Comparison of femoro-popliteal plain balloon angioplasty for chronic limb threatening ischaemia in the BASIL trial and in a UK contemporary series

BACKGROUND

Since the turn of the millennium there has been a world-wide trend towards an endovascular first where possible revascularisation strategy for chronic limb threatening (CLTI). There is concern that this may be inappropriate and can result in net patient harm. The aim of this study, therefore, is to compare important clinical outcomes following femoro-popliteal plain balloon angioplasty (FP-PBA), with selective use of bare metal stents (BMS), in a contemporary series (CS) of patients treated in our unit between 2009 and 2014 with those observed following FP-PBA +/- BMS in the UK NIHR HTA-funded Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL-1, B1) trial (treated 1999-2004).

METHODS

Baseline and clinical outcome data (amputation free survival, AFS; overall survival, OS; limb salvage, LS; freedom from re-intervention, FF-R; freedom from major adverse limb events, FF-MALE) were obtained from prospectively gathered hospital data and B1 trial case record forms.

RESULTS

There were 237 CS and 218 B1 patients. CS patients were older (77 vs 73 years, p=.0002). B1 patients were more likely to be current smokers, less likely to be on best medical therapy, and underwent more extensive endovascular interventions. CS had more hospital admissions (4 vs 2, p<.0001) before they reached their primary endpoint (AFS). Immediate technical success was non-significantly higher in the CS patients (87% vs 83%, p=0.2). BMS were used in 20 (8%) CS and 2 (1%) B1 patients (p=.0002). AFS (HR = 0.64, 95%CI: 0.49 to 0.82, p = .0005) and OS (HR = 0.58, 95% CI: 0.44 to 0.76, p = .0001) were significantly worse in the CS cohort. There was no significant difference in LS, FF-R or FF-MALE.

CONCLUSIONS

CLTI patients managed in our unit (2009-2014) by means of a FP-PBA +/- BMS first where possible revascularisation strategy experience significantly worse AFS and OS than patients treated with FP-PBA +/- BMS in the B1 trial ten years earlier (1999-2004).

A Comparison of Outcomes in Patients with Infrapopliteal Disease Randomised to Vein Bypass or Plain Balloon Angioplasty in the Bypass vs. Angioplasty in Severe Ischaemia of the Leg (BASIL) Trial

OBJECTIVE

The aim was to compare outcomes in a subgroup of patients with infrapopliteal (IP) disease randomised to infrapopliteal vein bypass (VB) or plain balloon angioplasty (PBA) in the original BASIL trial.

METHODS

A comparison of outcomes from patients randomised to VB or PBA undergoing revascularisation for severe limb ischaemia (SLI) because of IP disease with or without femoropopliteal disease. Data were extracted from case report forms from the BASIL trial. The primary outcome was amputation free survival (AFS); secondary outcomes included overall survival (OS), 30 day mortality and morbidity, freedom from arterial re-intervention, immediate technical success, repeat and crossover interventions, length of hospital stay, and quality of revascularisation.

RESULTS

A total of 104 patients were identified in the BASIL study with IP disease, 56 randomised to IP VB, and 48 to IP PBA. Groups were similar at baseline except for more chronic kidney disease and non-steroidal anti-inflammatory drug use in the VB group, and more previous surgical arterial intervention and antihypertensive use in the PBA group. There were no statistically significant differences in AFS or OS; however, clinically important trends were apparent in favour of a VB first strategy. Patients allocated to VB demonstrated significantly quicker relief of rest pain when compared with PBA (p = .005), but no significant differences in improved tissue healing. Median length of index hospital admission was significantly greater in the VB than in the PBA group (18 vs. 10 days, p < .0001) but there was no difference between the two groups in median total hospital stay between randomisation and the primary endpoint (VB 43.5 vs. PBA 42 days).

CONCLUSIONS

Further randomised trials, like BASIL-2 and BEST-CLI, are required to determine whether patients with severe limb ischaemia who require IP revascularisation and who are suitable for VB should have bypass or endovascular intervention as their primary revascularisation procedure.

Comparison of Minitek Anaerobe II, API An-Ident, and RapID ANA systems for identification of Clostridium difficile

Three commercial anaerobic systems, Minitek (BBL Microbiology Systems, Cockeysville, MD), API An-Ident (Analytab Products, Plainview, NY), and RapID ANA (Innovative Diagnostic Systems, Decatur, GA) were evaluated for ability to identify 45 Clostridium difficile isolates accurately. Minitek correctly identified 66% of C. difficile isolates to species, 27% were incompletely identified, and 7% were misidentified. Most of the discrepancies with Minitek were due to false negative biochemical results. API An-Ident correctly identified 9% C. difficile isolates to species, 89% were incompletely identified, and 2% were misidentified. Most of the API An-Ident discrepancies were due to the data base, which distinguished poorly between C. difficile, Clostridium hastiforme, and Clostridium sporogenes. RapID ANA correctly identified 100% of C. difficile isolates.

The microstructure of dentine in taxonomic and phylogenetic studies

Traditionally, physical anthropologists have focused their dental studies on features of teeth that can be observed with the unaided eye, measured with calipers, or observed with light microscopes. With the advent of the scanning electron microscope, there has been renewed interest in the use of the microstructure of enamel in phylogenetic reconstruction and taxonomic classification. The microstructure of dentine has received far less research attention than has enamel although several investigators have proposed that dentine has taxon specificity. We report the first results of a study in which we investigated the taxon specificity of dentine. In our study, we exposed the dentinal tubules on the mesial root surfaces of 12 Canis, 11 Papio, and 12 Homo mandibular first molars and compared tubule density and pattern among the three taxa. Based on these parameters, 91.43% of the teeth were correctly identified as being dog, baboon, or human, respectively. We conclude that dentine has taxon-specific structural characteristics, which can be used in anthropological investigations. To our knowledge, this is the first comparative study of the micro-structure of teeth utilizing statistical analysis.