Carotid artery stenting: analysis of data for 105 patients at high risk

OBJECTIVES: Carotid artery stenting (CAS) has been recommended as an alternative to carotid endarterectomy (CEA) by some clinicians. However, recently published clinical trials have reported 30-day stroke and death rates of 10% to 12%. This prompted review of our experience with CAS in patients at high risk, to document our results and guide further use of CAS. METHODS: From September 1996 to the present, we performed 114 consecutive CAS procedures in 105 patients. Sixty-three patients were men (60%) and 42 patients were women (40%), with mean age of 70 years (range, 45-93 years). Indications for CAS included recurrent stenosis after previous CEA in 74 patients (65%), primary lesions in 32 patients at high risk (28%), and carotid stenosis with previous ipsilateral radiation therapy in 8 patients (7%). Asymptomatic stenosis (>80%) was managed in 70 patients (61%), and symptomatic lesions (>50%) were treated in 44 patients (39%). RESULTS: CAS was technically successful in all patients. Mean severity of stenosis before CAS was 87% +/- 6%, compared with 9% +/- 4% after CAS. Two patients (1.9%) died, 1 of reperfusion-intracerebral hemorrhage and 1 of myocardial infarction 10 days after discharge; and 1 patient (0.95%) had a stroke (retinal infarction), for a 30-day stroke and death rate of 2.85%. Two patients (1.9%) had transient neurologic events. No cranial nerve deficits were noted. No neurologic complications have been noted in the last 27 patients (26%). CONCLUSIONS: A 30-day stroke and death rate of 2.85% in our experience demonstrates acceptability of CAS as an alternative to repeat operation or primary CEA in patients at high risk or in patients with radiation-induced stenosis. We recommend further clinical investigation of CAS and participation in clinical trials by vascular surgeons.     

Carotid artery stenting: is there a need to revise ultrasound velocity criteria?

OBJECTIVES: Ultrasound (US) velocity criteria have not been well-established for patients undergoing carotid artery stenting (CAS). A potential source of error in using US after CAS is that reduced compliance in the stented artery may result in elevated velocity relative to the native artery. We measured arterial compliance in the stented artery, and developed customized velocity criteria for use early after CAS. METHODS: US was performed before and within 3 days after CAS, and after 1 month in a subset of 26 patients. Post-procedural peak systolic velocity (PSV) and end-diastolic velocity (EDV) of the internal carotid artery (ICA), PSV/EDV ratio, and internal carotid artery to common carotid artery ratio (ICA/CCA) were recorded. These were compared with degree of in-stent residual stenosis determined at carotid angiography performed at the completion of CAS. Peterson's elastic modulus (Ep) and compliance (Cp) of the ICA were determined in a subgroup of 20 patients at the distal end of the stent and in the same region in the native ICA before stenting. RESULTS: Ninety CAS procedures were analyzed. Mean (+/-SD) angiographic residual stenosis after CAS was 5.4 +/- 9.1%, whereas corresponding PSV by US was 120.4 +/- 32.4 cm/s; EDV, 41.4 +/- 18.6 cm/s; PSV/EDV ratio, 3.3 +/- 1.2; and ICA/CCA ratio, 1.6 +/- 0.5. PSV was unchanged at 1 month. Post-CAS PSV and ICA/CCA ratio correlated most with degree of stenosis (P <.0001 for both). Only six patients demonstrated in-stent residual stenosis 20% or greater, but the standard US threshold of PSV 130 cm/s or greater (validated for >20% ICA stenosis in our laboratory) categorized 38 of 90 patients as having stenosis 20% or greater. Receiver operator curve analysis demonstrated that a combined threshold of PSV 150 cm/s or greater and ICA/CCA ratio 2.16 or greater were optimal for detecting residual stenosis of 20% or greater, with sensitivity 100%, specificity 98%, positive predictive value 75%, and negative predictive value 100%. After placement of a stent, the ICA demonstrated significantly increased Ep (1.2 vs 4.4 x 10(3) mm Hg; P =.004) and decreased Cp (9.8 vs 3.2 %mm Hg x 10(-2); P =.0004). CONCLUSIONS: Currently accepted US velocity criteria validated in our laboratory for nonstented ICAs falsely classified several stented ICAs with normal diameter on carotid angiograms as having residual in-stent stenosis 20% or greater. We propose a new criterion that defines PSV less than 150 cm/s, with ICA/CCA ratio less than 2.16, as the best correlate to a normal lumen (0%-19% stenosis) in the recently stented ICA. This was associated with increased stiffness of the stented ICA (increased Ep, decreased Cp). These preliminary results suggest that placement of a stent in the carotid artery alters its biomechanical properties, which may cause an increase in US velocity measurements in the absence of a technical error or residual stenotic disease.     

Influence of HLA disparity,immunosuppressive regimen used,and type of kidney allograft on production of anti-HLA class-I antibodies after transplant and occurrence of rejection

We studied the effects of HLA disparity, immunosuppressive regimen used, and the type of kidney allograft on production of anti-HLA antibodies after transplant and the occurrence of rejection episodes.

Five living-unrelated donors and 4 living-related donors kidney recipients received quadruple therapy (including sirolimus and mycophenolate mofetil). Fifteen living-unrelated donors and 19 living-related donors received triple therapy (excluding sirolimus). A single bolus of 4 to 6 mg/kg rabbit anti-human T-lymphocyte immune serum was included with both regimens. Recipients were studied over a 3-year period. Human leukocyte antigen profiles were determined by DNA (SSP) typing, and anti-HLA class-I antibodies were determined by the complement-dependent microcytotoxicity assay and an enzyme-linked immunosorbent assay.

The degree of HLA disparity did not appear to affect anti-HLA antibody production or the occurrences of rejection episodes. None of the patients who received quadruple therapy developed anti-HLA class-I antibodies. Two living-unrelated donors and 2 living-related donors recipients who received triple therapy developed anti-HLA class-I antibodies. One of the 2 living-unrelated donors antibody-positive patients rejected the kidney and returned to dialysis, and the other patient has normal graft function 3 years after the transplant. The 2 living-related donors patients with normal graft function were antibody-positive 1 year after the transplant but were antibody-negative at 2 and 3 years after transplant.

Sirolimus appeared to inhibit production of antibodies after transplant. Moreover, use of present day immunosuppressive agents diminishes the role of HLA matching in relation to the occurrence of rejection episodes.     

Results of Laparoscopic Sleeve Gastrectomy in 541 Consecutive Patients with Low Baseline Body Mass Index (30–35 kg/m<Superscript>2</Superscript>)

Background

Laparoscopic sleeve gastrectomy (LSG) is currently the leading bariatric procedure and targets, among other obesity classes, patients with BMI 30–35 kg/m², which are reaching alarming proportions.

Methods

Between February 2010 and August 2015, data on 541 consecutive patients with BMI 30–35 kg/m² undergoing LSG were prospectively collected and analyzed.

Results

Mean age was 32?±?8 years (13–65) and 419 (77.4 %) were women. Preoperative weight was 92.0?±?8.8 kg (65–121) and BMI was 32.6?±?1.5 kg/m² (30–35). Comorbidities were detected in 210 (39 %) patients. Operative time was 74?±?12 min (40–110) and postoperative stay was 1.7?±?0.22 days (1–3). There were no deaths, leaks, abscesses or strictures and the rate of hemorrhage was 1.2 %. At 1 year, 98 % were followed and BMI decreased to 24.7?±?1.6, the percentage of total weight loss (% TWL) was 24.1?±?4.7 while the percentage of excess BMI loss (%EBMIL) reached 106.1?±?24.1. At 5 years, 76 % of followed patients achieved a ≥50 % EBMIL.

Conclusion

With appropriate surgical expertise, LSG in patients with BMI 30–35 kg/m² achieved excellent outcomes with a zero fistula rate.

     

Endoscopic Stenting of Gastric Staple Line Leak Following Sleeve Gastrectomy

Laparoscopic sleeve gastrectomy is known to be associated with a risk of gastric staple line leak. We report on our experience with endoscopic stenting of the anomalous leaking tract. Three cases of post sleeve gastric leak confirmed by computed tomography scan were treated by endoscopic stenting of their leak with a plastic endoprosthesis under fluoroscopic and endoscopic guidance. Endoscopic stenting by means of biliary or pancreatic endoprosthesis was successful in the three patients. The median number of endoscopy procedures per patient was 1.3. Stents were extracted 6 to 10 weeks after their placement. Neither morbidity nor recurrence was noticed on follow-up. Endoscopic stenting of gastric staple line leak following sleeve gastrectomy proved to be an efficacious technique for leak healing.     

Systematic review of major osteoporotic fracture to hip fracture incidence rate ratios worldwide: implications for Fracture Risk Assessment Tool (FRAX)-derived estimates

The Fracture Risk Assessment Tool (FRAX) is the most widely used tool for fracture prediction. It provides 10-year probabilities for hip and major osteoporotic fracture (MOF). It uses country-specific hip fracture incidence and life expectancy data, and for most countries, MOF/hip fracture incidence rate ratios (IRRs) from Malmo Sweden. However, the risk of MOF varies by age, sex, and geography. The objective is to compare the MOF/hip IRRs across countries, by sex and age. This systematic review targeted observational studies of MOF and hip fractures in individuals >50 years (PROSPERO 2019 CRD42019129259). One reviewer screened potential articles. Two reviewers completed duplicate and independent data abstraction, and assessed study quality based on population representativeness, study design and duration, definition of ethnicity, and fracture characteristics. We calculated the MOF/hip IRRs (95% confidence interval) and Z-values to compare IRRs in various countries to those for Sweden. We included 27 studies, of fair to good quality in the majority, from Europe (15), US and Canada (7), Asia (3), and Australia (2). The IRRs were twofold to 10-fold higher in younger compared to older age categories, and in women compared to men, with few exceptions. Within Europe, and using Sweden as a reference, MOF/Hip IRRs in women 50–54 years from Finland, Italy, Netherlands, Denmark, and UK were significantly lower by 38% to 60%. Findings were similar in men. At older ages, MOF/Hip IRRs were consistently lower in women from European countries compared to Sweden, by 10%–40% and 11%–51%, at 75–79 years and 85–89 years, respectively. Findings were heterogenous in men and in non-European countries. In conclusion, the MOF/hip fracture IRR may vary between countries. The variability at older ages may affect FRAX prediction when country-specific fracture IRRs are not used. Further research is needed to elucidate the implication of our findings to FRAX-derived MOF estimates in various countries. © 2021 American Society for Bone and Mineral Research (ASBMR).     

Technical challenges in a program of carotid artery stenting

OBJECTIVES: Successful carotid artery stenting (CAS) involves gaining access to the common carotid artery, characterizing and crossing the lesion, deploying an anti-embolic device and stent, and retrieving the anti-embolic device. These steps are critical determinants of the complexity of the procedure. The frequency with which technical challenges are encountered during CAS is ill-defined. The purpose of this investigation was to review the incidence and types of technical challenges encountered during CAS and determine their effect on outcome. METHODS: Data were prospectively collected for 194 consecutive CAS procedures (177 patients) and separated into group 1, standard CAS technique, and group 2, procedures with technical challenges requiring modifications to the technique. Technical challenges were defined as difficult femoral arterial access (aortoiliac occlusive disease), complex aortic arch anatomy (elongated or bovine arch, deep takeoff of the innominate artery, tandem stenoses (CCA, innominate artery), difficult internal carotid artery anatomy (tortuosity, high-grade stenosis), and circumferential internal carotid artery calcification. The incidence of technical challenges, types of technical modifications required, and effect on outcomes were determined. RESULTS: Fifty technically challenging situations (26%) were encountered in 194 CAS procedures (group 2), which required advanced technical skills. Standard methods were used in the other 144 procedures (group 1, 74%). No significant differences in 30-day stroke and death rates were noted between the groups (group 1, 3.1%; group 2, 2.0%; P = .564). CONCLUSIONS: Twenty-six percent of the procedures required a modification in the standard technique for successful CAS. Circumferential calcification and severe tortuosity continue to be relative contraindications to CAS. Recognition of these technical challenges and increasing facility with the methods to manage them will enable expanded use of CAS without increased morbidity and mortality.     

Risk factors for conversion to laparotomy during laparoscopic management of an ectopic pregnancy

Objective: To identify risk factors for conversion to laparotomy during laparoscopic management of ectopic pregnancy. Methods: A retrospective chart review of patients who underwent laparoscopy for treatment of ectopic pregnancy, during a 32-month period (6/1999–2/2002), at the University of Miami Jackson Memorial Hospital. We identified 229 patients; 201 had a successful laparoscopy (non-converted group) and 28 who were converted to laparotomy (converted group).Variables analyzed between the two groups were demographic data, patient-related risk factors available to the surgeon prior to the surgery (previous laparotomy, previous laparoscopy, history of PID, history of endometriosis, diameter of ectopic pregnancy as measured by ultrasound, amount of free fluid on ultrasound, BMI), and surgeons’ experience. Results: Out of the 229 laparoscopies, 28 were converted to laparotomy (12.2%). The rate of conversion was significantly higher for less experienced compared to experienced surgeon (OR=6.1, 95% CI=2.35–15.88). Significantly more women had a BMI>30 kg/m² in the converted group compared to the non-converted group (42% vs. 14%; OR=4.28, 95% CI=1.7–10.75) and the converted group had significantly higher rate of large free fluid reported on ultrasound compared to the non-converted group (21.42% vs. 7.46%; OR =3.38, 95% CI=1.04–10.61). Conclusion: Less experienced surgeon, BMI>30 kg/m², and large amount of free fluid on ultrasound increase the risk of conversion to laparotomy during laparoscopic management of ectopic pregnancy.