Michael A. Bettmann

Carotid Stenting and Angioplasty A Statement for Healthcare Professionals From the Councils on Cardiovascular Radiology, Stroke, Cardio-Thoracic and Vascular Surgery, Epidemiology and Prevention, and Clinical Cardiology, American Heart Association

Carotid artery stenosis, particularly involving the origin of the internal carotid artery, is a frequent clinical problem. These stenoses, almost invariably atherosclerotic, can present as asymptomatic bruits discovered on physical examination, one or more transient ischemic attacks related to embolization of thrombus from stenotic lesions or to hypoperfusion, or less commonly, as an ischemic stroke. From the results of three high-quality prospective randomized trials,1 2 3 it has become apparent that symptomatic stenoses that narrow the diameter of the carotid artery more than 60% to 70% lead to a significant incidence of stroke if treated medically. The risk of stroke associated with such a lesion in symptomatic patients treated with antiplatelet therapy alone is thought to be 26%.3 With carotid endarterectomy and aspirin, this risk is lowered to 9%, a statistically significant difference.3 In patients with or without symptoms who have a stenosis ≤60%, the effectiveness of either medical therapy or carotid endarterectomy in preventing significant neurological events is not known. In symptomatic patients with <30% stenosis, medical therapy is superior to surgical therapy.2 Studies attempting to define the benefit of therapy in symptomatic patients with <60% stenosis are currently under way. Accrual of patients has slowed, however, because data show clear efficacy in symptomatic patients with stenoses ≥70%, leading to a bias toward surgery in symptomatic patients with less severe stenoses. In general the role of surgery for asymptomatic stenosis remains controversial, with some recent opinions suggesting that it may not be indicated.4 In one high-quality trial with selected experienced surgeons, there was a modest reduction in absolute risk in asymptomatic patients with stenosis ≥60%, but the significance of this finding has been debated.5 6 nnAlthough mortality associated with conventional antiplatelet therapy has been minimal,7 surgery clearly has significant perioperative morbidity and …

Atherosclerotic vascular disease conference: Executive summary: Atherosclerotic vascular disease conference proceeding for healthcare professionals from a special writing group of the American Heart Association

Atherosclerosis is one of the most important and common causes of death and disability in the United States and throughout the world. More than 25 million persons in the United States have at least one clinical manifestation of atherosclerosis, and in many more, atherosclerosis remains an occult but important harbinger of significant cardiovascular events. Throughout the last half of the past century, coronary artery atherosclerosis has been a major focus for basic and clinical investigation. As a result, considerable strides have been made in the development of programs to prevent and treat the clinical manifestations of coronary artery disease. The development of lipid-lowering, antithrombotic, thrombolytic, and catheter-based therapies in particular has had considerable impact in reducing death and disability from coronary atherosclerosis. Yet atherosclerosis is a systemic disease with important sequelae in many other regional circulations, including those supplying the brain, kidneys, mesentery, and limbs. Persons with cerebral atherosclerosis are at increased risk for ischemic stroke. Those with renal artery atherosclerosis are at risk for severe and refractory hypertension as well as renal failure. Patients with atherosclerosis affecting the limb, ie, peripheral arterial disease (PAD), can develop disabling symptoms of claudication or critical limb ischemia and its associated threat to limb viability. Moreover, once disease is apparent in one vascular territory, there is increased risk for adverse events in other territories. For example, patients with PAD have a 4-fold greater risk of myocardial infarction and a 2- to 3-fold greater risk of stroke than patients without PAD.

Guidelines for the Reporting of Renal Artery Revascularization in Clinical Trials

Although the treatment of atherosclerotic renal artery stenosis with use of percutaneous angioplasty, stent placement, and surgical revascularization has gained widespread use, there exist few prospective randomized controlled trials (RCTs) comparing these techniques to each other or against the standard of medical management alone. To facilitate this process as well as help answer many important questions regarding the appropriate application of renal revascularization, well-designed and rigorously conducted trials are needed. These trials must have clearly defined goals and must be sufficiently sized and performed so as to withstand intensive outcomes assessment. Toward this end, this document provides guidelines and definitions for the design, conduct, evaluation, and reporting of renal artery revascularization RCTs. In addition, areas of critically necessary renal artery revascularization investigation are identified. It is hoped that this information will be valuable to the investigator wishing to conduct research in this important area.

Indwelling Bouble-J Ureteral Stents for Temporary and Permanent Urinary Drainage: Experience With 87 Patients

Indwelling ureteral stents are a useful addition to the urologic armamentarium. The current double-J ureteral stent offers the advantages of ease of endoscopic insertion, exceptional patient tolerance and improved resistance to incrustation. We used these stents in 87 patients: to bypass obstruction in 57, as an adjunct to complicated upper tract surgery in 15, as initial treatment of upper urinary fistulas in 10 and for miscellaneous reasons in 5. The majority of the stents were placed endoscopically (58 per cent) and under local anesthesia (54 per cent). Half of the urinary fistulas healed without an operation and none of the patients treated with stents for malignant obstruction was hospitalized for more than 4 days. The stents were changed easily on an outpatient basis under local anesthesia and patient tolerance was excellent. When used as adjuncts to open procedures the stents frequently allowed for shorter hospital stay, since postoperative urinary drainage was decreased markedly. Of the 136 stents used in our series 13 became obstructed, usually after they were indwelling for more than 8 weeks. Irritative symptoms were noted in only 6 patients and responded well to pharmacologic therapy. We have found the double-J ureteral stent useful and reliable in patients with ureteral obstruction, as adjuncts to genitourinary surgery in selected instances and as internal diversion for upper urinary tract fistulas.

Carotid stenting and angioplasty: A statement for healthcare professionals from the councils on cardiovascular radiology, stroke, cardio-thoracic and vascular surgery, epidemiology and prevention, and clinical cardiology, american heart association

Carotid artery stenosis, particularly involving the origin of the internal carotid artery, is a frequent clinical problem. These stenoses, almost invariably atherosclerotic, can present as asymptomatic bruits discovered on physical examination, one or more transient ischemic attacks related to embolization of thrombus from stenotic lesions or to hypoperfusion, or less commonly, as an ischemic stroke. From the results of three high-quality prospective randomized trials,1 2 3 it has become apparent that symptomatic stenoses that narrow the diameter of the carotid artery more than 60% to 70% lead to a significant incidence of stroke if treated medically. The risk of stroke associated with such a lesion in symptomatic patients treated with antiplatelet therapy alone is thought to be 26%.3 With carotid endarterectomy and aspirin, this risk is lowered to 9%, a statistically significant difference.3 In patients with or without symptoms who have a stenosis ≤60%, the effectiveness of either medical therapy or carotid endarterectomy in preventing significant neurological events is not known. In symptomatic patients with <30% stenosis, medical therapy is superior to surgical therapy.2 Studies attempting to define the benefit of therapy in symptomatic patients with <60% stenosis are currently under way. Accrual of patients has slowed, however, because data show clear efficacy in symptomatic patients with stenoses ≥70%, leading to a bias toward surgery in symptomatic patients with less severe stenoses. In general the role of surgery for asymptomatic stenosis remains controversial, with some recent opinions suggesting that it may not be indicated.4 In one high-quality trial with selected experienced surgeons, there was a modest reduction in absolute risk in asymptomatic patients with stenosis ≥60%, but the significance of this finding has been debated.5 6 nnAlthough mortality associated with conventional antiplatelet therapy has been minimal,7 surgery clearly has significant perioperative morbidity and …

Atherosclerotic Vascular Disease Conference Writing Group VI: Revascularization

Revascularization has changed dramatically over the last 2 decades, with the use of percutaneous interventional techniques both replacing much of what was done with open surgery and increasing the number of patients with noncoronary atherosclerotic disease who are treated. Despite major advances, many questions remain, partly because of the continuing evolution of tools and techniques and partly because of the paucity of large prospective randomized trials. This section reviews recent advances, addresses areas of concern, and focuses primarily on the current status of catheter-based vascular interventions for atherosclerotic vascular diseases.

Carotid Stenting and Angioplasty: A Statement for Healthcare Professionals from the Councils on Cardiovascular Radiology, Stroke, Cardiovascular Surgery, Epidemiology and Prevention, and Clinical Cardiology, American Heart Association

Carotid artery stenosis, particularly involving the origin of the internal carotid artery, is a frequent clinical problem. These stenoses, almost invariably atherosclerotic, can present as asymptomatic bruits discovered on physical examination, one or more transient ischemic attacks related to embolization of thrombus from stenotic lesions or to hypoperfusion, or less commonly, as an ischemic stroke. From the results of three high-quality prospective randomized trials,1-3 it has become apparent that symptomatic stenoses that narrow the diameter of the carotid artery more than 60% to 70% lead to a significant incidence of stroke if treated medically. The risk of stroke associated with such a lesion in symptomatic patients treated with antiplatelet therapy alone is thought to be 26%.3 With carotid endarterectomy and aspirin, this risk is lowered to 9%, a statistically significant difference.3 In patients with or without symptoms who have a stenosis #60%, the effectiveness of either medical therapy or carotid endarterectomy in preventing significant neurological events is not known. In symptomatic patients with ,30% stenosis, medical therapy is superior to surgical therapy.2 Studies attempting to define the benefit of therapy in symptomatic patients with ,60% stenosis are currently under way. Accrual of patients has slowed, however, because data show clear efficacy in symptomatic patients with stenoses

Transjugular intrahepatic portosystemic shunt with an autologous vein-covered stent: results in a swine model.

70%, leading to a bias toward surgery in symptomatic patients with less severe stenoses. In general the role of surgery for asymptomatic stenosis remains controversial, with some recent opinions suggesting that it may not be indicated.4 In one high-quality trial with selected experienced surgeons, there was a modest reduction in absolute risk in asymptomatic patients with stenosis

The Working Group Report on Science-Based Categories for Abstracts Submitted to the Annual Scientific Sessions

60%, but the significance of this finding has been debated.5,6 Although mortality associated with conventional antiplatelet therapy has been minimal,7 surgery clearly has significant perioperative morbidity and mortality. This risk varies as a function of the skill and experience of the surgeon and ancillary personnel. In one large study of symptomatic patients,3 surgical complication rates were 0.6% mortality; 5.5% perioperative cerebrovascular events; and 2.1% major stroke. By contrast, over the same 32-day observation period, patients treated medically had a 0.3% fatality rate, a 3.3% risk of a cerebrovascular event, and a 0.9% risk of a major event. In a recent review of the published literature, risk of stroke and/or death following carotid endarterectomy in symptomatic patients was found to be 5.6%, although there was substantial variation in incidence as a function of the type of study and the nature of postoperative evaluation and surveillance.8 Surgery, then, in this symptomatic group of patients with significant carotid artery stenosis has a low but significant incidence of periprocedural complications. More importantly, however, according to actuarial analysis, by 2 years the risk of an ipsilateral stroke was 9% for surgical patients and 26% for medically treated patients, a 17% reduction in absolute risk with surgery.3 Since its development by Gruentzig9 in the early 1970s, use of balloon angioplasty for treatment of atherosclerotic and other vascular stenoses has gained wide acceptance. In many trials involving many organ systems, percutaneous transluminal angioplasty (PTA) has been shown to be effective. Despite several large studies, however, there is still debate about its relative efficacy and applicability compared with surgery, primarily because long-term patency after PTA is limited by restenosis as well documented in coronary, renal, and peripheral applications.10-12 Vascular stents have gained wide popularity over the last several years. There are many types with different characteristics, in different stages of clinical use and FDA approval. More

The Working Group Report on Science-Based Categories for Abstracts: Submitted to the Annual Scientific Sessions

PURPOSEnTo investigate the feasibility, safety, and efficacy of an autologous vein-covered stent (AVCS) to prevent shunt stenosis in a porcine transjugular intrahepatic portosystemic shunt (TIPS) model.nnnMATERIALS AND METHODSnTIPS were created with an AVCS in 12 healthy domestic swine and with a bare stent in 10 additional swine. Tissue response was compared with use of venography, histology, and computerized morphometry analysis 2 weeks after implantation. Differences between AVCS and noncovered stents (established by a t-test), as well as regional differences within a single stent (established by an f test), were considered significant at P <.05.nnnRESULTSnTwenty of 22 TIPS procedures were technically successful. Ten of 12 shunts with an AVCS (83%) and two of 10 with bare stents (20%) remained patent (<50% diameter narrowing) at euthanasia 2 weeks later (P <.01). Histologic evaluation of harvested bare stents showed marked intimal hyperplasia (IH), composed of smooth muscle cells, myofibroblasts, and fibroblasts. In contrast, the AVCS were remarkably free of IH and thromboses. In patent TIPS in both groups, endothelial coverage of the luminal surface was present histologically. IH accounted for 57% (26.27/45.79) of total stent cross-sectional lumen area in the control group and 21% (8.34/39.54) in the AVCS group (P <.01), with no intrashunt differences (P >.05).nnnCONCLUSIONnBased on short-term follow-up, AVCS significantly improved TIPS patency by prevention of both IH and in-stent thrombosis. TIPS created with an AVCS was feasible and safe in our porcine model.