Dynamics of Staphylococcus aureus in patients and the hospital environment in a tertiary care hospital in the Netherlands.

BACKGROUND: The dynamics of Staphylococcus aureus in patients and the hospital environment are relatively unknown. We studied these dynamics in a tertiary care hospital in the Netherlands. METHODS: Nasal samples were taken from adult patients at admission and discharge. Isolates cultured from clinical samples taken before and during hospitalization from these patients were included. Environmental samples of patient rooms were taken over a three-year period. Finally, isolates from clinical samples from patients with an epidemiological link to S. aureus positive rooms were included. Staphylococcal protein A (spa) typing was performed. RESULTS: Nasal samples were taken from 673 patients. One hundred eighteen (17.5%) were positive at admission and discharge, 15 (2.2%) patients acquired S. aureus during hospitalization. Nineteen patients had a positive clinical sample during hospitalization, 15.9% of the S. aureus were considered as from an exogenous source. One hundred and forty (2.8%) environmental samples were S. aureus positive. No persistent contamination of surfaces was observed. Isolates were highly diverse: spa typing was performed for 893 isolates, identifying 278 different spa types, 161 of these spa types were observed only once. CONCLUSION: Limited transmission could be identified between patients and the hospital environment, and from patient-to-patient. Exogenous acquisition was assumed to occur in 15% of clinical samples. Environmental contamination was infrequent, temporarily, and coincided with the strain from the patient admitted to the room at that time. MRSA was rare and not found in the environment.

Universal screening or a universal risk assessment combined with risk-based screening for multidrug-resistant microorganisms upon admission: Comparing strategies.

OBJECTIVE: Timely identification of patients who carry multidrug-resistant microorganisms (MDRO) is needed to prevent nosocomial spread to other patients and to the hospital environment. We aimed to compare the yield of a universal screening strategy upon admission to the currently installed universal risk assessment combined with risk-based screening upon admission. METHODS: This observational study was conducted within a prospective cohort study. From January 1, 2018, until September 1, 2019, patients admitted to our hospital were asked to participate. Nasal and perianal samples were taken upon admission and checked for the presence of MDRO. The results of the universal risk assessment and risk-based screening were collected retrospectively from electronic health records. RESULTS: In total, 1017 patients with 1069 separate hospital admissions participated in the study. Universal screening identified 38 (3.6%) unknown MDRO carriers upon admission (37 individual patients), all carrying extended-spectrum beta-lactamase-producing Enterobacterales. For 946 of 1069 (88.5%) patients, both the universal risk assessment and universal screening were performed. For 19 (2.0%) admissions, ≥1 risk factor was identified. The universal risk assessment identified one (0.1%) unknown carrier, compared to 37 out of 946 carriers for the universal screening (P<0.001). Of the 37 carriers identified through the universal screening, 35 (94.6%) reported no risk factors. CONCLUSIONS: Our results show that in our low endemic setting, a universal screening strategy identified significantly more MDRO carriers than the currently implemented universal risk-assessment. When implementing a universal risk-assessment, risk factors should be carefully selected to be able to identify ESBL-E carriers. While the universal screening identified more MDRO carriers, further research is needed to determine the cost-effectiveness of this strategy.

Environmental contamination with highly resistant microorganisms after relocating to a new hospital building with 100% single-occupancy rooms: A prospective observational before-and-after study with a three-year follow-up.

INTRODUCTION: Inanimate surfaces within hospitals can be a source of transmission for highly resistant microorganisms (HRMO). While many hospitals are transitioning to single-occupancy rooms, the effect of single-occupancy rooms on environmental contamination is still unknown. We aimed to determine differences in environmental contamination with HRMO between an old hospital building with mainly multiple-occupancy rooms and a new hospital building with 100% single-occupancy rooms, and the environmental contamination in the new hospital building during three years after relocating. METHODS: Environmental samples were taken twice in the old hospital, and fifteen times over a three-year period in the new hospital. Replicate Organism Direct Agar Contact-plates (RODACs) were used to determine colony forming units (CFU). Cotton swabs premoistened with PBS were used to determine presence of methicillin-resistant Staphylococcus aureus, carbapenemase-producing Pseudomonas aeruginosa, highly resistant Enterobacterales, carbapenem-resistant Acinetobacter baumannii, and vancomycin-resistant Enterococcus faecium. All identified isolates were subjected to whole genome sequencing (WGS) using Illumina technology. RESULTS: In total, 4993 hospital sites were sampled, 724 in the old and 4269 in the new hospital. CFU counts fluctuated during the follow-up period in the new hospital building, with lower CFU counts observed two- and three years after relocating, which was during the COVID-19 pandemic. The CFU counts in the new building were equal to or surpassed the CFU counts in the old hospital building. In the old hospital building, 24 (3.3%) sample sites were positive for 49 HRMO isolates, compared to five (0.1%) sample sites for seven HRMO isolates in the new building (P < 0.001). In the old hospital, 89.8% of HRMO were identified from the sink plug. In the new hospital, 71.4% of HRMO were identified from the shower drain, and no HRMO were found in sinks. DISCUSSION: Our results indicate that relocating to a new hospital building with 100% single-occupancy rooms significantly decreases HRMO in the environment. Given that environmental contamination is an important source for healthcare associated infections, this finding should be taken into account when considering hospital designs for renovations or the construction of hospitals.

The effect of 100% single-occupancy rooms on acquisition of extended-spectrum beta-lactamase-producing Enterobacterales and intra-hospital patient transfers: a prospective before-and-after study.

BACKGROUND: Extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E) are a well-known cause of healthcare-associated infections. The implementation of single-occupancy rooms is believed to decrease the spread of ESBL-E. Additionally, implementation of single-occupancy rooms is expected to reduce the need for intra-hospital patient transfers. We studied the impact of a new hospital with 100% single-occupancy rooms on the acquisition of ESBL-E and on intra-hospital patient transfers. METHODS: In 2018, the Erasmus MC University Medical Center moved from an old, 1200-bed hospital with mainly multiple-occupancy rooms, to a newly constructed 522-bed hospital with 100% single-occupancy rooms. Adult patients admitted between January 2018 and September 2019 with an expected hospitalization of ≥ 48 h were asked to participate in this study. Perianal samples were taken at admission and discharge. Patient characteristics and clinical information, including number of intra-hospital patient transfers, were collected from the patients' electronic health records. RESULTS: Five hundred and ninety-seven patients were included, 225 in the old and 372 in the new hospital building. Fifty-one (8.5%) ESBL-E carriers were identified. Thirty-four (66.7%) patients were already positive at admission, of which 23 without recent hospitalization. Twenty patients acquired an ESBL-E, seven (3.1%) in the old and 13 (3.5%) in the new hospital building (P = 0.801). Forty-one (80.4%) carriers were only detected by the active screening performed during this study. Only 10 (19.6%) patients, six before and four during hospitalization, showed ESBL-E in a clinical sample taken on medical indication. Fifty-six (24.9%) patients were transferred to other rooms in the old hospital, compared to 53 (14.2%) in the new hospital building (P = 0.001). Intra-hospital patient transfers were associated with ESBL-E acquisition (OR 3.18, 95%CI 1.27-7.98), with increasing odds when transferred twice or more. CONCLUSION: Transitioning to 100% single-occupancy rooms did not decrease ESBL-E acquisition, but did significantly decrease the number of intra-hospital patient transfers. The latter was associated with lower odds on ESBL-E acquisition. ESBL-E carriers remained largely unidentified through clinical samples. TRIAL REGISTRATION: This study was retrospectively registered in the Dutch National Trial Register on 24-02-2020, with registration number NL8406.

Treatment of inoperable or metastatic paragangliomas and pheochromocytomas with peptide receptor radionuclide therapy using 177Lu-DOTATATE.

OBJECTIVES: Inoperable or metastatic paragangliomas (PGLs) and malignant pheochromocytomas (PCCs) are rare tumours with limited options for systemic treatment. Aim of this study was to assess the safety and efficacy of the radiolabelled somatostatin analogue (177LutetiumDOTA0-Tyr3)octreotate (177Lu-DOTATATE) for the treatment of PGLs and PCCs. METHODS: Patients with histologically proven inoperable or malignant PGLs and PCCs treated with 177Lu-DOTATATE at our centre were retrospectively analysed. Patients were treated with up to four cycles of 177Lu-DOTATATE with an intended dose of 7.4 Gb per cycle. Response was assessed with use of RECIST 1.1. RESULTS: Thirty patients were included: 17 with parasympathetic, 10 with sympathetic PGLs and 3 with PCCs. Grade 3/4 subacute haematotoxicity occurred in 6 (20%) of patients. A reversible subacute adverse event due to cardiac failure following possible catecholamine release occurred in two patients. Best tumour response was partial response in 7 (23%) and stable disease in 20 (67%), whereas 3 (10%) patients had progressive disease. In 20 patients with baseline disease progression, tumour control was observed in 17 (85%); the median progression-free survival was 91 months in patients with parasympathetic PGLs, 13 months in patients with sympathetic PGLs and 10 months in patients with metastatic PCCs. CONCLUSION: This study suggests that PRRT with 177Lu-DOTATATE is a safe and effective treatment option for patients with inoperable or malignant PGL and PCC.

Clinical outcome and morphologic determinants of mural thrombus in abdominal aortic endografts.

OBJECTIVE: Endograft mural thrombus has been associated with stent graft or limb thrombosis after endovascular aneurysm repair (EVAR). This study aimed to identify clinical and morphologic determinants of endograft mural thrombus accumulation and its influence on thromboembolic events after EVAR. METHODS: A prospectively maintained database of patients treated by EVAR at a tertiary institution from 2000 to 2012 was analyzed. Patients treated for degenerative infrarenal abdominal aortic aneurysms and with available imaging for thrombus analysis were considered. All measurements were performed on three-dimensional center-lumen line computed tomography angiography (CTA) reconstructions. Patients with thrombus accumulation within the endograft's main body with a thickness >2 mm and an extension >25% of the main body's circumference were included in the study group and compared with a control group that included all remaining patients. Clinical and morphologic variables were assessed for association with significant thrombus accumulation within the endograft's main body by multivariate regression analysis. Estimates for freedom from thromboembolic events were obtained by Kaplan-Meier plots. RESULTS: Sixty-eight patients (16.4%) presented with endograft mural thrombus. Median follow-up time was 3.54 years (interquartile range, 1.99-5.47 years). In-graft mural thrombus was identified on 30-day CTA in 22 patients (32.4% of the study group), on 6-month CTA in 8 patients (11.8%), and on 1-year CTA in 17 patients (25%). Intraprosthetic thrombus progressively accumulated during the study period in 40 patients of the study group (55.8%). Overall, 17 patients (4.1%) presented with endograft or limb occlusions, 3 (4.4%) in the thrombus group and 14 (4.1%) in the control group (P = .89). Thirty-one patients (7.5%) received an aortouni-iliac (AUI) endograft. Two endograft occlusions were identified among AUI devices (6.5%; overall, 0.5%). None of these patients showed thrombotic deposits in the main body, nor were any outflow abnormalities identified on the immediately preceding CTA. Estimated freedom from thromboembolic events at 5 years was 95% in both groups (P = .97). Endograft thrombus accumulation was associated with >25% proximal aneurysm neck thrombus coverage at baseline (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.1-3.3), neck length ≤ 15 mm (OR, 2.4; 95% CI, 1.3-4.2), proximal neck diameter ≥ 30 mm (OR, 2.4; 95% CI, 1.3-4.6), AUI (OR, 2.2; 95% CI, 1.8-5.5), or polyester-covered stent grafts (OR, 4.0; 95% CI, 2.2-7.3) and with main component "barrel-like" configuration (OR, 6.9; 95% CI, 1.7-28.3). CONCLUSIONS: Mural thrombus formation within the main body of the endograft is related to different endograft configurations, main body geometry, and device fabric but appears to have no association with the occurrence of thromboembolic events over time.

Sex differences in 30-day and 5-year outcomes after endovascular repair of abdominal aortic aneurysms in the EUROSTAR study.

OBJECTIVE: The purpose of this study was to determine the effect of sex on 30-day and long-term outcomes after elective endovascular aneurysm repair. METHODS: Patients entered into the European collaborators on stent graft techniques for abdominal aortic aneurysm repair (EUROSTAR) study formed the basis of our study. Data were analyzed by means of multivariable logistic regression for 30-day mortality and composite outcome of mortality, systemic complication, or conversion. Kaplan-Meier survival analyses were used to compare long-term survival and long-term event-free survival times between women and men. The log-rank test was used to test for differences. Cox proportional hazards regression was used to analyze survival and event-free survival (with end point mortality or reintervention). Multivariable analyses were adjusted for age, comorbidities, aneurysm characteristics, and treatment characteristics. RESULTS: There were 623 women and 8604 men available for analysis. No difference in 30-day mortality was demonstrated for women compared with men (odds ratio, 0.89; 95% confidence interval [CI], 0.48-1.67), but women did have a significantly higher cumulative incidence of the composite end point (odds ratio, 1.32; 95% CI, 1.05-1.66). The Kaplan-Meier curves demonstrated worse outcomes for both long-term survival (P = .05) and long-term event-free survival (P =.005). Survival analyses adjusting for covariates demonstrated a higher albeit nonsignificant difference in long-term mortality for women compared to men (hazard rate ratio, 1.21; 95% CI, 0.96-1.53) and a significant higher rate of the composite end point mortality or reintervention (hazard rate ratio, 1.28; 95% CI, 1.07-1.54). CONCLUSIONS: Women undergoing endovascular aortic repair have higher complication and reintervention rates compared with men, implying that the role of elective endovascular aneurysm repair in women needs to be examined more closely.

Conservative management of persistent aortocaval fistula after endovascular aortic repair.

Endovascular repair is a valid alternative for patients with abdominal aortic aneurysms. However, in patients with concomitant aortocaval fistulas, type II endoleaks may result in a persistent communication between the aneurysm sac and the inferior vena cava. In these patients, prompt closure of the persistent fistula has been advocated. We present a patient with an abdominal aortic aneurysm, with aortocaval fistula, who was managed endovascularly. Aneurysm sac shrinkage was observed despite persistent aortocaval communication due to type II endoleak. This case demonstrates that conservative management of type II endoleaks associated with persistent aortocaval fistulas is possible and may result in favorable aneurysm sac remodelling.

Adequate seal and no endoleak on the first postoperative computed tomography angiography as criteria for no additional imaging up to 5 years after endovascular aneurysm repair.

OBJECTIVE: Intensive image surveillance after endovascular aneurysm repair is generally recommended due to continued risk of complications. However, patients at lower risk may not benefit from this strategy. We evaluated the predictive value of the first postoperative computed tomography angiography (CTA) characteristics for aneurysm-related adverse events as a means of patient selection for risk-adapted surveillance. METHODS: All patients treated with the Low-Permeability Excluder Endoprosthesis (W. L. Gore & Assoc, Flagstaff, Ariz) at a tertiary institution from 2004 to 2011 were included. First postoperative CTAs were analyzed for the presence of endoleaks, endograft kinking, distance from the lowermost renal artery to the start of the endograft, and for proximal and distal sealing length using center lumen line reconstructions. The primary end point was freedom from aneurysm-related adverse events. Multivariable Cox regression was used to test postoperative CTA characteristics as independent risk factors, which were subsequently used as selection criteria for low-risk and high-risk groups. Estimates for freedom from adverse events were obtained using Kaplan-Meier survival curves. RESULTS: Included were 131 patients. The median follow-up was 4.1 years (interquartile range, 2.1-6.1). During this period, 30 patients (23%) sustained aneurysm-related adverse events. Seal length <10 mm and presence of endoleak were significant risk factors for this end point. Patients were subsequently categorized as low-risk (proximal and distal seal length ≥10 mm and no endoleak, n = 62) or high-risk (seal length <10 mm or presence of endoleak, or both; n = 69). During follow-up, four low-risk patients (3%) and 26 high-risk patients (19%) sustained events (P < .001). Four secondary interventions were required in three low-risk patients, and 31 secondary interventions in 23 high-risk patients. Sac growth was observed in two low-risk patients and in 15 high-risk patients. The 5-year estimates for freedom from aneurysm-related adverse events were 98% for the low-risk group and 52% for the high-risk group. For each diagnosis, 81.7 image examinations were necessary in the low-risk group and 8.2 in the high-risk group. CONCLUSIONS: Our results suggest that the first postoperative CTA provides important information for risk stratification after endovascular aneurysm repair when the Excluder endoprosthesis is used. In patients with adequate seal and no endoleaks, the risk of aneurysm-related adverse events was significantly reduced, resulting in a large number of unnecessary image examinations. Adjusting the imaging protocol beyond 30 days and up to 5 years, based on individual patients' risk, may result in a more efficient and rational postoperative surveillance.

Clinical outcome and morphologic analysis after endovascular aneurysm repair using the Excluder endograft.

OBJECTIVE: Long-term follow-up after endovascular aneurysm repair (EVAR) is very scarce, and doubt remains regarding the durability of these procedures. We designed a retrospective cohort study to assess long-term clinical outcome and morphologic changes in patients with abdominal aortic aneurysms (AAAs) treated by EVAR using the Excluder endoprosthesis (W. L. Gore and Associates, Flagstaff, Ariz). METHODS: From 2000 to 2007, 179 patients underwent EVAR in a tertiary institution. Clinical data were retrieved from a prospective database. All patients treated with the Excluder endoprosthesis were included. Computed tomography angiography (CTA) scans were retrospectively analyzed preoperatively, at 30 days, and at the last follow-up using dedicated tridimensional reconstruction software. For patients with complications, all remaining CTAs were also analyzed. The primary end point was clinical success. Secondary end points were freedom from reintervention, sac growth, types I and III endoleak, migration, conversion to open repair, and AAA-related death or rupture. Neck dilatation, renal function, and overall survival were also analyzed. RESULTS: Included were 144 patients (88.2% men; mean age, 71.6 years). Aneurysms were ruptured in 4.9%. American Society of Anesthesiologists classification was III/IV in 61.8%. No patients were lost during a median follow-up of 5.0 years (interquartile range, 3.1-6.4; maximum, 11.2 years). Two patients died of medical complications ≤ 30 days after EVAR. The estimated primary clinical success rates at 5 and 10 years were 63.5% and 41.1%, and secondary clinical success rates were 78.3% and 58.3%, respectively. Sac growth was observed in 37 of 142 patients (26.1%). Cox regression showed type I endoleak during follow-up (hazard ratio, 3.74; P = .008), original design model (hazard ratio, 3.85; P = .001), and preoperative neck diameter (1.27 per mm increase, P = .006) were determinants of sac growth. Secondary interventions were required in 32 patients (22.5%). The estimated 10-year rate of AAA-related death or rupture was 2.1%. Overall life expectancy after AAA repair was 6.8 years. CONCLUSIONS: EVAR using the Excluder endoprosthesis provides a safe and lasting treatment for AAA, despite the need for maintained surveillance and secondary interventions. At up to 11 years, the risk of AAA-related death or postimplantation rupture is remarkably low. The incidences of postimplantation sac growth and secondary intervention were greatly reduced after the introduction of the low-permeability design in 2004.

Radial force measurements in carotid stents: influence of stent design and length of the lesion.

PURPOSE: To assess the differences in radial force of carotid stents and whether the length of the lesion influences the measurements. MATERIALS AND METHODS: Different models of tapered stents of similar size (length, 30 mm) were used. The tapered nitinol Acculink, Protégé, and Cristallo Ideale carotid artery stents and the straight, braided Elgiloy carotid Wallstent were compared. A measurement device consisting of three film loops along the stent body connected to aluminium rods with copper strain gauges was developed. Five stents of each type were deployed within 3-mm stenoses in simulated long (26 mm) and short (8 mm) stenoses. RESULTS: In the short stenosis simulation, the greatest radial force was seen in the Protégé stent, at 3.14 N ± 0.45, followed by the Cristallo Ideale stent (1.73 N ± 0.51), Acculink (1.16 N ± 0.21), and Wallstent (0.84 N ± 0.10; P < .001). In the long stenosis simulation, peak radial force again was highest in the Protégé stent (1.67 N ± 0.37), but the Acculink stent was second (0.95 N ± 0.12) and the Wallstent third (0.80 N ± 0.06). The Cristallo Ideale stent, in contrast to the short stenosis simulation, produced the least radial force (0.44 N ± 0.13) in the long stenosis simulation (P = .001). CONCLUSIONS: Radial forces exerted by carotid stents vary significantly among stent designs. Differences between stent types are dependent on the length of the stenosis. An understanding of radial force is necessary for a well-considered choice of stent type in each individual patient.

Carotid endarterectomy for treatment of in-stent restenosis after carotid angioplasty and stenting.

OBJECTIVE: Carotid angioplasty and stenting (CAS) has emerged as an alternative for carotid endarterectomy (CEA) in the prevention of stroke. The benefit of the procedure, however, is hampered by a suggested higher incidence of in-stent restenosis (ISR) for CAS relative to CEA during follow-up. ISR management remains a challenge for clinicians. In this observational retrospective analysis, we evaluated the operative management of ISR by standard CEA with stent removal, including midterm follow-up in 15 patients. METHODS: The present analysis included 15 patients from three Dutch vascular centers who underwent CEA for symptomatic (n = 10) or hemodynamically significant (≥80%) asymptomatic ISR (n = 5). Median time between CAS and CEA was 18.3 months (range, 0-51 months). RESULTS: Standard CEA with stent removal was performed in all 15 patients. A Javid shunt was used in two procedures. One patient sustained an intraoperative minor ischemic stroke, with complete recovery during the first postoperative days. No neurologic complications occurred in the other 14 patients. Two patients required a reoperation to evacuate a neck hematoma. There were no peripheral nerve complications. After a median follow-up of 21 months (range, 3-100 months), all 15 patients remained asymptomatic and without recurrent restenosis (≥50%) on duplex ultrasound imaging. CONCLUSION: CEA with stent explantation for ISR after CAS seems an effective and durable therapeutic option, albeit with potential cerebral and bleeding complications, as in this study. The optimal treatment for carotid ISR, however, has yet to be defined.

Carotid artery stenting compared with endarterectomy in patients with symptomatic carotid stenosis (International Carotid Stenting Study): an interim analysis of a randomised controlled trial.

BACKGROUND: Stents are an alternative treatment to carotid endarterectomy for symptomatic carotid stenosis, but previous trials have not established equivalent safety and efficacy. We compared the safety of carotid artery stenting with that of carotid endarterectomy. METHODS: The International Carotid Stenting Study (ICSS) is a multicentre, international, randomised controlled trial with blinded adjudication of outcomes. Patients with recently symptomatic carotid artery stenosis were randomly assigned in a 1:1 ratio to receive carotid artery stenting or carotid endarterectomy. Randomisation was by telephone call or fax to a central computerised service and was stratified by centre with minimisation for sex, age, contralateral occlusion, and side of the randomised artery. Patients and investigators were not masked to treatment assignment. Patients were followed up by independent clinicians not directly involved in delivering the randomised treatment. The primary outcome measure of the trial is the 3-year rate of fatal or disabling stroke in any territory, which has not been analysed yet. The main outcome measure for the interim safety analysis was the 120-day rate of stroke, death, or procedural myocardial infarction. Analysis was by intention to treat (ITT). This study is registered, number ISRCTN25337470. FINDINGS: The trial enrolled 1713 patients (stenting group, n=855; endarterectomy group, n=858). Two patients in the stenting group and one in the endarterectomy group withdrew immediately after randomisation, and were not included in the ITT analysis. Between randomisation and 120 days, there were 34 (Kaplan-Meier estimate 4.0%) events of disabling stroke or death in the stenting group compared with 27 (3.2%) events in the endarterectomy group (hazard ratio [HR] 1.28, 95% CI 0.77-2.11). The incidence of stroke, death, or procedural myocardial infarction was 8.5% in the stenting group compared with 5.2% in the endarterectomy group (72 vs 44 events; HR 1.69, 1.16-2.45, p=0.006). Risks of any stroke (65 vs 35 events; HR 1.92, 1.27-2.89) and all-cause death (19 vs seven events; HR 2.76, 1.16-6.56) were higher in the stenting group than in the endarterectomy group. Three procedural myocardial infarctions were recorded in the stenting group, all of which were fatal, compared with four, all non-fatal, in the endarterectomy group. There was one event of cranial nerve palsy in the stenting group compared with 45 in the endarterectomy group. There were also fewer haematomas of any severity in the stenting group than in the endarterectomy group (31 vs 50 events; p=0.0197). INTERPRETATION: Completion of long-term follow-up is needed to establish the efficacy of carotid artery stenting compared with endarterectomy. In the meantime, carotid endarterectomy should remain the treatment of choice for patients suitable for surgery. FUNDING: Medical Research Council, the Stroke Association, Sanofi-Synthélabo, European Union.

Carotid artery stenting versus endarterectomy in relation to perioperative myocardial ischemia, troponin T release and major cardiac events.

BACKGROUND: Carotid artery stenting (CAS) is less invasive than endarterectomy. This study examined differences in perioperative myocardial ischemia, troponin T release and clinical cardiac events in patients undergoing CAS compared with endarterectomy. METHODS: In an observational study, CAS was performed in 24 and carotid endarterectomy in 44 patients. Before surgery, clinical risk factors were noted and dobutamine stress echocardiography was performed for cardiac risk assessment. Perioperative continuous 72-h 12-lead electrocardiographic monitoring was used for myocardial ischemia detection. Troponin T (>0.03 ng/ml) was measured on postoperative days 1, 3, 7 or before discharge. Cardiac events (cardiac death or Q-wave myocardial infarction) were noted during hospital stay and during follow-up (mean: 1.2 years). RESULTS: No significant differences were observed between patients with CAS and endarterectomy in terms of baseline clinical characteristics, dobutamine stress echocardiography results and cardiovascular medication. Perioperative myocardial ischemia was detected in nine patients (13%), perioperative troponin T release in seven patients (10%), early cardiac events in one patient (1%) and late cardiac events in three patients (4%). Significantly less perioperative myocardial ischemia was observed in patients with CAS compared with endarterectomy (0 versus 21%, P=0.02). Troponin T release was also significantly lower in CAS, compared with endarterectomy (0 versus 16%, P=0.04). Early (0 versus 2%, P=0.5) and late (0 versus 7%, P=0.2) cardiac events were lower after CAS, compared with endarterectomy, although these differences were not significant. CONCLUSION: CAS is associated with a lower incidence of perioperative myocardial ischemia and troponin T release, compared with endarterectomy.

Diffusion-weighted imaging to compare different cerebral protection devices in carotid artery stenting.

AIMS: Carotid artery stenting (CAS) is commonly performed with cerebral protection devices. New hyperintense lesions on diffusion-weighted MR imaging (DWI) were used to compare different cerebral protection devices. METHODS AND RESULTS: Patients (n=33) with high-grade symptomatic carotid stenosis were treated with CAS. Two different methods of cerebral embolic protection were used. In 23 patients, a filter device was placed in the distal internal carotid artery. In 10 patients a protection system based on the reversed-flow principle was used. DWI was performed before and after CAS. The number and volume of new hyperintense lesions in the ipsilateral hemisphere were assessed.No stroke or death was recorded. Twenty-three new hyperintense lesions in the ipsilateral cerebral hemisphere were recorded on the post-treatment DWI-series after stent placement in 12 of the 33 procedures (36%). In 8 of the 23 procedures (35%) performed with a filter device and in 4 of the 10 procedures (40%) performed with the reversed-flow device new hyperintense lesions were revealed (13 and 10, respectively). No significant differences were found in the number of lesions and lesion load. The volume per lesion was significantly smaller in the patient group treated with reversed-flow device in comparison to the patient group treated with a filter device (median 0,048 mm3 and 0,013 mm3, respectively; p=0.03). CONCLUSION: This non-randomised study revealed no difference in new subclinical ischaemic lesions in the ipsilateral hemisphere between procedures performed with filter devices and procedures performed with embolic protection using the reversed-flow principle.

Endovascular repair versus open surgery in patients with ruptured abdominal aortic aneurysms: clinical outcomes with 1-year follow-up.

OBJECTIVE: To compare the clinical outcomes of treatment after endovascular repair and open surgery in patients with ruptured infrarenal abdominal aortic aneurysms (AAAs), including 1-year follow-up. METHODS: All consecutive conscious patients with ruptured infrarenal AAAs who presented to our tertiary care teaching hospital between January 1, 2001, and December 31, 2005, were included in this study (n = 55). Twenty-six patients underwent endovascular repair, and 29 patients underwent open surgery. Patients who were hemodynamically too unstable to undergo a computed tomography angiography scan were excluded. Outcomes evaluated were intraoperative mortality, 30-day mortality, systemic complications, complications necessitating surgical intervention, and mortality and complications during 1-year follow-up. The statistical tests we used were the Student t test, chi2 test, Fisher exact test, and Mann-Whitney U test (two sided; alpha = .05). RESULTS: Thirty-day mortality was 8 (31%) of 26 patients who underwent endovascular repair and 9 (31%) of 29 patients who underwent open surgery (P = .98). Systemic complications and complications necessitating surgical intervention during the initial hospital stay were similar in both treatment groups (8/26 [31%] and 5/26 [19%] for endovascular repair, respectively, and 9/29 [31%] and 8/29 [28%] for open surgery, respectively; P > .40). During 1-year follow-up, two patients initially treated with endovascular repair died as a result of non-aneurysm-related causes; no death occurred in the open surgery group. Complications during 1-year follow-up were 1 (5%) of 20 for endovascular repair and 4 (16%) of 25 for open surgery (P = .36). CONCLUSIONS: On the basis of our study with a highly selected population, the mortality and complication rates after endovascular repair may be similar compared with those after open surgery in patients treated for ruptured infrarenal AAAs.

In vivo characterization and quantification of atherosclerotic carotid plaque components with multidetector computed tomography and histopathological correlation.

OBJECTIVE: In a previous in vitro study we have demonstrated that atherosclerotic plaque components can be characterized with multidetector computed tomography (MDCT) based on differences in Hounsfield values (HV). Now we evaluated the use of MDCT in vivo to characterize and quantify atherosclerotic carotid plaque components compared with histology as reference standard. METHODS AND RESULTS: Fifteen symptomatic patients with carotid stenosis (>70%) underwent MDCT angiography before carotid endarterectomy (CEA). From each CEA specimen 3 histological sections and corresponding MDCT images were selected. The HV of the major plaque components were assessed. The measured HV were: 657+/-416HU, 88+/-18HU, and 25+/-19HU for calcifications, fibrous tissue, and lipid core, respectively. The cut-off value to differentiate lipid core from fibrous tissue and fibrous tissue from calcifications was based on these measurements and set at 60 HU and 130 HU, respectively. Regression plots showed good correlations (R2>0.73) between MDCT and histology except for lipid core areas, which had a good correlation (R2=0.77) only in mildly calcified (0% to 10%) plaques. CONCLUSIONS: MDCT is able to quantify total plaque area, calcifications, and fibrous tissue in atherosclerotic carotid plaques in good correlation with histology. Lipid core can only be adequately quantified in mildly calcified plaques.

Acute abdominal aortic aneurysms: cost analysis of endovascular repair and open surgery in hemodynamically stable patients with 1-year follow-up.

PURPOSE: To retrospectively assess the in-hospital and 1-year follow-up costs of endovascular aneurysm repair and conventional open surgery in patients with acute infrarenal abdominal aortic aneurysm (AAA) by using a resource-use approach. MATERIALS AND METHODS: Institutional Review Board approval was obtained, and informed consent was waived. In-hospital costs for all consecutive patients (61 men, six women; mean age, 72.0 years) who underwent endovascular repair (n = 32) or open surgery (n = 35) for acute infrarenal AAA from January 1, 2001, to December 31, 2004, were assessed by using a resource-use approach. Patients who did not undergo computed tomography before the procedure were excluded from analysis. One-year follow-up costs were complete for 30 patients who underwent endovascular repair and for 34 patients who underwent open surgery. Costs were assessed from a health care perspective. Mean costs were calculated for each treatment group and were compared by using the Mann-Whitney U test (alpha = .05). The influence of clinical variables on the total in-hospital cost was investigated by using univariate and multivariate analyses. Costs were expressed in euros for the year 2003. RESULTS: Sex, age, and comorbidity did not differ between treatment groups (P > .05). The mean total in-hospital costs were lower for patients who underwent endovascular repair than for those who underwent open surgery (euro20 767 vs euro35 470, respectively; P = .004). The total costs, including those for 1-year follow-up, were euro23 588 for patients who underwent endovascular repair and euro36 448 for those who underwent open surgery (P = .05). The results of multivariate analysis indicated that complications had a significant influence on total in-hospital cost; patients who had complications incurred total in-hospital costs that were 2.27 times higher than those for patients who had no complications. CONCLUSION: Total in-hospital costs and total overall costs, which included 1-year follow-up costs, were lower in patients with acute AAA who underwent endovascular repair than in those who underwent open surgery.

Embolic protection filters for carotid stenting: differences in flow obstruction depending on filter construction.

PURPOSE: To investigate the pressure gradient and degree of flow reduction associated with embolus protection filters for carotid stenting in an in vitro experiment. METHODS: Three filter devices with a perforated membrane design and one wire mesh type filter were tested. At a pressure of 70 mmHg, the flow reduction and pressure gradient were measured in a 5-mm tube using blood-mimicking fluid. RESULTS: The pressure gradient in the wire mesh filter was 1.65+/-0.49 mmHg (95% CI 1.32 to 1.86). The mean pressure gradient in the perforated membrane filters was 6.88+/-2.62 mmHg (95% CI 6.22 to 7.55, p<0.0001). There was also a significant correlation between pressure gradient and flow reduction (r=-0.77, p<0.01). CONCLUSION: Embolic protection filters cause a pressure gradient and obstruct blood flow. This effect is marked in perforated membrane filters and almost absent in the wire mesh filter.