Lower-extremity pressure, staging, and grading thresholds to identify chronic limb-threatening ischemia.

INTRODUCTION: The Society for Vascular Surgery Threatened Limb Classification System ('WIfI') is used to predict risk of limb loss and identify peripheral artery disease in patients with foot ulcers or gangrene. We estimated the diagnostic sensitivity of multiple clinical and noninvasive arterial parameters to identify chronic limb-threatening ischemia (CLTI). METHODS: We performed a single-center review of 100 consecutive patients who underwent angiography for foot gangrene or ulcers. WIfI stages and grades were determined for each patient. Toe, ankle, and brachial pressure measurements were performed by registered vascular technologists. CLTI severity was characterized using Global Limb Anatomic Staging System (GLASS stages) and angiosomes. Medial artery calcification in the foot was quantified on foot radiographs. RESULTS: GLASS NA (not applicable), I, II, and III angiographic findings were seen in 21, 21, 23, and 35 patients, respectively. A toe-brachial index < 0.7 and minimum ipsilateral ankle-brachial index < 0.9 performed well in identifying GLASS II and III angiographic findings, with sensitivity rates 97.8% and 91.5%, respectively. The diagnostic accuracy rates of noninvasive measures peaked at 74.7% and 89.3% for identifying GLASS II/III and GLASS I+ angiographic findings, respectively. The presence of medial artery calcification significantly diminished the sensitivity of most noninvasive parameters. CONCLUSIONS: The use of alternative noninvasive arterial testing parameters improves sensitivity for detecting PAD. Abnormal noninvasive results should suggest the need for diagnostic angiography to further characterize arterial anatomy of the affected limb. Testing strategies with better accuracy are needed.

Transcatheter Aortic Valve Replacement in a Young Patient With Mandibuloacral Dysplasia.

A young woman with mandibuloacral dysplasia, a syndrome on the progeria spectrum with accelerated vascular calcification and calcific valve stenosis, presented with symptomatic severe aortic stenosis. She underwent transcatheter aortic valve replacement with a balloon-expandable valve, and her exertional symptoms improved significantly. (Level of Difficulty: Intermediate.).

Comparison of different exercise ankle pressure indices in the diagnosis of peripheral artery disease.

Although the resting ankle-brachial index (ABI) is commonly used as a tool to diagnose peripheral artery disease (PAD), several additional indices measured after exercise may have increased sensitivity for identifying PAD. The aim of this study was to determine the utility of resting ABI and three post-exercise physiological parameters for diagnosing PAD confirmed by arterial imaging studies. For each qualifying study, we assessed the performance measures for identifying PAD for resting ABI < 0.90, exercise ABI < 0.90, a decrease in ABI > 20% with exercise, and a decrease in ankle pressure > 30 mmHg with exercise. Of the 199 exams that met our inclusion criteria, imaging showed a > 75% stenotic lesion in at least one limb in 138 (69%) of patients. For stenoses > 75%, resting ABI < 0.90 had a sensitivity of 64% (95% CI: 56-72%) and exercise ABI < 0.90 had a sensitivity of 88% (95% CI: 82-93%). The sensitivity for a post-exercise ABI decrease > 20% was 67% (95% CI: 59-75%) and the sensitivity for a decrease in ankle pressure > 30 mmHg was 4% (95% CI: 2-9%). For individuals with a normal resting ABI but stenotic lesions > 75% confirmed by imaging (n=49), the addition of exercise ABI testing correctly identified an additional 25% of this population. Overall, exercise ABI < 0.90 exhibits a greater sensitivity for detecting PAD compared to resting ABI. Furthermore, exercise ABI < 0.90 had added clinical utility in patients with normal resting ABIs and was superior to other commonly used exercise indices.

ACR Appropriateness Criteria® Abdominal Aortic Aneurysm: Interventional Planning and Follow-Up.

Abdominal aortic aneurysms (AAAs) are a relatively common vascular problem that can be treated with either open, surgical repair or endovascular aortic aneurysm repair (EVAR). Both approaches to AAA repair require dedicated preoperative imaging to minimize adverse outcomes. After EVAR, cross-sectional imaging has an integral role in confirming the successful treatment of the AAA and early detection of complications related to EVAR. CT angiography is the primary imaging modality for both preoperative planning and follow-up after repair. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Sudden Onset of Cold, Painful Leg.

Acute limb ischemia (ALI) requires urgent diagnosis and treatment to prevent limb loss. Invasive digital subtraction arteriography (DSA) is the gold standard for diagnosing ALI. DSA is the only diagnostic modality that permits simultaneous treatment of acute arterial occlusion. Noninvasive imaging with MRA or CT angiography may also be appropriate before treatment, especially when the diagnosis of ALI is in doubt or where DSA is unavailable. Other imaging and noninvasive physiologic tests may prove important for longer term management but are less recommended in the acute setting. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Vascular Claudication-Assessment for Revascularization.

Vascular claudication is a symptom complex characterized by reproducible pain and weakness in an active muscle group due to peripheral arterial disease. Noninvasive hemodynamic tests such as the ankle brachial index, toe brachial index, segmental pressures, and pulse volume recordings are considered the first imaging modalities necessary to reliably establish the presence and severity of arterial obstructions. Vascular imaging is consequently used for diagnosing individual lesions and triaging patients for medical, percutaneous, or surgical intervention. Catheter angiography remains the reference standard for imaging the peripheral arteries, providing a dynamic and accurate depiction of the peripheral arteries. It is particularly useful when endovascular intervention is anticipated. When combined with noninvasive hemodynamic tests, however, noninvasive imaging, including ultrasound, CT angiography, and MR angiography, can also reliably confirm or exclude the presence of peripheral arterial disease. All modalities, however, have their own technical limitations when classifying the location, extent, and severity of disease. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer-reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Bridging Experience With Eptifibatide After Stent Implantation.

BACKGROUND: Patients who have undergone intracoronary stent implantation often require surgery within the first year after the procedure. Planned or emergent surgical intervention requires interruption of antiplatelet therapy and is associated with an increased risk of stent thrombosis. Eptifibatide, an intravenous glycoprotein IIb/IIIa inhibitor (GPIIb/IIIa), can be considered for antiplatelet bridging of high-risk patients in the periprocedural period. OBJECTIVES: The aim of this report is to describe the management of antiplatelet therapy and outcomes of patients who were bridged with eptifibatide perioperatively within 1 year of intracoronary stent implantation. METHODS: We performed a retrospective analysis of patients identified through the hospital's computer system consecutively from January 1, 2011 to December 31, 2014. We included 18 patients who were bridged from an oral P2Y12-receptor antagonist with eptifibatide before surgery. Outcome measures were the incidence of thromboembolic events or stent thrombosis within 30 days of surgery and death within 90 days of hospital discharge. Safety measures were the incidence of thrombolysis in myocardial infarction major, minor, or minimal bleeding. RESULTS: Of the 18 patients assessed, no patients experienced thromboembolic events or stent thrombosis. There was one major bleeding event and one minimal bleeding event postoperatively. Antiplatelet therapy management was highly variable in the perioperative period with 72.2% receiving the recommended GPIIb/IIIa loading dose, 50% of patients not continuing aspirin throughout the surgery, 27.8% of patients stopping antiplatelet therapy less than 5 days before surgery, and 50% not receiving a loading dose of an oral P2Y12-receptor antagonist postoperatively. CONCLUSIONS: Within a limited sample size, bridging with an intravenous GPIIb/IIIa inhibitor appeared feasible. Further study is needed on the optimal strategy to manage patients with recent stenting who need surgical procedures.

ACR Appropriateness Criteria Clinically Suspected Pulmonary Arteriovenous Malformation.

Pulmonary arteriovenous malformations are often included in the differential diagnosis of common clinical presentations, including hypoxemia, hemoptysis, brain abscesses, and paradoxical stroke, as well as affecting 30% to 50% of patients with hereditary hemorrhagic telangiectasia (HHT). Various imaging studies are used in the diagnostic and screening settings, which have been reviewed by the ACR Appropriateness Criteria Vascular Imaging Panel. Pulmonary arteriovenous malformation screening in patients with HHT is commonly performed with transthoracic echocardiographic bubble study, followed by CT for positive cases. Although transthoracic echocardiographic bubble studies and radionuclide perfusion detect right-to-left shunts, they do not provide all of the information needed for treatment planning and may remain positive after embolization. Pulmonary angiography is appropriate for preintervention planning but not as an initial test. MR angiography has a potential role in younger patients with HHT who may require lifelong surveillance, despite lower spatial resolution compared with CT. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Comparative Effectiveness of Carotid Artery Stenting Versus Carotid Endarterectomy Among Medicare Beneficiaries.

BACKGROUND: Effectiveness of carotid artery stenting (CAS) relative to carotid endarterectomy (CEA) among Medicare patients has not been established. We compared effectiveness of CAS versus CEA among Medicare beneficiaries. METHODS AND RESULTS: We linked Medicare data (2000-2009) to the Society for Vascular Surgery's Vascular Registry (2005-2008) and the National Cardiovascular Data Registry's (NCDR) Carotid Artery Revascularization and Endarterectomy Registry (2006-2008/2009). Medicare patients were followed up from procedure date until death, stroke/transient ischemic attack, periprocedural myocardial infarction, or a composite end point for these outcomes. We derived high-dimensional propensity scores using registry and Medicare data to control for patient factors and adjusted for provider factors in a Cox regression model comparing CAS with CEA. Among 5254 Society for Vascular Surgery's Vascular Registry (1999 CAS; 3255 CEA) and 4055 Carotid Artery Revascularization and Endarterectomy Registry (2824 CAS; 1231 CEA) Medicare patients, CAS patients had a higher comorbidity burden and were more likely to be at high surgical risk (Society for Vascular Surgery's Vascular Registry: 96.7% versus 44.5%; Carotid Artery Revascularization and Endarterectomy Registry: 71.3% versus 44.7%). Unadjusted outcome risks were higher for CAS. Mortality risks remained elevated for CAS after adjusting for patient-level factors (hazard ratio, 1.24; 95% confidence interval, 1.06-1.46). After further adjustment for provider factors, differences between CAS and CEA were attenuated or no longer present (hazard ratio for mortality, 1.13; 95% confidence interval, 0.94-1.37). Performance was comparable across subgroups defined by sex and degree of carotid stenosis, but there was a nonsignificant trend suggesting a higher risk of adverse outcomes in older (>80) and symptomatic patients undergoing CAS. CONCLUSIONS: Outcomes after CAS and CEA among Medicare beneficiaries were comparable after adjusting for both patient- and provider-level factors.

Noninvasive Monitoring of Immune Rejection in Face Transplant Recipients.

BACKGROUND: Chronic rejection leading to allograft loss remains a significant concern after facial allotransplantation. Chronic rejection may occur without clinical signs or symptoms. The current means of monitoring is histologic analyses of allograft biopsy specimens, which is both invasive and impractical. Prior data suggest that chronic rejection is associated with changes in intima and media thickness of vessels in arms and solid organ allografts; such data have not been published for face transplant recipients. METHODS: The authors used a 48-MHz transducer to acquire images of the bilateral facial, radial, dorsalis pedis and, if applicable, sentinel flap arteries in five face transplant recipients (8 months to 4.5 years after transplantation) and five control subjects. The authors assessed the intima, media, and adventitia thickness plus lumen and the total vessel diameter and area. RESULTS: Face transplant recipients had thicker intima in all sites compared with controls, but the ratio of the intimal thickness of facial and radial arteries was similar in face transplant recipients compared with controls (1.00 versus 0.95; p = 0.742). Intraobserver correlation showed reliable reproducibility of the measurements (r = 0.935, p ≤ 0.001). Interobserver correlation demonstrated reproducibility of intima measurements (r = 0.422, p ≤ 0.001). CONCLUSION: The authors demonstrate that ultrasound biomicroscopy is feasible for postsurgical monitoring, and have developed a new benchmark parameter, the facial artery-to-radial artery intimal thickness ratio, to be used in future testing in the setting of chronic rejection. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, IV.

Relationship Between Physician and Hospital Procedure Volume and Mortality After Carotid Artery Stenting Among Medicare Beneficiaries.

BACKGROUND: Clinical trials demonstrated the efficacy of carotid artery stenting (CAS) relative to carotid endarterectomy when performed by physicians with demonstrated proficiency. It is unclear how CAS performance may be influenced by the diversity in CAS and non-CAS provider volumes in routine clinical practice. METHODS AND RESULTS: We linked Medicare claims to the Centers for Medicare and Medicaid Services' CAS Database (2005-2009). We assessed the association between 30-day mortality and past-year physician (0, 1-4, 5-9, 10-19, ≥20) and hospital (<10, 10-19, 20-39, ≥40) CAS volumes and past-year hospital coronary and peripheral stenting volumes (<200, 200-399, 400-849, ≥850) among beneficiaries at least 66 years of age. Unadjusted 30-day mortality risk was 1.8% (95% confidence interval [CI], 1.6-2.0) for 19 724 patients undergoing CAS by 2045 physicians in 729 hospitals. Median past-year CAS volume was 9 (interquartile range, 4-19) for physicians and 23 (interquartile range, 12-41) for hospitals. Compared to physicians performing ≥20 CAS in the past year, lower CAS volumes were associated with higher adjusted risks of 30-day morality (P value for trend < 0.05): 1.4 (95% CI, 0.9-2.3) for 0 past-year CAS, 1.3 (95% CI, 0.9-1.8) for 1 to 4, 1.1 (95% CI, 0.8-1.6) for 5 to 9, and 0.9 (95% CI, 0.7-1.4) for 10 to 19. An inverse relationship between 30-day mortality and past-year CAS hospital volume as well as past-year hospital non-CAS volume, past-year hospital non-CAS volume, and 30-day mortality was also noted. CONCLUSIONS: Among Medicare patients, an inverse relationship exists between physician and hospital CAS volumes and hospital non-CAS stenting volume and 30-day mortality, even after adjusting for all pertinent patient- and hospital-level factors.