Assessing the institutional learning curve for pararenal aortic repair using the fenestrated Anaconda endograft

Objective

Custom-made fenestrated aortic endografts allow exclusion of pararenal aortic aneurysms while maintaining blood flow to aortic branches. Meticulous device planning and precise deployment of the main body are essential to allow successful cannulation of the fenestrations. This study investigates whether a learning curve can be observed with more reliable cannulation and connection of fenestrations over time at a single department of vascular and endovascular surgery with multiple surgeons trained to use the device.

Methods

A retrospective analysis of data from all patients undergoing primary fenestrated endovascular aneurysm repair during the study period was performed. Outcome measures included case volume and average number of fenestrations over time, average fluoroscopy dose area product per calendar year and primary unconnected fenestration and 30-day mortality rates.

Results

Between 1 January 2013 and 31 December 2016, 89 patients with no history of endovascular aneurysm repair underwent fenestrated endovascular aneurysm repair at our institution. The number of fenestrations per case increased over time, averaging 2.6 in 2013 and 3.3 in 2016. Primary unconnected fenestration and 30-day mortality rates were 5.6%. Primary-assisted technical success was 93.3%, secondary-assisted technical success was 94.4%. Fluoroscopy dose area product declined over the study period. Thirty-day mortality and primary unconnected fenestration rates did not significantly change over the study period.

Conclusion

Albeit the reduction in lethal complications and primary technical success rates were not statistically significant, a lower percentage of unconnected fenestrations and 30-day mortality per calendar year were observed over time. At the same time, an increasing complexity of performed cases, as reflected by an increasing number of fenestrations per case, was observed. Complications associated with this complex endovascular procedure are potentially lethal and remain an unfortunate reality and may not be entirely dependent on overcoming a learning curve. A higher volume of cases performed over the study period and a reduction in fluoroscopy use can be considered a representation of the institutional development and learning curve for the Anaconda fenestrated endograft at a department with prior complex endovascular aortic repair experience, but due to limitations of the current retrospective observation, deserve further consideration in future trials, ideally designed in a prospective fashion.

Randomized controlled trial comparing the combination of a polymeric membrane dressing plus negative pressure wound therapy against negative pressure wound therapy alone: The WICVAC study

Negative pressure wound therapy (NPWT) is the treatment of choice for chronic wounds; yet, it is associated with considerable workload. Prompted by its nonadhesive and wound-healing properties, this study investigated the effect of an additional polymeric membrane interface dressing (PMD; PolyMem WIC) in NPWT. From October 2011 to April 2013, 60 consecutive patients with chronic leg wounds or surgical site infections after revascularization of lower extremities were randomly allocated to either treatment with conventional NPWT (control arm) or NPWT with an additional PMD (intervention arm). The primary outcome was wound healing achieved within 30 days, the secondary endpoints included: number of days between dressing changes, wound-related pain, cost efficiency, and occurrence of adverse events (ClinTrials.gov Identifier: NCT02399722). Forty-seven patients completed follow-up. No difference in wound healing was observed (p > 0.05) between both study arms. The additional PMD allowed significantly longer wearing times (days) between dressing changes (intervention: 8.8 ± 0.5, control: 4.8 ± 0.2; p < 0.001). Pain was slightly higher in patients randomized to NPWT alone (VAS score: 4.8 ± 2.9) compared to NPWT + PMD (VAS score: 3.0 ± 2.9, p = 0.063). No wound infections were observed. Costs were reduced by 34% per patient in the intervention arm. These results suggest that the combination of NPWT and an additional interface PMD is a safe and economic method for the treatment of chronic wounds, which requires significantly fewer dressing changes for a comparable wound healing.

A prospective, randomised study of a novel transforming methacrylate dressing compared with a silver-containing sodium carboxymethylcellulose dressing on partial-thickness skin graft donor sites in burn patients

This prospective, randomised study compares a new transforming methacrylate dressing (TMD) with a silver-containing carboxymethylcellulose dressing (CMC-Ag) after application to split-thickness skin graft (STSG) donor sites. This was an unblinded, non-inferiority, between-patient, comparison study that involved patients admitted to a single-centre burn unit who required two skin graft donor sites. Each patient's donor sites were covered immediately after surgery: one donor site with TMD and the other with CMC-Ag. The donor sites were evaluated until healing or until 24 days post-application, whichever came first. Study endpoints were time to healing, daily pain scores, number of dressing changes, patient comfort and physicians' and patients' willingness to use the dressings in the future. Nineteen patients had both the dressings applied. No statistically significant difference was noted in time to healing between the two dressings (14·2 days using TMD compared with 13·2 days using CMC-Ag). When pain scores were compared, TMD resulted in statistically significantly less pain at three different time periods (2-5 days, 6-10 days and 11-15 days; P < 0·001 at all time periods). Patients also reported greater comfort with TMD (P < 0·001). Users rated TMD as being less easy to use because of the time and technique required for application. Reductions in pain and increased patient comfort with the use of the TMD dressing, compared with CMC-Ag, were seen as clinical benefits as these are the major issues in donor site management.

Homocysteine improves risk stratification in patients undergoing endarterectomy for asymptomatic internal carotid artery stenosis

BACKGROUND AND PURPOSE

A limited life expectancy reduces the benefit from carotid endarterectomy (CEA) for treatment of asymptomatic internal carotid artery stenosis. The aim of this study was to assess homocysteine as stratifying biomarker to improve prediction of postoperative survival.

METHODS

This was a prospective, nonrandomized case series from 2003 to 2012. Two hundred and fourteen consecutive patients (<75 years, n=130; ≥75 years, n=84) undergoing CEA for their asymptomatic internal carotid artery stenosis were observed for 8.5 years for the occurrence of death after CEA as primary end point (EC-nr: 04-067-0604). Homocysteine and major cardiovascular risk factors were used for computation of prognostic indices. Cumulative survival of prognostic indices-based quintiles was estimated by Kaplan-Meier curves.

RESULTS

Total homocysteine had a significant effect on postoperative survival (P<0.0001). Total homocysteine-based quintiles of prognostic indices showed a better prediction of the survival of the patients than age alone. This caused reclassification of 17 patients (20.2%)>75 years as fit for surgery, but also indicated a high risk for 19 patients (14.6%)<75 years. In the majority (79.8%) of patients aged>75 years, statistically, CEA could not be advised because of a significantly reduced 5-year survival rate.

CONCLUSIONS

High plasma homocysteine levels suggest that older patients with asymptomatic carotid stenosis might rather benefit from intensive medical therapy than from CEA.

Austrian national carotid intervention numbers prompt improvement in secondary stroke prevention

BACKGROUND

As recent data suggest a variable benefit of carotid endarterectomy (CEA) or stenting (CAS), a careful selection of patients is mandatory for efficient stroke prevention. This retrospective study analyzed carotid intervention rates from 1999-2008 in Austria. The aim was to assess whether interventions for carotid stenosis were performed with respect to epidemiological trends and published data taking into account intervention type, age and gender.

METHODS

Intervention numbers for internal carotid artery (ICA)-stenosis from a 10 years period (1999 to 2008) were retrieved from the national Austrian registry for hospital funding. Patients were grouped by gender, age (0-64, 65-74, older than 75 years) and intervention type.

RESULTS

CEA rates amounted to 32.2±1.4 per 100000 persons annually (female: 22.1±0.7, male: 43.0±2.3). Each year 9.1 CAS±1.6 per 100000 Austrians were performed (female: 9.3±1.8, male 8.9±1.7). CAS numbers increased (P<0.05), whereas CEA numbers stagnated, especially in older age groups. Women were more likely to undergo CAS than CEA compared to men.

CONCLUSION

Relative intervention rates for carotid stenosis have rather stagnated, although stroke incidence increases continuously in an overaging society. Despite controversial data, CAS rates have been rising constantly in elderly women. Secondary stroke prevention in Austria can be improved by a careful selection of future patients, especially with regard to female gender and type of intervention.

Indications and techniques for emergency carotid interventions

Mutual understanding exists among specialists of neurology, interventional radiology and vascular surgery concerning the need of interventional treatment for patients with symptomatic carotid artery stenosis. However, identification of individuals that will most likely benefit from treatment, timing of the intervention and selection of treatment mode continue to be a matter of intense debate. The aim of this manuscript was to discuss the changing attitude to this high-risk population and present evidence that points towards a resolute, fast-track approach.

Local anesthesia and exposure for carotid endarterectomy: background and technical realization

While carotid endarterectomy is an established method for the treatment of symptomatic as well as high-grade asymptomatic carotid artery stenoses, there is a considerable variation concerning the kind of anesthesia used as well as technical details of the operation. In the present article differing arguments on local versus general anesthesia as well as a transverse versus a longitudinal skin incision will be discussed. Furthermore, possible access routes to the carotid bifurcation, the retrojugular compared to the ventrojugular approach, will be presented in detail.

Comparison of enoxaparin and unfractionated heparin in endovascular interventions for the treatment of peripheral arterial occlusive disease: a randomized controlled trial

BACKGROUND

Although unfractionated heparin (UFH) is an effective antithrombotic agent in endovascular interventions for the treatment of peripheral occlusive arterial disease (PAOD), it produces a highly variable anticoagulant response. Intravenous (i.v.) enoxaparin might be an effective and safe alternative.

PATIENTS AND METHODS

In a prospective, open-label, randomized, single-center trial, 210 patients with PAOD (Fontaine stage IIb to IV) were randomly assigned in a 1 (UFH): 2 (enoxaparin) fashion to receive an i.v. bolus of 60 units UFH per kg body weight or 0.5 mg enoxaparin per kg body weight, respectively, before endovascular intervention. The primary composite endpoint assessed the clinical performance of enoxaparin by comparing the peri-interventional rate of thromboembolia/occlusion (efficacy) of endovascularly reconstructed areas, of bleeding according to the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO) criteria (safety) and of any necessary re-intervention for any percutaneous transluminal angioplasty (PTA)-related bleeding. The secondary endpoint evaluated anti-factor (F)Xa levels during intervention.

RESULTS

The primary composite endpoint showed a better performance of enoxaparin (10.5% vs. 2.5% absolute difference - 8.0%; P < 0.05). The concomitant use of acetylsalicylic acid (ASA) significantly (P < 0.05) increased the risk of a complication in the UFH group, but not in the enoxaparin group. Within 15 min, anti-Xa levels were reached by 63.7% of patients treated with enoxaparin and only by 39.1% with UFH.

CONCLUSION

Enoxaparin has a better performance than UFH in endovascular interventions for the treatment of PAOD. In patients with concomitant use of ASA, the risk of complications with UFH increases significantly compared with enoxaparin.

N-terminal pro B-type natriuretic peptide (NT pro-BNP) is a predictor of long-term survival in male patients of 75 years and older with high-grade asymptomatic internal carotid artery stenosis

BACKGROUND

Carotid endarterectomy (CEA) is commonly performed for asymptomatic high-grade internal carotid artery (ICA) stenosis to prevent stroke. However, despite advancing age of the society, for patients older than 75 years, there is no recommendation by the European guidelines for CEA, as this age group might not benefit from this intervention due to a limited life expectancy.

OBJECTIVE

We assessed N-terminal pro B-type natriuretic peptide (NT pro-BNP) as a predictive marker for long-term survival in this particular patient population in order to stratify patients for an improved surgical outcome.

METHODS

In a nonrandomized single-center clinical trial, we prospectively studied mortality rates of 205 consecutive patients (80 women, 125 men; mean age, 75 ± 10 years) with asymptomatic high-grade ICA stenosis in relation to preoperative plasma NT pro-BNP levels. We estimated cumulative survival over 5 years by Kaplan-Meier curves and established a proportional hazard-model by Cox regression.

RESULTS

In male patients, higher levels of preoperative NT pro-BNP levels were associated with a significantly increased long-term mortality. Those 75 years or older had the same survival rate as younger patients, if NT pro-BNP levels were low, making them thus eligible for CEA.

CONCLUSIONS

The results of our study suggest that preoperative plasma levels of NT pro-BNP are a valuable tool for the stratification of male patients. Male patients older than 75 years with low levels of NT pro-BNP should be referred for carotid revascularization, as they will most likely enjoy the benefit of surgery.