ReviewPeripheral arterial disease is highly prevalent in the general population affecting 12 to 14% of people and leading to claudication or threatened limb ischemia. 1 Endovascular lower extremity arterial interventions have increased exponentially over the past decade. 2 The femoropopliteal (FP) segment represents 40% of vessels treated and its treatment continues to be a challenge to the endovascular specialist. Despite a high rate of acute procedural success, target lesion revascularization (TLR) and target vessel revascularization remain elevated. 3,4 We have previously proposed a triad of optimal peripheral vascular revascularization strategy (►Fig. 1) 5 with an emphasis on three key principles: (1) Mechanical, improve vessel compliance to allow dilatation of a stenotic segment at low balloon inflation pressure and reduce dissection and recoil. Low balloon inflation pressure would theoretically preserve vessel integrity by minimizing barotrauma and bailout stenting. (2) Biological, inhibit smooth muscle cell (SMC) proliferation to improve patency rates and reduce repeat revascularization. (3) Procedural, preserve the outflow vessels by minimizing distal embolization (DE) and reduce procedural time and radiation exposure to both operator and patient.In this overview, we examine these principles to determine whether current data support their validity. We recognize the lack of uniform performance criteria and reporting standards in clinical trials in peripheral arterial disease. This unfortunately makes comparisons across studies difficult.
Mechanical FactorsThe concept of improving vessel compliance as a prerequisite to a more definitive treatment of the FP artery has gained more attention over the past few years. Measurement of vessel compliance in vivo is difficult to obtain. One surrogate endpoint is the minimum balloon pressure (MBP) needed to fully stretch the artery to a lumen diameter equal to a normal reference segment with the use of a noncompliant balloon sized 1:1 to the reference vessel. The balloon is typically inflated to two atmospheres then the inflation pressure is increased by increment of one atmosphere at a time until full balloon expansion is achieved. 6,7 According to Laplace's law, tension (T) in the vessel wall is equal to (pressure (P) gradient across the arterial wall * radius (R) of artery)/wall thickening (M), or (T¼ [P * R]/M). In order for MBP change to reflect on compliance, the segments under comparison need to have similar radius and lesion
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AbstractTreatment of the femoropopliteal (FP) artery remains a challenge to the endovascular specialist. Long-term patency is low with a high rate of target lesion revascularization. The true patency rate varies considerably between studies partly because there is a lack of uniform performance criteria and reporting standards in peripheral arterial interventions. Literature review supports three principles that emerge as important components of an optimal strategy in treating the FP artery: (1) improving vessel compliance and sub...