Oral Presentation No. 53 Dose-related preprocedural patency of the infarct-related artery after zalunfiban (RUC-4) administration upon arrival at the catheterization laboratory in ST-elevation myocardial infarction: insights from the phase IIa study

Background

The importance of time to reperfusion after ST-elevation myocardial infarction (STEMI) is well established. Pre-hospital use of glycoprotein IIb/IIIa (GPIIb/IIIa) inhibitors improves pre-percutaneous coronary intervention (PCI) perfusion rates, but they require intravenous administration and continuous infusions and so are difficult for ambulance services to administer. Zalunfiban (RUC-4) is a novel, subcutaneously administered, GPIIb/IIIa inhibitor specifically developed to facilitate pre-hospital administration, thereby maximizing the chance for early reperfusion. This sub-analysis investigated the incidence of complete reperfusion (TIMI grade 3 flow) before primary PCI in patients treated with zalunfiban on arrival at the catheterization laboratory as a function of the dose of zalunfiban.

Material and methods

This was a prospective, single-centre, open-label, phase IIa study designed to assess the pharmacodynamics, pharmacokinetics, and tolerability of zalunfiban in patients with STEMI undergoing primary PCI. Zalunfiban was administered immediately upon arrival at the catheterization lab, which was ∼10–15 minutes before the initial angiogram used to assess TIMI grade flow.

Results and conclusion

A total of 27 patients received a weight-adjusted subcutaneous injection of zalunfiban in escalating doses (0.075 mg/kg [n = 8], 0.090 mg/kg [n = 9], or 0.110 mg/kg [n = 10]). Of these, 25 patients were evaluable for angiographic analysis. TIMI flow grade 3 pre-PCI was observed in 1/7, 2/9 and 5/9 patients and showed a dose-related effect (Ptrend = 0.04). The ongoing international, phase III, double-blinded, randomized, placebo-controlled, CELEBRATE trial is designed to assess whether a single, ambulance-based pre-hospital injection of zalunfiban results in improved clinical outcome.

Funding

This study was supported by CeleCor Therapeutics.

Society of pediatric liver transplantation: Current registry status 2011-2018

BACKGROUND

SPLIT was founded in 1995 in order to collect comprehensive prospective data on pediatric liver transplantation, including waiting list data, transplant, and early and late outcomes. Since 2011, data collection of the current registry has been refined to focus on prospective data and outcomes only after transplant to serve as a foundation for the future development of targeted clinical studies.

OBJECTIVE

To report the outcomes of the SPLIT registry from 2011 to 2018.

METHODS

This is a multicenter, cross-sectional analysis characterizing patients transplanted and enrolled in the SPLIT registry between 2011 and 2018. All patients, <18 years of age, received a first liver-only, a combined liver-kidney, or a combined liver-pancreas transplant during this study period.

RESULTS

A total of 1911 recipients from 39 participating centers in North America were registered. Indications included biliary atresia (38.5%), metabolic disease (19.1%), tumors (11.7%), and fulminant liver failure (11.5%). Greater than 50% of recipients were transplanted as either Status 1A/1B or with a MELD/PELD exception score. Incompatible transplants were performed in 4.1%. Kaplan-Meier estimates of 1-year patient and graft survival were 97.3% and 96.6%. First 30 days of surgical complications included reoperation (31.7%), hepatic artery thrombosis (6.3%), and portal vein thrombosis (3.2%). In the first 90 days, biliary tract complications were reported in 13.6%. Acute cellular rejection during first year was 34.7%. At 1 and 2 years of follow-up, 39.2% and 50.6% had normal liver tests on monotherapy (tacrolimus or sirolimus). Further surgical, survival, allograft function, and complications are detailed.

P5535Gender differences with short-term vs 12 months dual antiplatelet therapy in patients with acute coronary syndrome treated with the COMBO dual therapy stent: a 1-year analysis of the REDUCE trial

Background

Gender differences in the thrombotic and bleeding risk have been suggested to condition the benefits of antithrombotic therapies in Acute Coronary Syndrome (ACS) patients, and mainly among those undergoing percutaneous coronary interventions with drug eluting stents (DES). Therefore, the impact of gender on the optimal duration of dual antiplatelet therapy (DAPT) treated is still unclear and was therefore the aim of the present sub-study.

Methods

REDUCE is a prospective, multicenter, randomized, investigator-initiated study, designed to enroll 1500 ACS patients after treatment with the COMBO Dual Stent Therapy, based on a non-inferiority design. Patients were randomized in a 1:1 fashion to either 3 or 12 months of DAPT. Primary study endpoint was a composite of all-cause mortality, myocardial infarction, definite/probable stent thrombosis (ST), stroke, target-vessel revascularization (TVR) and bleeding (BARC II, III, V) at 12 months. Secondary endpoints were cardiovascular mortality and the individual components of the primary endpoint.

Results

From June 2014 to May 2016 300 women and 1196 men were randomized in the trial. Among them 43.7% of females and 51.9% of males were assigned to the 3 months DAPT treatment. Baseline characteristics were well matched between the two arms, but of a lower rate of TIMI flow <3 (p<0.001) and lower systolic blood pressure (p<0.05) among women and a more advanced age (p=0.05) among men receiving a shorted DAPT. At 1 year follow-up, no difference in the primary endpoint was observed according to DAPT duration (females: 6.9% vs 5.9%, HR [95% CI]=1.19 [0.48–2.9], p=0.71; males: 8.2% vs 9%, HR [95% CI]=0.92 [0.63–1.35], p=0.67). Results were confirmed after correction for baseline differences (females: adjusted HR [95% CI]=1.12 [0.45–2.78], p=0.81; males: adjusted HR [95% CI]=0.90 [0.61–1.32], p=0.60). Comparable rates of survival, thrombotic (MI, stent thrombosis, TVR, stroke) and bleeding events were observed with the two DAPT strategies, with no impact of gender.

Conclusions

The present study shows that among ACS patients randomized in the REDUCE trial, a 3 months DAPT strategy offers comparable results as compared to a standard 12 months DAPT at 1-year follow-up in both male and female gender.

Acknowledgement/Funding

None

[A woman with excessive dynamic airway collapse]

BACKGROUND

'Excessive dynamic airway collapse' (EDAC) is a form of tracheamalacia, that does not affect the rings of cartilage on the anterior side of the trachea, but in which the posterior wall of the trachea collapses during inspiration and expiration.

CASE DESCRIPTION

An 80 year-old woman presented to the accident and emergency department with dyspnoea and severe inspiratory and expiratory stridor, with sudden onset a few hours previously. Following a series of investigations, she was shown to have a narrowing of the trachea, radiating from the posterior wall. The diagnosis was EDAC. Because her saturation levels were acceptable and she was otherwise well she was admitted to the intensive care unit for observation only. The symptoms disappeared within 4 days, without intervention.

CONCLUSION

EDAC is usually asymptomatic, but when symptoms arise the clinical picture is often confused with asthma, COPD or laryngeal oedema. The diagnostic gold standard is bronchoscopy. Therapy is chosen on the basis of severity of the symptoms.

[Approaching psychological problems like a general practitioner]

An important cause of the high prescription levels of psychotropic medication for psychological symptoms is that these symptoms are assessed according to the same model as applied for physical symptoms, the disease model. This has led to a one-sided medical approach to psychological symptoms. A person-centred approach offers an alternative; the positive aspects of the disease-centred approach are retained and attention for the patient and his/her context become the central focal point for the general practitioner. Important elements of the person-centred approach are empathy, a good doctor-patient relationship, a shared approach to problem definition and understanding of the patient's problem, development of a therapeutic alliance, and a focus on the patient's hopes and expectations. If additional primary care-based treatment by mental health practice nurses is indicated, this model could be suitable since it is based on patients' strengths and focuses on personal growth rather than reduction of symptoms.

[A young man with a painful knee]

A 23-year-old man injured his left knee. A CT scan showed a dislocation of the proximal tibiofibular joint. Closed reduction of the dislocation was done successfully under procedural sedation and analgesia. Afterwards he was treated with a pressure bandage and immobilisation of the knee for 2 weeks.

The influence of residential distance on time to treatment in ST-elevation myocardial infarction patients

Aims

To evaluate the relation between residential distance and total ischaemic time in patients with acute ST-elevation myocardial infarction (STEMI).

Methods

STEMI patients were transported to the Isala Hospital Zwolle with the intention to perform primary percutaneous coronary intervention PCI (pPCI) from 2004 until 2010 (n = 4149). Of these, 1424 patients (34 %) were referred via a non-PCI ‘spoke' centre (‘spoke’ patients) and 2725 patients (66 %) were referred via field triage in the ambulance (ambulance patients).

Results

A longer residential distance increased median total ischaemic time in ‘spoke’ patients (0–30 km: 228 min, >30-60 km: 235 min, >60-90 km: 264 min, p < 0.001), however not in ambulance patients (0–30 km: 179 min, >30-60 km: 175 min, >60-90 km: 186 min, p = 0.225). After multivariable linear regression analysis, in ‘spoke’ patients residential distance of >30-60 km compared with 0–30 km was not independently associated with ischaemic time; however, a residential distance of >60-90 km (exp (B) = 1.11, 95 % CI 1.01-1.12) compared with 0–30 km was independently related with ischaemic time. In ambulance patients, residential distance of >30-60 and >60-90 km compared with 0–30 km was not independently associated with ischaemic time.

Conclusion

A longer distance from the patient’s residence to a PCI centre was associated with a small but significant increase in time to treatment in ‘spoke’ patients, however not in ambulance patients. Therefore, referral via field triage in the ambulance did not lead to a significant increase in time to treatment, especially at long distances (up to 90 km).

Application of spectral phase shaping to high resolution CARS spectroscopy

By spectral phase shaping of both the pump and probe pulses in coherent anti-Stokes Raman scattering (CARS) spectroscopy we demonstrate the extraction of the frequencies, bandwidths and relative cross sections of vibrational lines. We employ a tunable broadband Ti:Sapphire laser synchronized to a ps-Nd:YVO mode locked laser. A high resolution spectral phase shaper allows for spectroscopy with a precision better than 1 cm(-1) in the high frequency region around 3000 cm(-1). We also demonstrate how new spectral phase shaping strategies can amplify the resonant features of isolated vibrations to such an extent that spectroscopy and microscopy can be done at high resolution, on the integrated spectral response without the need for a spectrograph.

Outcomes of adults with acute myelogenous leukemia in remission given 550 cGy of single-exposure total body irradiation, cyclophosphamide, and unrelated donor bone marrow transplants

On the basis of observations from dog models and human studies, we hypothesized that a low-dose (550 cGy), single-exposure total body irradiation (TBI)-based regimen would result in improved survival when given to adult patients with acute myelogenous leukemia (AML) who were undergoing unrelated donor bone marrow transplantation in complete remission (CR). The regimen consisted of single exposure (550 cGy) of TBI given at a high dose rate (30 cGy/min) and cyclophosphamide. Graft-versus-host disease prophylaxis consisted of cyclosporine, methotrexate, and corticosteroids. Thirty-two consecutive adult patients (median age, 47 years) with AML in CR (15 in CR 1 and 17 in CR > or =2) were treated. Sixteen patients (50%) were alive and in remission at last follow-up (median, 2.2 years; range, 0.6-4.0 years). Kaplan-Meier estimates of overall and leukemia-free survival at 3 years were 55% +/- 14% (mean +/- SE) and 57% +/- 14% in CR 1 patients and were both 39% +/- 12% in CR > or =2 patients. Transplant-related mortality was 13% for patients in CR 1 and 41% for those in CR > or =2. Only 1 patient (3%) experienced fatal regimen-related organ toxicity, and only 1 had grade III or IV acute graft-versus-host disease. Graft failure was not observed. Relapse occurred in 22% of patients. This low-dose (550 cGy), single-exposure TBI-based regimen resulted in good survival and a low risk of fatal regimen-related organ toxicity in adult patients with AML who underwent unrelated donor bone marrow transplantation in CR.

Gap junctions in the rabbit sinoatrial node

In comparison to the cellular basis of pacemaking, the electrical interactions mediating synchronization and conduction in the sinoatrial node are poorly understood. Therefore, we have taken a combined immunohistochemical and electrophysiological approach to characterize gap junctions in the nodal area. We report that the pacemaker myocytes in the center of the rabbit sinoatrial node express the gap junction proteins connexin (Cx)40 and Cx46. In the periphery of the node, strands of pacemaker myocytes expressing Cx43 intermingle with strands expressing Cx40 and Cx46. Biophysical properties of gap junctions in isolated pairs of pacemaker myocytes were recorded under dual voltage clamp with the use of the perforated-patch method. Macroscopic junctional conductance ranged between 0.6 and 25 nS with a mean value of 7.5 nS. The junctional conductance did not show a pronounced sensitivity to the transjunctional potential difference. Single-channel recordings from pairs of pacemaker myocytes revealed populations of single-channel conductances at 133, 202, and 241 pS. With these single-channel conductances, the observed average macroscopic junctional conductance, 7.5 nS, would require only 30-60 open gap junction channels.

Tumour necrosis factor alpha alters the expression of connexin43, connexin40, and connexin37 in human umbilical vein endothelial cells

Tumour necrosis factor alpha (TNF-alpha) plays an important role in orchestrating inflammatory responses with the vascular endothelium as main target cell type, and was found to promote migration of endothelial cells, as occurs in wound healing processes. Substantial evidence exists that endothelial cell migration in wound healing is related to changes in cell coupling by means of gap junctions. Gap junctions are agglomerates of cell-to-cell channels that allow direct electrical and metabolic communication between cells. The authors have investigated whether TNF-alpha alters the expression of gap junction proteins (connexins, Cx) between human umbilical vein endothelial cells (HUVEC), thereby changing the extent of intercellular communication, as measured by dye coupling. Under control conditions, Cx43, Cx40, and Cx37 protein and mRNA were present in HUVEC. After exposure to 0.5 nM TNF-alpha for 48 h, however, the authors were no longer able to detect Cx37 and Cx40 protein, whereas Cx43 levels seemed unaltered but showed more perinuclear staining. After 24 and 48 h exposure to TNF-alpha, levels of Cx37 and Cx40 mRNA, were reduced, while the level of Cx43 mRNA remained unaltered, suggesting transcriptional regulation. If TNF-alpha was removed from the medium, Cx37 and Cx40 expression was restored within 24 h. The modulation of connexin expression by TNF-alpha resulted in a decrease in dye coupling of 40%.

Recovery from cytomegalovirus infection is associated with activation of peripheral blood lymphocytes

The number of CD8bright and CD56+ lymphocytes in the peripheral blood and their activation status were monitored by flow cytometry in 23 renal transplant recipients with cytomegalovirus (CMV) infection and were correlated with the virus load (as determined by CMV antigenemia) and clinical symptoms. Recovery from CMV infection coincided with expansion of the CD8bright and CD56+ subsets and with increased expression of the activation marker HLA-DR. Primary infection was associated with activation of both subsets, whereas during secondary infection, mainly CD8bright cells responded. Progressive CMV disease (requiring antiviral treatment) and relapse occurred in association with low numbers of activated CD8bright and CD56+ cells. Lymphocyte activation and antibody responses against CMV often occurred simultaneously, but different kinetics of these responses in some patients indicated that cellular responses are necessary to control viral replication, whereas humoral responses alone may be insufficient. Monitoring of lymphocyte activation may provide clinically useful information during CMV infection.

Quantitative measurement of cytomegalovirus-specific IgG and IgM antibodies in relation to cytomegalovirus antigenaemia and disease activity in kidney recipients with an active cytomegalovirus infection

In a longitudinal investigation 103 kidney recipients were studied with respect to the development of cytomegalovirus (CMV) specific antibodies of the IgG and IgM class, in relation to the detection of CMV antigenaemia (immediate early antigen, IEA), in weekly obtained blood samples during the first 3 months after transplantation. In 15 out of 49 (31%) seronegative patients a primary infection occurred, which was characterized by a quick rise in IgM antibody followed by a slower production of IgG antibody, high maximum numbers of IEA+ cells, and a CMV syndrome in 11 patients. In 35 out of 54 (65%) seropositive patients a secondary infection occurred. After a post-operative fall in the IgG antibody, which was also found in patients without an active infection and which was accompanied by a similar drop in serum albumin and IgG, a second dip in IgG antibody was found 6 days before the first IEA+ leucocyte appeared in the blood. This was followed by a significant increase, indicative of an active immune response in consequence of the infection, 18 days later. In 31 of these 35 patients an IgM response was found. This could be ascribed to the presence of rheumatoid factor activity in 20 of them. Eight patients who showed a transient rise in IgG antibody between the two dips could be distinguished from the remaining ones by a lower maximum number of IEA+ cells and less severe disease symptoms. The described results suggest that (i) an adequate humoral immune system may prevent symptomatic CMV disease in secondary infections; and (ii) CMV-specific antibodies may be removed from the circulation by antigens present in infected tissues before CMV antigenaemia becomes detectable.

Isolation of highly purified lymphocyte subsets for functional studies by means of an indirect rosette technique

An indirect rosette assay, utilizing ox erythrocytes (RBC) coupled with rabbit anti-mouse IgG and lymphocytes sensitized with monoclonal mouse antibodies against membrane markers, was used for purification of lymphocyte subsets that were functionally intact. Either peripheral blood mononuclear cells (PBMC) or T lymphocytes isolated by sheep RBC rosetting could be used as starting material for obtaining pure T-cell subsets (T4 or T8). The following steps of the method were evaluated: the procedure of coupling rabbit anti-mouse IgG to ox RBC via the CrCl3 method, the experimental conditions for specific rosetting, and the use of Percoll for the separation of rosettes from the non-rosetting cells. Under optimal experimental conditions the recovery of positively selected cells was 45-55% of the cells originally present in the PBMC. The purity of these cells reached a value of more than 95%, whereas the contamination of the depleted fraction was less than 3%. The functional integrity, manifesting itself as proliferation after mitogen stimulation and as regulatory influences on in vitro Ig synthesis, appeared to be unimpaired. The described technique may be applied to the purification of various cell subpopulations for functional studies, provided monoclonal antibodies against membrane antigens are available.