Endovascular repair of chronic mesenteric occlusive disease: the role of duplex surveillance.

BACKGROUND: Chronic occlusive mesenteric ischaemia can be treated surgically or endovascularly. Endovascular techniques as elsewhere in the vascular tree are limited by restenosis. The aim of this study was to determine if duplex ultrasound proven restenosis correlates with recurrence of symptoms. METHODS: Our study looks at successful percutaneous revascularization of the mesenteric circulation associated proven restenosis using colour Doppler ultrasound and the relation to recrudescence of symptoms or weight loss. A retrospective review of five patients treated endovascularly at our institution for mesenteric angina secondary to visceral artery stenosis was carried out. RESULTS: Technical success was achieved in four out of the five patients in our study. One patient had a procedure complicated by thrombus in the coeliac axis and superior mesenteric artery (SMA) stents, subsequently showed SMA occlusion and 90% stenosis of the CA and inferior mesenteric artery and required an aorto-mesenteric graft. Three of the four patients with a technically successful procedure had significant (>70%) restenosis of the SMA. All three, including one patient with both SMA restenosis and chronic inferior mesenteric artery occlusion, remain asymptomatic and have maintained their postprocedural weight gain. CONCLUSION: Although ultrasound is a convenient, non-invasive tool for follow up of endovascular treatment of mesenteric stenosis, its use is unclear as in our study restenosis did not correlate with recrudescence of symptoms.

Comparison of duplex ultrasound with digital subtraction angiography in the assessment of infra-inguinal autologous vein bypass grafts.

BACKGROUND: Postoperative surveillance of infra-inguinal vein grafts has arisen because of the high incidence of vein graft stenoses, which frequently progress to vein graft occlusion. The use of duplex ultrasound as the primary imaging method for graft surveillance is well established. This study aims to compare the accuracy of duplex ultrasound with the reference standard of digital subtraction angiography in the assessment of infra-inguinal vein grafts. METHODS: Sixty patients underwent routine postoperative duplex ultrasound as part of the local graft surveillance programme. Angiography was subsequently carried out on 18 grafts. Each lower limb arterial tree was divided into three segments (native arteries proximal to the graft, the graft itself and native arteries distal to the graft) resulting in a total of 42 comparisons. Degree of diameter stenosis on ultrasound was compared with angiography findings to determine concordance. Agreement was also expressed as a kappa value. RESULTS: Overall accuracy of duplex ultrasound was 88% (37/42). A kappa value of 0.80 indicates good agreement. In three of the five discordant cases, ultrasound correctly identified a stenosis, but overestimated the degree of stenosis compared with angiography. In each of the remaining two discordant cases, ultrasound identified a focal stenosis that was not apparent on angiography. In both cases, the area of duplex described abnormality responded to balloon angioplasty. CONCLUSION: Duplex ultrasound as part of the local vein graft surveillance programme is a reliable and accurate method in the detection of failing grafts and in some instances may be more sensitive.

Spectral Doppler characterization of endoleaks following endoluminal abdominal aortic aneurysm repair.

BACKGROUND: Colour Doppler ultrasound of endoluminal abdominal aortic aneurysm repair is becoming an established imaging technique in identifying endoleak. Management and treatment of endoleak is determined in part by the exact nature of the endoleak, namely its type and whether it has single or multiple vessel inflow and outflow. To date, spectral Doppler waveform analysis has provided some information about the propensity for spontaneous seal of isolated type II endoleaks, rather than assisting in their classification. METHODS: We present a collection of three case reports outlining the directionality/phasicity of the Doppler waveform profile associated with endoleaks whose type and subtype (uni- /or multi-conduital) were angiographically determined. RESULTS: In all three cases uniconduital type II endoleak demonstrated a to-and-fro waveform on Doppler ultrasound imaging. CONCLUSIONS: To-and-fro Doppler waveforms may be associated with uniconduital type II endoleaks. If upon investigation of further cases this is found to be the case, this waveform classification may facilitate determination of the subtype (uni- or multi-conduital) of endoleak, thus identifying those cases which may be more amenable to percutaneous repair.