Preventive percutaneous coronary intervention versus optimal medical therapy alone for the treatment of vulnerable atherosclerotic coronary plaques (PREVENT): a multicentre, open-label, randomised controlled trial

BACKGROUND

Acute coronary syndrome and sudden cardiac death are often caused by rupture and thrombosis of lipid-rich atherosclerotic coronary plaques (known as vulnerable plaques), many of which are non-flow-limiting. The safety and effectiveness of focal preventive therapy with percutaneous coronary intervention of vulnerable plaques in reducing adverse cardiac events are unknown. We aimed to assess whether preventive percutaneous coronary intervention of non-flow-limiting vulnerable plaques improves clinical outcomes compared with optimal medical therapy alone.

METHODS

PREVENT was a multicentre, open-label, randomised controlled trial done at 15 research hospitals in four countries (South Korea, Japan, Taiwan, and New Zealand). Patients aged 18 years or older with non-flow-limiting (fractional flow reserve >0·80) vulnerable coronary plaques identified by intracoronary imaging were randomly assigned (1:1) to either percutaneous coronary intervention plus optimal medical therapy or optimal medical therapy alone, in block sizes of 4 or 6, stratified by diabetes status and the performance of percutaneous coronary intervention in a non-study target vessel. Follow-up continued annually in all enrolled patients until the last enrolled patient reached 2 years after randomisation. The primary outcome was a composite of death from cardiac causes, target-vessel myocardial infarction, ischaemia-driven target-vessel revascularisation, or hospitalisation for unstable or progressive angina, assessed in the intention-to-treat population at 2 years. Time-to-first-event estimates were calculated with the Kaplan-Meier method and were compared with the log-rank test. This report is the principal analysis from the trial and includes all long-term analysed data. The trial is registered at ClinicalTrials.gov, NCT02316886, and is complete.

FINDINGS

Between Sept 23, 2015, and Sept 29, 2021, 5627 patients were screened for eligibility, 1606 of whom were enrolled and randomly assigned to percutaneous coronary intervention (n=803) or optimal medical therapy alone (n=803). 1177 (73%) patients were men and 429 (27%) were women. 2-year follow-up for the primary outcome assessment was completed in 1556 (97%) patients (percutaneous coronary intervention group n=780; optimal medical therapy group n=776). At 2 years, the primary outcome occurred in three (0·4%) patients in the percutaneous coronary intervention group and in 27 (3·4%) patients in the medical therapy group (absolute difference -3·0 percentage points [95% CI -4·4 to -1·8]; p=0·0003). The effect of preventive percutaneous coronary intervention was directionally consistent for each component of the primary composite outcome. Serious clinical or adverse events did not differ between the percutaneous coronary intervention group and the medical therapy group: at 2 years, four (0·5%) versus ten (1·3%) patients died (absolute difference -0·8 percentage points [95% CI -1·7 to 0·2]) and nine (1·1%) versus 13 (1·7%) patients had myocardial infarction (absolute difference -0·5 percentage points [-1·7 to 0·6]).

INTERPRETATION

In patients with non-flow-limiting vulnerable coronary plaques, preventive percutaneous coronary intervention reduced major adverse cardiac events arising from high-risk vulnerable plaques, compared with optimal medical therapy alone. Given that PREVENT is the first large trial to show the potential effect of the focal treatment for vulnerable plaques, these findings support consideration to expand indications for percutaneous coronary intervention to include non-flow-limiting, high-risk vulnerable plaques.

FUNDING

The CardioVascular Research Foundation, Abbott, Yuhan Corp, CAH-Cordis, Philips, and Infraredx, a Nipro company.

Preventive PCI or medical therapy alone for vulnerable atherosclerotic coronary plaque: Rationale and design of the randomized, controlled PREVENT trial

BACKGROUND

Acute coronary syndromes are commonly caused by the rupture of vulnerable plaque, which often appear angiographically not severe. Although pharmacologic management is considered standard therapy for stabilizing plaque vulnerability, the potential role of preventive local treatment for vulnerable plaque has not yet been determined. The PREVENT trial was designed to compare preventive percutaneous coronary intervention (PCI) plus optimal medical therapy (OMT) with OMT alone in patients with functionally nonsignificant high-risk vulnerable plaques.

METHODS

The PREVENT trial is a multinational, multicenter, prospective, open-label, active-treatment-controlled randomized trial. Eligible patients have at least 1 angiographically significant stenosis (diameter stenosis >50% by visual estimation) without functional significance (fractional flow reserve [FFR] >0.80). Target lesions are assessed by intracoronary imaging and must meet at least 2 imaging criteria for vulnerable plaque; (1) minimal lumen area <4.0 mm2; (2) plaque burden >70%; (3) maximal lipid core burden index in a 4 mm segment >315 by near infrared spectroscopy; and (4) thin cap fibroatheroma as determined by virtual histology or optical coherence tomography. Enrolled patients are randomly assigned in a 1:1 ratio to either preventive PCI with either bioabsorbable vascular scaffolds or metallic everolimus-eluting stents plus OMT or OMT alone. The primary endpoint is target-vessel failure, defined as the composite of death from cardiac causes, target-vessel myocardial infarction, ischemic-driven target-vessel revascularization, or hospitalization for unstable or progressive angina, at 2 years after randomization.

RESULTS

Enrollment of a total of 1,608 patients has been completed. Follow-up of the last enrolled patient will be completed in September 2023 and primary results are expected to be available in early 2024.

CONCLUSIONS

The PREVENT trial is the first large-scale, randomized trial to evaluate the effect of preventive PCI on non-flow-limiting vulnerable plaques containing multiple high-risk features that is appropriately powered for clinical outcomes. PREVENT will provide compelling evidence as to whether preventive PCI of vulnerable plaques plus OMT improves patient outcomes compared with OMT alone.

CLINICAL TRIAL REGISTRATION

URL: https://www.

CLINICALTRIALS

gov. Unique identifier: NCT02316886.

KEY POINTS

The PREVENT trial is the first, large-scale randomized clinical trial to evaluate the effect of preventive PCI on non-flow-limiting vulnerable plaque with high-risk features. It will provide compelling evidence to determine whether PCI of focal vulnerable plaques on top of OMT improves patient outcomes.

Emergency versus semi-elective management of mandible fractures: a Maxillofacial Trainee Research Collaborative (MTReC) study

INTRODUCTION

Recent evidence suggests that acute emergency management of mandible fractures does not improve surgical outcomes yet is associated with increased financial burden. Current NHS policy advocating for increased adoption of day-case and semi-elective surgical procedures to reduce bed strain must be balanced with providing timely, effective treatment. Our research aims to determine patient groups currently managed via semi-elective admission and whether this can be extended to other groups to provide safe and effective management of mandible fractures.

METHODS

A multi-national trainee-led audit of mandibular fractures across 49 units was completed by the Maxillofacial Trainee Research Collaborative (MTReC). Each unit prospectively collected data on fractures on admission and at follow-up. Data collected included patient demographics, behaviour, health, injury, timing to intervention and surgical complications.

RESULTS

Data were collected on 947 mandibular fractures. Of the surgically managed patients, 649 (90%) were managed via acute emergency admission at the time of presentation, while 68 (10%) were managed semi-electively. Patient demographics, injury pattern and mechanism appeared to significantly affect timing of management, whereas patient behaviour, health status, timing of injury and presentation did not. Semi-elective management was associated with a significantly shorter inpatient duration (0.9 versus 1.9 days, p=0.000) with no differences in readmission, antibiotic usage or surgical complications (p=1.000, RR 1.030).

CONCLUSION

Our study demonstrates the efficacy of planned admissions and semi-elective management of mandibular fractures. Simple mandibular fractures in compliant patients are suitable for semi-elective treatment. Holistic patient assessment and tailored surgical planning is crucial in determining admission modality to effectively manage mandibular trauma.

Sustainable management of the potato cyst nematode, Globodera rostochiensis, with two microbial fermentation products

Potato cyst nematodes (PCN) cause an overall 9% yield loss of total potato production worldwide. Research on sustainable management of PCN is still under progress. Two microbial fermentation products (MFPs) from Alltech, a proprietary blend formulated with a bacterial fermentation media and a Cu component (MFP5075), and a microbial based product (MFP3048), were evaluated against the PCN Globodera rostochiensis. In laboratory tests, effectiveness of the MFPs was recorded in terms of PCN juveniles (J2) hatching from cysts, J2 mortality and their attraction toward potato roots using pluronic gel. Greenhouse trials were conducted to study the effect of the products on PCN infestation in potato plants and a pilot scale experiment was conducted to study the impact of these MFPs on nematode biodiversity in garden soil. All treatments were performed within a concentration range of 0, 0.5, 1, and 2% (v/v) MFP5075 and 2, 6, 10, and 20 g/10 ml (w/v) MFP3048. The attraction assay, juvenile hatching and the PCN infestation in plants results were compared with those in an untreated control and a commercial nematicide (Nemguard™) treatment. After 24 h of treatment with 0.5 and 1% MFP5075, a 13-fold and 43-fold reduction, respectively, relative to J2 survival was recorded compared to that of untreated control. However, no J2 survived at 2% and above concentration of the MFP5075 treatment. Treatment with MFP3048 was effective in causing mortality of J2 only after 48-h. In the attraction assay, a 20-fold and 8-fold reduction in number of J2 attracted toward potato roots was observed, when treated with MFP5075, compared to the untreated and the Nemguard™ treatment, respectively. Subsequently, 30-35 PCN cysts were treated with both products dissolved in potato root diffusate and the results were recorded in terms of number of J2 hatched in each treatment after 10 days. No J2 hatched in the MFP5075 treatment, whereas mean numbers (±SE) of 243 ± 11.5, 30 ± 2.5, and 1.3 ± 0.6 J2 were noted in the untreated control, MFP3048, and the Nemguard™ treatment, respectively. The treatment with the MFPs compromised the integrity of the unhatched J2, which looked granular, whereas the internal organs of the unhatched J2 could be clearly identified in the untreated control. In plant infestation studies, treatment with MFP3048 and MFP5075 caused 90.6 and 84.9 percent reduction in PCN infestation, respectively, in terms of cysts developed on roots compared to untreated control. Overall, results indicate that the MFPs could potentially provide a promising alternative for sustainable PCN management.

Characterization of the Monocyte Response to Biomaterial Therapy for Cardiac Repair

Biomaterials are scaffolds designed to mimic the extracellular matrix and stimulate tissue repair. Biomaterial therapies have shown promise for improving wound healing in cardiac tissue after ischemic injury. An unintentional consequence of biomaterial delivery may be the stimulation of inflammation through recruitment of circulating monocytes into the tissue. Monocytes are a type of leukocyte (white blood cell) that play a critical role in pathogen recognition, phagocytosis of foreign material, and presentation of antigens to initiate an adaptive immune response. An increase in the pro-inflammatory subset of monocytes, marked by Ly6C antigen expression, in response to biomaterials can lead to rapid material degradation, ineffective treatment, and worsening of tissue injury. Flow cytometry is a leading method for screening the recruitment of monocytes to the heart in response to biomaterial injection. Here, we describe the isolation of leukocytes from the heart, blood, and spleen of mice treated with a biomaterial post-myocardial infarction and describe a flow cytometry protocol used to quantify the levels of major leukocyte subtypes, including Ly6C⁺ inflammatory monocytes.

Abstract MP233: Investigating Genotoxic-induced Innate Immune Pathways Leading To Heart Failure With Preserved Ejection Fraction For Developing Effective Treatments

Background: A hallmark of heart failure pathologies is excessive and cumulative DNA damage, leading to an increased and accelerated cardiac cellular senescence. We aimed to investigate the role of DNA breaks in inducing inflammation leading to adverse remodeling, premature senescence, and cardiac dysfunction leading to onset of Heart Failure with preserved Ejection Fraction (HFpEF), a specific type of disease prevalent in the aging population.

Results: We use heart-focused ionizing radiation, a novel in vivo technique to induce aging related DNA damage and onset of diastolic dysfunction and HFpEF (n= 4-5 per group & per species; animals used: Rattus norvegicus and Mus musculus). We performed functional analysis, histological tissue assessment and molecular investigations to evaluate and validate this novel animal model technique. DNA damage response is upregulated in aging-related Heart Failure, and here demonstrated in our novel heart-focused radiation technique. Using in vitro ionizing radiation exposure alters cardiomyocyte morphology and activates inflammation, leading to upregulation of fibrosis and senescence markers. Finally using experimental inhibitor compounds targeting the cGAS-STING axis of innate immunity, we show effective attenuation of this relevant pathway, leading to decreased systemic inflammation, cardiomyocyte remodeling, and senescence associated with DNA damage injury.

Conclusions: We present a novel technique to induce genotoxic outcomes and inflammation of the heart, leading to HFpEF pathology. We elucidate novel connections from the onset and accumulation of unresolved DNA damage, to activation of specialized innate immune cellular responses, and ultimately upregulation of cardiac tissue specific inflammation, fibrosis and senescence. Finally we demonstrate that antagonizing the cGAS-STING pathway could allow a precision medicine approach to treating genotoxic and inflammatory HFpEF.

Transitioning a cardiovascular health and rehabilitation programme to a virtual platform during covid 19

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

Our Hearts Our Minds

Purpose

Can a virtual cardiovascular prevention and rehabilitation programme be as effective as face-to-face programme.

Background

The Our Hearts Our Minds (OHOM) prevention and rehabilitation programme rapidly transitioned to a virtual platform in the covid era.  Here we compare if a virtual programme potentially could offer the same standard of the nursing intervention (education, smoking cessation, medical risk factor management and psychosocial health) as the previous face to face programme

Methods

Both the initial assessment (IA) and end of programme (EOP) assessments were conducted via telephone/video as per patient preference. The following measures were recorded at both time points (home blood pressure (BP) monitors were provided)

Smoking (self report) BP/Heart rate, Lipids/HbA1c (facilitated by phlebotomy hub), cardio protective drugs (doses, adherence), Hospital Anxiety and Depression score, EuroQoL

Nursing Intervention Smoking cessation counselling and pharmacotherapy where appropriate

Weekly meeting with cardiologist to optimise BP and lipid management and up titration cardio protective drugs

Bimonthly virtual coaching consultation for monitoring/goal resetting

Bimonthly group video education sessions

Results

From April to November 2020, of the 432 referrals received 400 were eligible with 377 accepting the offer of an IA (94% response rate). 262 have had an IA with the remaining 115 awaiting an assessment date.  Of the completed IA’s 257 were willing to attend the programme (98% uptake).  120 had been offered an end of programme assessment with 114 attending (96% of those offered). The results for the virtual programme were then compared to the same period one year previously when the programme was fully face to face and are outlined in the table below.

The comparison of results delivered via remote delivery are remarkably similar to those achieved in the previous year delivered via face to face.

Conclusion

Initial data has shown that virtual delivery of the nursing component of the OHOM prevention/rehabilitation programme was highly acceptable to patients and was as effective as that of the traditional face to face service.

Table 1 below exhibits the clinical and patient-reported outcomes.

The environmental impact of personal protective equipment in a pre and post COVID era in the ENT clinic

Purpose

The use of single use plastic items and plastic wrapping has increased over the last number of decades. Outside of the medical field there has been a conscious drive to reduce single use plastic and reuse items to reduce the amount of waste we produce. We undertook this investigation to quantify our plastic waste production and generate ideas to reduce this volume.

Methodology

Data was collected from a University Hospital ENT outpatient department via real-time recording methods using standard data collection forms. We measured plastic unit usage pre and post COVID restrictions and compared this to our number of patient encounters. Projections of plastic usage were determined via a hypothetical resumption of patient services model.

Results

In total there were 440 patients included. In period one the mean units of plastic used per day was 65.1 (median 67; range 27–84). In the second period, the mean number of plastic units was 23.4 (median 22; range 1–7). Blue nitrile gloves and masks were the most commonly used single use items. The hypothetical projection model predicted a 147.6% increase in single use items following the introduction of COVID precautions.

Conclusion

We have a duty of care not only to our patients but future generations of patients and the environment which we share. Single use items and excessive plastic wrapping have benefits in terms of convenience and sterility, but these conveniences can be easily extended to reusable types to limit our volume of waste, reduce our waste management costs and protect our environment.

Inner ear drug delivery through a cochlear implant: Pharmacokinetics in a Macaque experimental model

OBJECTIVES

The method of drug delivery directly into the cochlea with an implantable pump connected to a CI electrode array ensures long-term delivery and effective dose control, and also provides the possibility to use different drugs. The objective is to develop a model of inner ear pharmacokinetics of an implanted cochlea, with the delivery of FITC-Dextran, in the non-human primate model.

DESIGN

A preclinical cochlear electrode array (CI Electrode Array HL14DD, manufactured by Cochlear Ltd.) attached to an implantable peristaltic pump filled with FITC-Dextran was implanted unilaterally in a total of 15 Macaca fascicularis (Mf). Three groups were created (5 Mf in each group), according to three different drug delivery times: 2 hours, 24 hours and 7 days. Perilymph (10 samples, 1μL each) was sampled from the apex of the cochlea and measured immediately after extraction with a spectrofluorometer. After scarifying the specimens, x-Rays and histological analysis were performed.

RESULTS

Surgery, sampling and histological analysis were performed successfully in all specimens. FITC-Dextran quantification showed different patterns, depending on the delivery group. In the 2 hours injection experiment, an increase in FITC-Dextran concentrations over the sample collection time was seen, reaching maximum concentration peaks (420-964µM) between samples 5 and 7, decreasing in successive samples, without returning to baseline. The 24-hours and 7-days injection experiments showed even behaviour throughout the 10 samples obtained, reaching a plateau with mean concentrations ranging from 2144 to 2564 µM and from 1409 to 2502µM, respectively. Statistically significant differences between the 2 hours and 24 hours groups (p = 0.001) and between the 2 hours and 7 days groups (p = 0.037) were observed, while between the 24 hours and 7 days groups no statistical differences were found.

CONCLUSIONS

This experimental study shows that a model of drug delivery and pharmacokinetics using an active pump connected to an electrode array is feasible in Mf. An infusion time ranging from 2 to 24 hours is required to reach a maximum concentration peak at the apex. It establishes then an even concentration profile from base to apex that is maintained throughout the infusion time in Mf. Flow mechanisms during injection and during sampling that may explain such findings may involve cochlear aqueduct flow as well as the possible existence of substance exchange from scala tympani to extracellular spaces, such as the modiolar space or the endolymphatic sinus, acting as a substance reservoir to maintain a relatively flat concentration profile from base to apex during sampling. Leveraging the learnings achieved by experimentation in rodent models, we can move to experiment in non-human primate with the aim of achieving a useful model that provides transferrable data to human pharmacokinetics. Thus, it may broaden clinical and therapeutic approaches to inner ear diseases.

High flow oxygen and risk of mortality in patients with a suspected acute coronary syndrome: pragmatic, cluster randomised, crossover trial

OBJECTIVE

To determine the association between high flow supplementary oxygen and 30 day mortality in patients presenting with a suspected acute coronary syndrome (ACS).

DESIGN

Pragmatic, cluster randomised, crossover trial.

SETTING

Four geographical regions in New Zealand.

PARTICIPANTS

40 872 patients with suspected or confirmed ACS included in the All New Zealand Acute Coronary Syndrome Quality Improvement registry or ambulance ACS pathway during the study periods. 20 304 patients were managed using the high oxygen protocol and 20 568 were managed using the low oxygen protocol. Final diagnosis of ST elevation myocardial infarction (STEMI) and non-STEMI were determined from the registry and ICD-10 discharge codes.

INTERVENTIONS

The four geographical regions were randomly allocated to each of two oxygen protocols in six month blocks over two years. The high oxygen protocol recommended oxygen at 6-8 L/min by face mask for ischaemic symptoms or electrocardiographic changes, irrespective of the transcapillary oxygen saturation (SpO₂). The low oxygen protocol recommended oxygen only if SpO₂ was less than 90%, with a target SpO₂ of less than 95%.

MAIN OUTCOME MEASURE

30 day all cause mortality determined from linkage to administrative data.

RESULTS

Personal and clinical characteristics of patients managed under both oxygen protocols were well matched. For patients with suspected ACS, 30 day mortality for the high and low oxygen groups was 613 (3.0%) and 642 (3.1%), respectively (odds ratio 0.97, 95% confidence interval 0.86 to 1.08). For 4159 (10%) patients with STEMI, 30 day mortality for the high and low oxygen groups was 8.8% (n=178) and 10.6% (n=225), respectively (0.81, 0.66 to 1.00) and for 10 218 (25%) patients with non-STEMI was 3.6% (n=187) and 3.5% (n=176), respectively (1.05, 0.85 to 1.29).

CONCLUSION

In a large patient cohort presenting with suspected ACS, high flow oxygen was not associated with an increase or decrease in 30 day mortality.

TRIAL REGISTRATION

ANZ Clinical Trials ACTRN12616000461493.

Feminization of hawksbill turtle hatchlings in the twenty-first century at an important regional nesting aggregation

Projected climate change is forecasted to have significant effects on biological systems worldwide. Marine turtles in particular may be vulnerable, as the sex of their offspring is determined by their incubating temperature, termed temperature-dependent sex determination. This study aimed to estimate historical, and forecast future, primary sex ratios of hawksbill turtle Eretmochelys imbricata hatchlings at an important nesting ground in northeastern Qatar. Incubation temperatures from the Arabian/Persian Gulf were measured over 2 nesting seasons. Climate data from same period were regressed with nest temperatures to estimate incubation temperatures and hatchling sex ratios for the site from 1993 to 2100. Future hatchling sex ratios were estimated for 2 climate forecasts, one mid-range (SSP245) and one extreme (SSP585). Historical climate data showed female-biased sex ratios of 73.2 ± 12.1% from 1993 to 2017. Female biases from 2018 to 2100 averaged 85.7% ± 6.7% under the mid-range scenario and 87.9% ± 5.4% under the high-range scenario. In addition, predicted female hatchling production was >90% from 2054 and 2052 for SSP245 and SSP585, respectively. These results show that hawksbill primary sex ratios in Qatar are at risk of significant feminization by the year 2100 and that hawksbill turtle incubation temperatures in an extreme, understudied environment are already comparable to those predicted in tropical rookeries during the latter half of the 21st century. These results can help conservationists predict primary sex ratios for hawksbill turtles in the region in the face of 21st-century climate change.

Faunal mediated carbon export from mangroves in an arid area

The outwelling paradigm argues that mangrove and saltmarsh wetlands export much excess production to downstream marine systems. However, outwelling is difficult to quantify and currently 40-50% of fixed carbon is unaccounted for. Some carbon is thought outwelled through mobile fauna, including fish, which visit and feed on mangrove produce during tidal inundation or early life stages before moving offshore, yet this pathway for carbon outwelling has never been quantified. We studied faunal carbon outwelling in three arid mangroves, where sharp isotopic gradients across the boundary between mangroves and down-stream systems permitted spatial differentiation of source of carbon in animal tissue. Stable isotope analysis (C, N, S) revealed 22-56% of the tissue of tidally migrating fauna was mangrove derived. Estimated consumption rates showed that 1.4% (38 kg C ha^-1 yr^-1) of annual mangrove litter production was directly consumed by migratory fauna, with <1% potentially exported. We predict that the amount of faunally-outwelled carbon is likely to be highly correlated with biomass of migratory fauna. While this may vary globally, the measured migratory fauna biomass in these arid mangroves was within the range of observations for mangroves across diverse biogeographic ranges and environmental settings. Hence, this study provides a generalized prediction of the relatively weak contribution of faunal migration to carbon outwelling from mangroves and the current proposition, that the unaccounted-for 40-50% of mangrove C is exported as dissolved inorganic carbon, remains plausible.

Ketamine infusion reduces narcotic requirements following gastric bypass surgery: a randomized controlled trial

BACKGROUND

As the obesity epidemic worsens, anesthesiologists should expect to see more obese patients presenting for surgical procedures. Opioids cause respiratory depression, which has caused complications in patients with obstructive sleep apnea. Opioids can also cause nausea, prolonging the time that patients spend in the postanesthesia care unit. Ketamine is a potential analgesic alternative that may have advantages to narcotics in the bariatric population.

OBJECTIVES

To determine whether an intraoperative ketamine infusion would reduce postoperative narcotic use in patients during the first 48 hours after laparoscopic gastric bypass.

SETTING

Major academic medical center.

METHODS

There were 54 participating patients. The intervention group (n = 27) was randomized to receive 100 μg of fentanyl with anesthesia induction, then a 20-mg bolus of ketamine, followed by a 5 μg/kg/min intraoperative ketamine infusion starting after anesthesia induction and ending after wound closure commenced. The control group (narcotic only, n = 27) also received 100 μg of fentanyl at anesthesia induction and intraoperative boluses of fentanyl at the discretion of the anesthesia team, with .3 mg of hydromorphone administered approximately 45 minutes before the completion of surgery.

RESULTS

At 24 hours, the mean morphine-equivalent units (MEUs) were 12.7 (standard deviation [SD], 9.9; 95% confidence interval [CI], 8.8-16.6) for the ketamine group (n = 28) and 16.5 (SD, 9.8; 95% CI, 12.6-20.4) for the control group (n = 28). At 48 hours, the MEUs were 16.7 (SD, 12.0; 95% CI, 11.9-21.4) for the ketamine group and 22.7 (SD, 14.9; 95% CI, 16.8-28.6) for the control group. Cumulative MEUs for 24 hours (P = .039) and 48 hours (P = .058) postoperatively were lower in the ketamine group compared with the narcotic-only (control) group, although the difference at 48 hours did not reach statistical significance. Compared with the narcotic-only group, the ketamine group used 26% fewer MEUs after 24 hours and 31% fewer MEUs after 48 hours. This difference can mostly be attributed to group differences during the first 6 hours after surgery.

CONCLUSIONS

Ketamine successfully reduced the amount of opioids required to control bariatric patients' pain at 24 hours postoperatively, but not over the 48-hour postoperative period.

Innate Immune Nod1/RIP2 Signaling Is Essential for Cardiac Hypertrophy but Requires Mitochondrial Antiviral Signaling Protein for Signal Transductions and Energy Balance

BACKGROUND

Cardiac hypertrophy is a key biological response to injurious stresses such as pressure overload and, when excessive, can lead to heart failure. Innate immune activation by danger signals, through intracellular pattern recognition receptors such as nucleotide-binding oligomerization domain 1 (Nod1) and its adaptor receptor-interacting protein 2 (RIP2), might play a major role in cardiac remodeling and progression to heart failure. We hypothesize that Nod1/RIP2 are major contributors to cardiac hypertrophy, but may not be sufficient to fully express the phenotype alone.

METHODS

To elucidate the contribution of Nod1/RIP2 signaling to cardiac hypertrophy, we randomized Nod1^-/-, RIP2^-/-, or wild-type mice to transverse aortic constriction or sham operations. Cardiac hypertrophy, fibrosis, and cardiac function were examined in these mice.

RESULTS

Nod1 and RIP2 proteins were upregulated in the heart after transverse aortic constriction, and this was paralleled by increased expression of mitochondrial proteins, including mitochondrial antiviral signaling protein (MAVS). Nod1^-/- and RIP2^-/- mice subjected to transverse aortic constriction exhibited better survival, improved cardiac function, and decreased cardiac hypertrophy. Downstream signal transduction pathways that regulate inflammation and fibrosis, including NF (nuclear factor) κB and MAPK (mitogen-activated protein kinase)-GATA4/p300, were reduced in both Nod1^-/- and RIP2^-/- mice after transverse aortic constriction compared with wild-type mice. Coimmunoprecipitation of extracted cardiac proteins and confocal immunofluorescence microscopy showed that Nod1/RIP2 interaction was robust and that this complex also included MAVS as an essential component. Suppression of MAVS expression attenuated the complex formation, NF κB signaling, and myocyte hypertrophy. Interrogation of mitochondrial function compared in the presence or ablation of MAVS revealed that MAVS serves to suppress mitochondrial energy output and mediate fission/fusion related dynamic changes. The latter is possibly linked to mitophagy during cardiomyocytes stress, which may provide an intriguing link between innate immune activation and mitochondrial energy balance under stress or injury conditions.

CONCLUSIONS

We have identified that innate immune Nod1/RIP2 signaling is a major contributor to cardiac remodeling after stress. This process is critically joined by and regulated through the mitochondrial danger signal adapter MAVS. This novel complex coordinates remodeling, inflammatory response, and mitochondrial energy metabolism in stressed cardiomyocytes. Thus, Nod1/RIP2/MAVS signaling complex may represent an attractive new therapeutic approach toward heart failure.

RIPK1 gene variants associate with obesity in humans and can be therapeutically silenced to reduce obesity in mice

Obesity is a major public health burden worldwide and is characterized by chronic low-grade inflammation driven by the cooperation of the innate immune system and dysregulated metabolism in adipose tissue and other metabolic organs. Receptor-interacting serine/threonine-protein kinase 1 (RIPK1) is a central regulator of inflammatory cell function that coordinates inflammation, apoptosis and necroptosis in response to inflammatory stimuli. Here we show that genetic polymorphisms near the human RIPK1 locus associate with increased RIPK1 gene expression and obesity. We show that one of these single nucleotide polymorphisms is within a binding site for E4BP4 and increases RIPK1 promoter activity and RIPK1 gene expression in adipose tissue. Therapeutic silencing of RIPK1 in vivo in a mouse model of diet-induced obesity dramatically reduces fat mass, total body weight and improves insulin sensitivity, while simultaneously reducing macrophage and promoting invariant natural killer T cell accumulation in adipose tissue. These findings demonstrate that RIPK1 is genetically associated with obesity, and reducing RIPK1 expression is a potential therapeutic approach to target obesity and related diseases.

Publisher Correction: RIPK1 gene variants associate with obesity in humans and can be therapeutically silenced to reduce obesity in mice

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Challenges in the veterinary microbiology diagnostic laboratory: a novel Acinetobacter species as presumptive cause for feline unilateral conjunctivitis

The present study highlights challenges in the veterinary microbiology diagnostic laboratory in the identification of bacteria responsible for infections in veterinary settings, particularly when evidence-based data is lacking. A 1.8-year-old neutered male domestic cat (FIV/FeLV negative) was presented to a veterinary practice in April 2016 with a history of left unilateral mild conjunctivitis that was empirically treated with fusidic acid and chloramphenicol. In January 2017, the same animal was presented with chronic left unilateral conjunctivitis and an eye swab was submitted for microbiological culture and susceptibility testing. Significant growth was not detected in two samples tested. Finally, in February 2017 another eye swab produced a slow growing pure culture identified by VITEK 2 as Neisseria cinerea (94 % confidence). Given the morphology and multidrug resistance profile of the isolate a 16S rRNA PCR was performed for definitive identification. The nucleotide sequence of the PCR amplicon was 99 % homologous to Acinetobacter equi sp. nov. strain 114. Veterinary microbiology diagnostic laboratories play an important role worldwide, not only in preserving animal health and welfare but also in controlling the spread of zoonotic pathogens. The lack of evidence-based information on the ocular microbiome of healthy cats and the complexity of bacterial ecosystems renders the interpretation of results difficult. A further problem for both the laboratory and the clinician is the lack of interpretive criteria for antibiotic susceptibility test results for some types of infections in animals (including those caused by Acinetobacter) and the complete unavailability of criteria for topical antibiotic preparations.

The Impact of Prior Season Vaccination on Subsequent Influenza Vaccine Effectiveness to Prevent Influenza-related Hospitalizations Over 4 Influenza Seasons in Canada

BACKGROUND

Recent studies have demonstrated the possibility of negative associations between prior influenza vaccines and subsequent influenza vaccine effectiveness (VE), depending on season and strain. We investigated this association over 4 consecutive influenza seasons (2011-2012 through 2014-2015) in Canada.

METHODS

Using a matched test-negative design, laboratory-confirmed influenza cases and matched test-negative controls admitted to hospitals were enrolled. Patients were stratified into 4 groups according to influenza vaccine history (not vaccinated current and prior season [referent], vaccinated prior season only, vaccinated current season only, and vaccinated both current and prior season). Conditional logistic regression was used to estimate VE; prior vaccine impact was assessed each season for overall effect and effect stratified by age (<65 years, ≥65 years) and type/subtype (A/H1N1, A/H3N2, influenza B).

RESULTS

Overall, mainly nonsignificant associations were observed. Trends of nonsignificant decreased VE among patients repeatedly vaccinated in both prior and current season relative to the current season only were observed in the A/H3N2-dominant seasons of 2012-2013 and 2014-2015. Conversely, in 2011-2012, during which B viruses circulated, and in 2013-2014, when A/H1N1 circulated, being vaccinated in both seasons tended to result in a high VE in the current season against the dominant circulating subtype.

CONCLUSIONS

Prior vaccine impact on subsequent VE among Canadian inpatients was mainly nonsignificant. Even in circumstances where we observed a trend of negative impact, being repeatedly vaccinated was still more effective than not receiving the current season's vaccine. These findings favor continuation of annual influenza vaccination recommendations, particularly in older adults.

CLINICAL TRIALS REGISTRATION

NCT01517191.

c-Myb Exacerbates Atherosclerosis through Regulation of Protective IgM-Producing Antibody-Secreting Cells

Mechanisms that govern transcriptional regulation of inflammation in atherosclerosis remain largely unknown. Here, we identify the nuclear transcription factor c-Myb as an important mediator of atherosclerotic disease in mice. Atherosclerosis-prone animals fed a diet high in cholesterol exhibit increased levels of c-Myb in the bone marrow. Use of mice that either harbor a c-Myb hypomorphic allele or where c-Myb has been preferentially deleted in B cell lineages revealed that c-Myb potentiates atherosclerosis directly through its effects on B lymphocytes. Reduced c-Myb activity prevents the expansion of atherogenic B2 cells yet associates with increased numbers of IgM-producing antibody-secreting cells (IgM-ASCs) and elevated levels of atheroprotective oxidized low-density lipoprotein (OxLDL)-specific IgM antibodies. Transcriptional profiling revealed that c-Myb has a limited effect on B cell function but is integral in maintaining B cell progenitor populations in the bone marrow. Thus, targeted disruption of c-Myb beneficially modulates the complex biology of B cells in cardiovascular disease.

The Science Underlying COVID-19: Implications for the Cardiovascular System

The coronavirus disease 2019 (COVID-19) pandemic has affected health and economy worldwide on an unprecedented scale. Patients have diverse clinical outcomes, but those with preexisting cardiovascular disease, hypertension, and related conditions incur disproportionately worse outcome. The high infectivity of severe acute respiratory syndrome coronavirus 2 is in part related to new mutations in the receptor binding domain, and acquisition of a furin cleavage site in the S-spike protein. The continued viral shedding in the asymptomatic and presymptomatic individuals enhances its community transmission. The virus uses the angiotensin converting enzyme 2 receptor for internalization, aided by transmembrane protease serine 2 protease. The tissue localization of the receptors correlates with COVID-19 presenting symptoms and organ dysfunction. Virus-induced angiotensin converting enzyme 2 downregulation may attenuate its function, diminish its anti-inflammatory role, and heighten angiotensin II effects in the predisposed patients. Lymphopenia occurs early and is prognostic, potentially associated with reduction of the CD4+ and some CD8+ T cells. This leads to imbalance of the innate/acquired immune response, delayed viral clearance, and hyperstimulated macrophages and neutrophils. Appropriate type I interferon pathway activation is critical for virus attenuation and balanced immune response. Persistent immune activation in predisposed patients, such as elderly adults and those with cardiovascular risk, can lead to hemophagocytosis-like syndrome, with uncontrolled amplification of cytokine production, leading to multiorgan failure and death. In addition to the airways and lungs, the cardiovascular system is often involved in COVID-19 early, reflected in the release of highly sensitive troponin and natriuretic peptides, which are all extremely prognostic, in particular, in those showing continued rise, along with cytokines such as interleukin-6. Inflammation in the vascular system can result in diffuse microangiopathy with thrombosis. Inflammation in the myocardium can result in myocarditis, heart failure, cardiac arrhythmias, acute coronary syndrome, rapid deterioration, and sudden death. Aggressive support based on early prognostic indicators with expectant management can potentially improve recovery. Appropriate treatment for heart failure, arrhythmias, acute coronary syndrome, and thrombosis remain important. Specific evidence-based treatment strategies for COVID-19 will emerge with ongoing global collaboration on multiple approaches being evaluated. To protect the wider population, antibody testing and effective vaccine will be needed to make COVID-19 history.

European Position Paper on Rhinosinusitis and Nasal Polyps 2020

The European Position Paper on Rhinosinusitis and Nasal Polyps 2020 is the update of similar evidence based position papers published in 2005 and 2007 and 2012. The core objective of the EPOS2020 guideline is to provide revised, up-to-date and clear evidence-based recommendations and integrated care pathways in ARS and CRS. EPOS2020 provides an update on the literature published and studies undertaken in the eight years since the EPOS2012 position paper was published and addresses areas not extensively covered in EPOS2012 such as paediatric CRS and sinus surgery. EPOS2020 also involves new stakeholders, including pharmacists and patients, and addresses new target users who have become more involved in the management and treatment of rhinosinusitis since the publication of the last EPOS document, including pharmacists, nurses, specialised care givers and indeed patients themselves, who employ increasing self-management of their condition using over the counter treatments. The document provides suggestions for future research in this area and offers updated guidance for definitions and outcome measurements in research in different settings. EPOS2020 contains chapters on definitions and classification where we have defined a large number of terms and indicated preferred terms. A new classification of CRS into primary and secondary CRS and further division into localized and diffuse disease, based on anatomic distribution is proposed. There are extensive chapters on epidemiology and predisposing factors, inflammatory mechanisms, (differential) diagnosis of facial pain, allergic rhinitis, genetics, cystic fibrosis, aspirin exacerbated respiratory disease, immunodeficiencies, allergic fungal rhinosinusitis and the relationship between upper and lower airways. The chapters on paediatric acute and chronic rhinosinusitis are totally rewritten. All available evidence for the management of acute rhinosinusitis and chronic rhinosinusitis with or without nasal polyps in adults and children is systematically reviewed and integrated care pathways based on the evidence are proposed. Despite considerable increases in the amount of quality publications in recent years, a large number of practical clinical questions remain. It was agreed that the best way to address these was to conduct a Delphi exercise . The results have been integrated into the respective sections. Last but not least, advice for patients and pharmacists and a new list of research needs are included. The full document can be downloaded for free on the website of this journal: http://www.rhinologyjournal.com.

Validation of the Seegene RV15 multiplex PCR for the detection of influenza A subtypes and influenza B lineages during national influenza surveillance in hospitalized adults

Background. The Serious Outcomes Surveillance Network of the Canadian Immunization Research Network (CIRN SOS) has been performing active influenza surveillance since 2009 (ClinicalTrials.gov identifier: NCT01517191). Influenza A and B viruses are identified and characterized using real-time reverse-transcriptase polymerase chain reaction (RT-PCR), and multiplex testing has been performed on a subset of patients to identify other respiratory virus aetiologies. Since both methods can identify influenza A and B, a direct comparison was performed.Methods. Validated real-time RT-PCRs from the World Health Organization (WHO) to identify influenza A and B viruses, characterize influenza A viruses into the H1N1 or H3N2 subtypes and describe influenza B viruses belonging to the Yamagata or Victoria lineages. In a subset of patients, the Seeplex RV15 One-Step ACE Detection assay (RV15) kit was also used for the detection of other respiratory viruses.Results. In total, 1111 nasopharyngeal swabs were tested by RV15 and real-time RT-PCRs for influenza A and B identification and characterization. For influenza A, RV15 showed 98.0 % sensitivity, 100 % specificity and 99.7 % accuracy. The performance characteristics of RV15 were similar for influenza A subtypes H1N1 and H3N2. For influenza B, RV15 had 99.2 % sensitivity, 100 % specificity and 99.8 % accuracy, with similar assay performance being shown for both the Yamagata and Victoria lineages.Conclusions. Overall, the detection of circulating subtypes of influenza A and lineages of influenza B by RV15 was similar to detection by real-time RT-PCR. Multiplex testing with RV15 allows for a more comprehensive respiratory virus surveillance in hospitalized adults, without significantly compromising the reliability of influenza A or B virus detection.

De novo transcriptome assembly of the Qatari pearl oyster Pinctada imbricata radiata

The pearl oyster Pinctada imbricata radiata is an iconic species in Qatar, representing an integral part of the nation's cultural heritage and one of the main economic foundations upon which the nation developed. During the early part of the 20th century, nearly half the Qatar population was involved in the pearl oyster industry. However, the fishery has undergone steady decline since the 1930s, and the species is now under threat due to multiple confounding pressures. This manuscript presents the first de novo transcriptome of the Qatari pearl oyster assembled into 30,739 non-redundant coding sequences and with a BUSCO completeness score of 98.4%. Analysis of the transcriptome reveals the close evolutionary distance to the conspecific animal Pinctada imbricata fucata but also highlights differences in immune genes and the presence of distinctive transposon families, suggesting recent adaptive divergence. This data is made available for all to utilise in future studies on the species.

Injectable human recombinant collagen matrices limit adverse remodeling and improve cardiac function after myocardial infarction

Despite the success of current therapies for acute myocardial infarction (MI), many patients still develop adverse cardiac remodeling and heart failure. With the growing prevalence of heart failure, a new therapy is needed that can prevent remodeling and support tissue repair. Herein, we report on injectable recombinant human collagen type I (rHCI) and type III (rHCIII) matrices for treating MI. Injecting rHCI or rHCIII matrices in mice during the late proliferative phase post-MI restores the myocardium's mechanical properties and reduces scar size, but only the rHCI matrix maintains remote wall thickness and prevents heart enlargement. rHCI treatment increases cardiomyocyte and capillary numbers in the border zone and the presence of pro-wound healing macrophages in the ischemic area, while reducing the overall recruitment of bone marrow monocytes. Our findings show functional recovery post-MI using rHCI by promoting a healing environment, cardiomyocyte survival, and less pathological remodeling of the myocardium.

Acute reperfusion for ST-elevation myocardial infarction in New Zealand (2015-2017): patient and system delay (ANZACS-QI 29)

AIM

Prompt access to cardiac defibrillation and reperfusion therapy improves outcomes in patients with ST-segment elevation myocardial infarction (STEMI). The study aim was to describe the 'patient' and 'system' delay in patients who receive acute reperfusion therapy for ST-elevation myocardial infarction (STEMI) in New Zealand.

METHODS

In 2015-17, 3,857 patients who received acute reperfusion therapy were captured in the All New Zealand Acute Coronary Syndrome Quality Improvement (ANZACS-QI) registry. 'Patient delay' is the time from symptom onset to first medical contact (FMC), and 'system delay' the time from FMC until reperfusion therapy (primary percutaneous coronary intervention (PCI) or fibrinolysis).

RESULTS

Seventy percent of patients received primary PCI and 30% fibrinolysis. Of those receiving fibrinolysis, 122 (10.5%) received pre-hospital fibrinolysis. Seventy-seven percent were transported to hospital by ambulance. After adjustment, people who were older, male and presented to a hospital without a routine primary PCI service were less likely to travel by ambulance. Patient delay: The median delay was 45 minutes for ambulance-transported patients and 97 minutes for those self-transported to hospital, with a quarter delayed by >2 hours and >3 hours, respectively. Delay >1 hour was more common in older patients, Māori and Indian patients and those self-transported to hospital. System delay: For ambulance-transported patients who received primary PCI, the median time was 119 minutes. For ambulance-transported patients who received fibrinolysis, the median system delay was 86 minutes, with Māori patients more often delayed than European/Other patients. For patients who received pre-hospital fibrinolysis the median delay was 46 minutes shorter. For the quarter of patients treated with rescue PCI after fibrinolysis, the median needle-to-rescue time was prolonged-four hours.

CONCLUSIONS

Nationwide implementation of the NZ STEMI pathway is needed to reduce system delays in delivery of primary PCI, fibrinolysis and rescue PCI. Ongoing initiatives are required to reduce barriers to calling the ambulance early after symptom onset.

The benthic sea-silk-thread displacement of a sessile bivalve, Pinctada imbricata radiata (Leach, 1819) in the Arabian-Persian Gulf

A number of molluscs within the Class Bivalvia are defined by their ability to secrete fine silk like threads known as byssus which are used to anchor themselves to solid substrates. With relatively few exceptions the majority of these species remain in a sedentary state throughout their life attached via their byssal threads. However, observations of adult Pinctada imbricata radiata pearl oysters made during this study revealed this species' ability to implement active movement. Byssal threads were secreted in a sequence of attachment and detachment phases, which resulted in the active displacement of the oyster. The oyster was observed, in the laboratory over a 9 day period, travelling a distance of 28cm in a horizontal path. After horizontal displacement, a vertical climbing phase was observed until the oyster reached the water surface at which point the byssus was discarded and the animal dropped, drifting in accordance with water current intensity. It is possible that these adaptations of byssal use are a result of environmentally induced evolutionary change within P. i. radiata.

ICare-ACS (Improving Care Processes for Patients With Suspected Acute Coronary Syndrome): A Study of Cross-System Implementation of a National Clinical Pathway

BACKGROUND

Efforts to safely reduce length of stay for emergency department patients with symptoms suggestive of acute coronary syndrome (ACS) have had mixed success. Few system-wide efforts affecting multiple hospital emergency departments have ever been evaluated. We evaluated the effectiveness of a nationwide implementation of clinical pathways for potential ACS in disparate hospitals.

METHODS

This was a multicenter pragmatic stepped-wedge before-and-after trial in 7 New Zealand acute care hospitals with 31 332 patients investigated for suspected ACS with serial troponin measurements. The implementation was a clinical pathway for the assessment of patients with suspected ACS that included a clinical pathway document in paper or electronic format, structured risk stratification, specified time points for electrocardiographic and serial troponin testing within 3 hours of arrival, and directions for combining risk stratification and electrocardiographic and troponin testing in an accelerated diagnostic protocol. Implementation was monitored for >4 months and compared with usual care over the preceding 6 months. The main outcome measure was the odds of discharge within 6 hours of presentation RESULTS: There were 11 529 participants in the preimplementation phase (range, 284-3465) and 19 803 in the postimplementation phase (range, 395-5039). Overall, the mean 6-hour discharge rate increased from 8.3% (range, 2.7%-37.7%) to 18.4% (6.8%-43.8%). The odds of being discharged within 6 hours increased after clinical pathway implementation. The odds ratio was 2.4 (95% confidence interval, 2.3-2.6). In patients without ACS, the median length of hospital stays decreased by 2.9 hours (95% confidence interval, 2.4-3.4). For patients discharged within 6 hours, there was no change in 30-day major adverse cardiac event rates (0.52% versus 0.44%; P=0.96). In these patients, no adverse event occurred when clinical pathways were correctly followed.

CONCLUSIONS

Implementation of clinical pathways for suspected ACS reduced the length of stay and increased the proportions of patients safely discharged within 6 hours.

CLINICAL TRIAL REGISTRATION

URL: https://www.anzctr.org.au/ (Australian and New Zealand Clinical Trials Registry). Unique identifier: ACTRN12617000381381.

Incorporating airway examination photography into the electronic record

BACKGROUND

Photography of the airway has been used in research to validate preoperative airway assessment and the likelihood of identifying the difficult-to-mask ventilate and/or intubate patient. Up till now, no study has demonstrated the perceived utility of incorporation of airway photographs into the anesthesia preassessment.

METHODS

The University of Florida Health Presurgical Clinic routinely incorporates three photographs of all adult patients during their preanesthesia visit. The first is a head-on view of the patient opening the mouth widely as part of a Mallampati examination, and the second and third are side views of the patient prognathing and with the neck in maximal extension, respectively. After IRB approval, providers of anesthesia were surveyed regarding their opinions on the perceived value of the new process. Chi-square tests were used to determine if the responses to each question significantly differed from the distribution that would be predicted by chance. P < 0.05 was considered statistically significant.

RESULTS

The survey was emailed to 180 individuals, with 145 responding. The responses significantly (P < 0.0001) indicated that the photographs helped the providers plan care for their patients and improved their satisfaction with the preoperative assessment. Technical and educational barriers were overcome using iterative Plan-Do-Study-Act cycles and coaching, respectively.

CONCLUSIONS

Photographs of the airway assessment can successfully be taken and incorporated into an electronic medical record in a busy presurgical clinic. The pictures provide additional perceived value to the traditional written assessment of a patient's airway examination by someone else.

A new species of leucosiid crab (Decapoda: Brachyura: Leucosiidae) from the Arabian Gulf

The Indo-West Pacific genus Coleusia Galil 2006, was recently described and now comprises seven species. We describe a new species from the western Arabian Gulf, Coleusia janani n. sp. The new species is closely related to the congener C. biannulata (Tyndale-Biscoe & George, 1962), and can be distinguished from other species at these genus congeners mainly by the straight upward apical shape of the male first pleopod (G1). An updated identification key to the species of Coleusia, as well as an overview of the geographical distribution of the species included in the genus are also presented.

Myocardial Infarction Without Obstructive Coronary Artery Disease is Not a Benign Condition (ANZACS-QI 10)

BACKGROUND

Non-obstructive coronary artery disease (CAD) on coronary angiography after myocardial infarction (MI) is associated with a lower risk of adverse outcomes, but the prognosis may not be benign. Our aim was to assess outcomes in MI with and without obstructive CAD, and in an age and sex matched comparison cohort without known cardiovascular disease.

METHODS

We performed a single centre analysis of consecutive patients undergoing coronary angiography for MI between 2007 and 2012. Patients were classified into those with obstructive CAD (≥50% epicardial coronary artery stenosis) and those without obstructive CAD (<50%). Myocardial infarction patient data was collected in an electronic registry and linked anonymously to national hospitalisation and mortality records. Age and sex matched patients without known CVD were identified from the community PREDICT cohort.

RESULTS

Of the 2070 patients with MI, 302 (15%) had non-obstructive CAD. Compared to patients with obstructive disease they were younger (mean 57 v 61 years, p<0.001), more likely to be women (50% vs 23%, p<0.001), to be of Maori or Pacific vs. European ethnicity (p<0.001), more likely to be lifelong non-smokers (46% v 38%, p=0.02), non-diabetic (80v 73%, p <0.01), have no ST-segment deviation (78% v 46%, p<0.001), and have a low risk Global Registry of Acute Coronary Events acute coronary syndrome (GRACE ACS) score (54 v 35%, p<0.001). They were also less likely to receive 'triple therapy' secondary prevention medications (81% v 94%, p<0.0001). The cumulative two-year Kaplan-Maier composite outcome of mortality or non-fatal MI was 14.3% for MI with obstructive CAD, 4.6% for MI without obstructive disease, and 2.2% for patients without prior CVD (p<0.001).

CONCLUSION

Myocardial infarction without obstructive coronary disease is common (∼1 in 7 patients) and is not clinically benign, with an adverse outcome rate double that of age and sex matched patients without CVD.