Beau M. Hawkins

Clinical cardiac involvement in thrombotic thrombocytopenic purpura: a systematic review

BACKGROUND: Autopsy studies consistently demonstrate cardiac involvement in thrombotic thrombocytopenic purpura (TTP), but clinical evidence for cardiac abnormalities is rarely reported.

Proximal versus distal embolic protection for carotid artery stenting: a national cardiovascular data registry analysis.

OBJECTIVES The aim of this study was to compare the stroke/death rates between proximal embolic protection devices (P-EPDs) and distal filter embolic protection devices (F-EPDs) in elective carotid artery stenting (CAS). BACKGROUND P-EPDs have theoretical advantages that may make them superior to F-EPDs for stroke prevention during CAS. METHODS We examined 10,246 consecutive elective CAS procedures performed with embolic protection in the NCDR CARE registry between January 2009 and March 2013. We analyzed crude and propensity-matched rates of in-hospital combined death/stroke in patients treated with P-EPDs versus F-EPDs. Secondary analyses included 30-day adverse event rates and stroke rates by the involved cerebrovascular territory. RESULTS P-EPDs were used in 590 of 10,246 cases (5.8%). Patients treated with P-EPDs had higher rates of symptomatic lesion status (46.8% vs. 39.7%, p<0.001), atrial fibrillation/flutter (16.1% vs. 13.0%, p=0.03), and history of a neurological event (51.2% vs. 46.6%, p=0.03). In unadjusted and propensity-matched analyses, differences in in-hospital stroke/death between P-EPD and F-EPD cohorts were nonsignificant (1.5% vs. 2.4%, p=0.16 and 1.6% vs. 2.0%, p=0.56, respectively). For patients with available data (n=7,693, 75.1%), 30-day adverse events rates were similar for P-EPDs and F-EPDs before (2.5% vs. 4.2%, p=0.07) and after (2.7% vs. 4.0%, p=0.22) propensity matching. CONCLUSIONS Use of a P-EPD during CAS was associated with low rates of in-hospital stroke/death similar to those with an F-EPD in the first comparative effectiveness study of the devices. An adequately powered randomized trial comparing clinical outcomes between these devices is unlikely to be feasible.

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.

Inferior Vena Cava Filter Usage, Complications, and Retrieval Rate in Cancer Patients

BACKGROUND Venous thromboembolism contributes significantly to morbidity and mortality in cancer patients. Because cancer patients frequently have contraindications to anticoagulation, inferior vena cava filters are commonly placed. The use, safety, and retrieval of retrievable inferior vena cava filters in cancer patients have not been well studied. METHODS A retrospective review of retrievable inferior vena cava filter use at a tertiary referral hospital was conducted between January 1, 2009 and December 31, 2011. Indications for inferior vena cava filter placement, anticoagulation practices, complications, filter retrieval, and patient outcomes were analyzed for patients with and without active cancer and for cancer subtypes, including localized and metastatic cases. RESULTS Of 666 patients receiving retrievable inferior vena cava filters during this time period, 247 (37.1%) had active cancer. Of these, 151 (22.7%) had carcinoma, 92 (13.8%) had sarcoma, and 115 (17.3%) had metastatic disease. Overall, follow-up was available for a median of 401.0 (interquartile range: 107.5-786.5) days. Indwelling filter-related complications occurred in 19.8% of patients without cancer and 17.7% with an active cancer (P = .50). Patients with cancer were less likely to have the filter retrieved (28.0% vs 42.0%, P < .001). In multivariable analysis, cancer was not associated with filter-related complications but was associated with a lower rate of filter retrieval. CONCLUSIONS In a modern cohort of patients undergoing retrievable inferior vena cava filter placement, active diagnosis of cancer is not associated with a significant increase in filter-related complications, but is associated with a reduced rate of filter retrieval.

Anatomic correlates of supra‐normal ankle brachial indices

Supra‐normal ankle brachial index (ABI) (>1.40), poses diagnostic challenges to determine the presence, location, and severity of peripheral artery disease (PAD). The anatomic distribution of PAD in patients with elevated ABI has not been previously described.

Effect of delayed inferior vena cava filter retrieval after early initiation of anticoagulation.

Retrievable inferior vena cava filters (IVCFs) were designed to provide temporary protection from pulmonary embolism in high-risk situations. However, little is known about their effectiveness, and many remain permanently implanted, leading to potential complications. The aim of this study was to determine patient characteristics, indications for IVCF placement, retrieval rates, complications, and post-IVCF anticoagulation (AC) practices in patients who have received IVCFs. A retrospective review of IVCF use by 3 specialty groups from January 1, 2009, to December 31, 2011, was conducted at a tertiary referral center. Indications for IVCF, procedural success and complications, post-IVCF AC practices, and patient outcomes were assessed. Seven hundred fifty-eight IVCFs were placed. Follow-up was available for 688 patients (90.7%) at a median of 342.0 days (interquartile range 81.5 to 758.0). Indications for IVCF placement included contraindication to AC in the presence of acute venous thromboembolism (n = 287 [41.7%]) and prophylaxis (n = 235 [34.2%]). Insertion-related complications occurred in 28 patients (4.1%). After IVCF placement, adequate AC was initiated in 454 patients (66.0%) <3.0 days (interquartile range 0 to 13.0) after insertion, but the overall retrieval rate was only 252 of 688 (36.6%) within a median of 134.0 days (interquartile range 72.50 to 205.8). Significant IVCF-related complications occurred in 122 patients (17.7%) within 32 days (interquartile range 13.0 to 116.8). The most common complication (72 of 131 [55.0%]) was deep vein thrombosis. In conclusion, in a large, modern cohort of patients receiving retrievable IVCFs for a variety of indications by various specialties, IVCF insertion remains safe. However, many patients have IVCF-related complications, and often, even when IVCFs are retrieved, there is a delay between AC and retrieval. Quality improvement initiatives that facilitate the expeditious retrieval of IVCF are needed.

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.

Endovascular treatment of mesenteric ischemia

Objectives: Our goal was to describe a single‐centers experience in managing acute and chronic mesenteric ischemia with endovascular therapies.

Hospital Variation in Carotid Stenting Outcomes

OBJECTIVES The aim of this study was to examine variation in outcomes for patients receiving carotid artery stenting (CAS) across a sample of U.S. hospitals and assess the extent to which this variation was attributable to differences in case mix and procedural volume. BACKGROUND As CAS is increasingly being used throughout the United States, assessing hospital variation in CAS outcomes is critical to understanding and improving the quality of care for patients with carotid artery disease. METHODS Hospitals participating in the National Cardiovascular Data Registry-Carotid Artery Endarterectomy and Revascularization Registry contributing more than 5 CAS procedures from 2005 through 2013 were eligible for inclusion. We estimated unadjusted and risk-standardized rates of in-hospital stroke or death for each participating hospital using a previously validated prediction model and applying hospital-level random effects. RESULTS There were 188 hospitals contributing 19,381 CAS procedures during the period of interest. Unadjusted and risk-standardized in-hospital stroke or death rates ranged from 0% to 18.8% and 1.2% to 4.7%, respectively. Operator and hospital volumes were not significant predictors of outcomes after adjustment for case mix (p = 0.15 and p = 0.09, respectively). CONCLUSIONS CAS outcomes vary 4-fold among hospitals, even after adjustment for differences in case mix. Future work is needed to identify the sources of this variation and develop initiatives to improve patient outcomes.

Unprotected carotid artery stenting in modern practice

Embolic protection devices (EPD) may provide a mechanism to reduce peri‐procedural strokes. They are advocated by consensus guidelines and mandated for Medicare reimbursement. However, outcomes data remain mixed. We aimed to characterize the population of patients undergoing unprotected carotid artery stenting (CAS) and assess the utility of distal filter EPD (F‐EPD) in elective CAS.