The additional value of intraoperative angiography in infragenicular reconstruction

Gadolinium-enhanced MR Angiography as First-Line Preoperative Imaging in High-Risk Patients with Lower Limb Ischemia

PURPOSE

To assess the clinical relevance of gadolinium-enhanced MR angiography (Gd-MRA) as the first-line angiographic examination for planning lower limb revascularization in patients at high risk of complications after contrast arteriography (CA).

METHOD

Forty-five consecutive patients at high risk of post-CA complications because of chronic renal insufficiency, diabetes mellitus, advanced age, or the need for brachial artery catheterization or graft puncture had Gd-MRA as first-line angiography before a surgical or endovascular procedure for lower limb ischemia.

RESULTS

After Gd-MRA, 59 procedures were performed, including 38 surgical reconstructions, 17 endovascular procedures, and four amputations. Complementary CA was only required in seven patients for whom a below-knee bypass was planned. Cumulative patency rates at 1 and 24 months were, respectively, 91% and 91% for suprainguinal bypasses, 100% and 92% for infrainguinal above-knee bypasses, 80% and 57% for below-knee bypasses, and 92% and 76% for iliofemoral angioplasties. After 24 months of follow-up, limb salvage, amputation, and mortality rates were, respectively, 86%, 3.5%, and 7% for stage II ischemia and 48%, 11%, and 30% for stages III and IV.

CONCLUSION

Gd-MRA can be proposed for first-line preoperative imaging in the management of lower limb ischemia for patients at high risk and permits the selective use of CA as a second-line examination if a below-knee bypass is required.

Durability of the dorsalis pedis artery reconstruction in diabetics and nondiabetics: is there a difference?

Originally thought to be a disadvantaged outflow source, the dorsalis pedis artery is associated with excellent patency and limb salvage in the diabetic population. The aim of this study was to demonstrate that the dorsalis pedis artery is as durable in nondiabetics as in their diabetic counterparts. During a 21-year period from 1979 to 1999, 299 long lower limb bypasses to the dorsalis pedis artery were performed at our institution. Patient data and outcomes were reviewed from the vascular registry. Statistical analysis and patency rates were compared using chi-squared and log-rank analysis. This study confirms that the dorsalis pedis can be used as an outflow source with durability that is comparable in both diabetics and nondiabetics. No significant difference exists in morbidity, mortality and patency rates. In the nondiabetic, when the dorsalis pedis is the only patent distal vessel, amputation can be avoided if one considers this a suitable option as an outflow source.

Interobserver Variation in Interpretation of Arteriography and Management of Severe Lower Leg Arterial Disease

OBJECTIVE

arteriography is the reference standard for the assessment of the lower leg arteries in patients with severe lower limb ischaemia. Interobserver variation in arteriography interpretation may cause disparities with non-invasive imaging modalities. We determined interobserver variation in lower leg artery assessment with intra-arterial digital subtraction angiography (IaDSA) and subsequent patient management.

MATERIALS

iaDSA studies of patients evaluated for severe claudication (n =5) or critical ischaemia ( n =43).

METHODS

arteriograms were independently judged by four observers. The popliteal and tibial arteries were graded as fully patent, severely diseased, occluded or non-diagnostic. The dorsalis pedis, common and deep plantar artery were graded as directly, indirectly or not filling the pedal arch or non-diagnostic. Agreement on grading arteries was expressed as kappa-values. Treatment plans (conservative, PTA, surgery, amputation, non-diagnostic) proposed by each observer based on clinical information and iaDSA were compared.

RESULTS

the rate of non-diagnostic judgements ranged from 1% in the popliteal to 22% in the pedal arteries. Overall agreement was good for grading the popliteal arteries (kappa=0.64), moderate for the tibial (kappa=0.47--0.54) and fair for the pedal arteries (kappa=0.39). Agreement was good to excellent for grading occluded or fully patent popliteal and tibial artery segments, and fair to moderate for grading severe disease. In 57% of cases at least 3 observers proposed identical treatment, which indicates fair overall agreement (kappa=0.33).

CONCLUSION

interobserver agreement on iaDSA is good to determine occluded or fully patent popliteal or tibial arteries, but not for severe disease. This should be taken into account when other diagnostic modalities are compared with iaDSA. Evaluation of diagnostic modalities as concordance in treatment plans is flawed by interindividual variation.

Optimized diagnostic angiography in high-risk patients with severe peripheral vascular disease

Conventional arteriography remains the usual method for preoperative assessment of severe peripheral vascular disease (PVD). Unfortunately, many peripheral arteriograms are still performed with a suboptimal technique, which can cause significant diagnostic errors in patients with severe PVD. A suboptimal technique may be due to poor collimation (causing incorrect exposure and incorrect gray scale), excessive patient-film distance (magnification unsharpness), inadequate volume or density of contrast material, poor contrast resolution (screen-film arteriography), nonselective injection, patient movement, and pressure from restraints or incorrect patient position (failure to profile lesions, pseudo-occlusion from external pressure or plantar flexion). The technique of selective digital subtraction arteriography (DSA) allows one to avoid these errors. The superior contrast resolution of DSA allows use of lower concentrations of contrast material. Selective injection into the external iliac artery allows proper positioning and improves image quality. Demonstration of distal vessels is best achieved by using biplane arteriography. For patients with severe resting ischemia, especially those with diabetes, high-quality selective DSA is essential to ensure that all distal vessels suitable for distal bypass grafting are identified. When properly performed, selective DSA remains the investigation of choice for reliably demonstrating arterial anatomy in high-risk patients with severe PVD.

Can cruropedal colour duplex scanning and pulse generated run-off replace angiography in candidates for distal bypass surgery

PURPOSE

To compare the diagnostic accuracy of duplex scanning (DS) and pulse generated run-off (PGR) with ia-DSA for the assessment of cruropedal outflow and explore the reliability of clinical decision making based on a work-up with DS/PGR in candidates for peripheral bypass surgery.

METHODS

Popliteal, crural and pedal arteries were evaluated independently with DS and ia-DSA in 126 limbs of 120 consecutive patients for claudication (16%) or critical ischaemia (84%). Arterial segments were graded with DS and ia-DSA as normal, stenosed, or occluded and compared using weighted kappa (kappa) analysis. PGR was used to select the best crural artery for bypass. Proposed management based on DS/PGR and, if applicable, anastomosis site were compared to definitive treatment based on ia-DSA.

RESULTS

Overall agreement between DS and ia-DSA for popliteal and crural arteries was moderate (kappa 0.51, 95% CI 0.48-0.55) with good agreement within the popliteal (kappa 0.67) and anterior tibial (kappa 0.61) arteries. Agreement was moderate within the pedal arterieds (kappa 0.32, 95% CI 0.24-0.40). In 74/126 (59%) limbs proposed management with DS/PGR was identical to ia-DSA. In 23/29 (79%) femoropopliteal and 15/37 (41%) femorocrural bypasses DS/PGR agreed perfectly with ia-DSA with regard to acceptor artery and anastomosis site.

CONCLUSION

DS can accurately assess the popliteal and anterior tibial arteries. In a substantial number of patients with severe lower limb ischaemia decisions for conservative management, PTA and femoropopliteal bypass can be based on a DS/PGR work-up.