B P5 C44 Treatment of Noncoronary Obstructive Vascular Disease Flashcards
_____ is a general term that includes pathologic processes affecting arteries, veins, and lymphatics
Peripheral vascular disease
_____ PAD may be asymptomatic or may manifest as claudication, critical limb ischemia (CLI), or embolic infarction of a distal organ
(e.g., stroke)
Chronic
Asymptomatic disease is common. In the lower extremities, asymptomatic disease occurs in at least half and in as many as 80% of patients with abnormal functional test results indicative of obstructive arterial disease (e.g., abnormal ABI).
Even asymptomatic disease indicates elevated CV risk. These considerations warrant _____ risk factors as a prime goal of therapy to reduce the risk for myocardial infarction (MI) and stroke, the most common causes of death in patients with PAD.
Intensive modification of atherosclerosis
_____ classically refers to leg discomfort, weakness, or pain related to exercise and relieved by rest, but it also describes discomfort in the upper limbs caused by effort-related ischemia.
Claudication
Supervised exercise training consisting of _____ is particularly useful at improving walking, with or without endovascular intervention
1-hour sessions two to three times a week for 12 weeks
_____ strategies aim to improve arterial blood flow in obstructed large- and medium-sized arteries when noninvasive therapies fail.
Revascularization
_____, also referred to as critical limb-threatening ischemia, refers to PAD with ischemic pain at rest or tissue loss (e.g., ulcer or gangrene).
This scenario has clinical urgency because of near- term risk for limb jeopardy requiring major amputation
Critical limb ischemia
_____ amputation in the lower limbs refers to amputation at or above the level of the ankle and requires a prosthesis for the patient to walk.11 Amputation is disfiguring and at higher levels (above versus below knee amputation) has greater impact on functional independence of the patient
Major
_____ amputations (e.g., toe or transmetatarsal) usually have little impact on the patient’s ability to walk. Catheter-based therapies for CLI are used to improve blood flow and heal ischemic tissue, to salvage the limb (prevent major amputation), or to enable a lower level of amputation that might have less impact on the patient’s ability to walk
Minor
The risk for major stroke is high shortly after a symptomatic event but declines to the level of asymptomatic disease after approximately _____ months.
3 months
_____ remains the mainstay of endovascular intervention for PAD and venous disease
Balloon angioplasty
Angioplasty remodels the artery by expansion and accommodates the atherosclerotic plaque to expand the vessel lumen.
This procedure usually causes _____ of the plaque that may or may not impair blood flow.
Dissection
Angioplasty is limited in the short term by acute recoil of the artery and flow-limiting dissections, which may cause abrupt closure of the artery.
Angioplasty is limited in the short term by acute recoil of the artery and flow-limiting dissections, which may cause abrupt closure of the artery. In the intermediate time frame, _____ may lead to symptomatic restenosis
Overexuberant neointimal hyperplasia and negative remodeling of the artery
Most operators use prolonged inflations (at least ____ minute or more)
1 min or more
Bare-metal stents (BMSs) come in two types:
Balloon-expandable stents
Self-expanding stents
______ stents have greater radial strength and are less likely to move on deployment, which is important for ostial placement.
Balloon-expandable stents
Such stents can be crushed by external compression and are therefore avoided outside the torso.
They are sometimes used to treat tibial dis- ease, but only for CLI, for which long-term patency may be less of an issue once tissue healing has occurred.
_____ stents were originally made of stainless steel but are now usually made of nitinol. Nitinol stents reexpand on compression and are therefore used outside the torso, where external compression is more likely to occur.
Self-expanding stents
They may also be used in tortuous arteries, where they probably conform better than balloon-expandable stents. Their lower radial strength, however, increases the risk for recoil. Con- temporary self-expanding stent designs are more durable and less likely to fracture than older designs.
______ stents using a polymer or polymer-free coating of paclitaxel offer lower rates of restenosis than bare-metal self-expanding stents.
Drug coated self-expanding stents
In the _____ study, a polymer-coated paclitaxel stent had similar 12 months of efficacy and safety outcomes to a polymer-free paclitaxel stent, and a single-arm cohort study suggested no “catch-up” target vessel revascularization over 3 years with this device.
IMPERIAL
The duration of DAPT required for these stents (Drug coated self-expanding stents) is uncertain, but recent randomized trials have generally used _____ months of treatment with an adenosine receptor antagonist.
2-6 months
Compared with plain balloon angioplasty, drug- coated balloons have less _____ and repeat in the femoral- popliteal arteries, and similar patency to drug-coated self-expanding stents
Less restenosis and repeat revascularization
Drug-coated balloons also offer a lower risk of restenosis at 1 year compared with plain balloon angioplasty for treating in- stent restenosis lesions
The duration of DAPT with drug-coated balloons in the femoral-popliteal arteries is uncertain but varies between _____ months in most randomized trials.
1-6 months
However, in 2018 a group-level meta-analysis of randomized trials suggested that patients treated with paclitaxel drug-coated balloons or stents for femoral-popliteal disease had _____ rates of mortality 2 to 5 years after their procedure compared with non-paclitaxel balloons and stents
Higher
_____ is a key determinant of restenosis, and a meta-analysis suggests that long lesions have less restenosis and need for target revascularization with paclitaxel drug-coated balloons and stents
Lesion length