bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid recognition of out-of-hospital cardiac arrest by emergency medical dispatchers is associated with improved survival
Authors: Gnesin F , Moeller A.L , Mills E.H.A , Zylyftari N , Jensen B , Boeggild H , Ringgren K.B , Kragholm K , Lippert F , Folke F , Gislason G , Torp-Pedersen C.T 
Published: November 2020

Abstract

Background
Emergency medical dispatchers' (EMD) recognition of out-of-hospital cardiac arrest (OHCA) is an essential part of the first link in the Chain of Survival. However, it is unknown whether the time-to-recognition of OHCA by EMD during an emergency call is associated with survival.

Purpose
To investigate the effect of time-to-recognition on 30-day survival among patients with recognised OHCA.

Methods
We linked data on OHCAs occurring in the Capital Region of Denmark from 2016 through 2017 to records of corresponding emergency calls. We defined recognition as dispatching an ambulance with an appropriate priority level and subsequently defined time-to-recognition as the time from start of the call to the time of dispatching the ambulance. Among patients with recognised OHCA, we performed uni- and multivariate logistic regression to investigate the association of time-to-recognition and 30-day survival and reported odds ratios (OR) with 95% confidence intervals (CI).

Results
Among 2,382 patients with OHCA, 94.2% were recognised, in which median age was 73.6 years, 61.6% were males and median time-to-recognition was 0.8 minutes (interquartile range 0.7 minutes). Patients for whom time-to-recognition was up to (but not including) one minute had more than three-fold higher probability of surviving 30 days (15.5%) compared to patients for whom time-to-recognition was three or more minutes (4.5%) (Figure 1). Time-to-recognition was significantly associated with 30-day survival: OR 0.75 per minute (95% CI 0.62–0.91, P&lt;0.005), and results were similar in the adjusted analysis: OR 0.72 per minute (95% CI 0.58–0.90, P&lt;0.005).

Conclusion
Rapid recognition of OHCA by EMD resulted in improved survival rate of patients. This was particularly evident when time-to-recognition was three or more minutes.
Figure 1

Funding Acknowledgement
Type of funding source: Foundation. Main funding source(s): Hjerteforeningen
Countdown to physician-free EKG interpretation
Authors: Mehta S , Avila J , Niklitschek S , Fernandez F , Villagran C , Vera F , Rocuant R , Cardenas G , Frauenfelder A , Vieira D , Quintero S , Vijayan Y , Merchant S , Narvaez-Caicedo C , Sanchez C 
Published: November 2020

Abstract

Background
With the introduction of electronic medical records and other digital platforms, the classification and coding of different medical entities have become a complex, cumbersome task that is prone to diagnostic inconsistencies and errors. By incorporating Artificial Intelligence (AI) to a massive database of EKG records, we have developed an innovative methodology to accurately discriminate an EKG as “normal” or “abnormal”. We firmly believe that this algorithm sets up medicine on a path of complete computer-aided EKG interpretation.

Purpose
To present a viable AI-guided filter that can accurately discriminate between normal and abnormal EKG within a cardiologist-annotated EKG database.

Methods
An observational, retrospective, case-control study. Samples: A total of 140,000 randomly sampled 12-lead ECG of 10-seconds length with a sampling frequency of 500 [Hz] from Brazil (BR) and Colombia (CO) (divided as 70,000 normal and 70,000 abnormal EKG records per country dataset) were derived from the private International Telemedical System (ITMS) database from September 2018 to July 2019. Only de-identified records were used, records with artifacts were excluded. Preprocessing: Only the first 2s of each short lead and 9s of the long lead were considered. This data includes mobile (MOB) and transtelephonic (TTP) EKGs (50/50 ratio). Limb leads I, II and III and precordial leads V1, V2, V3 and V5 were used. The mean was removed from each lead. Training Sets: Four models were trained as depicted in the figure below. Each training dataset has 25,000 Normal and 25,000 Abnormal records, where 10% of the total records were used as a validation set. The test sets included 10,000 normal, and 10,000 abnormal records each. Testing and Class Assigning: An inception convolutional neural network was implemented; Each model was tested with 5,000 normal and 5,000 abnormal records of the corresponding country and transmission type with which they were trained. “Normal” or “Abnormal” labels were assigned to each EKG record and were compared to the cardiologists' reports; performance indicators (accuracy, sensitivity, and specificity) were calculated for each model.

Results
An overall accuracy of 82.4%; sensitivity of 88.7%; and specificity of 76.2% was achieved amongst the 4 testing models (Separate results of each training set are shown below).

Conclusion(s)
AI enables the interpretation of digital EKG records to be exercised in an organized, accurate, and straightforward manner, taking into consideration the multiple potential entities that can be diagnosed through this historical triage tool. By quickly identifying the normal records, the cardiologist is able to invest efforts in treating patients in a timely manner.

Funding Acknowledgement
Type of funding source: None
Presentation characteristics, use of treatments and outcomes in patients with ischaemic vs. non-ischaemic cardiogenic shock
Authors: Schrage B , Dabboura S , Yan I , Hilal R , Weimann J , Becher P.M , Seiffert M , Blankenberg S , Westermann D 
Published: November 2020

Abstract

Aim
Evidence on non-ischaemic cardiogenic shock (CS) is scarce. The aim of this study was to investigate differences in presentation characteristics, use of treatments and outcomes in patients with ischaemic vs. non-ischaemic CS.

Methods
Patients with CS admitted to a tertiary care hospital between October 2009 and October 2017 were identified and stratified as ischaemic CS/non-ischaemic CS based on the presence/absence of acute myocardial infarction. Missing data was handled by chained equation multiple imputation. Logistic and Cox regression models were fitted to investigate the association of non-ischaemic CS with presentation characteristics (adjusted for all baseline variables), and use of treatments as well as30-day in-hospital mortality (adjusted for relevant confounders including age, sex, prior cardiac arrest, haemodynamics, pH and lactate).

Results
A total of 978 patients were enrolled in this study; median age was 70 (interquartile range 58, 79) years and 70% were male. 505 patients (43%) had non-ischaemic CS. Patients with non-ischaemic CS were more likely younger and female; were less likely to be active smokers or to have diabetes, but more likely to have chronic renal disease and history of myocardial infarction; and were more likely to present with unfavourable haemodynamics and with mechanical ventilation. Regarding use of treatments, patients with non-ischaemic CS were more likely to be treated with catecholamines [odds ratio (OR) 1.58, 95% confidence interval (CI) 1.11–2.27, p0.01], but less likely to be treated with extracorporeal membrane oxygenation (OR 0.66, 95% CI 0.48–0.92, p=0.02) or percutaneous left ventricular assist devices (OR 0.51, 0.35–0.74, p&lt;0.01). Unadjusted survival probabilities in patients with non-ischaemic vs. ischaemic CS were 36% (95% CI 32–42%) vs. 39% (95% CI 35–45%). After adjustment for multiple relevant confounders, non-ischaemic CS was associated with a significant increase in the risk of 30-day in-hospital mortality (hazard ratio 1.30, 95% CI 1.09–1.55, p&lt;0.01, Figure 1).

Conclusion
In this large study, non-ischaemic CS accounted for almost 50% of all CS cases. Non-ischaemic CS was not only associated with relevant differences in presentation characteristics and use of treatments, but also with a worse prognosis. These findings highlight the need for effective treatment strategies for patients with non-ischaemic CS.
Figure 1

Funding Acknowledgement
Type of funding source: None
Early Impella support in post-cardiac arrest cardiogenic shock complicating acute myocardial infarction improves short and long term survival
Authors: Hatzis G , Markus B , Luesebrink U , Ahrens H , Divchev D , Syntila S , Schieffer B , Karatolios K 
Published: November 2020

Abstract

Background
Early mechanical circulatory support with Impella may improve survival outcomes in the setting of post-cardiac arrest cardiogenic shock (CS) after out of hospital cardiac arrest (OHCA) complicating acute myocardial infarction (AMI). However, the optimal timing to initiate mechanical circulatory support (MCS) in this particular setting remains unclear.

Purpose
We aimed to compare survival outcomes of patients supported with Impella 2.5 before percutaneous coronary intervention (PCI) (pre-PCI) to those supported after PCI (post-PCI).

Methods
Single center study of patients resuscitated from OHCA due to AMI with post-cardiac arrest CS between September 2014 and June 2018. Survival outcomes were compared between those with Impella support before and after PCI.

Results
A total of 65 consecutive patients with infarct-related post-cardiac arrest shock supported with Impella 2.5 during admission coronary angiogram were included. All patients were in profound CS requiring catecholamines on admission. Overall survival to discharge and at 12-months was 44.6% and 41.5%, respectively. Patients in the pre-PCI group had a higher survival to discharge and at 12-months as compared to patients of the post-PCI group (60.7% versus 32.4%, p=0.03 and 57.1% versus 29.7%, p=0.04, respectively). Moreover, the patients in the early support group demonstrated a greater functional recovery of the left ventricle when Impella support was initiated prior to PCI.

Conclusions
Our results suggest that the early initiation of MCS with Impella 2.5 prior to PCI is associated with improved hospital and 12-month survival in patients with post-cardiac arrest CS complicating AMI.
Figure 1

Funding Acknowledgement
Type of funding source: None
Ejection dynamics and valve kinetics in patients with low-gradient severe aortic stenosis with preserved ejection fraction. Comparison between normal and low-flow
Authors: Migliore R , Adaniya M.E , Barranco M.A , Gonzalez S , Miramont G 
Published: November 2020

Abstract

Background
Studies of ejection dynamics in severe aortic stenosis and prosthetic valve obstruction had demonstrated a delay in aortic valve opening.

Purpose
The aim of this study was to compare and evaluate ejection dynamics and valve kinetics in patients with severe aortic stenosis with preserved ejection fraction with normal and low flow.

Methods
83 patients (age average 68±11 years) with severe aortic stenosis (aortic valve area &lt;1cm2) and preserved ejection fraction (≥50%) were studied with Doppler echocardiography and included prospectively. The ratio of aortic valve area measured at mid-deceleration and mid-acceleration (Md/Ma) were calculated using velocity of left ventricular outflow tract and aortic transvalvular velocity in continuity equation as an index of valvular kinetics. A ratio of Md/Ma &gt;1 indicate delay in opening of aortic valve. Assessment of ejection dynamics was evaluated with acceleration time (AT), ejection time (ET) and the ratio AT/ET estimated from aortic Doppler velocities profiles. Aortic flow was calculated as stroke volume/ET. According to stroke volume index and mean gradient patients were classified in 3 groups: normal-flow, low-gradient (NFLG) 25 patients, low-flow, low-gradient (LFLG) 28 patients and normal-flow, high-gradient (HG) 30 patients. Analysis of the variance and coefficient of correlation “r” were used for statistical evaluation. A p value &lt;0.05 was considered significant.

Results
There was no significant difference among the 3 groups with regard to ratio Md/Ma: NFLG 1.29±0.38, LFLG 1.22±0.26 and HG 1.23±0.45, NS. No difference was found in AT in the 3 groups, but ET was shorter in LFLG (310±30 ms) in comparison with NFLG (345±32 ms) and HG (361±31 ms), p&lt;0.01. Ratio AT/ET occurred in early systole in NFLG (0.27±0.07) compared with LFLG (0.32±0.07) and HG (0.39±0.07), p&lt;0.01. As expected, flow was decreased in LFLG (163±20 ml/s, p&lt;0.001) compared with NFLG (217±13 ml/s) and HG (233±44 ml/s). There was no correlation among AT/ET and aortic flow or stroke volume index.

Conclusions
There were not differences among the groups with regard to kinetic of the valve evaluated by mean of ratio Md/Ma. According to ratio AT/ET, aortic valve takes less time to open in NFLG compared with LFLG and HG independent of aortic flow suggesting a different ejection dynamics pattern in this group.

Funding Acknowledgement
Type of funding source: None
Heritability of aortic valve stenosis and evidence of bicuspid enrichment in families with tricuspid aortic valve stenosis
Authors: Boureau A , Le Souarnec S , Dina C , Karakachoff M , Capoulade R , Piriou N , Cueff C , Probst V , Schott J.J , Le Tourneau T 
Published: November 2020

Abstract

Background
Calcific aortic valve stenosis (CAVS) is the most common valvular heart disease. Although a familial component has been described, the heritability remains unknown. This study aimed to determine the heritability of CAVS and to compare the prevalence of bicuspid aortic valve (BAV) relatives among families with tricuspid and bicuspid aortic valve phenotype and to a control cohort.

Methods
Probands were recruited following aortic valve replacement in three French university hospitals. All relatives who agreed to participate were enrolled in the study. Families were defined as tricuspid aortic valve (TAV) or BAV families based on the aortic valve phenotype observed in the proband. As control group, we used probands diagnosed with mitral valve prolapse and their families. All recruited probands and relatives underwent comprehensive transthoracic echocardiography to determine aortic valve morphology and CAVS status. Additive genetic heritability was performed with SOLAR genetic statistics package. Prevalence of BAV relatives in each sub-group and Prevalence Ratio were calculated.

Results
Within the 2371 relatives coming from 138 CAVS families, the heritability of CAVS was significant (h2=0.49, p&lt;0.001). Furthermore, TAV stenosis heritability was only significant in TAV families (h2=0.20, p=0.013). The prevalence of BAV was significantly higher in TAV families and BAV families than control families (5.96 [95% CI: 4.2–8.3%], [n=32 of 537] vs. 2.49 [95% CI: 1.3–4.7%], [n=9 of 361]; PR 2.64 [95% CI: 1.41–5.91]; p=0.005 and 10.20 [95% CI: 7.0–14.5%], [n=26 of 255] vs. 2.49 [95% CI: 1.3–4.7%], [n=9 of 361]; PR 4.63 [95% CI: 2.35–13.44]; p&lt;0.001; respectively).

Conclusions
The heritability of aortic valve stenosis in this population confirms the genetic effect in determining aortic stenosis for all aortic valve phenotype and for tricuspid aortic valve. The bicuspid enrichment in TAV families suggests common genetic predisposition of aortic valve stenosis in some families. Taking all together, these findings encourage echocardiography screening of relatives of affected individuals.

Funding Acknowledgement
Type of funding source: None
ECG modifications, life-threatening ventricular arrhythmias and relation to mitral valve apparatus phenotype in mitral valve prolapse
Authors: Stevant D , Plessis M , Gourraud J.B , Cueff C , Piriou N , Thollet A , Probst V , Le Tourneau T 
Published: November 2020

Abstract

Background
Mitral valve prolapse (MVP) is a common condition in the general population, which can be associated to non-specific ECG abnormalities described initially as ST segment depression, T waves flattening or inversion, especially in the inferior leads. Lately, this type of ECG abnormalities has been reported in patients with MVP and ventricular arrhythmias (VA) or sudden death (SD). However, the prevalence of ECG abnormalities has never been studied in a large series of patients, and the link between ECG abnormalities, VA and SD to echocardiography examination has never been prospectively assessed.

Objective
To study the prevalence of ECG abnormalities including ventricular arrhythmias in MVP patients and their link with echocardiographic characteristics.

Methods
All patients (n=731, MVP = 486, Controls = 245) were prospectively enrolled and underwent a comprehensive echocardiography and ECG. In MVP patients 81 had minimal systolic displacement (MSD), 92 isolated MVP, 108 mild-moderate MR, and 196 severe MR. A comprehensive qualitative and quantitative analysis of ECG obtained from rest ECG, 24-hours ECG recording or exercise stress tests, was carried out. Mean follow-up was 4.4 years.

Results
The mains ECG abnormalities were an inversion of T wave in the inferior leads found in 12 MVP vs 1 control (2.5 vs 0.4%, P=0.047) or a QRS notch (5.1 vs 2.9%, P=0.13). In bileaflet MVP T wave inversion was more frequent as compared with other MVP patients (3.8 vs 0.8%, P=0.039). In addition there was a progressive prolongation of PR interval, QRS duration and increase QT dispersion associated with worsening of MR and heart chambers remodeling. None of ECG findings were significantly linked with the presence of MVP only. Out of 731 individuals, 27 (3.7%) had an history of VA or SD. In a multivariate analysis, bileaflet prolapse and mitral annulus disjunction were associated with VA or SD, whereas none of ECG criterion was associated with.

Conclusion
In this large prospective series of MVP patients, prevalence of inferior leads ECG abnormalities is very low. Prolongation of atrio-ventricular and ventricular conduction, as well increased QT dispersion is associated with worsening of MR and LV remodeling. Bileaflet prolapse and mitral annulus disjunction are associated with VA or SD.

Funding Acknowledgement
Type of funding source: None
The truly forgotten chamber: prognostic value of right atrial dilation in patients with sinus rhythm and significant functional tricuspid regurgitation
Authors: Fortuni F , Dietz M.F , Prihadi E.A , Priori S.G , Bax J.J , Delgado V , Ajmone Marsan N 
Published: November 2020

Abstract

Background
Functional tricuspid regurgitation (FTR) can be caused by right ventricular (RV) and/or right atrial (RA) dilation, and it leads in turn to further RV and RA remodeling. While it is known that in these patients RV dilation is associated with worse prognosis, there are no data on the prognostic value of RA enlargement.

Purpose
To assess the prognostic impact of RA dilation in patients with significant (≥ moderate) FTR taking into account the presence of atrial fibrillation (AF).

Methods
1382 patients (mean age: 69±13 year; 50% male) with moderate or severe FTR were included. Patients with congenital heart disease were excluded. Significant RA enlargement was identified by the value of RA area associated with excess of mortality according to spline curve analysis in the overall population (30 cm2 – Figure: Left Panel). The prognostic value of RA enlargement was investigated separately in patients with sinus rhythm (SR) and AF. The primary endpoint was all-cause mortality.

Results
A total of 987 (71%) patients were in SR while the remaining 395 (29%) had AF at the time of significant FTR diagnosis. Patients in SR with RA enlargement were more likely to present with RV failure symptoms and to receive diuretics compared with patients in SR with non-enlarged RA, whereas these differences were not detected in patients with AF. During a median follow-up of 53 (interquartile range, 20–89) months, 698 (51%) patients died. The survival rates of patients in SR with RA enlargement were significantly worse compared to the ones of patients in SR with normal RA size (Figure: Right Panel). In contrast, RA enlargement did not affect the prognosis of patients in AF (Log-rank χ2: 0.41; P=0.522). RA enlargement was associated with 33% increase risk of all-cause mortality in patients with SR and this association was retained on a multivariable Cox regression analysis (HR 1.27; 95% CI 1.04–1.56; P=0.022) together with older age, coronary artery disease, diabetes, severe renal impairment, reduced left ventricular or RV systolic function, and increased pulmonary artery pressures.

Conclusion
RA enlargement has an independent prognostic value for all-cause mortality in patients with FTR and SR, and therefore its evaluation might be useful to further improve their risk stratification.

Funding Acknowledgement
Type of funding source: None
Left atrial emptying fraction: a powerful predictor of events in severe aortic stenosis
Authors: Goncalves V , Ferreira J , Almeida J , Freitas A , Martins R , Vieira H , Goncalves L 
Published: November 2020

Abstract

Background
Increasing evidence suggests that left atrial (LA) structural and functional changes have an important role in risk stratification and prediction of clinical outcomes. We know from multiple data that left atrial maximum volume (LAVI), measured at end-systole, is a powerful prognostic marker in multiple patient groups. However, recent studies have suggested that this marker may not be the best representative of diastolic function as it does not image the full spectrum of atrial mechanics. Another measure of LA function is the left atrial emptying fraction (LAEF), which has proved to be a significant prognostic marker in many patient groups. Less known is its role in event prediction in severe aortic stenosis patients, a disease with a very important burden in modern societies.

Purpose
The authors hypothesised that LAEF is a powerful predictor of clinical outcomes at 1 year in patients with severe aortic stenosis.

Methods
We retrospectively evaluated 151 patients referred to our echocardiography laboratory with the diagnosis of severe aortic stenosis. All patients underwent transthoracic echocardiography. LA maximum volume was indexed to body surface area. LAEF was calculated as LAVI-LA minimum volume divided by LAVI. Patients were followed for 1 year regarding clinical outcomes. Clinical outcome was defined as a composite of hospital admission for a cardiovascular (CV) cause, emergency department recurrence for a CV cause or CV death. Logistic binary regression was used to evaluate associations of LAEF with the outcome.

Results
A total of 51.7% of patients (n=78) were males. Mean patient age was 76.6±8.0 years. A total of 38.4% of patients were diabetics (n=56), 96% had dyslipidaemia (n=145) and 25% (n=37) had atrial fibrillation. Mean left ventricular ejection fraction (LVEF) was 60.6±7.3, and mean LAVI was 41.4±12.1. In a multivariable regression model including clinical and echocardiographic markers, higher LAVI and pulmonary artery systolic pressure (PASP) were associated with lower LAEF. Receiver operating characteristic curve analysis showed that the predictive value of LAEF for outcomes at 1 year was 0.693 (AUC=0.693, CI 95% 0.578–0.809, p=0.002), performing better than other echocardiographic markers such as LAVI (AUC=0.567, CI 95% 0.440–0.694, p=0.286), PASP (AUC=0.582, CI 95% 0.451–0.714, p=0.191) and LVEF (AUC=0.590, CI 95% 0.464–0.716, p=0.153). After adjustment of baseline characteristics, a LAEF less than 41.3% remained a good predictor of clinical outcomes at 1 year (OR 2.615, CI 95% 1.085–6.305, p=0.32).

Conclusions
In this cohort of severe aortic stenosis patients, a reduced LAEF was associated with greater incidence of cardiovascular events, being a stronger predictor than LAVI, PASP or LVEF. This study suggests that LA dysfunction over LA volumes correlates better with clinical outcomes.

Funding Acknowledgement
Type of funding source: None