The role for ambulatory electrocardiogram monitoring in the diagnosis and prognostication of Brugada syndrome: a sub-study of the Rare Arrhythmia Syndrome Evaluation (RASE) Brugada study

AIMS

Brugada syndrome (BrS) diagnosis and risk stratification rely on the presence of a spontaneous type 1 (spT1) electrocardiogram (ECG) pattern; however, its spontaneous fluctuations may lead to misdiagnosis and risk underestimation. This study aims to assess the role for repeat high precordial lead (HPL) resting and ambulatory ECG monitoring in identifying a spT1, and evaluate its prognostic role.

METHODS AND RESULTS

HPL resting and ambulatory monitoring ECGs of BrS subjects were reviewed retrospectively, and the presence of a spT1 associated with ventricular dysrhythmias and sudden cardiac death (SCD). Three-hundred and fifty-eight subjects (77 with spT1 pattern at presentation, Group 1, and 281 without, Group 2) were included. In total, 1651 resting HPL resting and 621 ambulatory monitoring ECGs were available for review, or adequately described. Over a median follow-up of 72 months (interquartile range - IQR - 75), 42/77 (55%) subjects in Group 1 showed a spT1 in at least one ECG. In Group 2, 36/281 subjects (13%) had a newly detected spT1 (1.9 per 100 person-year) and 23 on an HPL ambulatory recording (8%). Seven previously asymptomatic subjects, five of whom had a spT1 (four at presentation and one at follow-up), experienced arrhythmic events; survival analysis indicated that a spT1, either at presentation or during lifetime, was associated with events. Univariate models showed that a spT1 was consistently associated with increased risk [spT1 at presentation: hazard ratio (HR) 6.3, 95% confidence interval (CI) 1.4-28, P = 0.016; spT1 at follow-up: HR 3.1, 95% CI 1.3-7.2, P = 0.008].

CONCLUSION

Repeated ECG evaluation and HPL ambulatory monitoring are vital in identifying transient spT1 Brugada pattern and its associated risk.

MIRACLE2 Score Compared With Downtime and Current Selection Criterion for Invasive Cardiovascular Therapies After OHCA

BACKGROUND

The MIRACLE2 score is the only risk score that does not incorporate and can be used for selection of therapies after out-of-hospital cardiac arrest (OHCA).

OBJECTIVES

This study sought to compare the discrimination performance of the MIRACLE2 score, downtime, and current randomized controlled trial (RCT) recruitment criteria in predicting poor neurologic outcome after out-of-hospital cardiac arrest (OHCA).

METHODS

We used the EUCAR (European Cardiac Arrest Registry), a retrospective cohort from 6 centers (May 2012-September 2022). The primary outcome was poor neurologic outcome on hospital discharge (cerebral performance category 3-5).

RESULTS

A total of 1,259 patients (total downtime = 25 minutes; IQR: 15-36 minutes) were included in the study. Poor outcome occurred in 41.8% with downtime <30 minutes and in 79.3% for those with downtime >30 minutes. In a multivariable logistic regression analysis, MIRACLE2 had a stronger association with outcome (OR: 2.23; 95% CI: 1.98-2.51; P < 0.0001) than zero flow (OR: 1.07; 95% CI: 1.01-1.13; P = 0.013), low flow (OR: 1.04; 95% CI: 0.99-1.09; P = 0.054), and total downtime (OR: 0.99; 95% CI: 0.95-1.03; P = 0.52). MIRACLE2 had substantially superior discrimination for the primary endpoint (AUC: 0.877; 95% CI: 0.854-0.897) than zero flow (AUC: 0.610; 95% CI: 0.577-0.642), low flow (AUC: 0.725; 95% CI: 0.695-0.754), and total downtime (AUC: 0.732; 95% CI: 0.701-0.760). For those modeled for exclusion from study recruitment, the positive predictive value of MIRACLE2 ≥5 for poor outcome was significantly higher (0.92) than the CULPRIT-SHOCK (Culprit lesion only PCI Versus Multivessel PCI in Cardiogenic Shock) (0.80), EUROSHOCK (Testing the value of Novel Strategy and Its Cost Efficacy In Order to Improve the Poor Outcomes in Cardiogenic Shock) (0.74) and ECLS-SHOCK (Extra-corporeal life support in Cardiogenic shock) criteria (0.81) (P < 0.001).

CONCLUSIONS

The MIRACLE2 score has superior prediction of outcome after OHCA than downtime and higher discrimination of poor outcome than the current RCT recruitment criteria. The potential for the MIRACLE2 score to improve the selection of OHCA patients should be evaluated formally in future RCTs.

The resuscitation status of implantable cardioverter-defibrillator patients according to electronic health records: are we ignoring the device?

Introduction/Background

The Care Quality Commission (CQC) has recently raised concerns around resuscitation decisions in the UK. In our hospital an early resuscitation decision is made on admission, often by junior doctors, and documented in electronic notes. Concerns have been raised about the veracity of these discussions in patients with implantable cardioverter-defibrillators (ICD's). We investigated resuscitation status as documented on the electronic record for our ICD population.

Methods

The ICD database was interrogated in 2020 for patients under current follow-up. Baseline demographics, hospital admissions over the past 5 years and ICD indications were documented from the electronic hospital records. All patients with an electronic do-not-resuscitate (DNR) flag on the electronic system were recorded, as were any documented resuscitation discussions and ICD deactivations between 2015 and 2020. Any patient deaths were recorded and correlated with resuscitation status and ICD status at the time of death.

Results

Six-hundred and thirty-six patients with ICD's (transvenous, subcutaneous and CRT defibrillators) were identified under follow-up for the study period. The mean age of the population was 68 years old. 251 had an ischaemic cardiomyopathy, 209 had dilated cardiomyopathy, 50 prior ventricular fibrillation or tachycardia, 40 hypertrophic cardiomyopathy, 26 ARVC and the rest a channelopathy, congenital heart disease, sarcoidosis or valvular heart disease.

Thirty-seven of the 636 patients were flagged on the electronic record as being not for resuscitation (5.9%). They had a mean age of 79 and 54% had an ischaemic cardiomyopathy. Of these, only 15 (39%) had their ICD deactivated and only 12 of those at the time of the resuscitation decision (32%). 15 of the 37 (39%) patients made DNR have subsequently died. Six of these (40%) had an active ICD at the time of death.

In the 257 patients who had had a hospital admission in the study period, 34 were made not for resuscitation during the admission (13%) of whom 11 had their ICD deactivated at the time of discussion (32%). Patients with a DNR flag and an “active” ICD were contacted about deactivation of their ICD and offered discussion with a cardiologist or specialist nurse about ICD deactivation. Of these 9/27 (33%) stated that they wanted resuscitation and the alert was removed and the ICD kept on, although 3 subsequently had the device deactivated.

Conclusions

In this study the majority of patients with ICD's who were made not for resuscitation on admission to hospital did not have their ICD therapies switched off, therefore putting them at risk of unnecessary ICD shocks. In addition, one third these patients subsequently chose to be for resuscitation after discussion. These complex decisions would be improved with the early involvement of cardiologists and specialist nurses.

Funding Acknowledgement

Type of funding sources: None.