investigations report to the same standard. This paper presents recommendations for the reporting of ultrasound investigations of the extra cranial arteries produced by a Joint Working Group formed between the Vascular Society of Great Britain and Ireland, and the Society for Vascular Technology of Great Britain and Ireland. The recommended criteria are based on the NASCET method of grading carotid bulb disease. Key recommendations include recording peak systolic velocity (PSV) and end-diastolic velocity (EDV) in both internal and distal common carotid arteries; measuring all velocities at a Doppler angle of 45-60 degrees; the use of internal carotid PSV of >1.25 ms(-1) and >2.3 ms(-1) and a Peak Systolic Velocity Ratio of >2 and >4 to indicate >50% and >70% stenosis respectively; and the use of the St Marys Ratio to grade >50% stenoses in deciles. General recommendations are also given for the acquisition, interpretation and reporting of the data.

SUBINTIMAL ANGIOPLASTY OF INFRAPOPLITEAL OCCLUSIONS IN CRITICALLY ISCHAEMIC LIMBS

OBJECTIVE To review the outcome of subintimal angioplasty of infrapopliteal artery occlusions in critically ischaemic limbs. DESIGN Retrospective review. MATERIALS Twenty-eight consecutive limbs with critical ischaemia that had undergone subintimal angioplasty of infrapopliteal occlusions. RESULTS There were 32 infrapopliteal artery occlusions in 28 critically ischaemic limbs in 27 patients. The median (range) patient age was 81 (48-88) years. Seventeen limbs (61%) were ulcerated, seven (25%) were gangrenous and four (14%) had rest pain only. Twenty-five (89%) procedures were to a single calf vessel, and three (11%) procedures were to multiple calf vessels. The median (range) length of the occlusions was 7 (2-30) cm. The initial technical success rate was 27/32 (84%). There were three minor complications--one groin haematoma, one vessel perforation and one distal embolus. There were no limbs lost as a result of the procedure itself and the 30-day mortality was zero. The 12-month actuarial haemodynamic and symptomatic patencies (including initial failures) were 53% and 56%, respectively. The 12-month limb salvage rate was 85% and patient survival was 81%. CONCLUSION We conclude that subintimal angioplasty in patients with infrapopliteal artery occlusions and critical ischaemia is safe, effective, and offers a low-risk alternative to distal reconstructive surgery.

Ultrasound Measurement of Aortic Diameter in a National Screening Programme

OBJECTIVE Currently there is no universally accepted standard for ultrasound measurement of abdominal aortic aneurysm (AAA). The aim was to investigate the reliability and reproducibility of inner to inner (ITI) versus outer to outer (OTO) ultrasound measurement of AAA diameter. METHODS A prospective study design was used to collect 60 random images of aorta (1.4-7.1 cm). Inner and outer wall diameter measurements were then performed by 13 qualified AAA screening technicians and 11 vascular sonographers. RESULTS The mean (range) diameter for all 60 aortas by ITI was 3.91 cm (1.39-6.80) and by OTO was 4.18 cm (1.63-7.09), a significant mean difference of 0.27 cm (95% CI: 0.23-0.32 cm). The reproducibility coefficients for differences between technicians were 0.30 cm (95% CI: 0.24-0.36) for ITI and 0.42 cm (95% CI: 0.35-0.49) for OTO indicating significantly better repeatability using ITI. Finally, 15 images were measured twice in random order by all screeners and sonographers. For AAAs > 5 cm, repeatability was significantly better with ITI than OTO (0.14 vs. 0.21; p = 0.016). CONCLUSION There was the expected difference in AAA diameter between the two methods (0.27 cm). However, ITI wall method was measurably more reproducible.

A prospective comparison of lower limb colour-coded duplex scanning with arteriography

OBJECTIVE To compare the diagnostic value of colour Duplex scanning with arteriography for the detection of arterial disease of the aortoiliac arteries, femoropopliteal arteries and the origins of the tibial vessels. DESIGN Prospective, semi-blind study. SETTING Vascular laboratory and radiology department, University Hospital. METHODS A total of 1658 arterial segments in 148 limbs were studied both by colour Duplex scanning and digital subtraction arteriography. Individual arterial segments were classified on the basis of peak systolic velocity ratios < 2.0, > or = 2.0 or an absent Doppler signal, as 0-49%, 50-99% diameter reduced, or occluded. The same arterial segments were similarly classified on the basis of arteriography and the two modalities were compared using a Kappa (k) analysis. RESULTS The overall agreement between arteriography and colour-coded Duplex was kappa = 0.74 (95% CI, 0.70-0.78), this indicates substantial agreement. Kappa values (95% CI) from the aortoiliac, femoropopliteal and the origins of the infrapopliteal arteries were kappa = 0.59 (0.49-0.73; moderate agreement), kappa = 0.80 (0.76-0.84; substantial agreement) and kappa = 0.48 (0.35-0.61; moderate agreement) respectively. CONCLUSIONS We conclude that there is substantial agreement between colour-coded Duplex and arteriography of the lower limbs, and that the ability of colour-coded Duplex to plan and guide lower limb vascular interventions requires investigation.

Unstable carotid plaques: Preoperative identification and association with intraoperative embolisation detected by transcranial doppler

OBJECTIVES To investigate whether unstable carotid plaque characteristics, as determined by preoperative colour Duplex ultrasonography (CDU) and postoperative histological examination, were associated with particulate embolisation, detected by transcranial Doppler (TCD), during the initial dissection of the carotid bifurcation during carotid endarterectomy(CEA). DESIGN A prospective, consecutive study was undertaken of 50 patients undergoing carotid endarterectomy(CEA). SETTING Leicester Royal Infirmary, Leicester, U.K. MATERIALS Carotid plaques were assessed preoperatively using CDU. Intraoperative TCD monitoring of the ipsilateral middle cerebral artery was performed using a Scimed 2MHz TCD. Carotid plaques removed at operation were processed histologically and multiple sections assessed microscopically. CHIEF OUTCOME MEASURES Plaque composition was classified ultrasonically and histologically according to the Gray-Weale classification and plaque surface characteristics were graded according to a five point classification. TCD detected emboli were identified and counted during the initial dissection of the artery. MAIN RESULTS Particulate embolisation occurred in nine patients. Histologically, embolisation was associated with ulcerated plaque in three cases and ulcerated plaque with associated thrombus in six cases (p = 0.0005). However, the ability of CDU to positively predict embolisation based on the correct identification of an unstable plaque surface was only 25%. CONCLUSIONS Embolisation during dissection is strongly associated with ulcerated plaque with associated thrombus. CDU is unable to reliably identify these characteristics preoperatively. Intraoperative TCD monitoring can detect potentially harmful embolisation during this stage enabling surgical technique to be modified appropriately.

Can lower limb vascular reconstruction be based on colour duplex imaging alone

OBJECTIVES To determine the safety and efficacy of Duplex scanning as the only imaging modality prior to lower limb vascular reconstruction. DESIGN Retrospective review. SETTING A single university vascular unit. PATIENTS AND METHODS Review of all lower limb vascular reconstructions over a 2 year period. RESULTS Eighty-five limbs underwent vascular reconstruction based on colour Duplex alone. A wide range of revascularising operations were performed, including 29 cases of infragenicular reconstruction. In the latter cases, the findings of Duplex scanning were confirmed by on table pre-reconstruction angiography in 28 cases and the graft occlusion rate in the first month was 14%. There were no postoperative complications that could be attributed to a failure of preoperative Duplex imaging. CONCLUSION Vascular reconstruction can be undertaken safely in patients with lower limb arterial disease on the basis of Duplex scanning alone.

The Role of Pulse-generated Run-off, Doppler Ultrasound and Conventional Arteriography in the Assessment of Patients Prior to Femorocrural Bypass Grafting

One of the most important prerequisites prior to femorocrural bypass is the identification of a patent calf vessel. To determine the ability of three preoperative investigations to demonstrate patent distal vessels we compared preoperative conventional arteriography, Doppler ultrasound measurement of ankle systolic pressure (ASP) and pulse generated run-off (PGR). PGR and ASP both identified significantly more calf vessels than did preoperative conventional arteriography. However, only PGR had the ability to distinguish those vessels suitable for bypass grafting from those unsuitable for grafting. These results demonstrate that PGR is the investigation of choice prior to femorocrural bypass.

The effect of adjacent segment disease on the accuracy of colour duplex scanning for the diagnosis of lower limb arterial disease

OBJECTIVE To assess the effect of multisegment disease upon the accuracy of lower limb colour Duplex scanning. DESIGN Prospective, semi-blind study. SETTING Vascular Laboratory and Radiology Department, University Hospital. METHODS A total of 148 limbs (1106 individual arterial segments) were examined from the distal aorta to the origins of the tibial arteries by colour-coded Duplex and arteriography. Individual segments were graded as 0-49%, 50-99% diameter reduced or occluded on the basis of peak systolic velocity ratios < 2.0, > or = 2.0 or an absent Doppler signal, and compared with similarly graded segments from blinded angiographic studies. The agreement (Kappa analysis) between Duplex and arteriography in segments adjacent to at least one proximal or distal > or = 50% diameter reducing lesion was then compared to the agreement between segments free of adjacent disease. RESULTS For isolated areas of disease, the kappa value (95% confidence interval) of agreement between Duplex ultrasonography and arteriography was 0.63 (0.53-0.73) and in the presence of neighbouring disease the value was 0.78 (0.73-0.83). CONCLUSION We conclude therefore that providing appropriate criteria are used, Duplex assessment of lower limb arterial disease is not adversely affected by adjacent disease.

Popliteal entrapment syndrome: Misdiagnosed as a compartment syndrome

We report a case of popliteal artery entrapment syndrome which was originally diagnosed as a chronic compartment syndrome. The relative occurrence of the two conditions and their very similar symptoms explain the misdiagnosis. The diagnostic methods and surgical treatment for both conditions are discussed and suggestions are made as to possible non-invasive screening methods.