Photoresponsive Hydrogels with Photoswitchable Mechanical Properties Allow Time-Resolved Analysis of Cellular Responses to Matrix Stiffening

As cell function and phenotype can be directed by the mechanical characteristics of the surrounding matrix, hydrogels have become important platforms for cell culture systems, with properties that can be tuned by external stimuli, such as divalent cations, enzymatic treatment, and pH. However, many of these stimuli can directly affect cell behavior, making it difficult to distinguish purely mechanical signaling events. This study reports on the development of a hydrogel that incorporates photoswitchable cross-linkers, which can reversibly alter their stiffness upon irradiation with the appropriate wavelength of light. Furthermore, this study reports the response of bone-marrow-derived mesenchymal stem cells (MSCs) on these hydrogels that were stiffened systematically by irradiation with blue light. The substrates were shown to be noncytotoxic, and crucially MSCs were not affected by blue-light exposure. Time-resolved analysis of cell morphology showed characteristic cell spreading and increased aspect ratios in response to greater substrate stiffness. This hydrogel provides a platform to study mechanosignaling in cells responding to dynamic changes in stiffness, offering a new way to study mechanotransduction signaling pathways and biological processes, with implicit changes to tissue mechanics, such as development, ageing, and fibrosis.

CollAborative care and active surveillance for Screen-Positive EldeRs with subthreshold depression (CASPER): a multicentred randomised controlled trial of clinical effectiveness and cost-effectiveness

BACKGROUND

Efforts to reduce the burden of illness and personal suffering associated with depression in older adults have focused on those with more severe depressive syndromes. Less attention has been paid to those with mild disorders/subthreshold depression, but these patients also suffer significant impairments in their quality of life and level of functioning. There is currently no clear evidence-based guidance regarding treatment for this patient group.

OBJECTIVES

To establish the clinical effectiveness and cost-effectiveness of a low-intensity intervention of collaborative care for primary care older adults who screened positive for subthreshold depression.

DESIGN

A pragmatic, multicentred, two-arm, parallel, individually randomised controlled trial with a qualitative study embedded within the pilot. Randomisation occurred after informed consent and baseline measures were collected.

SETTING

Thirty-two general practitioner (GP) practices in the north of England.

PARTICIPANTS

A total of 705 participants aged ≥ 75 years during the pilot phase and ≥ 65 years during the main trial with subthreshold depression.

INTERVENTIONS

Participants in the intervention group received a low-intensity intervention of collaborative care, which included behavioural activation delivered by a case manager for an average of six sessions over 7-8 weeks, alongside usual GP care. Control-arm participants received only usual GP care.

MAIN OUTCOME MEASURES

The primary outcome measure was a self-reported measure of depression severity, the Patient Health Questionnaire-9 items PHQ-9 score at 4 months post randomisation. Secondary outcome measures included the European Quality of Life-5 Dimensions, Short Form questionnaire-12 items, Patient Health Questionnaire-15 items, Generalised Anxiety Disorder seven-item scale, Connor-Davidson Resilience Scale two-item version, a medication questionnaire and objective data. Participants were followed up for 12 months.

RESULTS

In total, 705 participants were randomised (collaborative care n = 344, usual care n = 361), with 586 participants (83%; collaborative care 76%, usual care 90%) followed up at 4 months and 519 participants (74%; collaborative care 68%, usual care 79%) followed up at 12 months. Attrition was markedly greater in the collaborative care arm. Model estimates at the primary end point of 4 months revealed a statistically significant effect in favour of collaborative care compared with usual care [mean difference 1.31 score points, 95% confidence interval (CI) 0.67 to 1.95 score points; p < 0.001]. The difference equates to a standard effect size of 0.30, for which the trial was powered. Treatment differences measured by the PHQ-9 were maintained at 12 months' follow-up (mean difference 1.33 score points, 95% CI 0.55 to 2.10 score points; p = 0.001). Base-case cost-effectiveness analysis found that the incremental cost-effectiveness ratio was £9633 per quality-adjusted life-year (QALY). On average, participants allocated to collaborative care displayed significantly higher QALYs than those allocated to the control group (annual difference in adjusted QALYs of 0.044, 95% bias-corrected CI 0.015 to 0.072; p = 0.003).

CONCLUSIONS

Collaborative care has been shown to be clinically effective and cost-effective for older adults with subthreshold depression and to reduce the proportion of people who go on to develop case-level depression at 12 months. This intervention could feasibly be delivered in the NHS at an acceptable cost-benefit ratio. Important future work would include investigating the longer-term effect of collaborative care on the CASPER population, which could be conducted by introducing an extension to follow-up, and investigating the impact of collaborative care on managing multimorbidities in people with subthreshold depression.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN02202951.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 8. See the NIHR Journals Library website for further project information.

Abstract PD5-08: Not presented

This abstract was not presented at the symposium.

The second Randomised Evaluation of the Effectiveness, cost-effectiveness and Acceptability of Computerised Therapy (REEACT-2) trial: does the provision of telephone support enhance the effectiveness of computer-delivered cognitive behaviour therapy? A randomised controlled trial

BACKGROUND

Computerised cognitive behaviour therapy (cCBT) is an efficient form of therapy potentially improving access to psychological care. Indirect evidence suggests that the uptake and effectiveness of cCBT can be increased if facilitated by telephone, but this is not routinely offered in the NHS.

OBJECTIVES

To compare the clinical effectiveness and cost-effectiveness of telephone-facilitated free-to-use cCBT [e.g. MoodGYM (National Institute for Mental Health Research, Australian National University, Canberra, ACT, Australia)] with minimally supported cCBT.

DESIGN

This study was a multisite, pragmatic, open, two-arm, parallel-group randomised controlled trial with a concurrent economic evaluation.

SETTING

Participants were recruited from GP practices in Bristol, Manchester, Sheffield, Hull and the north-east of England.

PARTICIPANTS

Potential participants were eligible to participate in the trial if they were adults with depression scoring ≥ 10 on the Patient Health Questionnaire-9 (PHQ-9).

INTERVENTIONS

Participants were randomised using a computer-generated random number sequence to receive minimally supported cCBT or telephone-facilitated cCBT. Participants continued with usual general practitioner care.

MAIN OUTCOME MEASURES

The primary outcome was self-reported symptoms of depression, as assessed by the PHQ-9 at 4 months post randomisation.

SECONDARY OUTCOMES

Secondary outcomes were depression at 12 months and anxiety, somatoform complaints, health utility (as assessed by the European Quality of Life-5 Dimensions questionnaire) and resource use at 4 and 12 months.

RESULTS

Clinical effectiveness: 182 participants were randomised to minimally supported cCBT and 187 participants to telephone-facilitated cCBT. There was a difference in the severity of depression at 4 and 12 months, with lower levels in the telephone-facilitated group. The odds of no longer being depressed (defined as a PHQ-9 score of < 10) at 4 months were twice as high in the telephone-facilitated cCBT group [odds ratio (OR) 2.05, 95% confidence interval (CI) 1.23 to 3.42]. The benefit of telephone-facilitated cCBT was no longer significant at 12 months (OR 1.63, 95% CI 0.98 to 2.71). At 4 months the between-group difference in PHQ-9 scores was 1.9 (95% CI 0.5 to 3.3). At 12 months the results still favoured telephone-facilitated cCBT but were no longer statistically significant, with a difference in PHQ-9 score of 0.9 (95% CI -0.5 to 2.3). When considering the whole follow-up period, telephone-facilitated cCBT was asssociated with significantly lower PHQ-9 scores than minimally supported cCBT (mean difference -1.41, 95% CI -2.63 to -0.17; p = 0.025). There was a significant improvement in anxiety scores over the trial period (between-group difference 1.1, 95% CI 0.1 to 2.3; p = 0.037). In the case of somatic complaints (assessed using the Patient Health Questionnaire-15), there was a borderline statistically significant difference over the trial period (between-group difference 1.1, 95% CI 0.0 to 1.8; p = 0.051). There were gains in quality-adjusted life-years at reduced cost when telephone facilitation was added to MoodGYM. However, the results were subject to uncertainty.

CONCLUSIONS

The results showed short-term benefits from the addition of telephone facilitation to cCBT. The effect was small to moderate and comparable with that of other primary care psychological interventions. Telephone facilitation should be considered when offering cCBT for depression.

LIMITATIONS

Participants' depression was assessed with the PHQ-9, cCBT use was quite low and there was a slightly greater than anticipated loss to follow-up.

FUTURE RESEARCH RECOMMENDATIONS

Improve the acceptability of cCBT and its capacity to address coexisting disorders. Large-scale pragmatic trials of cCBT with bibliotherapy and telephone-based interventions are required.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN55310481.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 89. See the NIHR Journals Library website for further project information.

Gatekeeping access to community mental health teams

Aims and Method

A retrospective survey to explore how consultant psychiatrists, senior house officers and community psychiatric nurses prioritised referrals to four sectorised community mental health teams.

Results

Referral outcomes appeared to be comparable for patients with psychoses, sub-threshold mental health problems and personality disorders. However, differences in the outcomes were apparent for patients with a primary diagnosis of drug/alcohol misuse, as well as for patients with affective disorders and neuroses.

Clinical Implications

It may be necessary to establish clearer, consistent boundaries in order to consolidate services for patients with severe mental health problems.

Using the simplified case mix tool (sCMT) to identify cost in special care dental services to support commissioning

To commission dental services for vulnerable (special care) patient groups effectively, consistently and fairly an evidence base is needed of the costs involved. The simplified Case Mixed Tool (sCMT) can assess treatment mode complexity for these patient groups.

OBJECTIVE

To determine if the sCMT can be used to identify costs of service provision.

CLINICAL SETTING

Patients (n=495) attending the Sussex Community NHS Trust Special Care Dental Service for care were assessed using the sCMT.

MAIN MEASURES

sCMT score and costs (staffing, laboratory fees, etc.) besides patient age, whether a new patient and use of general anaesthetic/intravenous sedation.

METHOD

Statistical analysis (adjusted linear regression modelling) compared sCMT score and costs then sensitivity analyses of the costings to age, being a new patient and sedation use were undertaken. Regression tables were produced to present estimates of service costs.

RESULTS

Costs increased with sCMT total scale and single item values in a predictable manner in all analyses except for 'cooperation'. Costs increased with the use of IV sedation; with each rising level of the sCMT, and with complexity in every sCMT category, except cooperation.

CONCLUSION

Costs increased with increase in complexity of treatment mode as measured by sCMT scores. Measures such as the sCMT can provide predictions of the resource allocations required when commissioning special care dental services.

Preventing depression: Qualitatively examining the benefits of depression-focused iCBT for participants who do not meet clinical thresholds

•First qualitative study on the benefits of iCBT for those who do not meet clinical thresholds•Successful application of cognitive and behavioural strategies reported•Increased insight/awareness and improved self-efficacy reported•The format of online delivery was reported as helpful.•Findings align with previous face-to-face and iCBT treatments.

Inter-rater Reliability of Sonographic Optic Nerve Sheath Diameter Measurements by Emergency Medicine Physicians

OBJECTIVES

To compare the degree of agreement of sonographic optic nerve sheath diameter (ONSD) measurements by ultrasound fellowship-trained and resident emergency medicine (EM) physicians.

METHODS

Ten ultrasound fellowship-trained EM attending physicians from multiple institutions and 51 resident EM physicians at a single residency were enrolled to measure the ONSD using a computerized ruler on five separate still-frame sonograms of adult eyes that included the retrobulbar optic nerve. Descriptive and bivariate statistics for each ultrasound image were calculated to compare median ONSD measurements among groups. Intraclass correlation coefficients (ICCs) were calculated to estimate the inter-rater reliability.

RESULTS

Although the median ONSD measurement of each image did not significantly differ between resident and ultrasound fellowship-trained EM physicians, we found greater variation in agreement of ONSD measurements by resident EM physicians (ICC 0.50; 95% confidence interval 0.25-0.89) than ultrasound fellowship-trained EM physicians (ICC 0.73; 95% confidence interval 0.44-0.96).

CONCLUSIONS

Although both resident and ultrasound fellowship-trained EM physicians showed good inter-rater reliability of ONSD measurements, variation in agreement among ultrasound fellowship-trained EM physicians may be as wide as 0.44, suggesting that even in skilled hands, ultrasound measurement of the ONSD may not be as dependable a screening tool for elevated intracranial pressure as previously suggested in the literature.

Abstract 4690: Hexavalent CD27 agonists show single agent anti-tumor activity and enhanced memory formation in mouse syngeneic tumor models

Tumor necrosis factor receptor superfamily (TNFRSF) proteins are widely expressed by immune and tumor cells highlighting their importance in multiple locations and phases of the anti-tumor immune response. Apogenix has developed a proprietary technology platform for the construction of novel hexavalent TNFRSF agonists (HERA) for the treatment of cancer. HERA fusion proteins comprise a perfect molecular mimic of the TNFSF cytokine structure and are based on dimerization of trivalent single-chain TNFSF receptor-binding domains (scTNFSF-RBD) via a Fc-γ receptor (FcγR) binding deficient immunoglobulin Fc domain. As a result of this molecular design, HERA proteins are capable of clustering six receptors in a spatially well-defined manner. Signaling following treatment with the Apogenix HERA “scTNFSF-RBD-Fc fusion proteins” is entirely independent of secondary crosslinking through FcγRs that is required for many agonistic anti-TNFRSF antibodies. The HERA engineering concept has been successfully translated to TRAIL, GITRL, CD40L, LIGHT and CD27L resulting in agonists that are currently in development. CD27L is a potent co-stimulatory molecule that drives T cell activation and survival through interaction with its receptor (CD27). HERA-CD27L is expressed in CHO suspension cells followed by a lab-scale purification process that results in homogenous aggregate-free protein lots. The purified protein binds its respective target-receptor with high affinity. In vitro, HERA-CD27L was able to bind CD27 expressed on primary human CD4+ and CD8+ T cells. Binding significantly increased T cell expansion following αCD3/αCD28 stimulation and leads to increased expression of OX40 on CD4+ T cells and 4-1BB on CD8+ T cells, respectively. In vivo, a single dose of 10mg/kg HERA-CD27L increases clonal expansion of antigen-specific CD8+ T cells upon immunization with Ovalbumin (Ova) in the mouse OT-1 model with a kinetics leading to peak levels of &gt;25% Ova-specific CD8+ T cells at day 6 after treatment. Anti-tumor efficacy of HERA-CD27 was evaluated in MC38-CEA and CT26 colorectal syngeneic murine tumor models. In both models treatment with HERA-CD27L resulted in a dose dependent inhibition of tumor growth. CT26 tumor bearing mice treated with 1mg/kg HERA-CD27L, twice weekly showed an 85% tumor-growth inhibition (TGI) compared to the control group. A significant TGI of 48% could be observed in the MC38-CEA model upon treatment with 10mg/kg, twice weekly. Analysis of peripheral lymphoid tissues in the MC38-CEA bearing mice could furthermore show that HERA-CD27L treatment is accompanied with enhanced memory formation in both CD4+ & CD8+ T cells. In summary, the data on the hexavalent HERA-CD27L indicate a potent immune cell driven anti tumor efficacy. Therefore, HERA-CD27 agonists could be applied for the treatment of cancer as a single agent or in combination with check-point Inhibitors.

Citation Format: Christian Gieffers, David Richards, Jaromir Sykora, Mauricio Redondo-Müller, Meinolf Thiemann, Christian Merz, Karl Heinonen Heinonen, Viola Marschall, Harald Fricke, Oliver Hill. Hexavalent CD27 agonists show single agent anti-tumor activity and enhanced memory formation in mouse syngeneic tumor models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4690. doi:10.1158/1538-7445.AM2017-4690

PeP-SCOT a health coaching intervention for people in prisons: the development of the intervention protocol

There is a need for an alternative approach for health promotion prisons since previous work has indicated that health education, while improving health knowledge, does not result in behaviour change. Evidence has suggested that a health coaching assists in this regard. However, the question remained whether this approach would be appropriate and possible in prisons? This paper presents the public health strategies used to work in partnership with prison management to address challenges and accept opportunities as a health coaching intervention protocol was developed for oral health and wellbeing in the prison setting.

Spontaneous emission in non-local materials

Light-matter interactions can be strongly modified by the surrounding environment. Here, we report on the first experimental observation of molecular spontaneous emission inside a highly non-local metamaterial based on a plasmonic nanorod assembly. We show that the emission process is dominated not only by the topology of its local effective medium dispersion, but also by the non-local response of the composite, so that metamaterials with different geometric parameters but the same local effective medium properties exhibit different Purcell factors. A record-high enhancement of a decay rate is observed, in agreement with the developed quantitative description of the Purcell effect in a non-local medium. An engineered material non-locality introduces an additional degree of freedom into quantum electrodynamics, enabling new applications in quantum information processing, photochemistry, imaging and sensing with macroscopic composites.

Anthracyclines induce early changes in left ventricular systolic and diastolic function: A single centre study

AIMS

2 dimensional (2D) strain analysis detects subclinical left ventricular (LV) systolic dysfunction. Our aim was to evaluate changes in LV systolic and diastolic function in breast cancer patients early after anthracycline chemotherapy, and to identify predisposing factors.

METHODS AND RESULTS

140 patients were assessed by detailed echocardiography before and within seven days post treatment. LV ejection fraction (LVEF), global longitudinal strain (GLS), strain rate and radial and circumferential strain were assessed. Additionally, left atrial volumes and LV diastolic parameters were evaluated. LVEF although reduced after treatment, remained within the normal range (60±3% vs. 59±3%, p = 0.04). Triplane GLS was significantly reduced after treatment (-20.0±1.6% vs. -19.1±1.8%, p<0.001). Subclinical LV dysfunction (>11% reduction in GLS compared to before therapy) occurred in 22% (29/135). Impaired diastolic function grade significantly increased from 46% to 57% (p<0.001) after treatment. Furthermore, diastolic dysfunction was more common in the subgroup group with reduced systolic GLS compared to those without changes in GLS (30% vs. 11%; p = 0.04). No risk factors or clinical parameters were associated with the development of subclinical LV dysfunction; however the percentage change in early diastolic strain rate and the E velocity were independent predictors of >11% reduction in GLS.

CONCLUSION

Twenty two percent of patients had subclinical LV dysfunction by GLS, whilst none had cardiotoxicity defined by LVEF, demonstrating that GLS is more sensitive for detection of subclinical LV systolic dysfunction immediately after anthracycline therapy. Diastolic dysfunction increased, particularly in the group with reduced GLS, demonstrating the close pathophysiological relationship between systolic and diastolic function.

Abstract A83: Hexavalent agonists targeting co-stimulatory receptors of the tumor necrosis factor superfamily

Tumor necrosis factor receptor superfamily (TNFRSF) proteins are widely expressed by immune and tumor cells highlighting their importance in multiple locations and phases of the anti-tumor immune response. Whereas agonistic stimulation of TRAIL-Receptor-1 or -2 can directly induce apoptosis in tumor cells, signaling through many TNFRSF members, such as CD40, CD27, OX40, HVEM, GITR and 4-1BB, results in co-stimulation of immune cells. Therefore, agonistic stimulation of certain members of the TNFRSF is considered to have a positive impact on immune-based therapeutic concepts in clinical oncology. Apogenix has developed a proprietary technology platform for the construction of novel hexavalent TNFRSF agonists (HERA) for the treatment of cancer. HERA fusion proteins are based on a perfect molecular mimic of the TNFSF cytokine structure. The HERA core unit consists of one single polypeptide chain comprising the three receptor-binding domain-forming subsequences (TNFSF-protomers). These single-chain TNFSF receptor-binding domains (scTNFSF-RBD) preserve the structural organization of the trimeric natural TNFSF cytokine and can be utilized to engineer fully human fusion-proteins in a modular manner. Fusing an IgG1 Fc-domain as a dimerization scaffold to the C-terminus of a scTNFSF-RBD creates a hexavalent agonist from two trivalent scTNFSF-RBDs. As a result of this molecular design, each molecule is capable of clustering six receptors in a spatially well-defined manner in close proximity to each other. Therefore, signaling following treatment with the Apogenix HERA scTNFSF-RBD-Fc fusion proteins in vivo is independent of secondary clustering through Fc-γ receptors that is required for many agonistic anti-TNFRSF antibodies (e.g., anti-TRAIL-R2 or anti-CD40). The described HERA engineering concept has been successfully translated to TRAIL, CD40L, LIGHT and CD27L resulting in hexavalent agonists suitable for further development. CD27-Ligand is a potent co-stimulatory molecule that drives T-cell activation and survival through interaction with its receptor (CD27). Here we show in vitro and in vivo data for APG1293 (scCD27L-RBD-Fc), a hexavalent CD27 agonist. APG1293 was expressed in CHO suspension cells followed by a lab-scale purification process including affinity chromatography and SEC-based polishing, resulting in homogenous aggregate-free protein lots. The purified protein binds its respective target-receptor with high affinity. In vivo stability/PK studies have been performed in addition to in vitro experiments with primary human and mouse lymphoid and myeloid cell populations. Specifically, APG1293 was able to bind CD27 expressed on primary human CD4+ and CD8+ T cells and importantly, binding significantly increased T-cell expansion following activation. In vivo the efficacy of APG1293 was evaluated in the colorectal syngeneic murine tumor models MC38-CEA and CT26. In both models APG1293 treatment resulted in a dose dependent tumor growth inhibition. In summary, the data on the hexavalent APG1293 indicate a potent immune cell driven anti tumor efficacy. Therefore, APG1293 could be applied as a single agent or in combination with check-point inhibitors.

Citation Format: Christian Gieffers, Christian Merz, David Richards, Mauricio Redondo, Viola Marschall, Jaromir Sykora, Meinolf Thiemann, Harald Fricke, Oliver Hill. Hexavalent agonists targeting co-stimulatory receptors of the tumor necrosis factor superfamily. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2016 Oct 20-23; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2017;5(3 Suppl):Abstract nr A83.

Incidence, Time Course and Predictors of Impairments Relating to Caring for the Profoundly Affected arm After Stroke: A Systematic Review

BACKGROUND AND PURPOSE

A significant number of stroke survivors will not recover the use of their affected arm. A proportion will experience pain, stiffness and difficulty with basic care activities. The purpose of the review was to identify predictors of difficulty caring for the profoundly affected arm and establish the incidence and time-course of the related impairments of pain, spasticity and contracture.

METHOD

Data sources: Databases (PubMED, MEDLINE, AMED, EMBASE, CINAHL and the Cochrane Controlled Trials Register) were searched from inception to December 2013. Additional studies were identified from citation tracking.

REVIEW METHODS

Independent reviewers used pre-defined criteria to identify eligible studies. Quality assessment and risk of bias were assessed using the McMasters Assessment Tool. A narrative evidence synthesis was performed.

RESULTS

Thirty-nine articles reporting 34 studies were included. No studies formally measured difficulty caring for the arm, but related impairments were common. Incidence of spasticity in those with weakness ranged from 33% to 78%, shoulder pain affected 22% to 90% and contracture was present in at least 50%. Spasticity and pain appear within 1 week of stroke, and contracture within two weeks. Impairments continued to develop over at least 3-6 months. The most frequent predictors of spasticity and contracture were weakness and reduced motor control, and the risk of pain is most commonly predicted by reduced sensation, shoulder subluxation, weakness and stroke severity.

DISCUSSION

There is no published evidence on predicting the likelihood of difficulty caring for the arm following stroke. However, the related impairments of spasticity, pain and contracture are common. Given the time-course of development, clinicians may need not only to intervene early but also be prepared to act over a longer time period. Further research is needed to examine difficulty caring for the arm and the relationship with associated impairments to enable researchers and clinicians to develop targeted interventions. © 2015 The Authors. Physiotheraphy Research International Published by John Wiley & Sons Ltd.

Adverse diastolic remodeling after reperfused ST-elevation myocardial infarction: An important prognostic indicator

OBJECTIVES

We sought to determine the relationship of adverse diastolic remodeling (ie, worsening diastolic or persistent restrictive filling) with infarct scar characteristics, and to evaluate its prognostic value after ST-segment elevation myocardial infarction (STEMI).

BACKGROUND

Severe diastolic dysfunction (restrictive filling) has known prognostic value post STEMI. However, ongoing left ventricular (LV) remodeling post STEMI may alter diastolic function even if less severe.

METHODS AND RESULTS

There were 218 prospectively recruited STEMI patients with serial echocardiograms (transthoracic echocardiography) and cardiac magnetic resonance imaging (CMR) performed, at a median of 4 days (early) and 55 days (follow-up). LV ejection fraction and infarct characteristics were assessed by CMR, and comprehensive diastolic function assessment including a diastolic grade was evaluated on transthoracic echocardiography. 'Adverse diastolic remodeling' occurred if diastolic function grade either worsened (≥1 grade) between early and follow-up imaging, or remained as persistent restrictive filling at follow-up. Follow-up infarct scar size (IS) predicted adverse diastolic remodeling (area under the curve 0.86) and persistent restrictive filling (area under the curve 0.89). The primary endpoint of major adverse cardiovascular events (MACE) occurred in 48 patients during follow-up (mean, 710±79 days). Kaplan-Meier analysis showed that adverse diastolic remodeling (n=50) and persistent restrictive filling alone (n=33) were significant predictors of MACE (both P<.001). Multivariate Cox analysis, when adjusted for TIMI risk score and CMR IS, microvascular obstruction, and LV ejection fraction, showed adverse diastolic remodeling (HR 3.79, P<.001) was an independent predictor of MACE, as was persistent restrictive filling alone (HR 2.61, P=.019).

CONCLUSIONS

Larger IS is associated with adverse diastolic remodeling. Following STEMI, adverse diastolic remodeling is a powerful prognostic marker, and identifies a larger group of 'at-risk' patients, than does persistent restrictive filling alone.

Alterations in regional myocardial deformation assessed by strain imaging in cardiac amyloidosis

BACKGROUND

Cardiac amyloidosis results in increased left ventricular (LV) wall thickness and diastolic dysfunction (DD). Strain measurements using velocity vector imaging (VVI) may further characterize myocardial dysfunction.

METHODS

A total of 43 AL amyloidosis patients were compared to age-matched normals and hypertensive patients (HT). Subgroup analysis within the amyloid group was performed based on LV wall thickness (≤14 mm, >14 mm) and diastolic dysfunction (DD) (Group 1: normal and impaired relaxation, Group 2: pseudonormal, Group 3: restrictive). LV strain (longitudinal, circumferential, and radial strain (S) and strain rate [Sr]) were measured using velocity vector imaging (VVI).

RESULTS

Increased LV wall thickness and DD were observed in the amyloid group. Global longitudinal (-13.9±4.1% vs -16.7±3.8%; P=.002) and radial (27.4±13.4% vs 38.8±15.7%; P<.001) strain were lower in the amyloid group vs normal controls, while circumferential strain was similar. Segmental analysis demonstrated reduced mid- and basal segmental strain with relative sparing of apical segments in the amyloid group. Reduced longitudinal and radial strain, with preserved circumferential strain, were observed in patients with wall thickness >14 mm; however, circumferential strain was also altered when severe DD (restrictive filling) was present.

CONCLUSION

Reduction in longitudinal and radial S and Sr was evident using VVI strain analysis in amyloidosis, with segmental heterogeneity in longitudinal S. There was relative preservation of circumferential strain, which was reduced only in patients with severe DD.

A critical realist rationale for using a combination of quantitative and qualitative methods

Although using a combination of quantitative and qualitative approaches is widely advocated, there is considerable scope for confusion due to the complex ontological and epistemological issues that need to be resolved. This paper examines some of the issues that may arise when the methods are combined. Three distinct standpoints with regard to using mixed method approaches are highlighted: a methodological purist position, a pragmatic standpoint and an anti-conflationist position. It is suggest that an anti-conflationist approach that is underpinned by the philosophy of critical realism is compatible with all three of the purposes of methodological triangulation identified by Risjord and his co-authors (Risjord et al., 2001, 2002) and that adopting a critical realist perspective may circumvent many of the problems that are associated with paradigm ‘switching’. The case for adopting a critical realist framework is illustrated by a case study, in which a combination of quantitative and qualitative methods was used to explore how and why gatekeeping decisions emerge at the interface between primary care and community mental health teams.