Gordon K. Stokes

Distal revascularization–interval ligation for limb salvage and maintenance of dialysis access in ischemic steal syndrome☆☆☆★

PURPOSE Traditional options for treating ischemic steal syndrome related to a functioning dialysis access graft or fistula include banding or ligation. Unfortunately, these techniques usually result in inconsistent limb salvage, loss of a functional access, or both. We report our experience with an alternative method of limb revascularization that eliminates steal while maintaining continuous dialysis access. METHODS Patients who had critical limb ischemia and functioning arteriovenous fistulae (AVF) underwent color-flow duplex scanning, digital photoplethysmography, and arteriography. Arterial ligation distal to the AVF origin eliminated the steal physiologic mechanism while arterial bypass grafting from above to below the AVF revascularized the extremity (distal revascularization-interval ligation [DRIL] procedure). RESULTS From March 1994 through December 1996, 21 patients with functioning extremity AVFs presented with critical ischemia and steal syndrome. Eleven patients had chronic ischemia with rest pain, paresthesias, or ulcerations related to nine native fistulae (six brachiocephalic, two basilic vein transpositions, one radiocephalic) and two prosthetic bridge grafts (one upper arm, one lower extremity). Acute ischemia developed in 10 patients related to three native fistulae (two brachiocephalic, one radiocephalic) and seven prosthetic bridge grafts (three forearm, three lower extremity, one upper arm). All 21 patients were treated with the DRIL technique. Three of these patients required treatment for ischemia at the time of AVF construction. Nineteen of 21 bypass procedures were performed with autogenous vein, including nine brachial-brachial, three brachial-radial, two radial-radial, two brachial-ulnar, one popliteal-popliteal, one femoral-popliteal, and one femoral-peroneal. Polytetrafluoroethylene grafts were used for one external iliac-popliteal bypass graft and one axillary-brachial bypass graft. Limb salvage and maintenance of a functional fistula were achieved in 100% and 94%, respectively, at 18 months by life-table analysis. CONCLUSION The DRIL technique reliably restores antegrade flow to the ischemic limb, eliminates the potential pathway for the steal physiologic mechanism, and maintains continuous dialysis access in these difficult patients.

Endoleak after endovascular aneurysm repair: Duplex ultrasound imaging is better than computed tomography at determining the need for intervention

OBJECTIVE Color duplex ultrasound (CDU) imaging is a noninvasive alternative to computed tomography (CT) for the detection of endoleak. This study compared CT and CDU imaging in the detection of endoleaks requiring intervention after endovascular aneurysm repair (EVAR). METHODS All EVARs performed at our institution from 1996 to 2007 were retrospectively reviewed. CDU and CT scans < or =3 months were paired and the presence of an endoleak and its type were recorded. Clinical follow-up was reviewed and interventions for endoleak were recorded. Interventions were performed for type I, for type II with sac enlargement, and for type III endoleaks. The first analysis of clinical test outcomes used the findings of CT scan as a gold standard and the second used the findings at time of intervention as a gold standard. RESULTS During the time period reviewed, 496 patients underwent EVAR, and 236 of these had CDU and CT follow-up studies paired < or =3 months of each other. Mean follow-up was 17 months (range, <1-111 months). We reviewed 944 studies or 472 pairs. Eighteen patients (7.6%) required intervention for 19 endoleaks: six type I, 11 type II, and two type III. Early endoleak (< or =1 month) requiring reintervention was detected in 1 vs late endoleak (mean, 28 months; range, 0.6-88 months) in 18. All type I and III endoleaks were treated with endovascular cuff or limb extension placement. Three type II endoleaks were treated with open ligation, and coil or glue embolization was used in eight. CDU imaging detected endoleaks requiring intervention in 89% of cases, whereas CT detected endoleak in 58% (P < .05). The ability to correctly identify the type of endoleak as confirmed at time of intervention was 74% with CDU imaging vs 42% by CT (P < .05). CDU, for the detection of endoleak requiring intervention, had a sensitivity of 90%, specificity of 81%, negative predictive value (NPV) of 99%, and positive predictive value (PPV) of 16%, while CT had a sensitivity of 58%, specificity of 87%, NPV of 98%, and PPV of 15%. CONCLUSIONS CDU imaging has a high sensitivity in detecting endoleaks requiring intervention, is better at identifying the type of endoleak, and is an excellent test for graft surveillance after endovascular aneurysm repair. Compared with CT scan, CDU imaging in our experience is the preferred test on which to base an intervention for endoleak.

Subintimal angioplasty of chronic total occlusion in iliac arteries: A safe and durable option

BACKGROUND Traditionally, aortobifemoral bypass has been the intervention of choice for iliac artery chronic total occlusions (CTOs). However, it is associated with significant morbidity and mortality, limiting its use in high-risk patients. To reduce procedural risk, subintimal angioplasty (SIA) for femoropopliteal CTO has been utilized by many, but few have extended this endovascular technique to treating iliac artery CTOs. We present our experience with 101 successful SIAs for iliac artery CTOs. METHODS A retrospective review of consecutive patients with iliac artery CTOs treated with subintimal angioplasty from June 2000 to January 2009 was completed. Demographic and risk factor data were obtained, along with procedural data. Primary and secondary patency, survival, freedom from claudication, and limb salvage rates were determined by Kaplan-Meier survival analysis. Univariate and multivariate analyses were completed to identify factors adversely affecting primary patency. RESULTS One hundred twenty patients underwent an attempted SIA of an iliac artery CTO, and 101 iliac artery CTOs were successfully treated, giving a technical success rate of 84%. Technical failure was due to the inability to re-enter the lumen in all cases. Indications for intervention were lifestyle-altering claudication in 64 patients (63%) and critical limb ischemia (CLI), in 37 (37%). Eighty-five patients underwent percutaneous SIA, while 11 patients underwent a combined SIA with surgical outflow procedure. Lesions were classified as TransAtlantic InterSociety Consensus (TASC) B, 39 (39%); TASC C, 27 (27%); and TASC D, 35 (35%). In 82 (81%) lesions, stents were deployed with an average of 1.2 (range, 0-3) stents utilized. A re-entry device was used in 14 (14%) lesions. Major complication rate was 3.0%, with a 30-day mortality rate of 1.0%. Primary and secondary patency rates at 1, 2, and 3 years were 86% and 94%, 76% and 92%, and 68% and 80%, respectively. Survival rate was 67% at 5 years, reflecting the poor health of this cohort. Limb salvage for CLI patients at 1 and 5 years was 97% and 95%, respectively. Freedom from claudication at 1 and 3 years was 89% and 73%. Univariate analysis identified hyperlipidemia, coronary artery disease, and prior surgical bypass in treated limb as factors for loss of primary patency; however, on multivariate analysis, no factors remained statistically significant. CONCLUSION This study demonstrates that SIA of iliac CTOs is feasible and can be performed safely and effectively, even in high-risk patients. Excellent patency and limb salvage rates can be achieved. In our experience, the safety and durability of SIA makes it an attractive first-line therapy for iliac artery occlusive disease.

Selective stenting in subintimal angioplasty: Analysis of primary stent outcomes

OBJECTIVE Subintimal angioplasty (SIA) is being increasingly utilized to treat chronic arterial occlusions. The role of stents in SIA is currently unknown. We performed a retrospective review of selective stent use in SIA to assess outcomes and factors affecting these results. METHODS A retrospective review of patient information--including demographics, indications, procedures, noninvasive studies, and post-procedural events--was performed on our database for patients undergoing SIA in the superficial femoral and popliteal arteries. Outcomes were calculated only on technically successful SIAs using Kaplan-Meier survival analysis. Continuous and non-continuous data were compared using the Student t test and the z test, respectively. Survival curves were compared using log-rank testing for univariate analysis and Cox hazard-regression analysis for multivariate analysis. RESULTS Three-hundred-sixty-eight patients (382 limbs) underwent femoral and/or popliteal SIA for critical limb ischemia or disabling claudication from December 1, 2002 through July 31, 2006. Eighty-four limbs (22%) had a stent placed, while 298 (78%) did not receive a stent. Mean follow-up was 11.7 months (range, 0-45 months). One-year primary and secondary patency for stent vs no-stent group was 50% vs 45% (P = .73) and 70% vs 78% (P = .47), respectively. One-year limb salvage rate for the stent vs no-stent group was 85% vs 90% (P = .61). At 2 years, patients receiving a stent are more likely to undergo open bypass than those without a stent (P = .06). Eighty-three patients underwent 84 SIA with stent placement. The mean number of stents for each case was 1.4 +/- 0.7. Univariate analysis revealed that previous ipsilateral bypass surgery significantly decreased 1-year patency: 35% vs 56% (P = .05). SIA performed for disabling claudication had a trend toward improved 1-year patency 58% vs 39% for critical limb ischemia (P = .09). A stent diameter > or =7 mm displayed a trend toward better patency 53% vs 37% for diameter < or =6 mm (P = .08). None of these factors proved significant with multivariate analysis. CONCLUSION Selective stents placed for suboptimal results after subintimal angioplasty produce similar patency rates to primary SIA without stents. Patients receiving stents with prior lower extremity bypass surgery will have worse outcomes than those without. Use of a stent diameter < or =6 mm and indication of critical limb ischemia will likely produce worse results. It appears that other stent variables (location, number, length, and overlap) do not alter patency. Finally, selective stent use after SIA provides excellent limb salvage.

Retrograde open mesenteric stenting for acute mesenteric ischemia is a viable alternative for emergent revascularization.

Objectives: Significant comorbidities and an exhausted physiologic reserve lead to high mortality rates during operations for acute mesenteric ischemia. We present our experience with retrograde open mesenteric stenting. Methods/Results: A total of 3 female patients (mean age = 74.1 years) with acute mesenteric ischemia underwent exploratory laparotomy. Operative technique included isolating the superior mesenteric artery for cannulation and retrograde endovascular angioplasty and stenting. One required small bowel resection. All 3 patients survived. Mean follow-up was 8.4 months (range: 1.2-16.6). All remain with a 100% primary patency rate. Conclusion: Retrograde open mesenteric stenting for acute mesenteric ischemia is a viable alternative to bypass.

Successful repair of a ruptured Stanford type B aortic dissection during pregnancy

We present our experience with an acute Stanford type B aortic dissection in a 25-year-old, 26-week gravid patient without a known connective tissue disorder and discuss a literature-based treatment strategy. After failed conservative treatment manifest by aneurysm rupture, emergency cesarean section delivery and immediate repair of her thoracic aorta was performed. Seven months later, she is fully caring for her healthy baby. During pregnancy, thoracic aortic dissection occurs from physiologic and hemodynamic changes. Emergency cesarean delivery, followed by immediate aortic repair, is the treatment choice if malperfusion syndrome, rupture, uncontrolled hypertension, or unremitting pain occurs.

Outcomes of reinterventions after subintimal angioplasty

OBJECTIVE With increased use of subintimal angioplasty (SIA), the role of reintervention after recurrence is currently unknown. To more clearly define the technical feasibility, patency, and clinical outcomes of reinterventions after SIA, we reviewed our cumulative experience. METHODS A retrospective review of patient information (including demographics, indications, procedures, noninvasive arterial studies, and postprocedural events) was performed on those patients undergoing reintervention after a primary subintimal angioplasty in the infrainguinal vessels. Continuous and noncontinuous data were compared using the Student t-test and the z test, respectively. Patency was calculated by Kaplan-Meier analysis. Survival curves were compared using log-rank and Wilcoxon testing for univariate analysis and Cox hazard-regression analysis for multivariate analysis. RESULTS From December 2002, through July 2006, 495 SIAs were performed for infrainguinal disease in 482 patients. Of this cohort, 121 patients (25%) required 188 consecutive reinterventions. Each patient underwent an average of 1.5 +/- 0.8 (range, 1-7) reinterventions during this study. We analyzed only the outcomes of 124 consecutive, first reinterventions. Mean interval time between primary SIA and the first reintervention was 7.8 +/- 6.8 months (range, 1 day-31 months). Indications for reintervention were clinical only (recurrence of symptoms or worsening exam), diagnostics only (recurrence based on peripheral vascular lab studies), or both in 18%, 25%, and 52% of patients, respectively. Technical success was achieved in 94% (n = 117) of the procedures. Repeat SIA technique was utilized in 68% (n = 84) of reinterventions and other endovascular therapies (32%; n = 40), of which the majority were transluminal angioplasty, for the remaining reinterventions. Mean follow-up was 8.6 months (range, 0-34 months). The patency rate at 1 year for the first reintervention was 33%. One-year patency rates for reinterventions performed within 3 months of the primary SIA were worse than those performed after 3 months (22% vs 34%; P = .04). In addition, patients treated for claudication had better 1-year patency than those treated for critical limb ischemia (37% vs 27%; P = .03). Other demographic or procedural variables did not significantly affect patency. In patients with critical limb ischemia (CLI), limb salvage rate at 1 year was 71%. CONCLUSION Endovascular reintervention after SIA is a safe and technically feasible procedure for recurrences and offers good limb salvage rate. Early reinterventions performed within 3 months of the original SIA portend a worse outcome. In addition, reinterventions are less durable in patients with CLI compared with claudication. Finally, by identifying a recurrent stenosis instead of an occlusion, close surveillance may contribute to improved overall outcome.