Guidance for the gastrointestinal evaluation and management of iron deficiency in Sub-Saharan Africa

BACKGROUND

Over 30% of the world's population is anaemic, with a significant proportion of these being iron deficient. As iron deficiency (ID) anaemia in men and post-menopausal women is mostly caused by gastrointestinal blood loss or malabsorption, the initial evaluation of a patient with ID anaemia involves referral to a gastroenterologist. The current drive towards patient blood management in sub-Saharan Africa (SSA)prescribes that we regulate not only the use of blood transfusion but also the management of patients in whom the cause of iron loss or inadequate iron absorption is sought. Recommendations have been developed to: (i) aid clinicians in the evaluation of suspected gastrointestinal iron loss and iron malabsorption, and often a combination of these; (ii) improve clinical outcomes for patients with gastrointestinal causes of ID; (iii) provide current, evidence-based, context-specific recommendations for use in the management of ID; and (iv) conserve resources by ensuring rational utilisation of blood and blood products.

METHOD

Development of the guidance document was facilitated by the Gastroenterology Foundation of Sub-Saharan Africa and the South African Gastroenterology Society. The consensus recommendations are based on a rigorous process involving 21 experts in gastroenterology and haematology in SSA. Following discussion of the scope and purpose of the guidance document among the experts, an initial review of the literature and existing guidelines was undertaken. Thereafter, draft recommendation statements were produced to fulfil the outlined purpose of the guidance document. These were reviewed in a round-table discussion and were subjected to two rounds of anonymised consensus voting by the full committee in an electronic Delphi exercise during 2022 using the online platform, Research Electronic Data Capture. Recommendations were modified by considering feedback from the previous round, and those reaching a consensus of over 80% were incorporated into the final document. Finally, 44 statements in the document were read and approved by all members of the working group.

CONCLUSION

The recommendations incorporate six areas, namely: general recommendations and practice, Helicobacter pylori, coeliac disease, suspected small bowel bleeding, inflammatory bowel disease, and preoperative care. Implementation of the recommendations is aimed at various levels from individual practitioners to healthcare institutions, departments and regional, district, provincial and national platforms. It is intended that the recommendations spur the development of centre-specific guidelines and that they are integrated with the relevant patient blood management protocols. Integration of the recommendations is intended to promote optimal evaluation and management of patients with ID, regardless of the presence of anaemia.

Motifs in SARS-CoV-2 evolution

We present a novel framework enhancing the prediction of whether novel lineage poses the threat of eventually dominating the viral population. The framework is based purely on genomic sequence data, without requiring prior established biological analysis. Its building blocks are sets of coevolving sites in the alignment (motifs), identified via coevolutionary signals. The collection of such motifs forms a relational structure over the polymorphic sites. Motifs are constructed using distances quantifying the coevolutionary coupling of pairs and manifest as coevolving clusters of sites. We present an approach to genomic surveillance based on this notion of relational structure. Our system will issue an alert regarding a lineage, based on its contribution to drastic changes in the relational structure. We then conduct a comprehensive retrospective analysis of the COVID-19 pandemic based on SARS-CoV-2 genomic sequence data in GISAID from October 2020 to September 2022, across 21 lineages and 27 countries with weekly resolution. We investigate the performance of this surveillance system in terms of its accuracy, timeliness, and robustness. Lastly, we study how well each lineage is classified by such a system.

Predicting metalwork following posterior fixation of thoracolumbar fractures

OBJECTIVES

Surgical fusion through posterior instrumentation and pedicle screw placement is a long established method for stabilising traumatic spinal fractures. Post-surgical complications include infection and metal work failure, the most common aetiology of which is pedicle screw fracture. Metal work failure rates vary from 15% to 60%. Research relating to factors which predict metal work failure in post-traumatic thoracolumbar spinal fixation is lacking. This study aimed to identify potential risk factors for metalwork failure in patients who had posterior fixation for traumatic thoracolumbar spine fractures.

METHODS

This retrospective cohort analysis was conducted by interrogating the hospital database for neurosurgical post-traumatic thoracolumbar fixation cases between 2015 and 2018 with at least 2 years follow up. Data was collected through electronic medical notes and PACS. Nineteen different patient factors (gender, age, mechanism of injury, presence of concomitant injury spinal or extra-spinal injury, pedicle cross-sectional area, pedicle cancellous bone density, pedicle total bone density, vertebral body bone density, erector spinae muscle density and lumbar spine subcutaneous fat thickness, Charlson comorbidity index, fracture location, surgical approach, long/short segment fixation, whether decompression was done, whether the index level was fixed, and presence of wound infection) were compared.

RESULTS

We identified 92 patients with 97 operations, and 9 cases of metal work failure. Two factors were statistically significantly associated with metal work failure: Post-operative wound infection (p = 0.029) and lumbar spine fat thickness (p = 0.024). The relative risk calculated in patients with a wound infection was 3.76. Lumbar spine fat thickness was on average 11.9 mm greater than patients not experiencing metal work failure.

CONCLUSIONS

This study has identified two factors associated with increased rates of metal work failure: Post-operative wound infection and lumbar spine fat thickness. When assessing surgical candidates these factors may be incorporated into surgical planning.

A radiological study of the natural history of diffuse idiopathic skeletal hyperostosis (DISH): a story of incomplete fusion

Introduction: DISH is an ankylosing disease, when fractured can be challenging to manage. A retrospective radiological study was conducted to evaluate the natural history and radiological characteristics of DISH on Computed tomography (CT).Methods: Paired CT scans with DISH that are separated at least two years apart were used to perform the following radiological measurements: Degree of disc space fusion, Osteophyte and vertebral body linear attenuation coefficients (LAC), and Osteophyte axial area size and location.Results: 164 patients were analysed with a mean duration of 4.49 years between scans. 38.14% (442/1159) of disc spaces had at least partial calcification. Most osteophytes were right sided before becoming more circumferential over time. The average fusion score was 54.17. Most of the changes in fusion occurred in the upper and lower thoracic regions. The thoracic region when compared to the lumbar region had a greater proportion of its disc spaced being fully fused. Disc level osteophyte areas were larger than Body level osteophytes. Disc osteophytes size growth rate drops over time from 10.89mm²/year in Stage 1 to 3.56mm²/year in Stage 3. Stage 3 disc spaces (-11.01HU/year) was also found to have had a reduction in their LAC over time when compared to Stage 1 disc spaces (17.04HU/year). This change in osteophyte LAC was not mirrored in the change in vertebral body LAC. We predict that the age of onset and complete thoracolumbar ankylosis of DISH to be 17.96 years and 100.59 years, respectively.Conclusion: DISH ankylosis of the spine a slow process that starts in the mid to lower thoracic region before extending cranially and caudally. After the bridging osteophyte has fully formed, remodelling of the osteophyte occurs.

Multicenter experience with andexanet alfa for refractory pericardial bleeding during catheter ablation of atrial fibrillation

INTRODUCTION

Pericardial bleeding is a rare but life-threatening complication of atrial fibrillation (AF) ablation. Patients taking uninterrupted oral anticoagulation (AC) may be at increased risk for refractory bleeding despite pericardiocentesis and administration of protamine. In such cases, andexanet alfa can be given to reverse rivaroxaban or apixaban. In this study, we aim to describe the rate of acute hemostasis and thromboembolic complications with andexanet for refractory pericardial bleeding during AF ablation.

METHODS AND RESULTS

In this multicenter, case series, participating centers identified patients who received a dose of apixaban or rivaroxaban within 24 h of AF ablation, developed refractory pericardial bleeding during the procedure despite pericardiocentesis and administration of protamine and received andexanet. Eleven patients met inclusion criteria, with mean age of 73.5 ± 5.3 years and median CHA₂ DS₂ -VASc score 4 [3-5]. All patients received protamine and pericardiocentesis, and 9 (82%) received blood products. All patients received a bolus of andexanet followed, in all but one, by a 2-h infusion. Acute hemostasis was achieved in eight patients (73%) while three required emergent surgery. One patient (9%) experienced acute ST-elevation myocardial infarction after receiving andexanet. Therapeutic AC was restarted after a mean of 2.2 ± 1.9 days and oral AC was restarted after a mean of 2.9 ± 1.6 days, with no recurrent bleeding.

CONCLUSION

In patients on uninterrupted apixaban or rivaroxaban, who develop refractory pericardial bleeding during AF ablation, andexanet can achieve hemostasis thereby avoiding the need for emergent surgery. However, there is a risk of thromboembolism following administration.

Evaluating temperature gradients across the posterior left atrium with radiofrequency ablation

INTRODUCTION

Esophageal injury is a well-known complication associated with catheter ablation. Though novel methods to mitigate esophageal injury have been developed, few studies have evaluated temperature gradients with catheter ablation across the posterior wall of the left atrium, interstitium, and esophagus.

METHODS

To investigate temperature gradients across the tissue, we developed a porcine heart-esophageal model to perform ex vivo catheter ablation on the posterior wall of the left atrium (LA), with juxtaposed interstitial tissue and esophagus. Circulating saline (5 L/min) was used to mimic blood flow along the LA and alteration of ionic content to modulate impedance. Thermistors along the region of interest were used to analyze temperature gradients. Varying time and power, radiofrequency (RF) ablation lesions were applied with an externally irrigated ablation catheter. Ablation strategies were divided into standard approaches (SAs, 10-15 g, 25-35 W, 30 s) or high-power short duration (HPSD, 10-15 g, 40-50 W, 10 s). Temperature gradients, time to the maximum measured temperature, and the relationship between measured temperature as a function of distance from the site of ablation was analyzed.

RESULTS

In total, five experiments were conducted each utilizing new porcine posterior LA wall-esophageal specimens for RF ablation (n = 60 lesions each for SA and HPSD). For both SA and HPSD, maximum temperature rise from baseline was markedly higher at the anterior wall (AW) of the esophagus compared to the esophageal lumen (SA: 4.29°C vs. 0.41°C, p < .0001 and HPSD: 3.13°C vs. 0.28°C, p < .0001). Across ablation strategies, the average temperature rise at the AW of the esophagus was significantly higher with SA relative to HPSD ablation (4.29°C vs. 3.13°C, p = .01). From the start of ablation, the average time to reach a maximum temperature as measured at the AW of the esophagus with SA was 36.49 ±  12.12 s, compared to 16.57 ±  4.54 s with HPSD ablation, p < .0001. Fit to a linear scale, a 0.37°C drop in temperature was seen for every 1 cm increase in distance from the site of ablation and thermistor location at the AW of the esophagus.

CONCLUSION

Both SA and HPSD ablation strategies resulted in markedly higher temperatures measured at the AW of the esophagus compared to the esophageal lumen, raising concern about the value of clinical intraluminal temperature monitoring. The temperature rise at the AW was lower with HPSD. A significant time delay was seen to reach the maximum measured temperature and a modest increase in distance between the site of ablation and thermistor location impacted the accuracy of monitored temperatures.

The arithmetic topology of genetic alignments

We propose a novel mathematical paradigm for the study of genetic variation in sequence alignments. This framework originates from extending the notion of pairwise relations, upon which current analysis is based on, to k-ary dissimilarity. This dissimilarity naturally leads to a generalization of simplicial complexes by endowing simplices with weights, compatible with the boundary operator. We introduce the notion of k-stances and dissimilarity complex, the former encapsulating arithmetic as well as topological structure expressing these k-ary relations. We study basic mathematical properties of dissimilarity complexes and show how this approach captures watershed moments of viral dynamics in the context of SARS-CoV-2 and H1N1 flu genomic data.

Association of Residual Ischemic Disease With Clinical Outcomes After Percutaneous Coronary Intervention

BACKGROUND

Anatomical scoring systems have been used to assess completeness of revascularization but are challenging to apply to large real-world datasets.

OBJECTIVES

The aim of this study was to assess the prevalence of complete revascularization and its association with longitudinal clinical outcomes in the U.S. Department of Veterans Affairs (VA) health care system using an automatically computed anatomic complexity score.

METHODS

Patients undergoing percutaneous coronary intervention (PCI) between October 1, 2007, and September 30, 2020, were identified, and the burden of prerevascularization and postrevascularization ischemic disease was quantified using the VA SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery) score. The association between residual VA SYNTAX score and long-term major adverse cardiovascular events (MACE; death, myocardial infarction, repeat revascularization, and stroke) was assessed.

RESULTS

A total of 57,476 veterans underwent PCI during the study period. After adjustment, the highest tertile of residual VA SYNTAX score was associated with increased hazard of MACE (HR: 2.06; 95% CI: 1.98-2.15) and death (HR: 1.50; 95% CI: 1.41-1.59) at 3 years compared to complete revascularization (residual VA SYNTAX score = 0). Hazard of 1- and 3-year MACE increased as a function of residual disease, regardless of baseline disease severity or initial presentation with acute or chronic coronary syndrome.

CONCLUSIONS

Residual ischemic disease was strongly associated with long-term clinical outcomes in a contemporary national cohort of PCI patients. Automatically computed anatomic complexity scores can be used to assess the longitudinal risk for residual ischemic disease after PCI and may be implemented to improve interventional quality.

Qualitative Evaluation of an Artificial Intelligence–Based Clinical Decision Support System to Guide Rhythm Management of Atrial Fibrillation: Survey Study

Background

Despite the numerous studies evaluating various rhythm control strategies for atrial fibrillation (AF), determination of the optimal strategy in a single patient is often based on trial and error, with no one-size-fits-all approach based on international guidelines/recommendations. The decision, therefore, remains personal and lends itself well to help from a clinical decision support system, specifically one guided by artificial intelligence (AI). QRhythm utilizes a 2-stage machine learning (ML) model to identify the optimal rhythm management strategy in a given patient based on a set of clinical factors, in which the model first uses supervised learning to predict the actions of an expert clinician and identifies the best strategy through reinforcement learning to obtain the best clinical outcome—a composite of symptomatic recurrence, hospitalization, and stroke.

Objective

We qualitatively evaluated a novel, AI-based, clinical decision support system (CDSS) for AF rhythm management, called QRhythm, which uses both supervised and reinforcement learning to recommend either a rate control or one of 3 types of rhythm control strategies—external cardioversion, antiarrhythmic medication, or ablation—based on individual patient characteristics.

Methods

Thirty-three clinicians, including cardiology attendings and fellows and internal medicine attendings and residents, performed an assessment of QRhythm, followed by a survey to assess relative comfort with automated CDSS in rhythm management and to examine areas for future development.

Results

The 33 providers were surveyed with training levels ranging from resident to fellow to attending. Of the characteristics of the app surveyed, safety was most important to providers, with an average importance rating of 4.7 out of 5 (SD 0.72). This priority was followed by clinical integrity (a desire for the advice provided to make clinical sense; importance rating 4.5, SD 0.9), backward interpretability (transparency in the population used to create the algorithm; importance rating 4.3, SD 0.65), transparency of the algorithm (reasoning underlying the decisions made; importance rating 4.3, SD 0.88), and provider autonomy (the ability to challenge the decisions made by the model; importance rating 3.85, SD 0.83). Providers who used the app ranked the integrity of recommendations as their highest concern with ongoing clinical use of the model, followed by efficacy of the application and patient data security. Trust in the app varied; 1 (17%) provider responded that they somewhat disagreed with the statement, “I trust the recommendations provided by the QRhythm app,” 2 (33%) providers responded with neutrality to the statement, and 3 (50%) somewhat agreed with the statement.

Conclusions

Safety of ML applications was the highest priority of the providers surveyed, and trust of such models remains varied. Widespread clinical acceptance of ML in health care is dependent on how much providers trust the algorithms. Building this trust involves ensuring transparency and interpretability of the model.

Prevention and Management of Hypertriglyceridemia-Induced Acute Pancreatitis During Pregnancy: A Systematic Review

Severe gestational hypertriglyceridemia can lead to acute pancreatitis, with maternal mortality rate of approximately 20%. The recent National Lipid Association part 2 expert panel recommendations provide guidance on monitoring pregnant women at high risk for hyperlipidemia. We suggest that high-risk women have triglyceride levels checked once every trimester. Fasting triglycerides >250 mg/dL should prompt monthly triglyceride levels, screening for gestational diabetes, and implementing a strict low-carbohydrate, low-fat diet, exercise. Fasting triglycerides >500 mg/dL, despite a strict dietary and lifestyle modifications, should prompt treatment with omega-3-fatty acids and continue a fat-restricted diet (<20 g total fat/d or <15% total calories) under the guidance of a registered dietician. The use of fibrates should be considered as a second-line therapy due to their unclear risk versus benefit and potential teratogenic effects. Plasmapheresis should be considered early in asymptomatic pregnant women with fasting triglyceride levels >1000 mg/dL or in pregnant women with clinical signs and symptoms of pancreatitis and triglyceride levels >500 mg/dL despite maximal lifestyle changes and pharmacologic therapy.

Limitations of Unipolar Signals in Guiding Successful Outflow Tract Premature Ventricular Contraction Ablation

OBJECTIVES

The authors sought to compare bipolar electrograms (BiEGMs) vs unipolar electrograms (UniEGMs) in guiding successful ablation of right ventricular outflow tract (RVOT) vs intramural outflow tract (OT) premature ventricular contractions (PVCs). The authors hypothesized that: 1) earliest bipolar local activation time (LAT_Bi) would better guide mapping and ablation, vs UniEGM dV/dt (LAT_Uni) or QS morphology; and 2) LAT differences using bipolar vs unipolar EGMs (ΔLAT_Bi-Uni) would be greater for intramural OT than RVOT PVCs.

BACKGROUND

UniEGMs are commonly used to annotate earliest local activation of focal arrhythmias. However, their utility in guiding PVC ablation may be limited when the PVC source is less superficial.

METHODS

Consecutive patients undergoing successful PVC ablation 2017 to2020 requiring only RVOT or RVOT+left ventricular OT (RVOT+LVOT) ablation were retrospectively analyzed. BiEGMs and UniEGMs at successful ablation sites were compared.

RESULTS

Of 70 patients, 50 required RVOT-only, and 20 required RVOT+LVOT ablation for acute and long-term PVC suppression. Mean ΔLAT_Bi-Uni was lower for RVOT vs RVOT+LVOT groups (9.3 ± 6.4 ms vs 17.4 ± 9.9 ms; P < 0.01). QS UniEGM was seen in 78% of RVOT, compared with 53% of RVOT+LVOT patients (P < 0.016). RVOT+LVOT sites most frequently included the posteroseptal RVOT and adjacent LVOT (73%), and 43% lacked a QS unipolar EGM. ΔLAT_Bi-Uni ≥15 ms best distinguished sites in which RVOT-only vs RVOT+LVOT ablation achieved acute PVC suppression (area under the curve: 0.77).

CONCLUSIONS

Earliest BiEGM activation guides successful ablation of OT PVCs better than UniEGM-guided analysis, especially when an intramural PVC source is present.

Phylogeography of the veined squid, Loligo forbesii, in European waters

The veined squid, Loligo forbesii Steenstrup, 1856, occurs at the European Shelf areas including the Azores and represents a valuable resource for the European commercial fishery in the North East Atlantic. However, very little is known about its population structure and phylogeography. This lack of knowledge also impedes the development of sustainable fishery management for this species. The present study combined the use of two types of markers that retrieve patterns of gene flow in different time spans; the analysis of 16 nuclear microsatellites and sequencing of the mitochondrial cytochrome oxidase subunit I (COI). Whereas the high mutation rate of microsatellites allows the description of recent patterns of connectivity in species, the lower mutation rate of COI provides phylogeographic patterns on a longer timescale. A total of 347 individuals of L. forbesii were investigated from nearly the entire distribution range of the species, including the North East Atlantic Shelf, the Azores and the Mediterranean. Individuals from the Western and Eastern Mediterranean Sea have never been included in a genetic study before. We were able to analyse COI sequences from all 12 sampling areas and define three clades of L. forbesii. Due to our large sampling area, we are presenting 13 COI-haplotypes that were previously unknown. The microsatellite analysis does not include the Azores but three main clades could be identified at the remaining 11 sampling sites. Low F_ST values indicate gene flow over large geographical distances. However, the genetically significant differences and an additional slight grouping in the microsatellite structure reveal that geographical barriers seem to influence the population structure and reduce gene flow. Furthermore, both markers provide strong evidence that the observed phylogeographic pattern reflects the geographical history of the Azores and the Mediterranean Sea.

The morbidity of out-of-hours surgery for Cauda Equina Syndrome

BACKGROUND

There is no literature specifically addressing the morbidity of out of hours surgery for Cauda Equina Syndrome (CES). Our paper rectifies this omission. This will assist the surgeon with real-time decision making with regards to timing of intervention in this rare but potentially disabling disease.

METHODS

A retrospective case series analysis. Individual cases were identified using local electronic theatre management systems in the four neurosurgical centres in Scotland in 2017. "Out of hours" surgery was defined as starting outside the times 0900-1700 Monday to Friday.

RESULTS

86 patients underwent out of hours surgery for CES in Scotland in 2017. One patient sustained a nerve root injury without new deficit, giving an overall risk of 1.2%. Four patients had the intra-operative complication of CSF leak, giving an overall risk of 4.7%. Five patients underwent early revision surgery, equivalent to a re-operation risk of 5.8%.

CONCLUSIONS

The morbidity of out of hours surgery for CES is comparable to that of elective microdiscectomy. Operating out of hours for CES does not appear to have an increased risk of complications. Since increased surgical risk is not borne out by our study, this should not be used as a justification to delay operative treatment.

Electrophysiologic Implications of Transcatheter Aortic Valve Replacement: Incidence, Outcomes, and Current Management Strategies

PURPOSE OF REVIEW

Transcatheter aortic valve replacement (TAVR) has changed the paradigm for management of severe aortic stenosis. Despite substantial procedural advancements, conduction system abnormalities remain a common complication following TAVR. In this review, we describe (1) incidence and risk factors for the development of conduction disturbances following TAVR, along with their prognostic significance, (2) the incidence and prognostic significance of new-onset arrhythmias following TAVR, (3) approach to management of perioperative and post-procedural conduction disturbances and arrhythmias, and (4) novel areas of research.

RECENT FINDINGS

Conduction disturbances including left bundle branch block (LBBB) and high-grade atrioventricular block (HAVB) remain common issues post-TAVR despite advancements in valve technology and improvements in procedural technique. Despite data showing most conduction abnormalities resolve over time, rates of post-procedural permanent pacemaker implantation remain high. Similarly, rates of new-onset or newly detected arrhythmia, particularly atrial fibrillation, have been widely reported post-implantation of all types of TAVR valves. Recent consensus statements and decision pathway documents have been helpful in standardizing an approach to post-TAVR conduction disturbances. New areas of research show promise both for predicting which patients will develop conduction disturbances post-TAVR and for management of HAVB with novel pacing techniques. On the other hand, management of new-onset or newly detected atrial fibrillation after TAVR remains a significant challenge without standardized treatment strategy.

Neurosurgery in octogenarians during the COVID-19 pandemic: Results from a tertiary care trauma centre

Background

In 2020, 6% of Scotland's adult population was ≥80 years. Advancements in care mean improved chances of survival at 6-months for older adults following injury to the brain or spine. The Covid-19 pandemic also resulted in local and national policies aimed at protecting the elderly. We sought to evaluate referral patterns and outcomes for patients ≥80 years referred to our institution during this period.

Objective

To evaluate referral patterns and outcomes for patients ≥80 years referred to our institution both before and during the coronavirus pandemic.

Design

Retrospective observational cohort study.

Setting

Tertiary care in a developing major trauma centre (Queen Elizabeth University Hospital, Glasgow).

Participants

All patients ≥80 years referred to the on-call neurosurgical service over two four-month periods before (2016–17; n = 1573) and after the onset of Covid-19 (2020; n = 2014).

Methods

Data on demographics, ASA, diagnosis and referral decision were collected. 30-day and 6-month mortality and functional independence were assessed.

Results

246 (before) and 335 (during Covid-19) referred patients were ≥80 years. No gender bias. A significant increase (17%) in acute trauma was seen during the pandemic months. Fewer older adults were transferred (6% to 2% Covid-19) for specialist care, most commonly for chronic subdural haematoma. Most were alive, home and independent at 6 months (47% pre and 63% during Covid-19).

Conclusions

Octogenarians feature disproportionately in acute adult neurosurgical referrals. In our department, local and national responses to the Covid-19 pandemic did not appear to influence this. Robust evidence of neurosurgical outcomes in the older adult is required to fairly distribute resources for our ageing population, but decisions must not be based on age alone.

Fractional flow reserve derived from computed tomography coronary angiography in the assessment and management of stable chest pain: the FORECAST randomized trial

Aims 

Fractional flow reserve (FFR_CT) using computed tomography coronary angiography (CTCA) determines both the presence of coronary artery disease and vessel-specific ischaemia. We tested whether an evaluation strategy based on FFR_CT would improve economic and clinical outcomes compared with standard care.

Methods and results 

Overall, 1400 patients with stable chest pain in 11 centres were randomized to initial testing with CTCA with selective FFR_CT (experimental group) or standard clinical care pathways (standard group). The primary endpoint was total cardiac costs at 9 months. Secondary endpoints were angina status, quality of life, major adverse cardiac and cerebrovascular events, and use of invasive coronary angiography. Randomized groups were similar at baseline. Most patients had an initial CTCA: 439 (63%) in the standard group vs. 674 (96%) in the experimental group, 254 of whom (38%) underwent FFR_CT. Mean total cardiac costs were higher by £114 (+8%) in the experimental group, with a 95% confidence interval from −£112 (−8%) to +£337 (+23%), though the difference was not significant (P = 0.10). Major adverse cardiac and cerebrovascular events did not differ significantly (10.2% in the experimental group vs. 10.6% in the standard group) and angina and quality of life improved to a similar degree over follow-up in both randomized groups. Invasive angiography was reduced significantly in the experimental group (19% vs. 25%, P = 0.01).

Conclusion 

A strategy of CTCA with selective FFR_CT in patients with stable angina did not differ significantly from standard clinical care pathways in cost or clinical outcomes, but did reduce the use of invasive coronary angiography.

OP0274-PARE EVALUATION OF PATIENT SATISFACTION FOR TELEHEALTH (PHONE AND VIDEO) IN RHEUMATOLOGY OUTPATIENTS DURING COVID-19 PANDEMIC

Background:

Telehealth via phone (TPhone) or video conference (TVideo) in rheumatology has been a topic of interest for many years. Its use was rapidly expanded due to the international public health emergency of coronavirus disease-19 (COVID-19) outbreak in 2020. Australian Medicare Benefits Schedule (MBS) swiftly enabled temporary MBS telehealth items on 13 March 2020, currently extended until 31 March 20211. In the early phase of the COVID-19 pandemic, Antony et al. conducted a single-centre public survey to assess patient perception of rheumatology telehealth. Their results showed that 98.4% of patients consider telehealth acceptable during the pandemic2. It is unclear, however, whether this positive perception persists after patients experience a telehealth. In addition, a survey data in 2019 suggested more than half of Australian rheumatologists work in private practice3. Therefore, inclusion of private patients will better represent patient perception of telehealth.

Objectives:

The aim of this study was to evaluate patient satisfaction with telehealth during the COVID-19 pandemic. This would determine its feasibility to be integrated in future rheumatology outpatient model.

Methods:

A questionnaire containing 30 questions was sent to rheumatology patients who attended telehealth appointments at a level 2 public hospital and a local private clinic between April and May 2020. The questionnaires aimed to obtain information on baseline demographics (sex, age, public or private patient, employment status, visual or auditory impairment), appointment details (TPhone or TVideo, usual arrangement for face-to-face (F2F) appointment, cost effectiveness) and appointment satisfaction using a 5-point Likert scale. Descriptive statistical analysis was conducted.

Results:

The questionnaire was sent to 1452 patients, of which 494 patients responded (34%). Female predominance (77.1%) and a higher proportion of TPhone (79.1%) was seen in the respondents. A majority of patients were existing patients known to the services (90.9%). More than 70% of responses indicated overall satisfaction in specialist care via telehealth, and 88.7% perceived this suitable during a pandemic. Of all respondents, 21.7% were prescribed new medication, and the majority of these patients were confident in taking the new medication after the telehealth appointment. Future acceptability for TPhone was significantly lower in private patients compared to public patients (p= 0.01). Subgroup analysis revealed that higher telehealth satisfaction was associated with needing to take time off work to attend face-to-face appointment (p= 0.02), perception of cost effectiveness (p<0.001) and TVideo (p=0.03).

Conclusion:

This is the first study which included both public and private rheumatology patients to evaluate patient satisfaction for telehealth during the COVID-19 pandemic. Overall high level of satisfaction was seen in telehealth most notably associated with its cost effectiveness. A higher percentage of patients who had TVideo compared to TPhone were receptive to future telehealth via TVideo, supportive of the importance of visual cues. This in turn will have significant administrative and technological burdens to coordinate in comparison to a F2F or TPhone review. This qualitative study provides valuable insight of patient perception of telehealth, which has the potential to compliment the traditional rheumatology outpatient model of care following the pandemic.

References:

[1]COVID-19 Temporary MBS Telehealth Services 2020 [Available from: http://www.mbsonline.gov.au/internet/mbsonline/publishing.nsf/Content/Factsheet-TempBB.

[2]Antony A, Connelly K, De Silva T, Eades L, Tillett W, Ayoub S, et al. Perspectives of Patients With Rheumatic Diseases in the Early Phase of COVID-19. Arthritis Care & Research. 2020;72(9):1189-95.

[3]Association AR. Workforce Survey Exective Summary 2019 2019 [Available from: https://rheumatology.org.au/members/documents/WorkforceSurveyExecutiveSummary-websiteMay2019.pdf.

Acknowledgements:

University of Queensland

Nursing staff at Redcliffe Hospital and Administration officers at Redcliffe & Northside Rheumatology

Disclosure of Interests:

None declared

Utility of Intracardiac Echocardiography for Guiding Ablation of Ventricular Tachycardia in Nonischemic Cardiomyopathy

Intracardiac echocardiography (ICE) is a valuable tool in cardiac ablation procedures, especially in ablation of ventricular arrhythmias. The article details how ICE can aid in ablation of ventricular arrhythmias in nonischemic cardiomyopathy.

Prioritizing allocation of COVID-19 vaccines based on social contacts increases vaccination effectiveness

We study allocation of COVID-19 vaccines to individuals based on the structural properties of their underlying social contact network. Even optimistic estimates suggest that most countries will likely take 6 to 24 months to vaccinate their citizens. These time estimates and the emergence of new viral strains urge us to find quick and effective ways to allocate the vaccines and contain the pandemic. While current approaches use combinations of age-based and occupation-based prioritizations, our strategy marks a departure from such largely aggregate vaccine allocation strategies. We propose a novel approach motivated by recent advances in (i) science of real-world networks that point to efficacy of certain vaccination strategies and (ii) digital technologies that improve our ability to estimate some of these structural properties. Using a realistic representation of a social contact network for the Commonwealth of Virginia, combined with accurate surveillance data on spatiotemporal cases and currently accepted models of within- and between-host disease dynamics, we study how a limited number of vaccine doses can be strategically distributed to individuals to reduce the overall burden of the pandemic. We show that allocation of vaccines based on individuals' degree (number of social contacts) and total social proximity time is significantly more effective than the currently used age-based allocation strategy in terms of number of infections, hospitalizations and deaths. Our results suggest that in just two months, by March 31, 2021, compared to age-based allocation, the proposed degree-based strategy can result in reducing an additional 56-110k infections, 3.2- 5.4k hospitalizations, and 700-900 deaths just in the Commonwealth of Virginia. Extrapolating these results for the entire US, this strategy can lead to 3-6 million fewer infections, 181-306k fewer hospitalizations, and 51-62k fewer deaths compared to age-based allocation. The overall strategy is robust even: (i) if the social contacts are not estimated correctly; (ii) if the vaccine efficacy is lower than expected or only a single dose is given; (iii) if there is a delay in vaccine production and deployment; and (iv) whether or not non-pharmaceutical interventions continue as vaccines are deployed. For reasons of implementability, we have used degree, which is a simple structural measure and can be easily estimated using several methods, including the digital technology available today. These results are significant, especially for resource-poor countries, where vaccines are less available, have lower efficacy, and are more slowly distributed.

Multiscale Feedback Loops in SARS-CoV-2 Viral Evolution

COVID-19 is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The viral genome is considered to be relatively stable and the mutations that have been observed and reported thus far are mainly focused on the coding region. This article provides evidence that macrolevel pandemic dynamics, such as social distancing, modulate the genomic evolution of SARS-CoV-2. This view complements the prevalent paradigm that microlevel observables control macrolevel parameters such as death rates and infection patterns. First, we observe differences in mutational signals for geospatially separated populations such as the prevalence of A23404G in CA versus NY and WA. We show that the feedback between macrolevel dynamics and the viral population can be captured employing a transfer entropy framework. Second, we observe complex interactions within mutational clades. Namely, when C14408T first appeared in the viral population, the frequency of A23404G spiked in the subsequent week. Third, we identify a noncoding mutation, G29540A, within the segment between the coding gene of the N protein and the ORF10 gene, which is largely confined to NY (>95%). These observations indicate that macrolevel sociobehavioral measures have an impact on the viral genomics and may be useful for the dashboard-like tracking of its evolution. Finally, despite the fact that SARS-CoV-2 is a genetically robust organism, our findings suggest that we are dealing with a high degree of adaptability. Owing to its ample spread, mutations of unusual form are observed and a high complexity of mutational interaction is exhibited.

A dual compression system: preliminary clinical insights from the US

There is growing evidence on an interconnection between the venous and lymphatic systems in venous leg ulceration, and the possible effects of prolonged oedema and lymphatic impairment in delayed wound healing. Compression therapy is a widely accepted treatment for venous and lymphatic disorders, as it decreases recurrence rates and prolongs the interval between recurrences. Compression bandages improve venous return, increase the volume and rate of venous flow, reduce oedema and stimulate anti-inflammatory processes. The pressure at the interface (IP) of the bandage and the skin is related to the elastic recoil of the product used and its resistance to expansion. The pressure difference between the IP in the supine and standing positions is called the static stiffness index (SSI). Elastic materials provide little resistance to muscle expansion during physical activity, resulting in small pressure differences between resting and activity, with an SSI <10mmHg. Stiff, inelastic materials with a stretch of <100% resist the increase of muscle volume during physical activity, producing higher peak pressures, an SSI of >10mmHg and a greater haemodynamic benefit than elastic systems. UrgoK2 is a novel dual-layer high-compression system consisting of an inelastic (short stretch) and elastic (long stretch) bandage, resulting in sustained tolerable resting pressure and elevated working pressures over extended wear times. It is indicated for the treatment of active venous leg ulcers and the reduction of chronic venous oedema. Each bandage layer has a visual aid to enable application at the correct pressure level. Published European studies have assessed this compression system, exploring its consistency of application, tolerability and efficacy. This article presents the first reports of health professionals' clinical experience of using the compression system in the US, where it has been recently launched. Initial feedback is promising.

Infection and Inflammation in the Wound Environment: Addressing Issues of Delayed Wound Healing With Advanced Wound Dressings

Impaired wound healing is estimated to affect about 2% of the US population, and a major goal of health care providers (HCPs) is to better understand delayed healing so they can effectively choose advanced wound dressings to manage these wounds. However, there are estimated to be more than 3000 dressing options available, making dressing selection an overwhelming burden. An expert panel of 7 HCPs experienced in diverse medical disciplines and 3 scientists convened to discuss the use of 2 families of dressings (silver-oxysalt [AgOx] dressings and oxidized regenerated cellulose/collagen [ORC/C] dressings) and delayed wound healing. Before the meeting, panelists reviewed 16 articles concerning the dressings, and 2 scientists presented on the topics of infection and inflammation in the wound environment, along with providing information about the dressing families, during the meeting. In addition, each HCP presented specific cases in which they had applied AgOx or ORC/C dressings and described how the dressing was used to manage stalled healing. After the meeting, the panelists and another HCP who was unable to attend the panel meeting provided insight and feedback for this publication, which provides an overview of the meeting. A major theme of this panel discussion was the need for a fundamental change in how HCPs approach wound care, especially for nonhealing wounds and underlying issues of infection and inflammation in the wound environment. Ultimately, the panel developed a decision-tree model for risk-stratifying patients based on their potential to have or develop these 2 underlying issues, followed by deciding on treatment options based on the status of infection and inflammation in the wound.

Genetic robustness of let-7 miRNA sequence-structure pairs

Genetic robustness, the preservation of evolved phenotypes against genotypic mutations, is one of the central concepts in evolution. In recent years a large body of work has focused on the origins, mechanisms, and consequences of robustness in a wide range of biological systems. In particular, research on ncRNAs studied the ability of sequences to maintain folded structures against single-point mutations. In these studies, the structure is merely a reference. However, recent work revealed evidence that structure itself contributes to the genetic robustness of ncRNAs. We follow this line of thought and consider sequence-structure pairs as the unit of evolution and introduce the spectrum of extended mutational robustness (EMR spectrum) as a measurement of genetic robustness. Our analysis of the miRNA let-7 family captures key features of structure-modulated evolution and facilitates the study of robustness against multiple-point mutations.

New evidence-based A1, A2, A3 alarm time zones for transferring thrombolysed patients to hyper-acute stroke units: faster is better

OBJECTIVES

The National Institute of Health and Clinical Excellence and The Royal College of Physicians recommend transferring thrombolysed patients with stroke to a hyperacute stroke unit (HASU) within 4 h from hospital arrival (T_Arrival-HASU), but there is paucity of evidence to support this cut-off. We assessed if a shorter interval within this target threshold conferred a significant improvement in patient mortality.

DESIGN

We conducted a retrospective analysis of prospectively collected data from the Sentinel Stroke National Audit Programme.

SETTING

Four major UK hyperacute stroke centres between 2014 and 2016.

PARTICIPANTS

A total of 183 men (median age = 75 years, IQR = 66-83) and 169 women (median age = 81 years, IQR = 72.5-88) admitted with acute ischaemic stroke.

MAIN OUTCOME MEASURES

We evaluated T_Arrival-HASU in relation to inpatient mortality, adjusted for age, sex, co-morbidities, stroke severity, time between procedures, time and day on arrival.

RESULTS

There were 51 (14.5%) inpatient deaths. On ROC analysis, the AUC (area under the curve) was 61.1% (52.9-69.4%, p = 0.01) and the cut-off of T_Arrival-HASU where sensitivity equalled specificity was 2 h/15 min (intermediate range = 30 min to 3 h/15 min) for predicting mortality. On logistic regression, compared with the fastest T_Arrival-HASU group within 2 h/15 min, the slowest T_Arrival-HASU group beyond upper limit of intermediate range (≥ 3 h/15 min) had an increased risk of mortality: 5.6% vs. 19.6%, adjusted OR = 5.6 (95%CI:1.5-20.6, p = 0.010).

CONCLUSIONS

We propose three new alarm time zones (A1, A2 and A3) to improve stroke survival: "A1 Zone" (T_Arrival-HASU < 2 h/15 min) indicates that a desirable target, "A2 Zone" (T_Arrival-HASU = 2 h/15 min to 3 h/15 min), indicates increasing risk and should not delay any further, and "A3 Zone" (T_Arrival-HASU ≥ 3 h/15 min) indicates high risk and should be avoided.

Use of mechanically powered disposable negative pressure wound therapy: recommendations and reimbursement update

Use of ultra-portable, mechanically powered disposable negative pressure wound therapy (dNPWT) has grown as an adjunctive modality to manage wounds in outpatient care and to expedite transition of inpatients to an outpatient setting. This technology has demonstrated similar efficacy and usability for mobile outpatients when compared with electrically powered negative pressure wound therapy devices. It was designed for patients with smaller, low to moderately exudating wounds and does not require batteries or a power source. However, very few studies address best practices for using dNPWT in a variety of wound types. There is a need for comprehensive clinical recommendations to better direct clinicians and patients in using this therapy. In addition, it is critical that providers are knowledgeable about processes for obtaining reimbursement for placement of dNPWT since codes and procedures differ drastically from standard NPWT. A panel meeting of experts with a high level of experience with dNPWT in varied wound types was convened to develop clinical recommendations and summarize current US reimbursement coding guidelines for the use of dNPWT. This publication summarizes the recommendations from panel members, in addition to supporting evidence, to help guide appropriate use of dNPWT. Panel recommendations regarding optimal patient and wound selection, wound preparation, proper patient training, and use of dNPWT in various wound types are included as well as clinical techniques for dressing application, bridging under offloading devices and compression, maintaining a seal, and protecting intact skin. Processes and codes for obtaining reimbursement for dNPWT are reviewed by care setting. Clinical recommendations and reimbursement guidelines summarized in this publication are meant to provide direction to clinicians in using dNPWT that potentially could translate into improved clinical and economic value.