Douglas E. Drachman

Neointimal thickening after stent delivery of paclitaxel : change in composition and arrest of growth over six months

OBJECTIVES The purpose of this study was to determine long-term effects of stent-based paclitaxel delivery on amount, rate and composition of neointimal thickening after stent implantation. BACKGROUND Paclitaxel prevents vascular smooth muscle cell proliferation and migration in vitro and in vivo. These actions, coupled with low solubility, make it a viable candidate for modulating vascular responses to injury and prolonged effects after local delivery. We asked whether local delivery of paclitaxel for a period of weeks from a stent coated with a bioerodible polymer could produce a sustained reduction in neointimal hyperplasia for up to six months after stenting. METHODS Stainless steel stents were implanted in the iliac arteries of rabbits after endothelial denudation. Stents were uncoated or coated with a thin layer of poly(lactide-co-sigma-caprolactone) copolymer alone or containing paclitaxel, 200 microg. RESULTS Paclitaxel release in vitro followed first-order kinetics for two months. Tissue responses were examined 7, 28, 56 or 180 days after implantation. Paclitaxel reduced intimal and medial cell proliferation three-fold seven days after stenting and virtually eliminated later intimal thickening. Six months after stenting, long after drug release and polymer degradation were likely complete, neointimal area was two-fold lower in paclitaxel-releasing stents. Tissue responses in paclitaxel-treated vessels included incomplete healing, few smooth muscle cells, late persistence of macrophages and dense fibrin with little collagen. CONCLUSIONS Poly(lactide-co-sigma-caprolactone) copolymer-coated stents permit sustained paclitaxel delivery in a manner that virtually abolishes neointimal hyperplasia for months after stent implantation, long after likely completion of drug delivery and polymer degradation.

2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines

Jonathan L. Halperin, MD, FACC, FAHA, Chair Glenn N. Levine, MD, FACC, FAHA, Chair-Elect Sana M. Al-Khatib, MD, MHS, FACC, FAHA Kim K. Birtcher, PharmD, MS, AACC Biykem Bozkurt, MD, PhD, FACC, FAHA Ralph G. Brindis, MD, MPH, MACC Joaquin E. Cigarroa, MD, FACC Lesley H. Curtis, PhD, FAHA

SCAI expert consensus statement for femoral-popliteal arterial intervention appropriate use

Successful endovascular intervention for femoral‐popliteal (FP) arterial disease provides relief of claudication and offers limb‐salvage in cases of critical limb ischemia. Technologies and operator technique have evolved to the point where we may now provide effective endovascular therapy for a spectrum of lesions, patients, and clinical scenarios. Endovascular treatment of this segment offers a significant alternative to surgical revascularization, and may confer improved safety for a wide range of patients, not solely those deemed high surgical risk. Although endovascular therapy of the FP segment has historically been hampered by high rates of restenosis, emerging technologies including drug‐eluting stents, drug‐coated balloons, and perhaps bio‐absorbable stent platforms, provide future hope for more durable patency in complex disease. By combining lessons learned from clinical trials, international trends in clinical practice, and insights regarding emerging technologies, we may appropriately tailor our application of endovascular therapy to provide optimal care to our patients. This document was developed to guide physicians in the clinical decision‐making related to the contemporary application of endovascular intervention among patients with FP arterial disease.

Pre-procedural Risk Quantification for Carotid Stenting Using the CAS Score: A Report From the NCDR CARE Registry

OBJECTIVES We developed and internally validated a risk score to predict in-hospital stroke or death after carotid artery stenting (CAS). BACKGROUND A tool that accurately assesses CAS risk could aid clinical decision making and improve patient selection. METHODS Patients undergoing CAS without acute evolving stroke from April 2005 through June 2011 as part of the NCDR Carotid Artery Revascularization and Endarterectomy (CARE) Registry were included. In-hospital stroke or death was modeled using logistic regression with 35 candidate variables. Internal validation was achieved with bootstrapping, and model discrimination and calibration were assessed. RESULTS A total of 271 (2.4%) primary endpoint events occurred during 11,122 procedures. Independent predictors of stroke or death included impending major surgery, previous stroke, age, symptomatic lesion, atrial fibrillation, and absence of previous ipsilateral carotid endarterectomy. The model was well calibrated with moderate discriminatory ability (C-statistic: 0.71) overall, and within symptomatic (C-statistic: 0.68) and asymptomatic (C-statistic: 0.72) subgroups. The inclusion of available angiographic variables did not improve model performance (C-statistic: 0.72, integrated discrimination improvement 0.001; p = 0.21). The NCDR CAS score was developed to support prospective risk quantification. CONCLUSIONS The NCDR CAS score, comprising 6 clinical variables, predicts in-hospital S/D after CAS. This tool may be useful to assist clinicians in evaluating optimal management, share more accurate pre-procedural risks with patients, and improve patient selection for CAS.

2016 AHA/ACC Guideline on the Management of Patients with Lower Extremity Peripheral Artery Disease: Executive Summary

Developed in Collaboration With the American Association of Cardiovascular and Pulmonary Rehabilitation, Inter-Society Consensus for the Management of Peripheral Arterial Disease, Society for Cardiovascular Angiography and Interventions, Society for Clinical Vascular Surgery, Society of Interventional Radiology, Society for Vascular Medicine, Society for Vascular Nursing, Society for Vascular Surgery, and Endovascular Surgery Society

Takotsubo Cardiomyopathy Complicated by Cardiac Tamponade Classic Hemodynamic Findings With a New Disease

An 83-year-old woman with no significant medical history developed acute onset chest pain lasting for 1 hour. Electrocardiography performed by emergency responders showed transient 2-mm high-lateral ST elevations on electrocardiography (Figure 1), and she was brought to the emergency room. She was treated with unfractionated heparin (60-U/kg bolus followed by 12 U/kg/min infusion), the glycoprotein IIb/IIIa inhibitor eptifibatide (180-μg/kg bolus followed by 2-μg · kg−1 · min−1 infusion), and 300 mg of clopidogrel by mouth. She developed severe hypotension that required high-dose parenteral inotropic support and was transferred to the catheterization laboratory for emergency cardiac catheterization. Coronary angiography revealed only minor atherosclerotic disease in a small diagonal branch; left ventriculography demonstrated akinesis of the entire mid to apical portions of the left ventricle, consistent with the “apical ballooning” syndrome, or takotsubo cardiomyopathy (Figure …

Treatment of renal artery in-stent restenosis with sirolimus-eluting stents

The objective of this study was to analyze the use of sirolimus-eluting stent (SES) placement for the treatment of renal artery in-stent restenosis (RA-ISR). The optimal treatment of RA-ISR has not been fully elucidated to date. We retrospectively analyzed consecutive patients from our institution who underwent treatment of RA-ISR with a SES from May 2004 to June 2006. Using duplex ultrasound, RA-ISR (> 60% diameter) was determined by peak systolic velocity (PSV) > 300 cm/s and renal aortic ratio (RAR) > 4.0. Renal function (creatinine) and blood pressure were measured at baseline and follow-up. SESs were implanted in 16 patients (22 renal arteries) during the study period. The study cohort was predominantly female (75%) with a mean age of 68 ± 12 years. RA-ISR was treated with SESs with a mean diameter of 3.5 mm and mean length of 17.9 ± 3.8 mm. The mean post-dilation balloon diameter was 4.8 ± 0.6. The baseline renal artery PSV was 445 ± 131 cm/s with a mean RAR of 5.0 ± 1.6. Follow-up information was available in 21 renal arteries. During a median follow-up of 12 months (range: 9—15 months), 15 renal arteries (71.4%) developed recurrence of ISR by ultrasonographic criteria. Univariate analysis revealed that female sex was an independent predictor of recurrence of ISR after SES implantation (p < 0.05). In conclusion, placement of a SES for the treatment of ISR in renal arteries is associated with high initial technical success but significant restenosis on duplex ultrasonography at follow-up.

Comparative Effectiveness of Commonly Used Devices for Carotid Artery Stenting: An NCDR Analysis (National Cardiovascular Data Registry)

OBJECTIVES This study sought to characterize usage and outcomes of carotid stenting platforms. BACKGROUND A variety of stents and embolic protection devices (EPDs) are used for carotid artery stenting. Little is known about current usage patterns and differences in outcomes with these devices. METHODS We analyzed 12,135 consecutive carotid stent procedures in the NCDR (National Cardiovascular Data Registry) CARE (Carotid Artery Revascularization and Endarterectomy) registry performed between January 1, 2007 and March 31, 2012. We compared baseline characteristics and crude and multivariable-adjusted rates of in-hospital combined death/stroke among patients treated with Acculink/Accunet (Abbott Laboratories, Abbott Park, Illinois), Xact/Emboshield (Abbott), and Precise/Angioguard (Cordis Corporation, Bridgewater, New Jersey) stent/EPD combinations. RESULTS In 78.2% of cases, stents were used in conjunction with their specific, corresponding U.S. Food and Drug Administration-approved EPD. The Acculink/Accunet (n = 2,617, 21.6%), Xact/Emboshield (n = 3,507, 28.9%), and Precise/Angioguard (n = 2,696, 22.2%) stent/EPD combinations were used in 72.7% of all cases. The Protégé/SpiderFx (ev3 Endovascular Inc., Plymouth, Minnesota) (n = 453, 3.7%) and Wallstent/Filterwire (Boston Scientific, Natick, Massachusetts) (n = 213, 1.8%) devices were used in a minority of cases. In unadjusted analyses, the Precise/Angioguard system was associated with higher rates of the primary outcome than were the Acculink/Accunet (2.5% vs. 1.8%; p = 0.058) and Xact/Emboshield (2.5% vs. 1.9%; p = 0.14) systems that were not statistically different. In adjusted analyses, differences between Precise/Angioguard and Accunet/Acculink (odds ratio [OR]: 1.48, 95% confidence interval [CI]: 0.89 to 2.47; p = 0.065), Precise/Angioguard and Xact/Emboshield (OR: 1.16, 95% CI: 0.77 to 1.76; p = 0.38), and Xact/Emboshield and Accunet/Acculink (OR: 1.28, 95% CI: 0.82 to 1.97; p = 0.18) remained nonsignificant. CONCLUSIONS In modern U.S. practice, the Acculink/Accunet, Xact/Emboshield, and Precise/Angioguard carotid stenting systems are used in most cases and are associated with similarly low rates of adverse events.

Drug-Eluting Stents in Animals and Patients Where Do We Stand Today?

Four legs good, two legs better. — —George Orwell, Animal Farm, 1945 Since the earliest use of coronary stents for treating symptomatic coronary stenosis, maintaining patent arteries after treatment has remained an elusive goal. Although the first bare metal stents opened stenotic arteries, they injured the arterial wall. The buildup of intimal scar tissue caused restenosis, a frustrating problem for prevention or treatment. After a dozen years of research, however, drug-eluting stents were developed; armed with polymer coating and paclitaxel or sirolimus, they prevented restenosis and were hailed as a major therapeutic breakthrough. Article see p 141 Not long afterward, however, questions about the safety and efficacy of drug-eluting stents surfaced as reports of late stent thrombosis began to appear.1,2 Cardiologists wondered if prevention of restenosis was always a good thing. If no protective cellular layer formed over the struts of the drug-eluting stent—even months or years after implantation—would thrombus develop on the exposed metal scaffolding or other damaged or inflamed areas on the blood vessel wall? Over months or years, would progressive inflammation or late “catchup” tissue growth cause drug-eluting stents to lose their early advantage over bare metal stents? The pendulum in this debate has swung back and forth as clinical trials first raised concern about increased thrombosis and then later quelled our fears as our understanding of how drug-eluting stents work in real life has matured. An important issue has been the increased use of stents in patients with more complex coronary and other disorders, raising the question of whether the established standards of safety and efficacy still apply. Answers for these challenging questions have come from 2 worlds: clinical studies of patients with stents …

Efficacy and safety of argatroban in patients with heparin induced thrombocytopenia undergoing endovascular intervention for peripheral arterial disease

Objectives: This study aimed to evaluate the efficacy and safety of argatroban during percutaneous interventions for peripheral arterial disease (PAD). Background: Endovascular interventions are commonly used in patients with peripheral arterial disease. Heparin is routinely administered during these procedures, but cannot be used in patients with a history of heparin‐induced thrombocytopenia (HIT). Argatroban is an approved direct thrombin inhibitor for treatment of patients with HIT. There are currently few data on the efficacy and safety of argatroban during endovascular interventions for PAD. Methods: Patients who underwent endovascular interventions for PAD on argatroban between 2002 and 2005 were identified from out database. Efficacy was evaluated using a composite of death, urgent revascularization, and amputation, while safety was assessed by TIMI major bleeding during the index hospitalization. Results: A total of 48 patients undergoing lower extremity revascularization on argatroban were identified. Thirty two of these patients (67%) had antibody‐confirmed HIT and the other 16 (33%) had suspected HIT. A mean dose of argatroban was 173.5 ± 143 μg/kg bolus, followed by a 10.7 ± 9.64 μg/kg/min infusion during the procedure. Twelve patients (25%) met the composite end point (two deaths, one urgent revascularization, nine amputations because of progressive peripheral arterial disease). TIMI major bleeding occurred in three (6%) patients. Conclusion: In patients with confirmed or suspected HIT undergoing endovascular intervention for PAD, argatroban appears to be effective and safe. A larger study is warranted to confirm these findings from a single center.