Diagnostic and societal impact of implementing the syncope guidelines of the European Society of Cardiology (SYNERGY study).

BACKGROUND: Syncope management is fraught with unnecessary tests and frequent failure to establish a diagnosis. We evaluated the potential of implementing the 2018 European Society of Cardiology (ESC) Syncope Guidelines regarding diagnostic yield, accuracy and costs. METHODS: A multicentre pre-post study in five Dutch hospitals comparing two groups of syncope patients visiting the emergency department: one before intervention (usual care; from March 2017 to February 2019) and one afterwards (from October 2017 to September 2019). The intervention consisted of the simultaneous implementation of the ESC Syncope Guidelines with quick referral routes to a syncope unit when indicated. The primary objective was to compare diagnostic accuracy using logistic regression analysis accounting for the study site. Secondary outcome measures included diagnostic yield, syncope-related healthcare and societal costs. One-year follow-up data were used to define a gold standard reference diagnosis by applying ESC criteria or, if not possible, evaluation by an expert committee. We determined the accuracy by comparing the treating physician's diagnosis with the reference diagnosis. RESULTS: We included 521 patients (usual care, n = 275; syncope guidelines intervention, n = 246). The syncope guidelines intervention resulted in a higher diagnostic accuracy in the syncope guidelines group than in the usual care group (86% vs.69%; risk ratio 1.15; 95% CI 1.07 to 1.23) and a higher diagnostic yield (89% vs. 76%, 95% CI of the difference 6 to 19%). Syncope-related healthcare costs did not differ between the groups, yet the syncope guideline implementation resulted in lower total syncope-related societal costs compared to usual care (saving €908 per patient; 95% CI €34 to €1782). CONCLUSIONS: ESC Syncope Guidelines implementation in the emergency department with quick referral routes to a syncope unit improved diagnostic yield and accuracy and lowered societal costs. TRIAL REGISTRATION: Netherlands Trial Register, NTR6268.

AI-support for the detection of intracranial large vessel occlusions: One-year prospective evaluation.

Purpose: Few studies have evaluated real-world performance of radiological AI-tools in clinical practice. Over one-year, we prospectively evaluated the use of AI software to support the detection of intracranial large vessel occlusions (LVO) on CT angiography (CTA). Method: Quantitative measures (user log-in attempts, AI standalone performance) and qualitative data (user surveys) were reviewed by a key-user group at three timepoints. A total of 491 CTA studies of 460 patients were included for analysis. Results: The overall accuracy of the AI-tool for LVO detection and localization was 87.6%, sensitivity 69.1% and specificity 91.2%. Out of 81 LVOs, 31 of 34 (91%) M1 occlusions were detected correctly, 19 of 38 (50%) M2 occlusions, and 6 of 9 (67%) ICA occlusions. The product was considered user-friendly. The diagnostic confidence of the users for LVO detection remained the same over the year. The last measured net promotor score was -56%. The use of the AI-tool fluctuated over the year with a declining trend. Conclusions: Our pragmatic approach of evaluating the AI-tool used in clinical practice, helped us to monitor the usage, to estimate the perceived added value by the users of the AI-tool, and to make an informed decision about the continuation of the use of the AI-tool.

Systematic assessment of coronary calcium detectability and quantification on four generations of CT reconstruction techniques: a patient and phantom study.

In computed tomography, coronary artery calcium (CAC) scores are influenced by image reconstruction. The effect of a newly introduced deep learning-based reconstruction (DLR) on CAC scoring in relation to other algorithms is unknown. The aim of this study was to evaluate the effect of four generations of image reconstruction techniques (filtered back projection (FBP), hybrid iterative reconstruction (HIR), model-based iterative reconstruction (MBIR), and DLR) on CAC detectability, quantification, and risk classification. First, CAC detectability was assessed with a dedicated static phantom containing 100 small calcifications varying in size and density. Second, CAC quantification was assessed with a dynamic coronary phantom with velocities equivalent to heart rates of 60-75 bpm. Both phantoms were scanned and reconstructed with four techniques. Last, scans of fifty patients were included and the Agatston calcium score was calculated for all four reconstruction techniques. FBP was used as a reference. In the phantom studies, all reconstruction techniques resulted in less detected small calcifications, up to 22%. No clinically relevant quantification changes occurred with different reconstruction techniques (less than 10%). In the patient study, the cardiovascular risk classification resulted, for all reconstruction techniques, in excellent agreement with the reference (κ = 0.96-0.97). However, MBIR resulted in significantly higher Agatston scores (61 (5.5-435.0) vs. 81.5 (9.25-435.0); p < 0.001) and 6% reclassification rate. In conclusion, HIR and DLR reconstructed scans resulted in similar Agatston scores with excellent agreement and low-risk reclassification rate compared with routine reconstructed scans (FBP). However, caution should be taken with low Agatston scores, as based on phantom study, detectability of small calcifications varies with the used reconstruction algorithm, especially with MBIR and DLR.

The contemporary pulmonary artery catheter. Part 1: placement and waveform analysis.

Nowadays, the classical pulmonary artery catheter (PAC) has an almost 50-year-old history of its clinical use for hemodynamic monitoring. In recent years, the PAC evolved from a device that enabled intermittent cardiac output measurements in combination with static pressures to a monitoring tool that provides continuous data on cardiac output, oxygen supply and-demand balance, as well as right ventricular (RV) performance. In this review, which consists of two parts, we will introduce the difference between intermittent pulmonary artery thermodilution using cold bolus injections, and the contemporary PAC enabling continuous measurements by using a thermal filament which at random heats up the blood. In this first part, the insertion techniques, interpretation of waveforms of the PAC, the interaction of waveforms with the respiratory cycle and airway pressure as well as pitfalls in waveform analysis are discussed. The second part will cover the measurements of the contemporary PAC including measurement of continuous cardiac output, RV ejection fraction, end-diastolic volume index, and mixed venous oxygen saturation. Limitations of all of these measurements will be highlighted there as well. We conclude that thorough understanding of measurements obtained from the PAC are the first step in successful application of the PAC in daily clinical practice.

The contemporary pulmonary artery catheter. Part 2: measurements, limitations, and clinical applications.

Nowadays, the classical pulmonary artery catheter (PAC) has an almost 50-year-old history of its clinical use for hemodynamic monitoring. In recent years, the PAC evolved from a device that enabled intermittent cardiac output measurements in combination with static pressures to a monitoring tool that provides continuous data on cardiac output, oxygen supply and-demand balance, as well as right ventricular performance. In this review, which consists of two parts, we will introduce the difference between intermittent pulmonary artery thermodilution using bolus injections, and the contemporary PAC enabling continuous measurements by using a thermal filament which heats up the blood. In this second part, we will discuss in detail the measurements of the contemporary PAC, including continuous cardiac output measurement, right ventricular ejection fraction, end-diastolic volume index, and mixed venous oxygen saturation. Limitations of all of these measurements are highlighted as well. We conclude that thorough understanding of measurements obtained from the PAC is the first step in successful application of the PAC in daily clinical practice.

Factors facilitating and hindering the implementation of the European Society of Cardiology Syncope Guidelines at the Emergency Department: A nationwide qualitative study.

AIMS: Syncope care is often fragmented and inefficient. Structuring syncope care through implementation of guidelines and Syncope Units has been shown to improve diagnostic yield, reduce costs and improve quality of life. We implemented the European Society of Cardiology (ESC) 2018 syncope guidelines at the Emergency Departments (ED) and established Syncope Units in five Dutch hospitals. We evaluated the implementation process by identifying factors that hinder ('barriers') and facilitate ('facilitators') the implementation. METHODS AND RESULTS: We conducted, recorded and transcribed semi-structured interviews with 19 specialists and residents involved in syncope care from neurology, cardiology, internal medicine and emergency medicine. Two researchers independently classified the reported barriers and facilitators, according to the framework of qualitative research (Flottorp), which distinguished several separate fields ('levels'). Software package Atlas.ti was used for analysis. We identified 31 barriers and 22 facilitators. Most barriers occurred on the level of the individual health care professional (e.g. inexperienced residents having to work with the guideline at the ED) and the organizational context (e.g. specialists not relinquishing preceding procedures). Participants reported most facilitators at the level of innovation (e.g. structured work-flow at the ED). The multidisciplinary Syncope Unit was welcomed as useful solution to a perceived need in clinical practice. CONCLUSION: Implementing ESC syncope guidelines at the ED and establishing Syncope Units facilitated a structured multidisciplinary work-up for syncope patients. Most identified barriers related to the individual health care professional and the organizational context. Future implementation of the multidisciplinary guideline should be tailored to address these barriers.

Reduction of vascular leakage by imatinib is associated with preserved microcirculatory perfusion and reduced renal injury markers in a rat model of cardiopulmonary bypass.

BACKGROUND: Cardiopulmonary bypass during cardiac surgery leads to impaired microcirculatory perfusion. We hypothesized that vascular leakage is an important contributor to microcirculatory dysfunction. Imatinib, a tyrosine kinase inhibitor, has been shown to reduce vascular leakage in septic mice. We investigated whether prevention of vascular leakage using imatinib preserves microcirculatory perfusion and reduces organ injury markers in a rat model of cardiopulmonary bypass. METHODS: Male Wistar rats underwent cardiopulmonary bypass after treatment with imatinib or vehicle (n=8 per group). Cremaster muscle microcirculatory perfusion and quadriceps microvascular oxygen saturation were measured using intravital microscopy and reflectance spectroscopy. Evans Blue extravasation was determined in separate experiments. Organ injury markers were determined in plasma, intestine, kidney, and lungs. RESULTS: The onset of cardiopulmonary bypass decreased the number of perfused microvessels by 40% in the control group [9.4 (8.6-10.6) to 5.7 (4.8-6.2) per microscope field; P<0.001 vs baseline], whereas this reduction was not seen in the imatinib group. In the control group, the number of perfused capillaries remained low throughout the experiment, whilst perfusion remained normal after imatinib administration. Microvascular oxygen saturation was less impaired after imatinib treatment compared with controls. Imatinib reduced vascular leakage and decreased fluid resuscitation compared with control [3 (3-6) vs 12 ml (7-16); P=0.024]. Plasma neutrophil-gelatinase-associated-lipocalin concentrations were reduced by imatinib. CONCLUSIONS: Prevention of endothelial barrier dysfunction using imatinib preserved microcirculatory perfusion and oxygenation during and after cardiopulmonary bypass. Moreover, imatinib-induced protection of endothelial barrier integrity reduced fluid-resuscitation requirements and attenuated renal and pulmonary injury markers.

[Driving status of syncope patients is not part of standard advice]. / Rijgeschiktheid bij syncope niet standaard besproken.

OBJECTIVE: Some medical problems, such as syncope, have direct consequences for fitness to drive. Our objective was to discover if patients had been informed about their driving status after a syncopal episode by their physician, and if this advice was in line with current legislation. DESIGN: Cross-sectional study. METHOD: By means of a structured questionnaire, 150 patients referred to the syncope clinic at the Academic Medical Centre, Amsterdam, were asked about the advice they had received concerning their driving status during previous consultations with their general practitioner or specialists. A syncope expert then assessed the driving status of all patients in the light of the existing and new ruling. RESULTS: In 121 of the 150 patients (81%), a certain or highly-likely cause for their loss of consciousness was determined: 68 patients had reflex syncope, 25 patients orthostatic hypotension, 20 patients psychogenic pseudosyncope, three patients cardiac syncope, three patients had epilepsy and two patients another diagnosis. Seven patients had experienced an episode while driving. Only 26/150 patients (17%) reported that the consequences of their episodes for their driving status had been discussed with them at earlier consultations. If driving was discussed, in only 31% had the current Dutch legislation on driving been followed. Over a third (38%) of the patients felt they should no longer drive. CONCLUSION: Fewer than one in five patients reported that driving status was discussed by a physician after a syncope episode. If advice had been given, it was often not in line with current legislation.

[Carotid sinus massage is not a benign intervention]. / Carotismassage is geen onschuldige interventie.

Carotid sinus massage for diagnosis and termination of supraventricular tachycardia (SVT) is still a widely used vagal manoeuvre in the A&E department. However, itsefficacy is limited (termination of the SVT in approximately 20%) and carotid sinus massage may be complicated by (potentially devastating) neurologic complications in 0.2-1% of the patients. There are safer interventions without neurologic complications, such as the modified Valsalva manoeuvre (efficacy 43%) and intravenous administration of adenosine (efficacy 75%). Monitor observation of the heart rhythm is required, both for vagal manoeuvres and for adenosine administration, because of the possibility of ventricular tachycardia or ventricular fibrillation induction (incidence 0.08%). Carotid sinus massage remains an important diagnostic method in patients with unexplained syncope in whom, based on the clinical history, carotid sinus hypersensitivity is suspected. It should be avoided in patients with previous TIA or stroke within the past 3 months, or those with carotid bruits, except if carotid Doppler studies have excluded significant stenosis (≥ 70%).

Long-term outcomes and cost effectiveness of high-dose dexamethasone for cardiac surgery: a randomised trial.

Prophylactic intra-operative administration of dexamethasone may improve short-term clinical outcomes in cardiac surgical patients. The purpose of this study was to evaluate long-term clinical outcomes and cost effectiveness of dexamethasone versus placebo. Patients included in the multicentre, randomised, double-blind, placebo-controlled DExamethasone for Cardiac Surgery (DECS) trial were followed up for 12 months after their cardiac surgical procedure. In the DECS trial, patients received a single intra-operative dose of dexamethasone 1 mg.kg-1 (n = 2239) or placebo (n = 2255). The effects on the incidence of major postoperative events were evaluated. Also, overall costs for the 12-month postoperative period, and cost effectiveness, were compared between groups. Of 4494 randomised patients, 4457 patients (99%) were followed up until 12 months after surgery. There was no difference in the incidence of major postoperative events, the relative risk (95%CI) being 0.86 (0.72-1.03); p = 0.1. Treatment with dexamethasone reduced costs per patient by £921 [€1084] (95%CI £-1672 to -137; p = 0.02), mainly through reduction of postoperative respiratory failure and duration of postoperative hospital stay. The probability of dexamethasone being cost effective compared with placebo was 97% at a threshold value of £17,000 [€20,000] per quality-adjusted life year. We conclude that intra-operative high-dose dexamethasone did not have an effect on major adverse events at 12 months after cardiac surgery, but was associated with a reduction in costs. Routine dexamethasone administration is expected to be cost effective at commonly accepted threshold levels for cost effectiveness.

LEAD COMPOSITE VS. NONLEAD PROTECTIVE GARMENTS: WHICH ARE BETTER? A MULTIVENDOR COMPARISON.

This study aims to provide more insight in attenuation characteristics and corresponding lead (Pb) equivalences of a broad range of commercially available lead composite and nonlead protective garments. Thirty garments of five manufacturers (listed as 0.25-0.35-0.50 mm Pb equivalent) were tested. Transmission values were determined at 70, 90 and 110 kVp using an inverse broad beam geometry. Pb equivalence was determined using lead sheets as reference material. A substantial variability in photon transmission across garments was found. Differences between lead composite and nonlead garments were not statistically significant. Depending on tube voltage, between 9 and 12 out of 30 garments had a lower Pb equivalence than the indicated value. This work shows that lead equivalence as indicated on a garment's label may overestimate its protective performance. Depending on the application a more thorough verification of the effectiveness of protective garments at the desired kVp is warranted.

Electrocardiographic abnormalities in patients admitted for hip fracture.

BACKGROUND: Several risk factors for falls and hip fractures have been recognised, but controversy still exists regarding the importance of rhythm and conduction abnormalities as potentially modifiable risk factors for recurrent falls. The aim of this study was to determine the prevalence of clinically relevant ECG abnormalities in patients with a hip fracture versus controls. METHODS: The study was designed as a case-control study within consecutive hip surgery patients in an academic hospital. CASES: patients with traumatic hip fractures. CONTROLS: patients undergoing planned hip surgery (non-traumatic). CASES and controls were 1:1 matched for age and gender. INCLUSION CRITERIA: age ≥ 50 years. EXCLUSION CRITERIA: high-energy trauma, pathological and÷or previous hip fracture. ECGs were scored using predefined categories. Multivariate logistic regression was performed to calculate odds ratios (OR) and to correct for confounders. RESULTS: We included 888 patients (444 cases). Mean age was 70.9 years (SD 9.3), 70% were female. After correction for potential confounders we found the following associations between clinically relevant ECG abnormalities and hip fractures: atrial fibrillation OR 2.7 (95% CI 1.2-6.1), abnormal QTc prolongation OR 3.9 (2.2-6.8), sinus tachycardia OR 5.0 (2.1-11.8) and sinus bradycardia OR 0.3 (0.1-0.5). Univariately, several markers for decreased cardiac function were also associated with hip fractures. CONCLUSIONS: Hip fracture patients are at higher risk for ECG abnormalities than matched patients undergoing hip surgery for other indications. To potentially reduce the risk of future (injurious) falls, increased awareness of these ECG abnormalities is warranted to assess the need for further cardiovascular fall risk assessment.

Cone beam CT guidance provides superior accuracy for complex needle paths compared with CT guidance.

OBJECTIVE: To determine the accuracy of cone beam CT (CBCT) guidance and CT guidance in reaching small targets in relation to needle path complexity in a phantom. METHODS: CBCT guidance combines three-dimensional CBCT imaging with fluoroscopy overlay and needle planning software to provide real-time needle guidance. The accuracy of needle positioning, quantified as deviation from a target, was assessed for inplane, angulated and double angulated needle paths. Four interventional radiologists reached four targets along the three paths using CBCT and CT guidance. Accuracies were compared between CBCT and CT for each needle path and between the three approaches within both modalities. The effect of user experience in CBCT guidance was also assessed. RESULTS: Accuracies for CBCT were significantly better than CT for the double angulated needle path (2.2 vs 6.7 mm, p<0.001) for all radiologists. CBCT guidance showed no significant differences between the three approaches. For CT, deviations increased with increasing needle path complexity from 3.3 mm for the inplane placements to 4.4 mm (p=0.007) and 6.7 mm (p<0.001) for the angulated and double angulated CT-guided needle placements, respectively. For double angulated needle paths, experienced CBCT users showed consistently higher accuracies than trained users [1.8 mm (range 1.2-2.2) vs 3.3 mm (range 2.1-7.2) deviation from target, respectively; p=0.003]. CONCLUSION: In terms of accuracy, CBCT is the preferred modality, irrespective of the level of user experience, for more difficult guidance procedures requiring double angulated needle paths as in oncological interventions. ADVANCES IN KNOWLEDGE: Accuracy of CBCT guidance has not been discussed before. CBCT guidance allows accurate needle placement irrespective of needle path complexity. For angulated and double-angulated needle paths, CBCT is more accurate than CT guidance.

At the heart of the arterial baroreflex: a physiological basis for a new classification of carotid sinus hypersensitivity.

The aim of this review is to provide an update of the current knowledge of the physiological mechanisms underlying reflex syncope. Carotid sinus syncope will be used as the classical example of an autonomic reflex with relatively well-established afferent, central and efferent pathways. These pathways, as well as the pathophysiology of carotid sinus hypersensitivity (CSH) and the haemodynamic effects of cardiac standstill and vasodilatation will be discussed. We will demonstrate that continuous recordings of arterial pressure provide a better understanding of the cardiovascular mechanisms mediating arterial hypotension and cerebral hypoperfusion in patients with reflex syncope. Finally we will demonstrate that the current criteria to diagnose CSH are too lenient and that the conventional classification of carotid sinus syncope as cardioinhibitory, mixed and vasodepressor subtypes should be revised because isolated cardioinhibitory CSH (asystole without a fall in arterial pressure) does not occur. Instead, we suggest that all patients with CSH should be thought of as being 'mixed', between cardioinhibition and vasodepression. The proposed stricter set of criteria for CSH should be evaluated in future studies.

Mistakes that affect others: an fMRI study on processing of own errors in a social context.

In social contexts, errors have a special significance and often bear consequences for others. Thinking about others and drawing social inferences in interpersonal games engages the mentalizing system. We used neuroimaging to investigate the differences in brain activations between errors that affect only agents themselves and errors that additionally influence the payoffs of interaction partners. Activation in posterior medial frontal cortex (pMFC) and bilateral insula was increased for all errors, whereas errors that implied consequences for others specifically activated medial prefrontal cortex (mPFC), an important part of the mentalizing system. The results demonstrate that performance monitoring in social contexts involves additional processes and brain structures compared with individual performance monitoring where errors only have consequences for the person committing them. Taking into account how one's behavior may affect others is particularly crucial for adapting behavior in interpersonal interactions and joint action.

Spatial and effector processing in the human parietofrontal network for reaches and saccades.

It is generally accepted that interactions between parietal and frontal cortices subserve the visuomotor processing for eye and hand movements. Here, we used a sequential-instruction paradigm in 3-T functional MRI to test the processing of effector and spatial signals, as well as their interaction, as a movement is composed and executed in different stages. Subjects prepared either a saccade or a reach following two successive visual instruction cues, presented in either order. One cue instructed which effector to use (eyes, right hand); the other signaled the spatial goal (leftward vs. rightward target location) of the movement. During the first phase of the prepared movement, after cueing of either goal or effector information, we found significant spatial goal selectivity but no effector specificity along the parietofrontal network. During the second phase of the prepared movement, when both goal and effector information were available, we found a large overlap in the neural circuitry involved in the planning of eye and hand movements. Gradually distributed along this network, we observed clear spatial goal selectivity and limited, but significant, effector specificity. Regions in the intraparietal sulcus and the dorsal premotor cortex were selective to both goal location and motor effector. Taken together, our results suggest that the relative weight of spatial goal and effector selectivity changes along the parietofrontal network, depending on the status of the movement plan.

Cerebral correlates of motor imagery of normal and precision gait.

We have examined the cerebral structures involved in motor imagery of normal and precision gait (i.e., gait requiring precise foot placement and increased postural control). We recorded cerebral activity with functional magnetic resonance imaging while subjects imagined walking along paths of two different widths (broad, narrow) that required either normal gait, or exact foot placement and increased postural control. We used a matched visual imagery (VI) task to assess the motor specificity of the effects, and monitored task performance by recording imagery times, eye movements, and electromyography during scanning. In addition, we assessed the effector specificity of MI of gait by comparing our results with those of a previous study on MI of hand movements. We found that imagery times were longer for the narrow path during MI, but not during VI, suggesting that MI was sensitive to the constraints imposed by a narrow walking path. Moreover, MI of precision gait resulted in increased cerebral activity and effective connectivity within a network involving the superior parietal lobules, the dorsal precentral gyri, and the right middle occipital gyrus. Finally, the cerebral responses to MI of gait were contiguous to but spatially distinct from regions involved in MI of hand movements. These results emphasize the role of cortical structures outside primary motor regions in imagining locomotion movements when accurate foot positioning and increased postural control is required.

64 slice MDCT generally underestimates coronary calcium scores as compared to EBT: a phantom study.

The objective of our study was the determination of the influence of the sequential and spiral acquisition modes on the concordance and deviation of the calcium score on 64-slice multi-detector computed tomography (MDCT) scanners in comparison to electron beam tomography (EBT) as the gold standard. Our methods and materials were an anthropomorphic cardio CT phantom with different calcium inserts scanned in sequential and spiral acquisition modes on three identical 64-slice MDCT scanners of manufacturer A and on three identical 64-slice MDCT scanners of manufacturer B and on an EBT system. Every scan was repeated 30 times with and 15 times without a small random variation in the phantom position for both sequential and spiral modes. Significant differences were observed between EBT and 64-slice MDCT data for all inserts, both acquisition modes, and both manufacturers of MDCT systems. High regression coefficients (0.90-0.98) were found between the EBT and 64-slice MDCT data for both scoring methods and both systems with high correlation coefficients (R2>0.94). System A showed more significant differences between spiral and sequential mode than system B. Almost no differences were observed in scanners of the same manufacturer for the Agatston score and no differences for the Volume score. The deviations of the Agatston and Volume scores showed regression dependencies approximately equal to the square root of the absolute score. The Agatston and Volume scores obtained with 64-slice MDCT imaging are highly correlated with EBT-obtained scores but are significantly underestimated (-10% to -2%) for both sequential and spiral acquisition modes. System B is more independent of acquisition mode to calcium score than system A. The Volume score shows no intramanufacturer dependency and its use is advocated versus the Agatston score. Using the same cut points for MDCT-based calcium scores as for EBT-based calcium scores can result in classifying individuals into a too low risk category. System information and scanprotocol is therefore needed for every calcium score procedure to ensure a correct clinical interpretation of the obtained calcium score results.