Techniques in Vascular and Interventional Radiology最新文献

Peripheral artery disease (PAD) is a progressive vascular disease affecting millions of individuals and is a considerable cause of morbidity and mortality worldwide. While balloon angioplasty remains the cornerstone option for endovascular management of arterial stenosis, advances in percutaneous endovascular stent technology have broadened the toolbox of therapeutic options for PAD and have significantly improved function and quality of life. Indeed, covered stents, bioabsorbable stents and drug eluting stents are several of the innovations in stent technology made since the advent of nitinol bare metal stents in the 1980s. The indications for use, technical considerations, treatment outcomes, and current concerns regarding current stent devices will herein be discussed in this review.

Chronic total occlusions are a common cause of both claudication and critical limb ischemia. Currently, 40%-50% of all individuals undergoing lower extremity interventions will have a chronic total occlusion. Endovascular specialist should be familiar with the different treatment algorithms and classifications systems. Many different techniques have been shown to be successful in crossing the lesion and for re-entry when needed. The vascular access obtained to cross the lesion is frequently dictated by lesion location, lesion length, and the distal runoff in the affected limb.

In the management of patients with critical limb ischemia endovascular revascularization plays a crucial role improving amputation-free survival, ischemic rest pain, and wound healing. Endovascular standard of care of peripheral arterial occlusive disease involves angioplasty and/or stent placement. The following discussion is intended to familiarize interventional physicians with the rationale, physiological concepts, and technical approach to developing endovascular procedures—percutaneous femoropopliteal bypass and percutaneous deep vein arterialization. Percutaneous arterial bypass procedure is designed to treat long complex Trans-Atlantic Inter-Society Consensus C and D hemodynamically significant superficial femoral artery lesions by redirecting the flow of blood from the diseased arterial segment through a femoral vein conduit. Percutaneous deep vein arterialization is used for selected “no-option” critical limb ischemia patients who cannot undergo or have failed conventional endovascular and/or surgical revascularization due to extensive occlusion of the outflow arteries. It involves creation of an arteriovenous fistula between a tibial artery and a tibial vein, disruption of venous valves, and elimination of venous collaterals. The consequent arterialization of the distal venous bed enables delivery of oxygenated pressurized arterial blood to the ischemic tissues, stimulating angiogenesis and increasing flow in the existent collateral vessels, which in turn will improve limb salvage and amputation free survival.

The field of Interventional Radiology is said to have begun in 1964, when Dotter successfully restored circulation to an 82-year-old woman's leg with critical limb ischemia and gangrene by percutaneously dilating a localized stenosis of the superficial femoral artery using a Teflon catheter. The dilation catheter was revolutionary in the inception of angioplasty, and progress evolved with the development of angioplasty balloons. As angioplasty became more widely utilized, the focus turned to improving its results. Several factors are important to consider with regards to maximizing angioplasty results in peripheral interventions. These factors include vessel size, lesion length, lesion location, and the anatomic vascular bed. Operators must make thoughtful decisions regarding balloon choice, diameter, length, inflation pressures, inflation time, and employ these devices with excellent technique to optimize outcomes. Complications from angioplasty include elastic recoil, vessel dissection, vessel rupture, distal embolization, and neointimal hyperplasia. The most widely recognized limitation of angioplasty is the longevity of treatment effect. In order to improve long-term outcomes, different specialty balloons have been developed to address lesions resistant to plain balloon angioplasty and combat neointimal hyperplasia to improve outcomes. Ultimately the goal is to maximize vessel patency for the longest duration possible, and many exciting new technologies are on the horizon.

Arterial calcification (AC) is a common complication among patients with peripheral arterial disease (PAD). AC presents various challenges to PAD treatment including an increased likelihood of vessel rupture and dissection, and by acting as a physical barrier to drug delivery by angioplasty balloons. Intravascular lithotripsy (IVL) is a novel intervention that specifically targets AC by emitting sonic pressure waves that introduce microfractures in target calcified lesions to increase arterial compliance. Preliminary data has demonstrated the safety and efficacy of IVL in PAD treatment. The present article provides a technical overview of S-IVL, as well as a case series of the treatment of AC in common iliac, common femoral, superficial femoral, aortoiliac, and peroneal arterial lesions. Each case resulted in marked improvement of luminal patency, exhibiting the efficacy IVL.

Multiple or alternate arterial accesses are often required when tackling more challenging peripheral arterial disease (PAD). Knowledge and familiarity in performing antegrade femoral, popliteal, tibial, and upper extremity access can improve the success rate of complex PAD interventions. This article provides a detailed review of indications, technical how-tos, and outcomes of these alternative accesses.

Peripheral arterial disease is a condition associated with high rates of cardiovascular morbidity and mortality, increased risk of adverse limb events, including development of critical limb ischemia and amputation, and also with decreased quality of life. This manuscript provides an overview of the medical management of patients with peripheral arterial disease. We discuss contemporary therapies that decrease major adverse cardiovascular and limb events among patients with peripheral arterial disease, and also therapies that improve the patient's ability to walk and quality of life in general.

Autonomously functioning thyroid nodules (AFTN) are a common cause of hyperthyroid symptoms. While hemithyroidectomy or radioactive iodine ablation have historically been used to treat AFTNs, percutaneous thyroid radiofrequency ablation (RFA) is emerging as a promising option for outpatient therapy. The technique is compared to medical therapy, radioactive iodine therapy, and surgery, with an emphasis on technical differences in the ablation procedure for AFTN vs other benign thyroid nodules.

In addition to the basic techniques used in radiofrequency ablation of thyroid nodules, a variety of more advanced techniques have been developed. To address hyper-vascular nodules, vascular ablative techniques have been described. Protective hydro-dissection can be used around the carotid artery and the trachea to improve safety. Rescue hydro dissection can be used to reverse nerve injury. Additionally, several new ablation devices show promise at increasing efficacy and safety. These techniques and devices will be reviewed to provide an understanding of these advanced techniques and novel devices.

While radiofrequency ablation (RFA) for the treatment of symptomatic thyroid nodules has been gaining more widespread adoption in the United States, there is limited societal guidance for its role, and safe adoption. As many of the first adopters of thyroid nodule RFA developed their practices, they looked to the Korean Society of Interventional Radiology (KSIR), and European Thyroid Association (ETA) guidelines as a framework. Currently, efforts are underway from the American Thyroid Association to create updated guidelines for US providers. International consensus guidelines are also underway. Until these guidelines are available, a thorough understanding of the current available guidelines is key for interventionalists building a thyroid nodule RFA program.