Abstract
Purpose
To evaluate our experience of limb salvage with bare nitinol stent enabled recanalization of long length occlusions of superficial femoral artery (SFA) and adjacent proximal popliteal artery (PPA) in diabetic patients.
Methods
A total of 573 patients underwent 842 lower limb interventions from August 2006 to September 2008 at our institute. A retrospective review was done of diabetic patients undergoing recanalization of long length SFA/adjacent PPA (>10 cm) occlusions with self expanding bare nitinol stents evaluating their impact on limb salvage.
Results
Forty-four patients (mean age 65.2 years, M:F 25:19) underwent 49 long-length (>10 cm) SFA/PPA stenting procedures over a period of 26 months. Diabetics comprised 66% of patients ( n =29, mean age: 63.7 years, M: F 19:10). The infrapopliteal distal run-off in this diabetic subgroup comprised one vessel ( n =14/29, 48%), two vessels ( n =12/29, 41%), and three vessels ( n =3/29, 10%). The spectrum of critical limb ischemia included rest pain ( n =8), ulcer ( n =7) and gangrene ( n =14). The lengths of occlusions recanalized were 10–39 cm. A total of 58 stents (individual length 10–17 cm, average diameter 6 mm, mean 2 stents per patient) were placed with average length of stented segment being 23.8 cm. Four patients had stents placed through ipsilateral popliteal artery approach with rest placed through femoral artery approach. Significant complications of the procedure included distal embolization ( n =3) successfully managed with thrombolysis and popliteal arteriovenous fistula in one patient undergoing recanalization through popliteal approach, managed with covered stent placement. No procedure related mortality occurred during thirty-day follow-up period. All were followed up over an average duration of twelve months post-procedure. Three patients died due to associated medical conditions during this period. The following amputations were done on follow-up (three toe amputations, five forefoot amputations, three below-knee amputations, two above-knee amputations). The overall limb salvage rate was 80%.
Conclusion
Our study shows beneficial result of SFA/PPA stent placement in diabetic occlusions with significant concomitant infrapopliteal disease.
1
Introduction
Peripheral arterial disease (PAD) is a significant healthcare problem affecting the elderly population. Its incidence increases from 4% in population 40 years and older to 15% in patients over 70 years of age . It presents with intermittent claudication at its early stage, progressing to rest pain and tissue loss as a manifestation of advanced disease. A large proportion of patients with early PAD do not have classical clinical presentation making its detection and management challenging .
PAD is estimated to affect 12–20% of Americans over 65 years of age. Despite the high prevalence of PAD, it still remains an overwhelmingly under-diagnosed disease. Due to its indolent presentation at early stage, only 25% of the patients undergo treatment at any time for the disease . In our local population in Singapore, the incidence of PAD is around 8% .
Diabetes is a strong risk factor for PAD along with cigarette smoking . Most patients with diabetes have significant involvement of the infrapopliteal arteries . A significant proportion of patients with diabetes also have renal failure that additionally affects their peripheral arteries . These factors make management of the disease challenging in these individuals.
Critical limb ischemia has an incidence of 500–1000 new cases per million persons per year, with the peak incidence in the age group between 70 and 79 years . It is important to salvage their limbs as the overall survival is significantly reduced after major limb amputation .
In this article, we describe our results of limb salvage following recanalization of occlusions of superficial femoral artery (SFA) and proximal popliteal artery (PPA) using long self expanding nitinol stents in patients with diabetes.
2
Materials and methods
We started our local registry of patients presenting with critical limb ischemia in January 2006. Our study is based on endovascular revascularization as the first line approach for limb salvage in all patients presenting with critical limb ischemia.
All patients had initial assessment of the arterial supply to the affected limb using Doppler ultrasound. This was followed by diagnostic catheter angiogram and intervention, if required, at the same session. The primary aim of intervention was to establish straight line flow of at least one vessel to the foot. After crossing the occlusions, angiogram was performed to confirm intraluminal position distal to the occlusion.
In patients in whom the occlusions could not be crossed or were not technically feasible using common femoral artery approach, ipsilateral popliteal artery access was used for retrograde recanalization of SFA/PPA. Assistance in crossing occlusions using reentry catheters such as Outback reentry catheter (Cordis, Miami, FL, USA) and Front-runner reentry catheter (Cordis, Miami, FL, USA) were used as appropriate. This approach enabled us to achieve an overall technical success rate of 96%.
All patients had an initial attempt to revascularize the occluded artery with balloon catheters, the size and length of which was estimated on the basis of measurement on diagnostic angiogram prior to intervention. Stents were used only if the result of balloon angioplasty was suboptimal, defined as lesions that were elastic post angioplasty, lesions that showed flow-limiting dissection and lesions that had more than 50% residual stenosis post angioplasty. These were placed only if there was at least one vessel run-off below the knee (anterior or posterior tibial artery preferentially) into the foot. In cases with concomitant infrapopliteal arterial occlusions, the disease below the knee was treated and recanalized prior to stent placement in SFA/PPA. All stents were then postdilated at nominal pressure with the same size balloon after deployment.
In patients with long SFA/PPA occlusions, longest available stents were used in order to keep overlap to the minimum. The stents used in our series included Smart Control (Cordis), Protégé Everflex (ev3, Plymouth, MN, USA) and Lifestent Flexstar XL (Edwards Lifesciences, Irvine, CA, USA).
All patients were placed on dual antiplatelet therapy following the procedure (clopidogrel and aspirin). Clopidogrel was given for at least 4 months after the procedure, with aspirin continued long term.
All patients were followed up for at least one year after stent placement with regular clinical surveillance and Doppler scans. Catheter angiogram and re-intervention was performed in patients with recurrent stenosis or those with new lesions elsewhere in the same limb. The overall limb salvage rate was evaluated in all patients.
2
Materials and methods
We started our local registry of patients presenting with critical limb ischemia in January 2006. Our study is based on endovascular revascularization as the first line approach for limb salvage in all patients presenting with critical limb ischemia.
All patients had initial assessment of the arterial supply to the affected limb using Doppler ultrasound. This was followed by diagnostic catheter angiogram and intervention, if required, at the same session. The primary aim of intervention was to establish straight line flow of at least one vessel to the foot. After crossing the occlusions, angiogram was performed to confirm intraluminal position distal to the occlusion.
In patients in whom the occlusions could not be crossed or were not technically feasible using common femoral artery approach, ipsilateral popliteal artery access was used for retrograde recanalization of SFA/PPA. Assistance in crossing occlusions using reentry catheters such as Outback reentry catheter (Cordis, Miami, FL, USA) and Front-runner reentry catheter (Cordis, Miami, FL, USA) were used as appropriate. This approach enabled us to achieve an overall technical success rate of 96%.
All patients had an initial attempt to revascularize the occluded artery with balloon catheters, the size and length of which was estimated on the basis of measurement on diagnostic angiogram prior to intervention. Stents were used only if the result of balloon angioplasty was suboptimal, defined as lesions that were elastic post angioplasty, lesions that showed flow-limiting dissection and lesions that had more than 50% residual stenosis post angioplasty. These were placed only if there was at least one vessel run-off below the knee (anterior or posterior tibial artery preferentially) into the foot. In cases with concomitant infrapopliteal arterial occlusions, the disease below the knee was treated and recanalized prior to stent placement in SFA/PPA. All stents were then postdilated at nominal pressure with the same size balloon after deployment.
In patients with long SFA/PPA occlusions, longest available stents were used in order to keep overlap to the minimum. The stents used in our series included Smart Control (Cordis), Protégé Everflex (ev3, Plymouth, MN, USA) and Lifestent Flexstar XL (Edwards Lifesciences, Irvine, CA, USA).
All patients were placed on dual antiplatelet therapy following the procedure (clopidogrel and aspirin). Clopidogrel was given for at least 4 months after the procedure, with aspirin continued long term.
All patients were followed up for at least one year after stent placement with regular clinical surveillance and Doppler scans. Catheter angiogram and re-intervention was performed in patients with recurrent stenosis or those with new lesions elsewhere in the same limb. The overall limb salvage rate was evaluated in all patients.
3
Results
Eight hundred forty-two lower limb peripheral vascular interventions in 573 patients were performed at our institute over a period of 30 months from August 2006 to December 2008. Of these interventions, 96% were performed on patients with critical limb ischemia; 65% patients had concomitant supra- and infrapopliteal stenotic/occlusive disease requiring treatment at the same session; and 30% of patients had long segment occlusions involving supra- or infrapopliteal arteries or both.
Forty-four patients underwent 49 long-length SFA/PPA stenting procedures over a period of 26 months. These comprised 25 male and 19 female patients, with a mean age of 65.2 years. Diabetics comprised 66% ( n =29) of these patients.
The presenting complaints were rest pain in eight, ulcer in seven, and gangrene in 14 patients. The lengths of occlusions recanalized were 10–39 cm (mean length 20 cm). A total of 58 stents (individual length 10–17 cm, average diameter 6 mm, mean 2 stents per patient) were placed with the average length of stented segment being 23.8 cm.
The infrapopliteal distal run-off in this diabetic subgroup comprised one vessel ( n =14/29, 48%), two vessels ( n =12/29, 41%), and three vessels ( n =3/29, 10%) ( Table 1 ).
