Characteristics and factors associated to patients discharging from hospital without an implantable cardioverter defibrillator after out-of-hospital cardiac arrest

AIMS

Guidelines recommend that in the absence of reversible cause for sudden cardiac arrest (SCA), implantable cardioverter defibrillator (ICD) should be performed to prevent further fatal event. We sought to describe the frequency and characteristics of patients discharged from the hospital without ICD after the SCA in the daily practice.

METHODS AND RESULTS

From 2011 to 2018, all SCAs related to a cardiac cause admitted alive across the 48 hospitals of Great Paris Area were prospectively enrolled. Two investigators thoroughly reviewed each medical report to ensure accuracy of the assigned diagnosis towards identifying the cause of SCA and ICD implantation. Out of the 4314 SCA admitted alive at hospital admission, 1064 cardiac-related SCA survivors were discharged alive from hospital, including 356 patients (33.5%) with an ICD and 708 (66.5%) without. The principal underlying cause of SCA among those discharged without an ICD was acute coronary syndrome (ACS; 602, 85%), chronic coronary artery disease (41, 5.8%), structural non-ischaemic heart disease (48, 6.8%), and non-structural heart disease (17, 2.4%). Among ACS-related SCA, 93.8% (602/642) discharged without an ICD. The unique factor associated with non-ICD implantation in the setting of ACS was immediate coronary angioplasty (odds ratio 4.22, 95% confidence interval 1.86-9.30, P < 0.001).

CONCLUSION

Two-thirds of SCA survivors were discharged without an ICD, mainly in the setting of ACS. The unique factor associated with non-ICD implantation among ACS was immediate coronary angioplasty emphasizing the fact that ACS definition must be precise since associated with ICD implantation or not.

Lack of Early Etiologic Investigations in Young Sudden Cardiac Death

BACKGROUND

Since majority of sudden cardiac arrest (SCA) victims die in the intensive care unit (ICU), early etiologic investigations may improve understanding of SCA and targeted prevention.

METHODS

In this prospective, population-based registry all SCA admitted alive across the 48 hospitals of the Paris area were enrolled. We investigated the extent of early etiologic work-up among young SCD cases (<45 years) eventually dying within the ICU.

RESULTS

From May 2011 to May 2018, 4,314 SCA patients were admitted alive. Among them, 3,044 died in ICU, including 484 (15.9%) young patients. SCA etiology was established in 233 (48.1%) and remained unexplained in 251 (51.9%). Among unexplained (compared to explained) cases, coronary angiography (17.9 vs. 49.4%, P<0.001), computed tomography scan (24.7 vs. 46.8%, P<0.001) and trans-thoracic echocardiography (31.1 vs. 56.7%, P<0.001) were less frequently performed. Only 22 (8.8%) patients with unexplained SCD underwent all three investigations. SCDs with unexplained status decreased significantly over the 7 years of the study period (from 62.9 to 35.2%, P=0.005). While specialized TTE and CT scan performances have increased significantly, performance of early coronary angiography did not change. Autopsy, genetic analysis and family screening were performed in only 48 (9.9%), 5 (1.0%) and 14 cases (2.9%) respectively.

CONCLUSIONS

More than half of young SCD dying in ICU remained etiologically unexplained; this was associated with a lack of early investigations. Improving early diagnosis may enhance both SCA understanding and prevention, including for relatives. Failure to identify familial conditions may result in other preventable deaths within these families.

222AI-based strategy enables faster Holter ECG analysis with equivalent clinical accuracy compared to a classical strategy

BACKGROUND

Analysis of Holter recordings can be challenging and time-consuming, therefore requiring significant clinical resources in order to achieve a high-quality diagnosis. Such resources depend largely on the qualifications of the person conducting the analysis and the duration of the recordings. A novel Holter analysis platform has been developed, based on deep neural networks trained with a dataset of one million ECGs, to allow fast and reliable Holter recording analysis.

PURPOSE

This study sought to compare the performance of an artificial intelligence (AI)-based Holter analysis platform using deep learning tools with a classical one used on a daily basis in hospitals (the reference). The main endpoints evaluated were duration to complete the analysis by the physician operating it as well as diagnostic accuracy of each strategy, when platforms are used by electrophysiologists (EPs).

METHODS

For this prospective evaluation, a total of 159 Holter recordings (24-hour) were selected from a large Holter dataset from 1 hospital, with a relatively high prevalence of electrical rhythm and conduction disorders. Recordings were analysed by four EPs using independently both the AI-based and classical analysis platforms. All four EPs had no previous experience with the AI-based platform, except for an introductory 6-hour training session. Three EPs had multiple years of experience with the traditional platform, while one EP had limited experience. For each recording, in addition to the analysis duration, diagnostic accuracy was evaluated through the analysis of the presence or absence of predefined cardiac arrhythmias and conduction disorders (prevalence): pauses (25.2%), ventricular tachycardia (VT, 30.2%), atrial fibrillation (AF, 26.4%), high grade atrioventricular block (AVB, 10.1%) and burden of premature ventricular complex larger than 10% (PVC, 23.9%). Definite diagnostics were established by an expert EP after a careful examination of all available analysis reports. 

RESULTS

Time required for the AI-based analysis was on average 42% shorter compared to the traditional platform (6.65 min vs 11.5 min, p &lt; 0.0001). Regarding accuracy to detect electrical disorders, there was no statistically significant differences between AI-based and classical platforms (AF: 98.7% vs 96.9%, Pause: 99.4% vs 100%, PVC: 98.7% vs 98.7%, VT: 92.5% vs 96.2%, AVB: 98.7% vs 94.3%). CONCLUSION: These preliminary findings suggest that an AI-based strategy to analyse Holter recordings may be highly accurate in detecting cardiac electrical abnormalities, with significant time savings compared to a classical strategy, even for users with no previous experience with the novel AI-based platform. An AI-based Holter analysis platform may contribute to a broader and more resource-efficient adoption of Holter monitoring.

Abstract Figure. analysis duration using each strategy

Low rates of immediate coronary angiography among young adults resuscitated from sudden cardiac arrest

AIM

Coronary artery disease (CAD) has recently been emphasized as a major cause of sudden cardiac arrest (SCA) in young adults. We aim to assess the rate of immediate coronary angiography performance in young patients resuscitated from SCA.

METHODS

From May 2011 to May 2017, all cases of out-of-hospital SCA aged 18-40 years alive at hospital admission were prospectively included in 48 hospitals of the Great Paris area. Cardiovascular causes of SCA were centrally adjudicated, and management including immediate coronary angiography performance was assessed.

RESULTS

Out of 3579 SCA admitted alive, 409 (11.4%) patients were under 40 years of age (32.3 ± 6.2 years, 69.7% males), with 244 patients having a definite cause identified. Among those, CAD accounted for 72 (29.5%) cases, of which 64 (88.9%) were acute coronary syndromes. The rate of immediate coronary angiography was only 41.7% compared to 65.1% among those ≥40-years (P < 0.001). During the study period, while the rate of immediate coronary angiography increased from 60.5% to 70.3% (P < 0.001) in patients aged ≥40 years, the rate in patients aged less than 40 years remained stable (43.5% to 45.3%, P = 0.795). Patients younger than 40 years were significantly less likely to undergo immediate coronary angiography (OR = 0.34, 95% CI: 0.25-0.47), although early angiography was associated with survival at hospital discharge (OR = 2.68, 95% CI: 1.21-6.00).

CONCLUSION

CAD is the first cause of SCA in young adults aged less than 40 years. The observed low rates of immediate coronary angiography suggest a missed opportunity for early intervention.

[Prevention of sudden cardiac death and implantable cardioverter defibrillators: Understanding the competitive risk!]

Sudden cardiac death represents a major public health issue, with up to 50% of the cardiovascular mortality. Coronary artery disease and dilated cardiomyopathy both represent almost 90% of sudden cardiac death burden. Primary prevention using implantable cardioverter defibrillator relies, in this population, on the left ventricle ejection fraction simple measurement. In this paper, we aim to discuss in which extent a better understanding of competing risk situation may help for a better patient selection and eventually for optimizing primary prevention using implantable cardioverter defibrillator.

P4167Non-shockable rhythm related sudden cardiac arrest in the community

Introduction

A significant increase in the prevalence of sudden cardiac arrest (SCA) with non-shockable rhythm has been reported, related to asystole and pulseless electrical activity (PEA). Factors associated with non-shockable rhythm and the mode to the return of spontaneous circulation (ROSC) may help for a better understanding.

Purpose

We aimed to describe the frequency, characteristics and outcome of SCA related to non-shockable versus shockable rhythm in the community.

Methods

In this prospective ongoing, multicentre population-based registry (6.7 million inhabitants), data from all SCA over a 5-year period were analyzed. Initial rhythm was obtained from the EMS report and the initial recorded rhythm strip when available. Medical records for each SCA were reviewed by cardiologists to identify underlying aetiology and associated conditions.

Results

Among the 3,028 SCAs admitted alive out of a total of 18,622 out-of-hospital cardiac arrests from May 2011 to May 2016, 2,904 patients had available information regarding initial rhythm at the time of EMS arrival. Among them, 1,314 patients (45.3%) presented with non-shockable rhythm: 1,109 (38.2%) cases with asystole, 197 (6.8%) with PEA and 8 (0.3%) with high degree atrioventricular block.

Cases with non-shockable rhythm were older (60.6 vs. 57.4 years, P<0.001), with greater proportion of females (34.9 vs. 19.2%, P<0.001) and less proportion of family history of coronary artery disease or SCA. Proportion of warning symptoms prior to the SCA was higher among patients with non-shockable rhythm (74.3 vs. 64.9%, P<0.001) but the proportion of chest pain was lower (24.0 vs. 43.3%, P<0.001). Survival rate was much lower in non-shockable rhythm cases (7.2 vs. 42.3%, P<0.001).

Among the 1,314 non-shockable cases eventually admitted alive to hospital, 1,022 (77.8%) did not require external defibrillation prior to ROSC, and a majority (91.7%) received adrenaline during resuscitation. In this subgroup, the main identified cardiac cause was acute coronary syndrome (45.3%), followed by chronic CAD (27.1%), structural non-ischemic heart disease (22.4%), and non-structural heart disease (5.2%).

Conclusions

Initial non-shockable rhythm is encountered in almost half of SCA cases admitted alive; mostly occurs in older patients with higher proportion of females. Over three quarters of these cases did not require external defibrillation prior to ROSC.