Incidence and risk factors for major bleeding events in atrial fibrillation patients on direct oral anticoagulant therapy: data from the National Patient-Centered Clinical Research Network

Background

Direct oral anticoagulation (DOACs) prevent stroke in patients with atrial fibrillation (AF) and have a superior safety profile compared with vitamin K antagonists (VKA). Yet, better definition of incidence and risk factors for major bleeding associated with DOACs in clinical practice may be important given emerging stroke prevention technologies, both pharmacologic and nonpharmacologic.

Purpose

To describe the incidence of and risk factors for major bleeding in individuals with AF on DOAC therapy.

Methods

We reviewed electronic health record data for two patient cohorts with AF prescribed DOACs: (1) Duke University Health System (DUHS) (2010–2018) and (2) Sites within the Patient-Centered Clinical Research Network (PCORnet) (2015–2019) which had ≥6 years assimilated data from both inpatient and outpatient encounters (7 sites). In each cohort, we assessed the 5-year incidence of major bleeding events defined as hospitalization for intracranial hemorrhage, or hospitalization for gastro-intestinal bleeding or procedure to control bleeding accompanied by transfusion within ±7 days or death within 30 days. Multivariable Fine-Gray proportional hazards modeling in each cohort was performed to evaluate independent risk factors for major bleeding on DOAC therapy.

Results

The cohorts included 10,625 patients (DUHS) and 58,321 patients (PCORnet) with AF. Major bleeding events occurred within 5 years of diagnosis in 639 (7.9%) of DUHS patients and 2568 (6.6%) of PCORnet patients (Table 1). The DUHS model predicted time to first major bleeding event with a C-index of 0.756 (95% CI 0.737, 0.775) and the PCORNet model had a c-index of 0.745 (0.736, 0.755) (Table 2). Independent factors associated with major bleeding consistent across both models (p<0.001 in PCORnet for all unless noted) were higher CHA2DS2-VASc scores, lower eGFR, anemia (HR per 1-point increase in hemoglobin up to 12 g/dL 0.79 [0.76, 0.82]), prior major bleeding (HR 2.70 [2.22, 3.30]), cancer (HR 1.23 [1.12, 1.36]), recent cardiac surgery (HR 0.70 [0.51, 0.97]; p=0.030), alcohol use (HR 1.56 [1.29, 1.88]), aspirin use (HR 1.44 [1.32, 1.57]), and selective serotonin reuptake inhibitor use (HR 1.30 [1.19, 1.42]).

Conclusions

Across a large and geographically diverse contemporary population, risk of bleeding on DOAC for stroke prevention in AF remains a frequent and important clinical problem. There is an unmet need for stroke prevention therapies with improved safety profiles. We identified risk factors for major bleeding events on DOAC therapy, some of which are not represented in traditional risk scores, which may inform shared decision making for stroke prevention.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Bayer Pharmaceuticals

Diagnosing ventilator-associated pneumonia (VAP) in UK NHS ICUs: the perceived value and role of a novel optical technology

BACKGROUND

Diagnosing ventilator-associated pneumonia (VAP) in an intensive care unit (ICU) is a complex process. Our aim was to collect, evaluate and represent the information relating to current clinical practice for the diagnosis of VAP in UK NHS ICUs, and to explore the potential value and role of a novel diagnostic for VAP, which uses optical molecular alveoscopy to visualise the alveolar space.

METHODS

Qualitative study performing semi-structured interviews with clinical experts. Interviews were recorded, transcribed, and thematically analysed. A flow diagram of the VAP patient pathway was elicited and validated with the expert interviewees. Fourteen clinicians were interviewed from a range of UK NHS hospitals: 12 ICU consultants, 1 professor of respiratory medicine and 1 professor of critical care.

RESULTS

Five themes were identified, relating to [1] current practice for the diagnosis of VAP, [2] current clinical need in VAP diagnostics, [3] the potential value and role of the technology, [4] the barriers to adoption and [5] the evidence requirements for the technology, to help facilitate a successful adoption. These themes indicated that diagnosis of VAP is extremely difficult, as is the decision to stop antibiotic treatment. The analysis revealed that there is a clinical need for a diagnostic that provides an accurate and timely diagnosis of the causative pathogen, without the long delays associated with return of culture results, and which is not dangerous to the patient. It was determined that the technology would satisfy important aspects of this clinical need for diagnosing VAP (and pneumonia, more generally), but would require further evidence on safety and efficacy in the patient population to facilitate adoption.

CONCLUSIONS

Care pathway analysis performed in this study was deemed accurate and representative of current practice for diagnosing VAP in a UK ICU as determined by relevant clinical experts, and explored the value and role of a novel diagnostic, which uses optical technology, and could streamline the diagnostic pathway for VAP and other pneumonias.

P935Effect of hypertension and systolic blood pressure on cardiovascular and limb outcomes in patients with symptomatic peripheral artery disease: the EUCLID trial

Background

Hypertension is a risk factor for major adverse cardiac events (MACE) in patients with symptomatic peripheral artery disease (PAD).

Purpose

The effects of a history of hypertension and baseline systolic blood pressure (SBP) on MACE and major adverse limb events (MALE), including acute limb ischemia and major amputation, were evaluated in the Examining Use of tiCagreLor In paD (EUCLID) trial.

Methods

EUCLID randomized 13,885 patients with PAD and found no benefit of ticagrelor compared with clopidogrel on risk of MACE or MALE. The median duration of follow up was approximately 30 months. This post hoc, subgroup analysis evaluated the effects of hypertension history at baseline on the hazard for MACE and MALE. An adjusted restricted cubic spline regression analysis evaluated the association of SBP with MACE and MALE.

Results

A clinical history of hypertension was present in 10,857 (78%) patients at baseline and these patients were more likely to be older, female, white or African American, and reside in North America compared with the 3026 without hypertension. Hypertension was associated with a higher prevalence of concomitant cardiovascular diseases, polyvascular disease, diabetes, and prior coronary interventions. MACE occurred at a rate of 4.63 events/100 pt-yrs in participants with hypertension and 3.64 events/100 pt-yrs in participants without hypertension, (adjusted hazard ratio [aHR] 0.94, 95% CI 0.82–1.08; p=0.38). MALE occurred at a rate of 1.11 events/100 pt-yrs in those with hypertension and 1.38 events/100 pt-yrs in those without hypertension (p=0.054) (aHR 0.93 (95% CI 0.73, 1.18) p=0.55. The adjusted spline model for MACE and SBP demonstrated a significantly non-linear relationship with a HR 1.08 (95% CI 1.01, 1.15), p=0.0275 for every 10-unit decrease <135 mmHg SBP and HR 1.11 (1.06, 1.16), p<0.0001 for every 10-unit increase >135 mmHg (figure). There was no association between baseline SBP and MALE events.

Conclusions

A history of hypertension was not associated with a higher adjusted hazard for MACE or MALE in participants with PAD. In contrast, SBP at baseline was associated with increased risk of MACE at values both above and below 135 mmHg.

Acknowledgement/Funding

EUCLID was sponsored by AstraZeneca

Cost implications for the NHS of using the Alere™ i Influenza A & B near patient test with nasal swabs

BACKGROUND

Influenza is an acute viral infection of the respiratory tract. A rapid confirmatory diagnosis of influenza is important, since it is highly transmissible and outbreaks of influenza within the hospital setting increase morbidity and mortality. The objective of this study was to evaluate the cost implications, from the perspective of the UK NHS, of using on-label nasal swabs with the Alere™ i Influenza A & B test in a near patient setting.

METHODS

A cost consequence model was developed. The time horizon of the model was from hospital admission on suspicion of influenza until the end of treatment (following a diagnosis of influenza or discharge from hospital). Data on the prevalence of influenza and the sensitivity and specificity of the Alere™ i Influenza A & B test came from two prospective observational diagnostic accuracy studies. Costs were obtained from published resources. Uncertainties in the model data were investigated using deterministic, one-way sensitivity analyses.

RESULTS

Using the Alere™ i Influenza A & B point of care test with nasal swabs (on label) in NHS medical assessment units and emergency departments could save approximately £242,730 per 1000 adults presenting with influenza-like symptoms. The main cause for this was reduced times to availability of the result compared with the laboratory RT-PCR test. Other key drivers of savings were the cost of isolation, the prevalence of influenza, the specificity of the test, and the availability of isolation resources.

CONCLUSIONS

The Alere™ i Influenza A & B point of care test would have greatest impact in hospitals that have extensive delays in the time to receive a result. Sensitivity analyses identified the model parameters which would have greatest effect on the result and confirmed that assumptions were conservative, i.e. did not change key results.

Management of cardiogenic shock in the setting of ST-elevation myocardial infarction: controversies and future directions

The treatment of patients with ST-segment elevation myocardial infarction (STEMI) has changed dramatically since reperfusion therapy has been adopted more commonly, yet 5-10% of patients still develop cardiogenic shock and remain a therapeutic challenge in the setting of STEMI. In this review, we outline the available evidence from randomized controlled trials and registries, including risk factors, diagnostic tools, and various treatments. The main focus of this report is on the currently available treatment options (revascularization, intra-aortic balloon counterpulsation), emerging treatment options (percutaneous hemodynamic support, extracorporeal membrane oxygenation), and ongoing efforts to design systems of care to more efficiently care for these patients.

Abstract P51: Trends in Utilization of Invasive Cardiac Procedures in North Carolina

Background: Concerns around utilization of coronary revascularization remain in the US. We aimed to understand the temporal trends and variation in invasive diagnostic cardiac catheterization (Cath), percutaneous intervention (PCI) and coronary artery bypass surgery (CABG) in North Carolina from 2003-2009.

Methods: All Cath, PCI, and CABG procedures performed in North Carolina from 2003-2009 were identified using hospital-reported data submitted in a License Renewal Application by all catheterization labs for the North Carolina State Medical Facilities Plan. Rates of procedure use, ratios of PCI to Cath, CABG to Cath, and CABG to PCI were compared over time and between hospitals. Hospitals that performed at least 25 Cath, 25 PCI, and 25 CABG were included in the variation analysis.

Results: From 2003-2009, there was an observed decline in the annual rate of all procedures, 16% for Cath, 9% for PCI, 27% for CABG. However, the ratio of PCI to diagnostic Cath over the time period increased by 10%, rising to 51% in 2009, while the ratio of CABG to Cath decreased by 10% (see Figure). Of the 119 hospitals in North Carolina, 21 hospitals reported performing more than 25 Cath, 25 PCI and 25 CABG each year from 2003-2009. Hospital level analysis also showed evidence of significant variation in the ratio of both PCI to Cath (10% to 90%, p<0.05) and CABG to Cath (5-35%, p<0.05).

Conclusions: Although the use of all cardiac procedures declined, the ratio of PCI to Cath increased over the study period. There was significant variation in the mode of revascularization (CABG and PCI) across hospital systems in North Carolina. Further investigation into revascularization decisions is warranted.

Figure.Trends in Volume and Rates of Diagnostic Cath, PCI, and CABG in North Carolina from 2003-2009.

Lack of effect of cold water prawns on plasma cholesterol and lipoproteins in normo-lipidaemic men

OBJECTIVE

Dietary guidelines for the prevention of coronary heart disease (CHD) have restricted the intake of foods rich in dietary cholesterol, on the grounds that the dietary cholesterol will increase blood cholesterol. In the case of shellfish, this recommendation may limit the intake of a valuable dietary source of long chain n-3 polyunsaturated fatty acids (LC n-3 PUFA). The objective of this study was to undertake a dietary intervention to determine the effects of cold water prawns on plasma lipids and lipoproteins.

METHODS

23 healthy male subjects were randomised to receive either 225 g of cold water prawns or an equivalent weight of fish ('crab') sticks as a control for 12 weeks in a cross-over design. Blood samples were taken at the beginning and end of each intervention for the determination of plasma lipids and lipoproteins by routine enzymatic assays and iodixanol density gradient centrifugation respectively.

RESULTS

The diets were well matched for the intake of total energy and macronutrients, and body weight remained stable throughout the study. The prawn intervention increased the intake of dietary cholesterol to 750 mg/d against 200 mg/d on the control. The intake of LC n-3 PUFA from prawns was estimated to be between 0.5-0.7 g/d. The consumption of prawns produced no significant effects on the concentration of plasma total or LDL cholesterol, triacylglycerol, HDL cholesterol or apolipoproteins A-I and B relative to the control, or within each intervention group over time. There was also no significant effect on LDL density (particle size) relative to the control, or any difference between and within treatments in total plasma lipoprotein profiles by density gradient centrifugation.

CONCLUSION

These findings provide evidence to suggest that the consumption of cold water prawns, at least in healthy, male subjects, should not be restricted on the grounds of this seafood producing an adverse effect on plasma LDL cholesterol.

Drug-eluting versus bare metal stenting in acute myocardial infarction. A clinical review

Coronary heart disease is a leading cause of death around the world. The treatment of acute myocardial infarction has evolved with the advent of novel thrombolytic agents, anticoagulants, antiplatelets, and innovative percutaneous techniques. The development of drug-eluting stents has dramatically lowered the risk of in-stent restenosis compared to bare metal stents. Clinicians in the United States and Europe have begun utilizing DES in the setting of AMI despite the fact that no practice guidelines exist to support their use. Lingering concerns exist about the reported increased risk of early and late stent thrombosis after DES implantation. In this review, we will highlight the >7,500 patients studied in randomized controlled trials and >30,000 registry patients comparing drug-eluting and bare metal stent implantation during acute myocardial infarction. In the selected patient populations of the 13 randomized controlled trials comparing drug-eluting and bare metal stent implantation, death/re-infarction/stent thrombosis were not different between groups while target vessel revascularization was significantly lower in the drug-eluting stent patients. In the "real world" registry studies, mortality/target vessel revascularization/stent thrombosis were less frequent in the first year after drug-eluting stent implantation while re-infarction was not different between the groups. While multiple questions remain regarding long-term follow up and especially late stent thrombosis, it appears that drug-eluting stents are effective at decreasing target vessel revascularization while not being associated with an elevated risk of death/re-infarction/stent thrombosis in the first year post myocardial infarction.

The hypo-echoic cortical rim in lupus nephritis

Hypo-echoic cortical rims are an unusual ultrasound finding in patients with renal disease. A case report is presented of a patient with lupus nephritis who demonstrated hypo-echoic cortical rims. A brief review of the pathological causes of hypo-echoic cortical rims is given.

Management of tracheobronchial disruption resulting from blunt trauma

Delayed diagnosis of tracheobronchial disruption resulting from blunt trauma continues to cause major morbidity and death. At the University of Louisville from 1968 to 1982, 13 patients had tracheobronchial disruption resulting from blunt trauma. All injuries were caused by motor vehicle accidents. Disruptions were located in the trachea in six patients and in the right bronchus in seven patients. Physical findings included: subcutaneous emphysema (11 patients), respiratory distress (10 patients), hemoptysis (six patients), and flail chest (four patients). Four patients (30%) died, three from multiple major associated injuries and the other before therapy could be instituted. Among the nine survivors, six had immediate diagnosis and prompt surgical treatment, which consisted of suture repair in five and pneumonectomy in the other patient. Two patients had delay in diagnosis, and repair was attempted at 4 and 30 days, respectively; bronchial stricture resulted in one and pneumonectomy, empyema, and bronchopleural fistula in the other. Another patient with a bronchial mucosal tear was treated nonoperatively without complication. Tracheobronchial disruption should always be considered with massive blunt chest trauma. Repeated bronchoscopy is indicated for unexplained pleural air leaks, lobar atelectasis, or persistent pneumothorax. Prompt diagnosis and expeditious surgical therapy result in fewer complications and increased survival.

Burkitt's lymphoma in the femoral triangle of a white american male

A teenage white male was recently evaluated for a rapidly enlarging mass in the right groin. Biopsy of the mass disclosed Burkitt's lymphoma. Aggressive therapy was instituted, including extirpative surgery, followed by chemotherapy and radiation therapy. Using these combined modalities, it was possible to eliminate the lymphoma. Unfortunately, severe pancytopenia and immunosuppression developed and the patient died of gram-negative sepsis. This disease should be considered in the differential diagnosis of any rapidly enlarging solid tumor in a young patient.