Ronald M Fairman

University of Pennsylvania, Philadelphia, Pennsylvania, United States

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Publications (176)431.48 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Endovascular treatment of abdominal aortic aneurysm (AAA) is associated with benefits over open surgery, yet limitations remain with current endovascular devices. This study was performed to assess outcomes of AAA repair with the Aptus endograft and EndoAnchors (Aptus Endosystems, Sunnyvale, Calif).
    Journal of vascular surgery. 08/2014; 60(2):275-285.
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    ABSTRACT: Purpose To compare the durability of thoracic endovascular aortic repair (TEVAR) in two similar clinical trials that used early- and later-generation stent-grafts. Materials and Methods Secondary procedures from the prospective, nonrandomized, multicenter, clinical trial databases of the test arm of the VALOR and VALOR II trials were analyzed at 3 years. Descriptive and statistical analyses were employed to compare the rate of and potential predictors for secondary procedures. Results A total of 127 and 96 patients were available for a minimum of 3 years of follow-up in the test arm of VALOR and VALOR II, respectively. By the first year after the index procedure, VALOR II patients were significantly less likely to have undergone a secondary procedure versus patients in the test arm of VALOR (odds ratio [OR], 0.08; 95% confidence interval [CI], 0.01–0.63; P = .02), with most procedures performed for type I endoleak. Multivariate predictors at 3 years for the need for a secondary procedure in the VALOR test arm were maximum aneurysm diameter (P = .002) and aneurysm length (P = .01), both of which remained significant at the end of the study period. The estimated freedoms from secondary procedures in the VALOR test arm and VALOR II at 3 years were 85.1% (95% CI, 78.5%–89.8%) and 94.9% (95% CI, 88.8%–97.7%), respectively (P < .001). Conclusions The rate of secondary procedures after TEVAR differed between the two cohorts, being substantially lower in the VALOR II trial at 1 year of follow-up. This finding suggests significant benefit from advances in some combination of operator experience, imaging systems, treatment planning, and device design.
    Journal of vascular and interventional radiology: JVIR 01/2014; · 1.81 Impact Factor
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    ABSTRACT: Purpose To compare the durability of TEVAR in two similar clinical trials using early and later generation stent grafts. Materials and Methods Secondary procedures from the prospective, multicenter, clinical trial databases of the test arm of the VALOR and VALOR II trials were analyzed at 3 years. Descriptive and statistical analyses were employed to compare the rate of and potential predictors for the need for secondary procedures. Results A total of 127 and 96 patients were available for a minimum of 3 years of follow-up in the test arm of VALOR and VALOR II, respectively. A total of 25 secondary procedures were performed on 24 patients in the VALOR test arm and 6 patients had 8 secondary procedures in VALOR II. Endoleak was attributable to 21 of 25 secondary procedures (84.0%) in the VALOR test arm and 5 of 8 secondary procedures (62.5%) in VALOR II. A higher rate of endoleak was consistently reported in the test arm of VALOR relative to the VALOR II trial through 3 years of follow-up (P=0.03). By the first year post-index procedure, VALOR II patients were significantly less likely to have undergone a secondary procedure compared to patients in the test arm of VALOR (OR = 0.08, 95% CI: 0.01-0.63, P=0.02). Multivariate predictors at 3 years for the need for a secondary procedure in the VALOR test arm were maximum aneurysm diameter (P=0.002) and aneurysm length (P=0.01). By univariate analysis, proximal neck length was not a predictor for the need for a secondary procedure, but proximal neck diameter was. The estimated freedom from secondary procedures in the VALOR test arm and VALOR II at 3 years was 85.1% (95% CI: 78.5%-89.8%) and 94.9% (95% CI: 88.8%-97.7%), respectively (P<0.001). The estimated survival in the VALOR test arm and VALOR II at 3 years was 71% (95% CI: 63.6%-76.8%) and 94% (95% CI: 85.4%-97.5%) respectively (P<0.001). Conclusion The rate of secondary procedures post-TEVAR differed between the nearly identically designed trials, being substantially less in the VALOR II trial at one year of follow-up. This finding suggests significant benefit from advances in some combination of operator experience, imaging systems, treatment planning and device design.
    Journal of Vascular and Interventional Radiology. 01/2014; 25(3):S9.
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    ABSTRACT: Growing evidence suggests that peak wall stress (PWS) derived from finite element analysis (FEA) of abdominal aortic aneurysms (AAAs) predicts clinical outcomes better than diameter alone. Prior models assume uniform wall thickness (UWT). We hypothesize that the inclusion of locally variable wall thickness (VWT) into FEA of AAAs will improve its ability to predict clinical outcomes. Patients with AAAs (n = 26) undergoing radiologic surveillance were identified. Custom MATLAB algorithms generated UWT and VWT aortic geometries from computed tomography angiography images, which were subsequently loaded with systolic blood pressure using FEA. PWS and aneurysm expansion (as a proxy for rupture risk and the need for repair) were examined. The average radiologic follow-up time was 22.0 ± 13.6 months and the average aneurysm expansion rate was 2.8 ± 1.7 mm/y. PWS in VWT models significantly differed from PWS in UWT models (238 ± 68 vs 212 ± 73 kPa; P = .025). In our sample, initial aortic diameter was not found to be correlated with aneurysm expansion (r = 0.26; P = .19). A stronger correlation was found between aneurysm expansion and PWS derived from VWT models compared with PWS from UWT models (r = 0.86 vs r = 0.58; P = .032 by Fisher r to Z transformation). The inclusion of locally VWT significantly improved the correlation between PWS and aneurysm expansion. Aortic wall thickness should be incorporated into future FEA models to accurately predict clinical outcomes.
    Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 10/2013; · 3.52 Impact Factor
  • B J Herdrich, R M Fairman
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    ABSTRACT: Aortic endografts have become the preferred treatment for aneurysms of the descending thoracic aorta and the infrarenal aorta. The prevalence of endograft infections is about 0.6%, and with the growing number of patients with aortic endografts, the number of patients with endograft infections has also increased. It is important for physicians who treat aneurysmal disease with endografting to understand the pathophysiology, work-up, and treatment options available. Currently, the mainstay of treatment is prolonged antibiotic therapy, explant of all prosthetic material, and reconstruction of the vasculature with either an in situ or extra-anatomic bypass. However, there is a growing experience of less invasive treatment strategies that can be used in patients who cannot withstand an operation of this magnitude.
    The Journal of cardiovascular surgery 10/2013; 54(5):595-604. · 1.51 Impact Factor
  • European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 09/2013; · 2.40 Impact Factor
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    ABSTRACT: Wall stress calculated using finite element analysis has been used to predict rupture risk of aortic aneurysms. Prior models often assume uniform aortic wall thickness and fusiform geometry. We examined the effects of including local wall thickness, intraluminal thrombus, calcifications, and saccular geometry on peak wall stress (PWS) in finite element analysis of descending thoracic aortic aneurysms. Computed tomographic angiography of descending thoracic aortic aneurysms (n=10 total, 5 fusiform and 5 saccular) underwent 3-dimensional reconstruction with custom algorithms. For each aneurysm, an initial model was constructed with uniform wall thickness. Experimental models explored the addition of variable wall thickness, calcifications, and intraluminal thrombus. Each model was loaded with 120 mm Hg pressure, and von Mises PWS was computed. The mean PWS of uniform wall thickness models was 410±111 kPa. The imposition of variable wall thickness increased PWS (481±126 kPa, P<0.001). Although the addition of calcifications was not statistically significant (506±126 kPa, P=0.07), the addition of intraluminal thrombus to variable wall thickness (359±86 kPa, P≤0.001) reduced PWS. A final model incorporating all features also reduced PWS (368±88 kPa, P<0.001). Saccular geometry did not increase diameter-normalized stress in the final model (77±7 versus 67±12 kPa/cm, P=0.22). Incorporation of local wall thickness can significantly increase PWS in finite element analysis models of thoracic aortic aneurysms. Incorporating variable wall thickness, intraluminal thrombus, and calcifications significantly impacts computed PWS of thoracic aneurysms; sophisticated models may, therefore, be more accurate in assessing rupture risk. Saccular aneurysms did not demonstrate a significantly higher normalized PWS than fusiform aneurysms.
    Circulation 09/2013; 128(26 Suppl 1):S157-62. · 15.20 Impact Factor
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    ABSTRACT: To examine outcomes of carotid angioplasty and stenting (CAS) in patients with critical carotid stenosis who are deemed high risk for carotid endarterectomy. Medical records were retrospectively analyzed for patients undergoing CAS between September 2002 and March 2011 at a single institution. Patients were classified as having either critical (≥90%) or high-grade (70%-89%) carotid stenosis based on angiography. The primary composite end point was stroke, myocardial infarction, or death from any cause during the periprocedural period or any ipsilateral stroke during the follow-up period. A total of 245 patients underwent 257 CAS procedures during the study period. Fifty-one percentage (n = 130) of cases involved critical stenosis (66.2% male; mean age, 71 ± 10 y), with the remaining group (n = 127) involving high-grade stenosis (67.7% male; mean age, 71 ± 9 y). Symptomatic carotid disease was present in 25% of the critical stenosis and 31% of the high-grade stenosis groups (P = 0.33). Chronic obstructive pulmonary disease was more commonly found in the high-grade stenosis group (20% versus 8%, P = 0.01). No difference was observed between the groups relative to other baseline demographic characteristics, presence of contralateral carotid occlusion, stent diameter or length, maximum balloon diameter or length, use of embolic protection device, or procedural duration. Technical success was achieved in all cases. There was no difference in the need to predilate before the introduction of the filter or stent based on the degree of stenosis. We found no difference in the primary composite end point between the high-grade or critical stenosis groups (7.1% versus 7.7%, P = 0.74), or there were no differences between the individual components of the composite end point. Mid-term survival was similar between the two groups at a mean follow-up period of 2.4 y. Despite concerns regarding the potential for increased neurologic complications, our data demonstrate that patients with high-grade and critical stenosis are able to safely undergo CAS and achieve similar periprocedural outcomes and mid-term prognosis.
    Journal of Surgical Research 08/2013; · 2.02 Impact Factor
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    ABSTRACT: The management of infected aortic endografts is a challenging endeavor. Treatment of this problem has not been well defined as it is fairly uncommon. However, the incidence is increasing. This study examines the results of treatment at a single center for this morbid process. A retrospective review was performed of patients treated for infected abdominal or thoracic endograft infection following previous abdominal or thoracic endovascular aneurysm repair. Data was reviewed for patient demographics, details of initial endograft implantation, presentation and timeline of subsequent infection, management of infected grafts, and outcomes during follow-up. Overall, 18 patients were treated for infected endografts (thoracic: six, abdominal:12). Three patients were treated between 2000 and 2006, corresponding to a 0.6% institutional incidence of endograft infection (3/473). There were no transfers for infected endografts from outside institutions. From 2006 to 2011, 15 patients underwent treatment. Six were institutional cases of infections (6/945, 0.6% infection rate), however, there was an increase in transfers (n = 9). Median time to presentation with infection from endograft implant was 90 days, with over one-half (61%) presenting within the first 3 months. Tissue and/or blood cultures were positive in 12/16 growing Escherichia coli (n = 1), group A streptococcus (n = 3), methicillin-resistant Staphylococcus aureus (n = 3), or polymicrobial infections (n = 7). The other four patients were culture negative with computed tomography evidence of gas surrounding the endograft and clinical sepsis. Ten patients (abdominal: eight, thoracic: two) were treated with endograft explantation. The remaining eight patients were considered too high-risk for explant or refused open surgery and were therefore managed conservatively without explant (abdominal: four, thoracic: four). At a mean follow-up of 24.7 months, aneurysm-related mortality was 38.9% (n = 7) and was higher for patients presenting with aortoenteric or aortobronchial fistulas (n = 6/10, 60%) (P = .04) and for thoracic stent infections (n = 5/6; 83%) (P = .03). The only survivor of a thoracic infection was managed surgically. Overall survival for patients with abdominal endografts (n = 12) was similar between the eight patients managed surgically (n = 6/8; 75%) and the four selected for medical management (n = 4/4; 100%) (P = .39). All survivors remain on long-term suppressive antibiotics. Two additional patients died of unrelated causes during follow-up. Endograft infection is a rare but increasing complication after abdominal or thoracic endovascular aneurysm repair, which carries significant associated morbidity and mortality. Most endograft infections occurred in proximity to other types of infection, suggesting that bacterial seeding of the endograft was the source. Aortoenteric and aortobronchial fistulas are common presentations, which portend a significantly worse prognosis. Thoracic endograft infections, which have the highest rate of fistulization, have the worst outcomes. Surgical excision continues to be standard of care but conservative management with intravenous antibiotics may be of benefit in certain patients with abdominal endograft infections.
    Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 07/2013; · 3.52 Impact Factor
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    ABSTRACT: Many patients treated with endovascular aortic repair (EVAR) have a concomitant suprarenal abdominal aortic aneurysm (sAAA). The natural history of these sAAAs and whether they require intervention after EVAR is unknown. We identified 470 patients from the M2S database (M2S Inc, West Lebanon, NH) as having an infrarenal AAA (iAAA) with a concomitant sAAA (diameter, 2.9-4.7 cm). The analysis included 217 patients with preoperative computed tomography angiography and follow-up imaging of ≥12 months. Patients who did not undergo EVAR (n = 65) served as a control. Patients with EVAR were subdivided into 90 with suprarenal fixation (SR) and 62 with infrarenal fixation (IR). Standard measurements from the M2S images were extracted, and growth rates were calculated for different abdominal aortic segments. The average follow-up was 33.0 ± 18.8 months. The average sAAA initial size and growth rate were 34.6 ± 3.0 and 0.6 ± 1.1 mm/y for SR, 34.0 ± 3.3 and 0.6 ± 1.3 mm/y for IR, and 36.6 ± 3.4 and 1.2 ± 1.5 mm/y for controls (SR vs IR, P > .05; SR or IR vs control, P < .05). After EVAR, two of 152 (1.3%) sAAAs grew to ≥50 mm, which was not statistically different from four of 65 (6.2%) in the control group (P = .07). At 48 months, the Kaplan-Meier freedom from sAAA growth to ≥50 mm was 99.3% for patients undergoing EVAR and 95.2% for controls (P = .061). Patients with starting sAAAs sized ≥40 mm had a higher growth rate (1.4 ± 2.1 mm/y) and frequency of growth to ≥50 mm (14.3%) than patients with starting sAAAs sized <40 mm (0.7 ± 1.2 mm/y and 1.5%; P < .05). Isolated treatment of iAAAs via EVAR with a concomitant sAAA is acceptable because endografts with or without SR do not affect sAAA growth rates. Routine EVAR follow-up is sufficient for sAAAs of <40 mm, and more intensive follow-up should be considered for sAAAs of 40 to 50 mm. For sAAAs approaching 50 mm, an endograft with IR should be considered in case sAAA repair is required in the future.
    Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 07/2013; · 3.52 Impact Factor
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    ABSTRACT: OBJECTIVE: To explore the incidence, predictors, and outcomes of hemodynamic instability (HI) following carotid angioplasty and stenting (CAS). METHODS: We retrospectively evaluated data on 257 CAS procedures performed in 245 patients from 2002 to 2011 at a single institution. The presence of periprocedural HI, as defined by hypertension (systolic blood pressure >160 mm Hg), hypotension (systolic blood pressure <90 mm Hg), and/or bradycardia (heart rate <60 beats per minute), was recorded. Clinically significant HI (CS-HI) was defined as periprocedural HI lasting greater than 1 hour in total duration. Logistic regression was used to analyze the role of multiple demographic, clinical, and procedural variables. RESULTS: Mean age was 70.9 ± 9.9 years (67% male). HI occurred following 84% (n = 216) of procedures. The incidence of hypertension, hypotension, and bradycardia was 54%, 31%, and 60%, respectively. Sixty-three percent of cases involved CS-HI. Recent stroke was an independent risk factor for the development of CS-HI (odds ratio, 5.24; confidence interval, 1.28-21.51; P = .02), whereas baseline chronic obstructive pulmonary disease was protective against CS-HI (odds ratio, 0.34; confidence interval, 0.15-0.80; P = .01). Patients with CS-HI were more likely to experience periprocedural stroke compared to other patients (8% vs 1%; P = .03). There were no significant differences in the incidence of mortality or other major complications between those with and without CS-HI. CONCLUSIONS: HI represents a common occurrence following CAS. While the presence of periprocedural HI alone did not portend a worse clinical outcome, CS-HI was associated with increased risk of stroke. Expeditious intervention to prevent and manage CS-HI is of critical importance in order to minimize adverse clinical events following CAS.
    Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 05/2013; · 3.52 Impact Factor
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    ABSTRACT: Aneurysms of the extracranial vertebral artery are uncommon, with most cases attributed to penetrating head and neck trauma. We report a 29-year-old man with a symptomatic proximal extracranial vertebral artery aneurysm of unclear etiology. This patient's aneurysm was definitively treated after a successful balloon occlusion test of his affected vertebral artery. An endovascular approach was used combining coil embolization of the distal vertebral artery and a covered stent graft in the subclavian. Although aneurysms of this size and location are traditionally repaired with open aneurysmectomy, we show that endovascular approaches can be a safe and effective alternative.
    Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 04/2013; · 3.52 Impact Factor
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    ABSTRACT: Thoracic endovascular aortic repair has emerged as an effective therapy for a variety of thoracic aortic pathologic entities. However, endograft failure remains a concern, and its treatment is often challenging. We examined our experience with endograft failure and its treatment by endovascular and open repair. From January 2000 to January 2012, 680 patients underwent thoracic endovascular aortic repair at the University of Pennsylvania, and their charts were reviewed for the late outcomes and follow-up data. Of the 680 patients, 73 underwent 80 reinterventions (11.7%) during follow-up. The indications for index thoracic endovascular aortic repair were thoracic aortic aneurysms in 381, type A dissection with frozen elephant trunk in 52, type B dissection in 111, hybrid arch repair in 46, traumatic transection in 37, infection in 10, penetrating atherosclerotic ulcer in 25, and others in 18. The median interval from index thoracic endovascular aortic repair to reintervention was 210 days. Endograft failures included endoleak in 45, proximal aortic events in 11, distal aortic events in 15, endograft infection in 3, and others in 6. Endovascular reintervention (n = 80) was performed in 60 patients. In 20 patients, open aortic reconstructive procedures were performed. The overall 30-day mortality was 8.7% (7/80). During follow-up, 10 late deaths occurred. The overall survival in all patients was 81%, 60%, and 52% at 1, 5, and 7 years, respectively. The late survival for patients after reintervention for endograft failure was similar that for the patients who did not require reintervention (P = .31). Reintervention for endograft failure can be performed with acceptable early outcomes. The mid-term survival for patients requiring reintervention for endograft failure was similar to that of the patients without endograft failure. Thus, reintervention for endograft failure should be aggressively considered when indicated.
    The Journal of thoracic and cardiovascular surgery 03/2013; 145(3 Suppl):S165-70. · 3.41 Impact Factor
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    ABSTRACT: Objective: To examine the results of open or endovascular abdominal aortic aneurysm (AAA) repair following prior open or endovascular thoracic aortic surgery. Methods: A retrospective review of all patients who underwent AAA repair in a delayed fashion following prior thoracic aortic surgery at a single university hospital between 1999 and 2011 was performed. Results: Thirteen patients underwent AAA repair following prior thoracic aortic repair. Mean age was 68.9 ± 6.9 years and 77% (n = 10) were male. Three patients experienced transient delayed-onset spinal cord ischemia (SCI) following initial thoracic surgery. Mean time interval between initial thoracic aortic surgery and subsequent AAA repair was 2.0 ± 1.8 years. Overall rate of SCI and 30-day mortality after delayed AAA repair was 0%. Conclusions: This series does not demonstrate any evidence of increased risk of perioperative mortality or SCI in patients undergoing delayed AAA repair after prior thoracic aortic surgery.
    Vascular and Endovascular Surgery 01/2013; · 0.88 Impact Factor
  • Journal of Vascular Surgery. 01/2013; 57(1):287.
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    ABSTRACT: Endovascular repair of the thoracic aorta has become an increasingly utilized therapy. Although the short-term mortality advantage over open surgery is well documented, late mortality and the impact of presenting pathology on long-term outcomes remain poorly reported. A database was built from 5 prospective studies and a single institutional series. Rates of perioperative adverse events were calculated, as were midterm death and reintervention rates. Multivariate analysis was performed with the use of logistic regression modeling. Kaplan-Meier survival curves were drawn for midterm outcomes. The database contained 1010 patients: 670 patients with thoracic aortic aneurysm, 195 with chronic type B aortic dissection, and 114 with acute type B aortic dissection. Lower elective mortality was observed in patients with chronic dissections (3%) compared with patients with aneurysms (5%). Multivariate analysis identified age, mode of admission, American Society of Anesthesiologists grade, and pathology as independent predictors of 30-day death (P < 0.05). In the midterm, the all-cause mortality rate was 8, 4.9, and 3.2 deaths per 100 patient-years for thoracic aortic aneurysm, acute type B aortic dissection, and chronic type B aortic dissection, respectively. The rates of aortic-related death were 0.6, 1.2, and 0.4 deaths per 100 patient-years for thoracic aortic aneurysm, acute type B aortic dissection, and chronic type B aortic dissection, respectively. This study indicated that the midterm outcomes of endovascular repair of the thoracic aorta are defined by presenting pathology, associated comorbidities, and mode of admission. Nonaortic mortality is high in the midterm for patients with thoracic aortic aneurysm, and managing modifiable risk factors appears vital. Endovascular repair of the thoracic aorta results in excellent midterm protection from aortic-related mortality, regardless of presenting pathology.
    Circulation 01/2013; 127(1):24-32. · 15.20 Impact Factor
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    ABSTRACT: Introduction.—Arterial intima thickness (IMT) of the carotid artery has been established as a surrogate marker of atherosclerosis. The role of femoral IMT remains incompletely defined. This study was undertaken to define the potential relationship between patient demographics, comorbidities, and femoral IMT and to establish it as a potential marker for future peripheral arterial disease.Methods.—A total of 160 patients (89 male, 71 female) between the ages of 18 and 50 years were enrolled and demographic data were obtained by chart review. Images of the common femoral artery were obtained with B-mode ultrasonography gated to the R-wave of the electrocardiograph. Automated edge detection software (Carotid Analyzer for Research) was used to measure femoral IMT and vessel diameter, and these measurements were used to derive the IMT cross-sectional area (CSA). Triplicate measurements of each femoral artery were made and averaged. T-tests and multivariate analysis were performed and significance was indicated by a p Results.—The mean femoral IMT measurements for men and women were 0.514 ± 0.011 mm and 0.465 ± 0.005 mm, respectively. Univariate analysis found significant differences in IMT for sex, age, and presence of diabetes, hypercholesterolemia, and hypertension. Univariate analysis found significant differences in CSA for sex, age, race, body mass index (BMI), and presence of chronic renal insufficiency and hypercholesterolemia. When significant variables were included in a multivariate regression, age and sex (p p Conclusions.—In this subset of patients, multivariate analysis revealed a thicker IMT in males and in patients ≥35 years of age. Greater IMT CSA was associated with male sex, age ≥35 and BMI ≥30. These findings have ramifications for the future study of femoral IMT as it relates to atherosclerosis and vessel remodeling.
    Journal for Vascular Ultrasound. 01/2013; 37(4).
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    ABSTRACT: BACKGROUND: Aortic diseases, including aortic aneurysms, are the 12th leading cause of death in the United States. The incidence of descending thoracic aortic aneurysms is estimated at 10.4 per 100,000 patient-years. Growing evidence suggests that stress measurements derived from structural analysis of aortic geometries predict clinical outcomes better than diameter alone. METHODS: Twenty-five patients undergoing clinical and radiologic surveillance for thoracic aortic aneurysms were retrospectively identified. Custom MATLAB algorithms were employed to extract aortic wall and intraluminal thrombus geometry from computed tomography angiography scans. The resulting reconstructions were loaded with 120 mm Hg of pressure using finite element analysis. Relationships among peak wall stress, aneurysm growth, and clinical outcome were examined. RESULTS: The average patient age was 71.6 ± 10.0 years, and average follow-up time was 17.5 ± 9 months (range, 6 to 43). The mean initial aneurysm diameter was 47.8 ± 8.0 mm, and the final diameter was 52.1 ± 10.0 mm. Mean aneurysm growth rate was 2.9 ± 2.4 mm per year. A stronger correlation (r = 0.894) was found between peak wall stress and aneurysm growth rate than between maximal aortic diameter and growth rate (r = 0.531). Aneurysms undergoing surgical intervention had higher peak wall stresses than aneurysms undergoing continued surveillance (300 ± 75 kPa versus 229 ± 47 kPa, p = 0.01). CONCLUSIONS: Computational peak wall stress in thoracic aortic aneurysms was found to be strongly correlated with aneurysm expansion rate. Aneurysms requiring surgical intervention had significantly higher peak wall stresses. Peak wall stress may better predict clinical outcome than maximal aneurysmal diameter, and therefore may guide clinical decision-making.
    The Annals of thoracic surgery 12/2012; · 3.45 Impact Factor
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    ABSTRACT: BACKGROUND: The efficacy of endovascular treatment of aneurysms secondary to chronic DeBakey type III aortic dissection (CD3) remains controversial. The objective of this study was to compare outcomes from open and endovascular treatment of CD3 aneurysms, and to determine the efficacy of thoracic endovascular aortic repair (TEVAR) in remodeling the chronically dissected thoracoabdominal aorta. METHODS: From 2005 to 2012, 58 patients underwent open aortic replacement (open) and 31 patients underwent endovascular therapy (TEVAR) for the treatment of CD3 aneurysms. The TEVAR patients were divided into CD3a (n = 12) or CD3b (n = 19) subgroups based upon the DeBakey classification of aortic dissection. Total aortic, true and false lumen diameters were measured at different anatomic locations. True lumen and false lumen indices were calculated to evaluate the impact of TEVAR on remodeling. RESULTS: In the open group, operative mortality was 10.3% and the incidence of pulmonary failure, renal failure, and paraplegia was 13.8%, 10.3%, and 12.1%, respectively. There were no operative mortalities in TEVAR patients, and no cases of pulmonary failure, renal failure, or paraplegia. Endovascular therapy stabilized aneurysm size and remodeled the thoracic aorta in 87% of patients. The TEVAR significantly expanded the true lumen and reduced the false lumen within the stent graft in CD3a and CD3b patients (p < 0.001). Thoracic false lumen thrombosis was achieved in 100% of CD3a and in 68% of CD3b patients. CONCLUSIONS: In these early results, TEVAR reduces operative morbidity and mortality compared with open aortic replacement in the treatment of CD3 aneurysms. The TEVAR is effective in remodeling the chronically dissected thoracic aorta. Abdominal false lumen patency is maintained in patients with thoracoabdominal dissection-related aneurysms.
    The Annals of thoracic surgery 12/2012; · 3.45 Impact Factor
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    ABSTRACT: OBJECTIVE: Repair of saccular aortic aneurysms (SAAs) is frequently recommended based on a perceived predisposition to rupture, despite little evidence that these aneurysms have a more malignant natural history than fusiform aortic aneurysms. METHODS: The radiology database at a single university hospital was searched for the computed tomographic (CT) diagnosis of SAA between 2003 and 2011. Patient characteristics and clinical course, including the need for surgical intervention, were recorded. SAA evolution was assessed by follow-up CT, where available. Multivariate analysis was used to examine potential predictors of aneurysm growth rate. RESULTS: Three hundred twenty-two saccular aortic aneurysms were identified in 284 patients. There were 153 (53.7%) men and 131 women with a mean age of 73.5 ± 10.0 years. SAAs were located in the ascending aorta in two (0.6%) cases, the aortic arch in 23 (7.1%), the descending thoracic aorta in 219 (68.1%), and the abdominal aorta in 78 (24.2%). One hundred thirteen (39.8%) patients underwent surgical repair of SAA. Sixty-two patients (54.9%) underwent thoracic endovascular aortic repair, 22 underwent endovascular aneurysm repair (19.5%), and 29 (25.6%) required open surgery. The average maximum diameter of SAA was 5.0 ± 1.6 cm. In repaired aneurysms, the mean diameter was 5.4 ± 1.4 cm; in unrepaired aneurysms, it was 4.4 ± 1.1 cm (P < .001). Eleven patients (3.9%) had ruptured SAAs on initial scan. Of the initial 284 patients, 50 patients (with 54 SAA) had CT follow-up after at least 3 months (23.2 ± 19.0 months). Fifteen patients (30.0%) ultimately underwent surgical intervention. Aneurysm growth rate was 2.8 ± 2.9 mm/yr, and was only weakly related to initial aortic diameter (R(2) = .19 by linear regression, P = .09 by multivariate regression). Decreased calcium burden (P = .03) and increased patient age (P = .05) predicted increased aneurysm growth by multivariate analysis. CONCLUSIONS: While SAA were not found to have a higher growth rate than their fusiform counterparts, both clinical and radiologic follow-up is necessary, as a significant number ultimately require surgical intervention. Further clinical research is necessary to determine the optimal management of SAA.
    Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 11/2012; · 3.52 Impact Factor

Publication Stats

4k Citations
431.48 Total Impact Points

Institutions

  • 2000–2014
    • University of Pennsylvania
      • • Department of Surgery
      • • Division of Vascular Surgery
      • • Department of Medicine
      • • Department of Anesthesiology and Critical Care
      Philadelphia, Pennsylvania, United States
  • 1999–2014
    • Hospital of the University of Pennsylvania
      • • Division of Cardiovascular Surgery
      • • Department of Surgery
      • • Division of Vascular Surgery
      • • Department of Radiology
      Philadelphia, Pennsylvania, United States
  • 2010–2012
    • Emory University
      • Division of Cardiothoracic Surgery
      Atlanta, GA, United States
    • Mayo Clinic - Rochester
      Rochester, Minnesota, United States
  • 2006–2010
    • Massachusetts General Hospital
      • Department of Surgery
      Boston, Massachusetts, United States
    • The University of Chicago Medical Center
      Chicago, Illinois, United States
  • 2009
    • Georgetown University
      Washington, Washington, D.C., United States
    • University of Wisconsin–Madison
      Madison, Wisconsin, United States
  • 2007–2008
    • Columbia University
      New York City, New York, United States
    • University of Pittsburgh
      • Division of Vascular Surgery
      Pittsburgh, PA, United States
  • 2003–2008
    • Harvard Medical School
      • Department of Surgery
      Boston, MA, United States
    • Partners HealthCare
      • Department of Radiology
      Boston, MA, United States
  • 2004
    • Thomas Jefferson University Hospitals
      • Division of Vascular and Endovascular Surgery
      Philadelphia, PA, United States
  • 2001–2004
    • University of Maryland Medical Center
      • Division of Vascular Surgery
      Baltimore, Maryland, United States
  • 2002
    • Wistar Institute
      • Melanoma Research Center
      Philadelphia, Pennsylvania, United States
    • Treatment Research Institute, Philadelphia PA
      Philadelphia, Pennsylvania, United States
    • Anne Arundel Medical Center
      Annapolis, Maryland, United States
  • 2000–2001
    • Union Memorial Hospital
      Baltimore, Maryland, United States