Gonadal Vein Transposition in Nutcracker Syndrome.

BACKGROUND: Nutcracker syndrome, caused by mesoaortic compression of the left renal vein leading to symptoms related to venous hypertension, is an uncommon entity that may require operative intervention. Traditional open transposition of the left renal vein to the vena cava has been shown to have a reintervention rate of up to 30%, while also having additional morbidity associated with laparotomy. More recently, endovascular stenting has been described in several small series but have reported stent fracture, thrombosis, and migration. METHODS: We report the case of a 26-year-old woman with 4 months of intermittent flank pain and hematuria, diagnosed with nutcracker syndrome by both duplex ultrasound and axial based imaging. RESULTS: The patient underwent catheter venography confirming left renal vein compression, which also demonstrated a dilated gonadal vein measuring 11 mm leading to significant pelvic varices. Through a left lower quadrant retroperitoneal exposure, the gonadal vein was transposed to the left common iliac vein with completion venography demonstrating relief of renal venous congestion. The patient was discharged uneventfully with immediate resolution of symptoms and remains symptom-free at 6-month follow-up. CONCLUSIONS: Gonadal vein transposition is an effective alternative surgical treatment for nutcracker syndrome.

Use of computational fluid dynamics studies in predicting aneurysmal degeneration of acute type B aortic dissections.

OBJECTIVE: Whereas uncomplicated acute type B aortic dissections are often medically managed with good outcomes, a subset develop subacute or chronic aneurysmal dilation. We hypothesized that computational fluid dynamics (CFD) simulations may be useful in identifying patients at risk for this complication. METHODS: Patients with acute type B dissection complicated by rapidly expanding aortic aneurysms (N = 7) were compared with patients with stable aortic diameters (N = 7). Three-dimensional patient-specific dissection geometries were generated from computed tomography angiography and used in CFD simulations of pulsatile blood flow. Hemodynamic parameters including false lumen flow and wall shear stress were compared. RESULTS: Patients with rapid aneurysmal degeneration had a growth rate of 5.3 ± 2.7 mm/mo compared with those with stable aortic diameters, who had rates of 0.2 ± 0.02 mm/mo. Groups did not differ in initial aortic diameter (36.1 ± 2.9 vs 34.4 ± 3.6 mm; P = .122) or false lumen size (22.6 ± 2.9 vs 20.2 ± 4.5 mm; P = .224). In patients with rapidly expanding aneurysms, a greater percentage of total flow passed through the false lumen (78.3% ± 9.3% vs 56.3% ± 11.8%; P = .016). The time-averaged wall shear stress on the aortic wall was also significantly higher (12.6 ± 3.7 vs 7.4 ± 2.8 Pa; P = .028). CONCLUSIONS: Hemodynamic parameters derived from CFD simulations of acute type B aortic dissections were significantly different in dissections complicated by aneurysm formation. Thus, CFD may assist in predicting which patients may benefit from early stent grafting.

Local wall thickness in finite element models improves prediction of abdominal aortic aneurysm growth.

OBJECTIVE: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

Validation of semiautomated and locally resolved aortic wall thickness measurements from computed tomography.

OBJECTIVE: Aortic wall thickness (AWT) is important for anatomic description and biomechanical modeling of aneurysmal disease. However, no validated, noninvasive method for measuring AWT exists. We hypothesized that semiautomated image segmentation algorithms applied to computed tomography angiography (CTA) can accurately measure AWT. METHODS: Aortic samples from 10 patients undergoing open thoracoabdominal aneurysm repair were taken from sites of the proximal or distal anastomosis, or both, yielding 13 samples. Aortic specimens were fixed in formalin, embedded in paraffin, and sectioned. After staining with hematoxylin and eosin and Masson's trichrome, sections were digitally scanned and measured. Patients' preoperative CTA Digital Imaging and Communications in Medicine (DICOM; National Electrical Manufacturers Association, Rosslyn, Va) images were segmented into luminal, inner arterial, and outer arterial surfaces with custom algorithms using active contours, isoline contour detection, and texture analysis. AWT values derived from image data were compared with measurements of corresponding pathologic specimens. RESULTS: AWT determined by CTA averaged 2.33 ± 0.66 mm (range, 1.52-3.55 mm), and the AWT of pathologic specimens averaged 2.36 ± 0.75 mm (range, 1.51-4.16 mm). The percentage difference between pathologic specimens and CTA-determined AWT was 9.5% ± 4.1% (range, 1.8%-16.7%). The correlation between image-based measurements and pathologic measurements was high (R = 0.935). The 95% limits of agreement computed by Bland-Altman analysis fell within the range of -0.42 and 0.42 mm. CONCLUSIONS: Semiautomated analysis of CTA images can be used to accurately measure regional and patient-specific AWT, as validated using pathologic ex vivo human aortic specimens. Descriptions and reconstructions of aortic aneurysms that incorporate locally resolved wall thickness are feasible and may improve future attempts at biomechanical analyses.

Omission of adjuvant therapy after gastric cancer resection: development of a validated risk model.

NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Gastric Cancer recommend adjuvant chemotherapy with or without radiotherapy following after resection of gastric adenocarcinoma (GA) for patients who have not received neoadjuvant therapy. Despite frequent noncompliance with NCCN Guidelines nationally, risk factors underlying adjuvant therapy omission (ATom) have not been well characterized. We developed an internally validated preoperative instrument stratifying patients by incremental risk of ATom. The National Cancer Data Base was queried for patients with stage IB-III GA undergoing gastrectomy; those receiving neoadjuvant therapy were excluded. Multivariable models identified factors associated with ATom between 2006 and 2011. Internal validation was performed using bootstrap analysis; model discrimination and calibration were assessed using k-fold cross-validation and Hosmer-Lemeshow procedures, respectively. Using weighted ß-coefficients, a simplified Omission Risk Score (ORS) was created to stratify ATom risk. The impact of ATom on overall survival (OS) was examined in ORS risk-stratified cohorts. In 4,728 patients (median age, 70 years; 64.8% male), 53.7% had ATom. The bootstrap-validated model identified advancing age, comorbidity, underinsured/uninsured status, proximal tumor location, and clinical T1/2 and N0 tumors as independent ATom predictors, demonstrating good discrimination. The simplified ORS, stratifying patients into low-, moderate-, and high-risk categories, predicted incremental risk of ATom (30% vs 53% vs 80%, respectively) and progressive delay to adjuvant therapy initiation (median time, 51 vs 55 vs 61 days, respectively). Patients at moderate/high-risk of ATom demonstrated worsening risk-adjusted mortality compared with low-risk patients (median OS, 26.4 vs 29.2 months). This ORS may aid in rational selection of multimodality treatment sequence in GA.

Impact of wall thickness and saccular geometry on the computational wall stress of descending thoracic aortic aneurysms.

BACKGROUND: 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. METHODS AND RESULTS: 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). CONCLUSIONS: 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.

Complications following reduction mammaplasty: a review of 3538 cases from the 2005-2010 NSQIP data sets.

BACKGROUND: Reduction mammaplasty is an established and effective technique to treat symptomatic macromastia. Variable rates of complications have been reported, and there is a continued need for better outcome assessment studies. OBJECTIVE: The authors investigate predictors of postoperative complications following reduction mammaplasty using the National Surgery Quality Improvement Program (NSQIP) data sets. METHODS: The 2005-2010 American College of Surgeons NSQIP databases were reviewed to identify primary encounters for reduction mammaplasty using Current Procedural Terminology code 19318. Two complication types were recorded: major complications (deep infection and return to operating room) and any complication (all surgical complications). Preoperative patient factors and comorbidities, as well as intraoperative variables, were assessed. A multivariate regression analysis was used to identify independent predictors of complications. RESULTS: A total of 3538 patients were identified with an average age of 43 years and body mass index of 31.6 kg/m(2). Most patients underwent outpatient surgery (80.5%) with an average operative time of 180 minutes. The incidence of overall surgical complications was 5.1%. The following factors were independently associated with any surgical complications: morbid obesity (odds ratio [OR], 2.1; P < .001), active smoking (OR, 1.7; P < .001), history of dyspnea (OR, 2.0; P < .001), and resident participation (OR, 1.8; P = .01). The incidence of major surgical complications was 2.1%. Factors associated with major complications included active smoking (OR, 2.7; P < .001), dyspnea (OR, 2.6; P < .001), resident participation (OR, 2.1; P < .001), and inpatient surgery (OR, 1.8; P = .01). CONCLUSIONS: This study demonstrates overall incidence of complications in 1 in 20 patients and a 1 in 50 incidence of a major surgical complication. Noteworthy findings include the identification of morbid obesity as a significant predictor of overall morbidity and active smoking as a strong predictor of major surgical morbidity. These data can assist surgeons in preoperative counseling and enhance perioperative decision making.

Patterns of preoperative laboratory testing in patients undergoing outpatient plastic surgery procedures.

BACKGROUND: Preoperative laboratory testing is commonplace in the clinical setting and is often utilized at surgeon discretion. We searched the American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP) data set to determine the impact of preoperative laboratory testing in ambulatory plastic surgery patients. OBJECTIVE: The authors assess the utilization and predictive value of preoperative laboratory testing in outpatient plastic surgery procedures. METHODS: Patients undergoing ambulatory plastic surgery were identified from the 2005 to 2010 NSQIP databases. Laboratory tests were categorized by group: hematologic, chemistry, coagulation, and liver function tests (LFT). We defined complications in 2 groups: major postoperative and wound complications. Multivariate analyses were used to identify patient characteristics associated with testing and to assess the ability of laboratory testing to predict postoperative complications. RESULTS: A total of 5359 (62.0%) patients underwent testing; 881 (16.4%) tests were performed on the day of surgery. In patients with no defined NSQIP comorbidities, 59.4% underwent preoperative testing and had a significantly lower rate of abnormal findings (33.4% vs 25.3%, P < .0001). In multivariate analyses, testing was associated with older age, American Society of Anesthesiologists class >2, Hispanic or African American race, body contouring procedures, epidural or spinal procedures, and with diabetes, hypertension, and cancer. Major complications occurred in 0.34% of patients. Our analysis demonstrated that neither testing nor abnormal results were associated with postoperative complications, either major (P = .178) or wound (P = .150). CONCLUSIONS: We found no association between abnormal laboratory testing and postoperative morbidity. Preoperative testing in low-risk ambulatory plastic surgery patients may be costly and has limited direct clinical benefit.

Three-dimensional echocardiographic analysis of mitral annular dynamics: implication for annuloplasty selection.

BACKGROUND: Proponents of flexible annuloplasty rings have hypothesized that such devices maintain annular dynamics. This hypothesis is based on the supposition that annular motion is relatively normal in patients undergoing mitral valve repair. We hypothesized that mitral annular dynamics are impaired in ischemic mitral regurgitation and myxomatous mitral regurgitation. METHODS AND RESULTS: A Philips iE33 echocardiographic module and X7-2t probe were used to acquire full-volume real-time 3-dimensional transesophageal echocardiography loops in 11 normal subjects, 11 patients with ischemic mitral regurgitation and 11 patients with myxomatous mitral regurgitation. Image analysis was performed using Tomtec Image Arena, 4D-MV Assessment, 2.1 (Munich, Germany). A midsystolic frame was selected for the initiation of annular tracking using the semiautomated program. Continuous parameters were normalized in time to provide for uniform systolic and diastolic periods. Both ischemic mitral regurgitation (9.98 ± 155 cm(2)) and myxomatous mitral regurgitation annuli (13.29 ± 3.05 cm(2)) were larger in area than normal annuli (7.95 ± 1.40 cm(2)) at midsystole. In general, ischemic mitral regurgitation annuli were less dynamic than controls. In myxomatous mitral regurgitation, annular dynamics were also markedly abnormal with the mitral annulus dilating rapidly in early systole in response to rising ventricular pressure. CONCLUSIONS: In both ischemic mitral regurgitation and myxomatous mitral regurgitation, annular dynamics and anatomy are abnormal. Flexible annuloplasty devices used in mitral valve repair are, therefore, unlikely to result in either normal annular dynamics or normal anatomy.

Endovascular treatment of a symptomatic extracranial vertebral artery aneurysm.

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.

Incidence, predictors, and outcomes of hemodynamic instability following carotid angioplasty and stenting.

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.

A modern experience with saccular aortic aneurysms.

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 (R2=.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.

Results of carotid angioplasty and stenting are equivalent for critical versus high-grade lesions in patients deemed high risk for carotid endarterectomy.

BACKGROUND: To examine outcomes of carotid angioplasty and stenting (CAS) in patients with critical carotid stenosis who are deemed high risk for carotid endarterectomy. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Preoperative Three-Dimensional Valve Analysis Predicts Recurrent Ischemic Mitral Regurgitation After Mitral Annuloplasty.

BACKGROUND: Valve repair for ischemic mitral regurgitation (IMR) with undersized annuloplasty rings is characterized by high IMR recurrence rates. Patient-specific preoperative imaging-based risk stratification for recurrent IMR would optimize results. We sought to determine if prerepair three-dimensional (3D) echocardiography combined with a novel valve-modeling algorithm would be predictive of IMR recurrence 6 months after repair. METHODS: Intraoperative transesophageal real-time 3D echocardiography was performed in 50 patients undergoing undersized ring annuloplasty for IMR and in 21 patients with normal mitral valves. A customized image analysis protocol was used to assess 3D annular geometry and regional leaflet tethering. IMR recurrence (≥ grade 2) was assessed with two-dimensional transthoracic echocardiography 6 months after repair. RESULTS: Preoperative annular geometry was similar in all IMR patients, and preoperative leaflet tethering was significantly higher in patients with recurrent IMR (n=13) than in patients in whom IMR did not recur (n=37) (tethering index: 3.91 ± 1.01 vs 2.90 ± 1.17, p = 0.008; tethering angles of A3: 23.5° ± 8.9° vs 14.4° ± 11.4°, p = 0.012; P2: 44.4° ± 8.8° vs 28.2° ± 17.0°, p = 0.002; and P3: 35.2° ± 6.0° vs. 18.6° ± 12.7°, p < 0.001). Multivariate logistic regression analysis revealed the preoperative P3 tethering angle as an independent predictor of IMR recurrence with an optimal cutoff value of 29.9° (area under the curve, 0.92; 95% confidence interval, 0.84 to 1.00; p < 0.001). CONCLUSIONS: 3D echocardiography combined with valve modeling is predictive of recurrent IMR. Preoperative regional leaflet tethering of segment P3 is a strong independent predictor of IMR recurrence after undersized ring annuloplasty. In patients with a preoperative P3 tethering angle of 29.9° or larger, chordal-sparing valve replacement rather than valve repair should be strongly considered.

The value of preoperative 3-dimensional over 2-dimensional valve analysis in predicting recurrent ischemic mitral regurgitation after mitral annuloplasty.

OBJECTIVES: Repair for ischemic mitral regurgitation with undersized annuloplasty is characterized by high recurrence rates. We sought to determine the value of pre-repair 3-dimensional echocardiography over 2-dimensional echocardiography in predicting recurrence at 6 months. METHODS: Intraoperative transesophageal 2-dimensional echocardiography and 3-dimensional echocardiography were performed in 50 patients undergoing undersized annuloplasty for ischemic mitral regurgitation. Two-dimensional echocardiography annular diameter and tethering parameters were measured in the apical 2- and 4-chamber views. A customized protocol was used to assess 3-dimensional annular geometry and regional leaflet tethering. Recurrence (grade ≥2) was assessed with 2-dimensional transthoracic echocardiography at 6 months. RESULTS: Preoperative 2- and 3-dimensional annular geometry were similar in all patients with ischemic mitral regurgitation. Preoperative 2- and 3-dimensional leaflet tethering were significantly higher in patients with recurrence (n = 13) when compared with patients without recurrence (n = 37). Multivariate logistic regression revealed preoperative 2-dimensional echocardiography posterior tethering angle as an independent predictor of recurrence with an optimal cutoff value of 32.0° (area under the curve, 0.81; 95% confidence interval, 0.68-0.95; P = .002) and preoperative 3-dimensional echocardiography P3 tethering angle as an independent predictor of recurrence with an optimal cutoff value of 29.9° (area under the curve, 0.92; 95% confidence interval, 0.84-1.00; P < .001). The predictive value of the 3-dimensional geometric multivariate model can be augmented by adding basal aneurysm/dyskinesis (area under the curve, 0.94; 95% confidence interval, 0.87-1.00; P < .001). CONCLUSIONS: Preoperative 3-dimensional echocardiography P3 tethering angle is a stronger predictor of ischemic mitral regurgitation recurrence after annuloplasty than preoperative 2-dimensional echocardiography posterior tethering angle, which is highly influenced by viewing plane. In patients with a preoperative P3 tethering angle of 29.9° or larger (especially when combined with basal aneurysm/dyskinesis), chordal-sparing valve replacement should be strongly considered.

Predicting the need for muscle flap salvage after open groin vascular procedures: a clinical assessment tool.

Groin wound complications after open vascular surgery procedures are common, morbid, and costly. The purpose of this study was to generate a simple, validated, clinically usable risk assessment tool for predicting groin wound morbidity after infra-inguinal vascular surgery. A retrospective review of consecutive patients undergoing groin cutdowns for femoral access between 2005-2011 was performed. Patients necessitating salvage flaps were compared to those who did not, and a stepwise logistic regression was performed and validated using a bootstrap technique. Utilising this analysis, a simplified risk score was developed to predict the risk of developing a wound which would necessitate salvage. A total of 925 patients were included in the study. The salvage flap rate was 11.2% (n = 104). Predictors determined by logistic regression included prior groin surgery (OR = 4.0, p < 0.001), prosthetic graft (OR = 2.7, p < 0.001), coronary artery disease (OR = 1.8, p = 0.019), peripheral arterial disease (OR = 5.0, p < 0.001), and obesity (OR = 1.7, p = 0.039). Based upon the respective logistic coefficients, a simplified scoring system was developed to enable the preoperative risk stratification regarding the likelihood of a significant complication which would require a salvage muscle flap. The c-statistic for the regression demonstrated excellent discrimination at 0.89. This study presents a simple, internally validated risk assessment tool that accurately predicts wound morbidity requiring flap salvage in open groin vascular surgery patients. The preoperatively high-risk patient can be identified and selectively targeted as a candidate for a prophylactic muscle flap.

Validated model for predicting postoperative respiratory failure: analysis of 1706 abdominal wall reconstructions.

BACKGROUND: Abdominal wall reconstruction can be associated with significant rates of respiratory events. In this current study, the authors aim to characterize perioperative risk factors associated with postoperative respiratory failure and derive a model with which to predict postoperative respiratory failure. METHODS: The authors reviewed the 2005 to 2010 American College of Surgeons National Surgical Quality Improvement Program databases, identifying encounters for Current Procedural Terminology codes for both hernia repair (49560, 49561, 49565, 49566, and 49568) and component separation (15734). A predictive model of postoperative respiratory failure was developed using logistic regression analyses and validated using a bootstrap technique. RESULTS: Of 1706 patients undergoing complex abdominal reconstructions in the study period, 102 (6.0 percent) experienced postoperative respiratory failure. Patients experiencing postoperative respiratory failure had longer admissions (21.0±18.5 versus 5.9±5.5 days, p<0.001) and a higher mortality rate (14.7 percent versus 0.1 percent, p<0.001). Multivariate logistic regression revealed eight variables significantly associated with postoperative respiratory failure. A history of chronic obstructive pulmonary disease (p<0.001), dyspnea at rest (p=0.032), dependent functional status (p=0.032), malnutrition (p<0.001), recurrent incarcerated hernia (p=0.006), concurrent intraabdominal procedure (p=0.041), American Society of Anesthesiologists score greater than 3 (p<0.001), and prolonged operative time (p<0.001) were independently associated with higher rates of postoperative respiratory failure. The multivariate model was internally validated using a bootstrap technique and had good discrimination (c statistic=0.78). CONCLUSIONS: A validated predictive model and clinical risk-assessment tool of postoperative respiratory failure following abdominal wall reconstruction is presented. Respiratory complications were associated with significantly longer hospital stays and higher rates of mortality. Data derived from this large cohort can be used to risk-stratify patients and to enhance perioperative decision-making. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Peak wall stress predicts expansion rate in descending thoracic aortic aneurysms.

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.

Delayed complications of inferior vena cava filters: case report and literature review.

Inferior vena cava (IVC) filters are frequently placed to prevent pulmonary embolism in patients in whom anticoagulation is contraindicated or ineffective. Delayed erosion of the filter into adjacent vital structures is a rare complication. We report 3 complications of IVC filters managed with both surgical and endovascular therapies. A review of the available literature addresses incidence of delayed IVC filter complications, the approach to these problems, and the role of retrievable IVC filters.