Edgar Luis Galiñanes

Endovascular versus open repair of popliteal artery aneurysms: outcomes in the US Medicare population.

Objective: The management of popliteal artery aneurysms (PAAs) has undergone significant transition from open surgery to endovascular graft placement with few longitudinal data evaluating outcomes. Methods: The Centers of Medicare & Medicaid Services Inpatient claims (2005-2007) were queried with a diagnosis of lower extremity artery aneurysm in association with elective Current Procedural Terminology codes for open (OPEN group) and endovascular (ENDO group) repair. Results: A total of 2962 patients were identified. Endovascular interventions significantly increased over the time of the study (11.7% vs 23.6%, P < .0001). Overall complication rates for OPEN and ENDO groups did not differ significantly (11.3% vs 9.3%; P = .017). No differences in the 30- and 90-day mortality rates were found between OPEN versus ENDO groups. The ENDO group had greater 30- and 90-day reinterventions (4.6% vs 2.1%, P = .001 and 11.8% vs 7.4%, P = .0007, respectively). Length of stay (4.5 days vs 2.5 days, P < .0001) and charges (

Inward remodeling of resistance arteries requires reactive oxygen species-dependent activation of matrix metalloproteinases

43 180 vs

Prolonged vasoconstriction of resistance arteries involves vascular smooth muscle actin polymerization leading to inward remodelling

35 540, P < .0001) were greater for OPEN group. Conclusion: Despite a significant increase in the utilization of endovascular repair of PAAs, endovascular repair was associated with greater reinterventions over time and did not offer a mortality or cost benefit.

The impact of preoperative statin therapy on open and endovascular abdominal aortic aneurysm repair outcomes.

Inward eutrophic remodeling is the most prevalent structural change of resistance arteries in hypertension. Sympathetic and angiotensin (ANG)-induced vasoconstriction has been associated with hypertension and with the production of matrix metalloproteinases (MMPs) and ROS. Therefore, we hypothesize that prolonged exposure to norepinephrine (NE) and ANG II induces arteriolar inward remodeling dependent on the activation of MMPs and the production of ROS. This hypothesis was tested on rat cremaster arterioles that were isolated, cannulated, pressurized, and exposed to either NE (10(-5.5) mol/l) + ANG II (10(-7) mol/l) or vehicle (control) for 4 h. The prolonged exposure to NE + ANG II induced inward remodeling, as evidenced by the reduced maximal arteriolar passive diameter observed after versus before exposure to the vasoconstrictor agonists. NE + ANG II also increased the arteriolar expression and activity of MMP-2 and the production of ROS as determined, respectively, by real-time RT-PCR, gel and in situ zymography, and the use of ROS-sensitive dyes with multiphoton microscopy. Inhibition of MMP activation (with GM-6001) or ROS production (with apocynin or tempol) prevented the NE + ANG II-induced inward remodeling. Inhibition of ROS production prevented the activation of MMPs and the remodeling process, whereas inhibition of MMP activation did not affect ROS production. These results indicate that prolonged stimulation of resistance arterioles with NE + ANG II induces a ROS-dependent activation of MMPs necessary for the development of arteriolar inward remodeling. These mechanisms may contribute to the structural narrowing of resistance vessels in hypertension.

Thoracic Mural Thrombi: A Case Series and Literature Review

AIMS Inward remodelling of the resistance vasculature is predictive of hypertension and life-threatening cardiovascular events. We hypothesize that the contractile mechanisms responsible for maintaining a reduced diameter over time in response to prolonged stimulation with vasoconstrictor agonists are in part responsible for the initial stages of the remodelling process. Here we investigated the role of vascular smooth muscle (VSM) actin polymerization on agonist-induced vasoconstriction and development of inward remodelling. METHODS AND RESULTS Experiments were conducted in Sprague-Dawley rat resistance vessels isolated from the cremaster and mesentery. Within blood vessels, actin dynamics of VSM were monitored by confocal microscopy after introduction of fluorescent actin monomers through electroporation and by differential centrifugation to probe globular (G) and filamentous (F) actin content. Results indicated that 4 h of agonist-dependent vasoconstriction induced inward remodelling and caused significant actin polymerization, elevating the F-/total-actin ratio. Inhibition of actin polymerization prevented vessels from maintaining prolonged vasoconstriction and developing inward remodelling. Activation of the small GTPases Rho/Rac/Cdc42 also increased the F-/total-actin ratio and induced inward remodelling, while inhibition of Rho kinase or Rac-1 prevented inward remodelling. Disruption of the actin cytoskeleton reversed the inward remodelling caused by prolonged vasoconstriction, but did not affect the passive diameter of freshly isolated vessels. CONCLUSION These results indicate that vasoconstriction-induced inward remodelling is in part caused by the polymerization of actin within VSM cells through activation of small GTPases.

Evaluation of Readmission Rates for Carotid Endarterectomy Versus Carotid Artery Stenting in the US Medicare Population

Objectives This study evaluated the utilization of preoperative statins and their impact on perioperative outcomes in patients undergoing open or endovascular aortic repair. Methods Patients ≥50 years of age with non-ruptured abdominal aortic aneurysm repair were identified in MedPAR files 2007–2008 utilizing ICD-9-CM codes. Preoperative statins use was identified using National Drug Codes in Part D. Chi-square test, multivariable logistic regression, Kaplan-Meier and Cox regression modeling were performed. Results In all, 19,323 patients were identified undergoing abdominal aortic aneurysm repair (14,602 endovascular aortic repair and 4721 open aortic repair); 9913 (50.3%) used statins before surgery. Bivariate analysis demonstrated lower rates of hospital, 30-, 90-day and 1-year mortality in patients with statins compared to those without statins after endovascular aortic repair (1.0% vs. 1.45%, p = 0.01; 1.51% vs. 2.3%, p = 0.0004; 3.05% vs. 4.66%, p < 0.0001; 7.91% vs. 11.56%, p < 0.0001, respectively). Multivariable logistic regression adjusting for age, gender, race, comorbidities and procedure demonstrated preoperative statins use was associated with a mortality reduction at 90-days postoperatively (odds ratio = 0.80; 95% CI 0.70–0.91, p = 0.0014) and 1-year postoperatively (odds ratio = 0.76; 95% CI 0.69–0.84, p = 0.0001). Conclusions Only half of the patients undergoing abdominal aortic aneurysm repair were prescribed preoperative statins. After adjustment, statins were significantly associated with improved survival during 1 year after surgery and a decreased incidence of lower extremity embolic complications after endovascular aortic repair. These data support a beneficial role of statin use prior to surgery for patients undergoing abdominal aortic aneurysm repair. Further prospective studies are needed to assess the benefit of statins in the perioperative period after 365 days.

Routine revascularization is unnecessary in the majority of patients requiring zone II coverage during thoracic endovascular aortic repair: a longitudinal outcomes study using United States Medicare population data.

Thoracic mural thrombi (TMT) are rare but an important source of distal emboli. Treatment options are dynamic, ranging from open, endovascular to conservative therapies. We report two cases of TMT, one successfully treated with thoracic aortic endoluminal stent placement for visceral and peripheral embolization, the second treated conservatively for digital embolization secondary to TMT in the innominate artery.

Longitudinal outcomes after tibioperoneal angioplasty alone compared to tibial stenting and atherectomy for critical limb ischemia.

Objective: We evaluated rates and identified predictors of readmission in the Medicare population after carotid endarterectomy (CEA) compared to carotid artery stenting (CAS). Methods: MedPAR data (2005-2009) were used to select patients who underwent CEA or CAS (utilizing International Classification of Diseases, Ninth Revision, Clinical Modification codes). Readmission was evaluated using chi-square and multivariable logistic regression. Results: A total of 235 247 carotid interventions were performed (211 118 CEA and 24 129 CAS). Readmission rates (%) for patients undergoing CEA and CAS, respectively, were 8.84 and 11.11 (30 days; P < .0001); 13.31 and 17.98 (60 days; P < .0001); and 16.86 and 22.68 (90 days; P < .0001). Patients aged >80 (odds ratio [OR] = 1.25; 95% confidence interval [CI] = 1.20-1.30) and patients with renal failure (OR = 1.6 95%; CI = 1.56-1.73), congestive heart failure (OR = 1.6; 95%CI = 1.57-1.73), diabetes (OR = 1.4; 95% CI 1.27-1.52), and CAS (OR = 1.2; 95%CI = 1.15-1.25) were more likely to be readmitted. Conclusions: Interventions for carotid artery disease had high overall readmission rates. After adjustment for comorbidities, utilization of less invasive techniques (CAS) did not result in lower readmission rates. Further evaluation is needed to determine strategies to reduce hospital readmission rates after carotid interventions.

Clopidogrel and 1-year freedom from amputation after endovascular lower extremity revascularization in the Medicare population.

Objective We aimed to evaluate outcomes of thoracic endovascular aortic repair (TEVAR) with left subclavian artery (LSA) coverage without bypass (TEVAR + SUB) to TEVAR with coverage of the LSA with a bypass at the time of the initial procedure or later at a separate procedure (TEVAR + SUB + BYPASS). Methods The Centers for Medicare & Medicaid Services inpatient claims for 2006–2007 were queried using Current Procedural Terminology codes for TEVAR, TEVAR + SUB, TEVAR + SUB + BYPASS or later as a separate procedure. Results A total of 2676 patients underwent TEVAR; 869 (32.5%) underwent TEVAR + SUB and 49 (5.6%) TEVAR + SUB + BYPASS. At the time of the initial procedure, TEVAR + SUB + BYPASS was associated with a higher incidence of stroke compared to TEVAR + SUB (12.8% vs. 3.8 %; p = 0.0033). Among TEVAR + SUB, only 1.93% (50 patients) had a subsequent bypass performed during a one-year follow-up. Overall rates of morbidity (p = 0.004) and mortality (p = 0.011) trended towards significance in favor of TEVAR + SUB. Conclusions TEVAR + SUB were associated with lower rates of mortality and complications. Only a small percentage of TEVAR + SUB required a bypass at one year after procedure. Our data suggest that routine LSA bypass during TEVAR is unnecessary and associated with increase morbidity and mortality.

IP153. Preliminary Results With Drug-Eluting Balloon for the Treatment of Venous Outflow Stenosis of Arteriovenous Fistulas and Grafts

Objectives: There are limited data available evaluating longitudinal outcomes after tibioperoneal angioplasty (TA) alone compared to adjunctive tibial procedures including stenting and atherectomy. Methods: Using the Centers for Medicare & Medicaid Services inpatient claims (2005-2007), patients evaluated TA only, TA plus stent placement (TA + S), and TA plus atherectomy (TA + A). Results: A total of 2080 patients with critical limb ischemia underwent percutaneous tibioperoneal intervention for the indication of ulceration. Procedures included TA (56.3%), TA + S (16.2%), and TA + A (27.5%). Rates of amputation were not statistically different between the groups at 30, 90, and 365 days after the intervention. Mean total hospital charges were TA (