Abstract
Stenoses or occlusions in the superficial femoral artery (SFA) are a common manifestation of peripheral artery disease (PAD), especially in diabetic individuals. These pathologies may be treated using a number of modalities, depending mostly on the anatomical characteristics of the lesion and the patient's comorbid conditions. Percutaneous transluminal angioplasty (PTA) with or without the concomitant use of stents is the most popular solution in current practice, employed in lesions measuring <10 cm in length. A recent systematic review investigating PTA plus stenting for stenotic and occluded SFAs concluded that this intervention has a small but significant improved short-term primary patency over lesions treated with PTA alone; a lesser effect is seen for the ankle-brachial pressure index (ABPI), but no difference was documented in terms of quality of life at any time interval. 1
Antegrade subintimal angioplasty has been traditionally applied for treatment of occlusive SFA lesions; however, arterial access can prove challenging in a number of cases, and re-entering the true lumen is not always feasible. The retrograde approach via the popliteal artery has, therefore, been advocated in unfavorable anatomies where antegrade approach via the common femoral artery proves difficult.2–5 This alternative technique, however, involves repositioning the patient during the procedure, and access-related complications at the popliteal axis could, at least theoretically, lead to acute limb ischemia postoperatively.3–5
A modified technique, as proposed by Kawarada et al., 6 involves lifting the patient's heel in order to access the popliteal tree for puncture, thus obviating a position change during the procedure. However, puncture-related complications (hematoma, pseudoaneurysm, arterial occlusion) and prolonged postoperative immobility remain important issues, even after using the latest endovascular devices, which do not need a large (>6- F) sheath for stent introduction. Direct puncture of a diseased popliteal artery should be the “final” solution and done only by expert hands, given the high probability of disabling complications.
Additionally, in cases of failed antegrade angioplasty for occlusive SFA lesions, the initial failure to re-enter the true lumen usually suggests excessive calcification of the atheromatous plaque, especially when taking into account the fact that most of these patients are diabetics with various comorbidities. As a result, a below-knee femorodistal bypass using a venous graft should probably be considered as the first-choice procedure, since it has acceptable midterm results in this category of patients.7–9 Moreover, if a venous graft cannot be used, a polytetrafluoroethylene graft can also be utilized.
The antegrade ipsilateral approach through the ipsilateral common femoral artery indeed does provide superior maneuverability compared to the contralateral femoral artery crossover technique. If ipsilateral puncture proves difficult, a small femoral “cut-down” can be employed under regional anesthesia to achieve direct femoral puncture prior to resorting to the retrograde popliteal approach. Overall, interventionists should always be clear on why they chose an endovascular approach to begin with and justify the retrograde approach accordingly, after having considered the alternatives.
Moreover, patients presenting with critical limb ischemia need to be offered maximal treatment of all stenotic or occlusive lesions of the relative arterial segment. In other words, especially in diabetic individuals, recanalizing the SFA and leaving the rest of the vascular bed (the remaining SFA, popliteal artery, orifice of the tibioperoneal trunk) untreated would place the patient under the risk of early recurrence or primary failure. The most convenient way to achieve that is a femorodistal venous bypass graft, since this would allow “bypassing” even the most significant (lengthy) lesions in the affected segment.
Additionally, it is important to mention that an increase of the ABPI in this patient group with advanced calcification of the vasculature is not an efficient index of distal perfusion and should be used in addition to quality of life indicators and the patient's clinical picture during follow-up. 10
Conclusively, treating occlusive lesions of the SFA with PTA plus stenting can prove challenging in terms of access and re-entry into the true lumen. A retrograde approach via the popliteal artery using the modified technique described by Kawarada et al. 6 is a viable alternative; however, this should be the last resort after careful consideration of other therapeutic modalities, such as the use of a venous bypass, since puncture site complications can be significant. Follow-up should include quality of life indicators, a careful clinical examination to assess tissue loss, and peripheral perfusion as well as serial ABPI measurements.