Staging cardiac damage in aortic valve disease: one size fits all?

Background

Nowadays, in patients with aortic regurgitation (AR), aortic valve surgery is indicated when severe and symptomatic or those with depressed LVEF. However, clinical outcomes of patients with significant aortic regurgitation are not influenced by these factors only. Recently, a new staging system for severe aortic stenosis has been proposed by Généreux on the basis of the extent of anatomic and functional cardiac damage. If this model could be applicable to an unselected significant AR population has not been tested.

Purpose

The aim of our study was to evaluate the prevalence of the different stages of extra-aortic valvular cardiac damage by the application of Généreux staging and its impact on prognosis in a large, real world cohort of significant AR patients.

Methods

This study retrospectively analysed the clinical, Doppler echocardiographic and outcome data in patients with grade III or greater AR between January 2014 and September 2019. According to the extent of cardiac damage on echocardiography, patients were classified as Stage 0 (no cardiac damage), Stage 1 (left ventricular damage), Stage 2 (mitral valve or left atrial damage), Stage 3 (tricuspid valve or pulmonary artery vasculature damage) or Stage 4 (right ventricular damage). Exclusion criteria were severe aortic stenosis and previous valve repair or replacement. The primary end-point was all-cause mortality.

Results

A total of 572 patients, aged 70.1±13.9 years, 294 (51.3%) men were enrolled. One third of patients were in NYHA I. Based on the proposed classification, 82 patients (14.3%) were classified in stage 0, 130 (22.7%) in stage 1, 276 (48.2%) in stage 2, 68 (11.8%) in stage 3 and 17 (3.0%) in stage 4. Median follow-up time was 3.3±1.9 years. There was a progressive increase in mortality rates according to staging: 8.5% in stage 0, 10.8% in stage 1, 24.9% in stage 2, 42.6% in stage 3 and 52.9% in stage 4 (p<0.001). On multivariable analysis, the extent of cardiac damage was independently associated with excess mortality (HR 1.69, 95% CI 1.29 to 2.21)

Conclusion

Our study demonstrated that this new staging system studied for aortic stenosis also provides increased prognostic value to patients with significant aortic regurgitation. This staging system can be helpful to identify the degree of extra-aortic valvular cardiac damage and to optimize the time of valvular intervention. Further prospective studies are needed to confirm the benefit of the applicability of this model in clinical practice.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Centro Hospitalar Vila Nova de Gaia / Espinho Distribution of stages of cardiac damageSurvival analysis according to stage

Prognostic impact of coronary artery disease severity and revascularization in TAVI patients

Background

Coronary artery disease (CAD) is highly prevalent in patients with severe aortic stenosis. In patients who undergo surgical aortic valve replacement, the presence of CAD and the need for CABG adversely influences short- and long-term outcomes. However, the impact of concomitant CAD and its revascularization in patients undergoing transcatheter aortic valve implantation (TAVI) is still a matter of debate.

Purpose

The aim of this study was to evaluate the prognostic impact of CAD severity in 1-year all-cause mortality of patients undergoing TAVI and whether prior complete or incomplete reasonable revascularization can improve prognosis after TAVI.

Methods and results

Retrospective analysis of a total of 575 patients (51,3% female, mean age 79,7±7,7 years) who underwent TAVI from August 2007 to November 2018. 50,3% of patients had significant CAD (at least one stenosis >50%) which 54,2% of these had history of prior revascularization (64,8% complete or incomplete reasonable revascularization and 35,2% incomplete revascularization).

Pre-TAVI CAD severity was defined by the SYNTAX Score (SS) and reasonable revascularization by the residual SYNTAX Score (rSS). Patients without history of revascularization were stratified into 3 groups: no CAD (SS=0); nonsevere CAD (SS between 1 and 22); and severe CAD (SS ≥23); Patients who had undergone revascularization prior to TAVI were separated into 2 categories based on their residual SS: complete or incomplete reasonable revascularization (rSS<8) and incomplete revascularization (rSS≥8). The primary end point was an all-cause mortality. 1 year, patients with severe CAD had significantly higher rates of mortality (no CAD: 9,8%, nonsevere CAD: 12,6%, severe CAD: 38,9%; P=0.001) without significant differences between patients with no CAD and nonsevere CAD (p=1,00). Patients with high rSS had significantly higher rates of mortality comparing to no CAD or rSS<8 (no CAD: 9,8%, rSS<8: 8,6%; rSS≥8: 28,0%, p=0.001).

Conclusions

In our study, only the presence of severe CAD (SS≥23) prior to TAVI was associated with increased 1-year all-cause mortality. In patients with previous history of revascularization, a complete/reasonable revascularization (lower rSS) was associated with lower long-term mortality, which may attenuate the association of severe CAD and mortality and therefore improve the prognosis of these patients.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Centro Hospitalar Vila Nova de Gaia / Espinho Figure 1. Prognostic Impact of CAD severityFigure 2. Prognostic Impact of Revascularization

Feasibility of coronary angiography after TAVR

Background

The prevalence of coronary artery disease (CAD) is high among patients with severe aortic stenosis who undergo transcatheter aortic valve replacement (TAVR).

Indications for TAVR are now expanding to younger and lower risk patients. During their lifetime, these patients will be at risk of developing CAD and it is expected an increase in coronary angiography and percutaneous coronary intervention (PCI). Aortic prosthesis, particularly if in supra-annular position, may pose important technical difficulties in coronary re-engagement after TAVR.

Purpose

To evaluate the feasibility to reengage the coronary ostia after TAVR, describe complications and compare technical differences between coronary procedures performed before and after TAVR.

Methods

Retrospective analysis of 714 patients submitted to TAVR from August 2007 to December 2019. Patients who needed coronary angiography after TAVR were selected.

The primary endpoint was the rate of successful coronary ostia cannulation after TAVR, defined by the possibility to selectively cannulate and inject both coronary ostia.

Secondary endpoint was complications associated with coronary catheterization after TAVR.

Results

Among 714 patients, 25 (3.5%) patients were submitted to a total of 28 coronary angiography after TAVR. 14 patients were male (56%), mean age 78.2±6.2 years and 9 (36%) had history of previous coronary revascularization.

From the 28 coronary angiographies (balloon-expandable Edwards-Sapien n=11, 44%; self-expandable CoreValve n=10, 40%; Portico n=2, 8%; Symetis n=2, 8%), 25 (89%) met the primary endpoint. Only three was semiselective (Symetis, CoreValve Evolut R and CoreValve TAVR in TAVR), with impossibility to cannulate both coronary arteries, right coronary artery and left coronary artery, respectively. 13 (46%) patients had also indication for PCI and all were successfully performed (Edwards-Sapien n=4, 31%; CoreValve n=6, 46%; Portico n=2, 15%; Symetis n=1, 8%). The main indications for coronary angiography was chronic coronary syndrome (n=12, 43%) and acute coronary syndrome without ST segment elevation (n=7, 25%). Circumflex artery was the most frequently treated vessel (n=6), followed by left anterior descending artery (n=4), right coronary artery (n=3) and left main (n=2).

There were no complications reported during or post-procedure. Comparing coronary angiographies before and after TAVR, there were no significant differences regarding arterial access site, catheter diameter, fluoroscopy time and quantity of contrast used in coronary angiography.

Conclusion

Although the need for coronary angiography was rare in patients after TAVR, selective diagnostic coronary angiographies were possible in 89% (25/28) and PCI was feasible in all patients in whom it was indicated, without any reported complications.

Further prospective studies are needed to confirm the great feasibility of performing coronary angiography after TAVR.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Centro Hospitalar Vila Nova de Gaia / Espinho

Assessment of Tau Pathology as Measured by 18F-THK5317 and 18F-Flortaucipir PET and Their Relation to Brain Atrophy and Cognition in Alzheimer's Disease

BACKGROUND

In Alzheimer's disease (AD), the abnormal aggregation of hyperphosphorylated tau leads to synaptic dysfunction and neurodegeneration. Recently developed tau PET imaging tracers are candidate biomarkers for diagnosis and staging of AD.

OBJECTIVE

We aimed to investigate the discriminative ability of 18F-THK5317 and 18F-flortaucipir tracers and brain atrophy at different stages of AD, and their respective associations with cognition.

METHODS

Two cohorts, each including 29 participants (healthy controls [HC], prodromal AD, and AD dementia patients), underwent 18F-THK5317 or 18F-flortaucipir PET, T1-weighted MRI, and neuropsychological assessment. For each subject, we quantified regional 18F-THK5317 and 18F-flortaucipir uptake within six bilateral and two composite regions of interest. We assessed global brain atrophy for each individual by quantifying the brain volume index, a measure of brain volume-to-cerebrospinal fluid ratio. We then quantified the discriminative ability of regional 18F-THK5317, 18F-flortaucipir, and brain volume index between diagnostic groups, and their associations with cognition in patients.

RESULTS

Both 18F-THK5317 and 18F-flortaucipir outperformed global brain atrophy in discriminating between HC and both prodromal AD and AD dementia groups. 18F-THK5317 provided the highest discriminative ability between HC and prodromal AD groups. 18F-flortaucipir performed best at discriminating between prodromal and dementia stages of AD. Across all patients, both tau tracers were predictive of RAVL learning, but only 18F-flortaucipir predicted MMSE.

CONCLUSION

Our results warrant further in vivo head-to-head and antemortem-postmortem evaluations. These validation studies are needed to select tracers with high clinical validity as biomarkers for early diagnosis, prognosis, and disease staging, which will facilitate their incorporation in clinical practice and therapeutic trials.

The Cognitive Connectome in Healthy Aging

Objectives: Cognitive aging has been extensively investigated using both univariate and multivariate analyses. Sophisticated multivariate approaches such as graph theory could potentially capture unknown complex associations between multiple cognitive variables. The aim of this study was to assess whether cognition is organized into a structure that could be called the “cognitive connectome,” and whether such connectome differs between age groups.

Methods: A total of 334 cognitively unimpaired individuals were stratified into early-middle-age (37–50 years, n = 110), late-middle-age (51–64 years, n = 106), and elderly (65–78 years, n = 118) groups. We built cognitive networks from 47 cognitive variables for each age group using graph theory and compared the groups using different global and nodal graph measures.

Results: We identified a cognitive connectome characterized by five modules: verbal memory, visual memory—visuospatial abilities, procedural memory, executive—premotor functions, and processing speed. The elderly group showed reduced transitivity and average strength as well as increased global efficiency compared with the early-middle-age group. The late-middle-age group showed reduced global and local efficiency and modularity compared with the early-middle-age group. Nodal analyses showed the important role of executive functions and processing speed in explaining the differences between age groups.

Conclusions: We identified a cognitive connectome that is rather stable during aging in cognitively healthy individuals, with the observed differences highlighting the important role of executive functions and processing speed. We translated the connectome concept from the neuroimaging field to cognitive data, demonstrating its potential to advance our understanding of the complexity of cognitive aging.

Cerebrovascular disease, neurodegeneration, and clinical phenotype in dementia with Lewy bodies

We investigated whether cerebrovascular disease contributes to neurodegeneration and clinical phenotype in dementia with Lewy bodies (DLB). Regional cortical thickness and subcortical gray matter volumes were estimated from structural magnetic resonance imaging (MRI) in 165 DLB patients. Cortical and subcortical infarcts were recorded and white matter hyperintensities (WMHs) were assessed. Subcortical only infarcts were more frequent (13.3%) than cortical only infarcts (3.1%) or both subcortical and cortical infarcts (2.4%). Infarcts, irrespective of type, were associated with WMHs. A higher WMH volume was associated with thinner orbitofrontal, retrosplenial, and posterior cingulate cortices, smaller thalamus and pallidum, and larger caudate volume. A higher WMH volume was associated with the presence of visual hallucinations and lower global cognitive performance, and tended to be associated with the absence of probable rapid eye movement sleep behavior disorder. Presence of infarcts was associated with the absence of parkinsonism. We conclude that cerebrovascular disease is associated with gray matter neurodegeneration in patients with probable DLB, which may have implications for the multifactorial treatment of probable DLB.

The interplay between gray matter and white matter neurodegeneration in subjective cognitive decline

Aims: To investigate the interplay between gray matter (GM) and white matter (WM) neurodegeneration in subjective cognitive decline (SCD), including thickness across the whole cortical mantle, hippocampal volume, and integrity across the whole WM.

Methods: We included 225 cognitively unimpaired individuals from a community-based cohort. Subjective cognitive complaints were assessed through 9 questions covering amnestic and non-amnestic cognitive domains. In our cohort, 123 individuals endorsed from one to six subjective cognitive complaints (i.e. they fulfilled the diagnostic criteria for SCD), while 102 individuals reported zero complaints. GM neurodegeneration was assessed through measures of cortical thickness across the whole mantle and hippocampal volume. WM neurodegeneration was assessed through measures of mean diffusivity (MD) across the whole WM skeleton. Mediation analysis and multiple linear regression were conducted to investigate the interplay between the measures of GM and WM neurodegeneration.

Results: A higher number of complaints was associated with reduced hippocampal volume, cortical thinning in several frontal and temporal areas and the insula, and higher MD across the WM skeleton, with a tendency to spare the occipital lobe. SCD-related cortical thinning and increased MD were associated with each other and jointly contributed to complaints, but the contribution of cortical thinning to the number of complaints was stronger.

Conclusions: Neurodegeneration processes affecting the GM and WM seem to be associated with each other in SCD and include brain areas other than those typically targeted by Alzheimer’s disease. Our findings suggest that SCD may be a sensitive behavioral marker of heterogeneous brain pathologies in individuals recruited from the community.

Teleneurology in Parkinson's disease: A step-by-step video guide

BACKGROUND

The COVID-19 pandemic forced the implementation of social distancing and circulation restrictions. This affected all aspects of society including health care. In the field of chronic neurological disorders such as Parkinson's disease (PD), teleneurology is employed in scenarios where face-to-face interactions are not possible. A growing number of clinicians and institutions are turning to teleneurology in order to providing medical care.

AIMS OF THE ARTICLE

In this manuscript, we present a practical, 'how we do it in real life', example of a teleneurology appointment with a person with PD (PwP).

METHODS

We elaborated a step-by-step approach of the main aspects of a consultation with a PwP and provide video illustration.

RESULTS

The key aspects of a teleneurology appointment were separated into: (1) In the office, before the appointment; (2) History taking; (3) Examination; and (4) Finishing up.

CONCLUSIONS

We discuss the strengths and weaknesses of this approach and provide our experience in overcoming commonly encountered difficulties.

Cerebrovascular Disease and Depressive Symptomatology in Individuals With Subjective Cognitive Decline: A Community-Based Study

Subjective cognitive decline (SCD) may be the first sign of Alzheimer's disease (AD), but it can also reflect other pathologies such as cerebrovascular disease or conditions like depressive symptomatology. The role of depressive symptomatology in SCD is controversial. We investigated the association between depressive symptomatology, cerebrovascular disease, and SCD. We recruited 225 cognitively unimpaired individuals from a prospective community-based study [mean age (SD) = 54.64 (10.18); age range 35-77 years; 55% women; 123 individuals with one or more subjective cognitive complaints, 102 individuals with zero complaints]. SCD was assessed with a scale of 9 memory and non-memory subjective complaints. Depressive symptomatology was assessed with established questionnaires. Cerebrovascular disease was assessed with magnetic resonance imaging markers of white matter signal abnormalities (WMSA) and mean diffusivity (MD). We combined correlation, multiple regression, and mediation analyses to investigate the association between depressive symptomatology, cerebrovascular disease, and SCD. We found that SCD was associated with more cerebrovascular disease, older age, and increased depressive symptomatology. In turn, depressive symptomatology was not associated with cerebrovascular disease. Variability in MD was mediated by WMSA burden, presumably reflecting cerebrovascular disease. We conclude that, in our community-based cohort, depressive symptomatology is associated with SCD but not with cerebrovascular disease. In addition, depressive symptomatology did not influence the association between cerebrovascular disease and SCD. We suggest that therapeutic interventions for depressive symptomatology could alleviate the psychological burden of negative emotions in people with SCD, and intervening on vascular risk factors to reduce cerebrovascular disease should be tested as an opportunity to minimize neurodegeneration in SCD individuals from the community.

Association Between Amygdala Volume and Trajectories of Neuropsychiatric Symptoms in Alzheimer's Disease and Dementia With Lewy Bodies

Introduction: The amygdala is implicated in psychiatric illness. Even as the amygdala undergoes significant atrophy in mild dementia, amygdala volume is underexplored as a risk factor for neuropsychiatric symptoms (NPS).

Objective: To analyze the association between baseline amygdala volume and the longitudinal trajectories of NPS and cognitive decline in Alzheimer's disease (AD) and dementia with Lewy bodies (DLB) over 5 years.

Methods: Eighty-nine patients with mild dementia were included (AD = 55; DLB = 34). Amygdala volume was segmented from structural magnetic resonance images (sMRI) using a semi-automatic method (Freesurfer 6.0) and normalized by intracranial volumes. The intracranial volume-normalized amygdala was used as a predictor of the Neuropsychiatric Inventory (NPI) total score, ordinal NPI item scores (0 = absence of symptoms, 1–3 = mild symptoms, ≥4 = clinically relevant symptoms), and Mini-Mental State Examination (MMSE) as measured annually over 5 years using gamma, ordinal, and linear mixed-effects models, respectively. The models were adjusted for demographic variables, diagnosis, center of sMRI acquisition, and cognitive performance. Multiple testing-corrected p-values (q-values) are reported.

Results: Larger intracranial volume-normalized amygdala was associated with less agitation/aggression (odds ratio (OR) = 0.62 [0.43, 0.90], p = 0.011, q = 0.038) and less MMSE decline per year (fixed effect = 0.70, [0.29, 1.03], p = 0.001, q = 0.010) but more depression (OR = 1.49 [1.09, 2.04], p = 0.013, q = 0.040).

Conclusions: Greater amygdala volume in mild dementia is associated with lower odds of developing agitation/aggression, but higher odds of developing depression symptoms during the 5-year study period.

Functional Connectivity and Compensation of Phonemic Fluency in Aging

Neural compensatory mechanisms associated with broad cognitive abilities have been studied. However, those associated with specific cognitive subdomains (e.g., verbal fluency) remain to be investigated in healthy aging. Here, we delineate: (a) neural substrates of verbal (phonemic) fluency, and (b) compensatory mechanisms mediating the association between these neural substrates and phonemic fluency. We analyzed resting-state functional magnetic resonance imaging from 133 right-handed, cognitively normal individuals who underwent the Controlled Oral Word Association Test (COWAT) to record their phonemic fluency. We evaluated functional connectivity in an established and extended language network comprising Wernicke, Broca, thalamic and anti-correlated modules. (a) We conducted voxel-wise multiple linear regression to identify the brain areas associated with phonemic fluency. (b) We used mediation effects of cognitive reserve, measured by the Wechsler Adult Intelligence Scale—Information subtest, upon the association between functional connectivity and phonemic fluency tested to investigate compensation. We found that: (a) Greater functional connectivity between the Wernicke module and brain areas within the anti-correlated module was associated with better performance in phonemic fluency, (b) Cognitive reserve was an unlikely mediator in younger adults. In contrast, cognitive reserve was a partial mediator of the association between functional connectivity and phonemic fluency in older adults, likely representing compensation to counter the effect of aging. We conclude that in healthy aging, higher performance in phonemic fluency at older ages could be attributed to greater functional connectivity partially facilitated by higher cognitive reserve, presumably reflecting compensatory mechanisms to minimize the effect of aging.

Inter-Cohort Validation of SuStaIn Model for Alzheimer's Disease

Alzheimer’s disease (AD) is a neurodegenerative disorder which spans several years from preclinical manifestations to dementia. In recent years, interest in the application of machine learning (ML) algorithms to personalized medicine has grown considerably, and a major challenge that such models face is the transferability from the research settings to clinical practice. The objective of this work was to demonstrate the transferability of the Subtype and Stage Inference (SuStaIn) model from well-characterized research data set, employed as training set, to independent less-structured and heterogeneous test sets representative of the clinical setting. The training set was composed of MRI data of 1043 subjects from the Alzheimer’s disease Neuroimaging Initiative (ADNI), and the test set was composed of data from 767 subjects from OASIS, Pharma-Cog, and ViTA clinical datasets. Both sets included subjects covering the entire spectrum of AD, and for both sets volumes of relevant brain regions were derived from T1-3D MRI scans processed with Freesurfer v5.3 cross-sectional stream. In order to assess the predictive value of the model, subpopulations of subjects with stable mild cognitive impairment (MCI) and MCIs that progressed to AD dementia (pMCI) were identified in both sets. SuStaIn identified three disease subtypes, of which the most prevalent corresponded to the typical atrophy pattern of AD. The other SuStaIn subtypes exhibited similarities with the previously defined hippocampal sparing and limbic predominant atrophy patterns of AD. Subject subtyping proved to be consistent in time for all cohorts and the staging provided by the model was correlated with cognitive performance. Classification of subjects on the basis of a combination of SuStaIn subtype and stage, mini mental state examination and amyloid-β_1-42 cerebrospinal fluid concentration was proven to predict conversion from MCI to AD dementia on par with other novel statistical algorithms, with ROC curves that were not statistically different for the training and test sets and with area under curve respectively equal to 0.77 and 0.76. This study proves the transferability of a SuStaIn model for AD from research data to less-structured clinical cohorts, and indicates transferability to the clinical setting.

Cortical Networks Underpinning Compensation of Verbal Fluency in Normal Aging

Elucidating compensatory mechanisms underpinning phonemic fluency (PF) may help to minimize its decline due to normal aging or neurodegenerative diseases. We investigated cortical brain networks potentially underpinning compensation of age-related differences in PF. Using graph theory, we constructed networks from measures of thickness for PF, semantic, and executive–visuospatial cortical networks. A total of 267 cognitively healthy individuals were divided into younger age (YA, 38–58 years) and older age (OA, 59–79 years) groups with low performance (LP) and high performance (HP) in PF: YA-LP, YA-HP, OA-LP, OA-HP. We found that the same pattern of reduced efficiency and increased transitivity was associated with both HP (compensation) and OA (aberrant network organization) in the PF and semantic cortical networks. When compared with the OA-LP group, the higher PF performance in the OA-HP group was associated with more segregated PF and semantic cortical networks, greater participation of frontal nodes, and stronger correlations within the PF cortical network. We conclude that more segregated cortical networks with strong involvement of frontal nodes seemed to allow older adults to maintain their high PF performance. Nodal analyses and measures of strength were helpful to disentangle compensation from the aberrant network organization associated with OA.

Brain Atrophy Subtypes and the ATN Classification Scheme in Alzheimer's Disease

INTRODUCTION

We investigated the association between atrophy subtypes of Alzheimer's disease (AD), the ATN classification scheme, and key demographic and clinical factors in 2 cohorts with different source characteristics (a highly selective research-oriented cohort, the Alzheimer's Disease Neuroimaging Initiative [ADNI]; and a naturalistic heterogeneous clinically oriented cohort, Karolinska Imaging Dementia Study [KIDS]).

METHODS

A total of 382 AD patients were included. Factorial analysis of mixed data was used to investigate associations between AD subtypes based on brain atrophy patterns, ATN profiles based on cerebrospinal fluid biomarkers, and age, sex, Mini Mental State Examination (MMSE), cerebrovascular disease (burden of white matter signal abnormalities, WMSAs), and APOE genotype.

RESULTS

Older patients with high WMSA burden, belonging to the typical AD subtype and showing A+T+N+ or A+T+N- profiles clustered together and were mainly from ADNI. Younger patients with low WMSA burden, limbic-predominant or minimal atrophy AD subtypes, and A+T-N- or A+T-N+ profiles clustered together and were mainly from KIDS. APOE ε4 carriers more frequently showed the A+T-N- and A+T+N- profiles.

CONCLUSIONS

Our findings align with the recent framework for biological subtypes of AD: the combination of risk factors, protective factors, and brain pathologies determines belonging of AD patients to distinct subtypes.

General practitioners' attitude toward early and pre-dementia diagnosis of AD in five European countries-A MOPEAD project survey

INTRODUCTION

General practitioners (GPs) play a key role in early identification of dementia, yet diagnosis is often missed or delayed in primary care. As part of the multinational Models of Patient Engagement for Alzheimer's Disease project, we assess GPs' attitude toward early and pre-dementia diagnosis of AD and explore barriers to early diagnosis.

METHODS

Our survey covered general attitude toward early diagnosis, diagnostic procedures, resources, and opinion on present and future treatment options across five European countries.

RESULTS

In total 343 GPs completed the survey; 74% of GPs indicated that an early diagnosis is valuable. There were country-specific differences in GPs' perceptions of reimbursement and time available for the patient. If a drug were available to slow down the progression of AD, 59% of the GPs would change their implementation of early diagnosis.

DISCUSSION

Our findings provide insight into GPs' attitudes by exploring differences in perception and management of early diagnosis.

Comparing different approaches for operationalizing subjective cognitive decline: impact on syndromic and biomarker profiles

Subjective cognitive decline (SCD) has been proposed as a risk factor for future cognitive decline and dementia. Given the heterogeneity of SCD and the lack of consensus about how to classify this condition, different operationalization approaches still need to be compared. In this study, we used the same sample of individuals to compare  different SCD operationalization approaches. We included 399 cognitively healthy individuals from a community-based cohort. SCD was assessed through nine questions about memory and non-memory subjective complaints. We applied four approaches to operationalize SCD: two hypothesis-driven approaches and two data-driven approaches. We characterized the resulting groups from each operationalization approach using multivariate methods on comprehensive demographic, clinical, cognitive, and neuroimaging data. We identified two main phenotypes: an amnestic phenotype characterized by an Alzheimer's Disease (AD) signature pattern of brain atrophy; and an anomic phenotype, which was mainly related to cerebrovascular pathology. Furthermore, language complaints other than naming helped to identify a subgroup with subclinical cognitive impairment and difficulties in activities of daily living. This subgroup also showed an AD signature pattern of atrophy. The identification of SCD phenotypes, characterized by different syndromic and biomarker profiles, varies depending on the operationalization approach used. In this study we discuss how these findings may be used in clinical practice and research.

Data-driven FDG-PET subtypes of Alzheimer's disease-related neurodegeneration

BACKGROUND

Previous research has described distinct subtypes of Alzheimer's disease (AD) based on the differences in regional patterns of brain atrophy on MRI. We conducted a data-driven exploration of distinct AD neurodegeneration subtypes using FDG-PET as a sensitive molecular imaging marker of neurodegenerative processes.

METHODS

Hierarchical clustering of voxel-wise FDG-PET data from 177 amyloid-positive patients with AD dementia enrolled in the Alzheimer's Disease Neuroimaging Initiative (ADNI) was used to identify distinct hypometabolic subtypes of AD, which were then further characterized with respect to clinical and biomarker characteristics. We then classified FDG-PET scans of 217 amyloid-positive patients with mild cognitive impairment ("prodromal AD") according to the identified subtypes and studied their domain-specific cognitive trajectories and progression to dementia over a follow-up interval of up to 72 months.

RESULTS

Three main hypometabolic subtypes were identified: (i) "typical" (48.6%), showing a classic posterior temporo-parietal hypometabolic pattern; (ii) "limbic-predominant" (44.6%), characterized by old age and a memory-predominant cognitive profile; and (iii) a relatively rare "cortical-predominant" subtype (6.8%) characterized by younger age and more severe executive dysfunction. Subtypes classified in the prodromal AD sample demonstrated similar subtype characteristics as in the AD dementia sample and further showed differential courses of cognitive decline.

CONCLUSIONS

These findings complement recent research efforts on MRI-based identification of distinct AD atrophy subtypes and may provide a potentially more sensitive molecular imaging tool for early detection and characterization of AD-related neurodegeneration variants at prodromal disease stages.

Global longitudinal strain and mechanical dispersion at rest in exercise stress echocardiography for detecting obstructive coronary artery disease: a pilot study

Funding Acknowledgements

Type of funding sources: None.

BACKGROUND

Exercise stress echocardiography (ESE) is a commonly used investigation for risk stratification in coronary artery disease (CAD). The added value of resting indices such as Global Longitudinal Strain (GLS) and Mechanical Dispersion (MD) to detect obstructive CAD is not well established and would be of significant clinical benefit.

PURPOSE

To evaluate the diagnostic value of GLS and MD at rest and post-exercise during ESE to detect obstructive CAD, defined by angiographic stenosis >70% in any major coronary artery.

METHODS

Retrospective cohort study of 80 consecutive patients who underwent ESE and had coronary angiography (invasive or CT) within 6 months. Retrospective speckle tracking strain analysis was performed on digitally archived video-loops, using vendor independent software. Data on demographics, medications, outcomes and ESE characteristics were collected and analysed.

RESULTS

In 49 (61.3%) patients with any CAD >70%, GLS at rest was lower (-13.9% ± 4.2 vs -16.1% ± 5.2, p-value = 0.04), and MD at rest was higher (81ms ± 43 vs 58ms ± 28, p-value = 0.008), when compared to patients without CAD >70%. GLS and MD measured post-exercise were not significantly different between groups. Ejection fraction (EF) and Wall Motion Score Index (WMSI) at rest and post-exercise were not significantly different between groups. A resting GLS cutpoint of -14% had a sensitivity and specificity of 57/68%, comparable to the development of new regional wall motion abnormalities (71/39%) and peak WMSI >1.2 (59/48%). Additionally, in 39 (48.8%) patients who had >70% stenosis in the left anterior descending (LAD) artery, LS in the LAD territory segments was lower (-16.2% ± 4.4 vs -18.3% ± 4.7, p-value = 0.04), when compared to patients without >70% stenosis in the LAD artery.

CONCLUSION

Resting GLS was lower and MD higher in patients undergoing ESE, who have any CAD >70% compared to patients who do not have any CAD >70%. Resting GLS and MD may increase diagnostic accuracy during ESE to predict obstructive CAD. Further prospective studies evaluating the utility of resting indices to predict functionally significant CAD are required.

Portuguese adaptation of the S3-non-invasive ventilation (S3-NIV) questionnaire for home mechanically ventilated patients

Short, valid and easy to use tools are needed to monitor non-invasive ventilation in clinical practice and for organization of home mechanical ventilation services. The aim of this study was to develop a professional translation and cultural adaptation of the Portuguese S³ non-invasive ventilation questionnaire. 234 stable patients (128 male patients, 53.8%) with a mean age of 69.3 years under long-term home non-invasive ventilation were recruited from a single-center outpatient clinic. The most frequent diagnostic groups were obesity hypoventilation syndrome, chronic obstructive pulmonary disease and restrictive chest wall disorders. The Portuguese version of the questionnaire was obtained using translation back-translation process with two professional translators. Internal consistency for the total score was good (Cronbach's α coefficient of 0.76) as well as for the "respiratory symptoms" and the "sleep and side effects" domains (Cronbach's α coefficient=0.68 and Cronbach's α coefficient=0.72, respectively). An exploratory factor analysis was performed leading to an explained variance of 54.6%, and resulted in 3 components. The Portuguese version of the S3-NIV questionnaire is a simple and valid tool for the routine clinical assessment of patients receiving home NIV.

Structural imaging in dementia with Lewy bodies: the potential of multivariate data analysis

Structural imaging has a limited role in current diagnostic criteria for dementia with Lewy bodies (DLB), possibly since overt brain atrophy is uncommon in this disorder. Multivariate data analysis is promising in this context due to its superiority to detect subtle brain changes. This systematic review reports multivariate studies of structural imaging data in DLB. Preliminary evidence shows the capacity of structural imaging in discriminating DLB patients from Alzheimer's disease patients and healthy controls. Ongoing global initiatives will change statistical possibilities in DLB. Multivariate data analysis in DLB is an emerging field, and its use is encouraged.