Postoperative Atrial Fibrillation Following Noncardiac Surgery Increases Risk of Stroke

BACKGROUND

New-onset postoperative atrial fibrillation is well recognized to be an adverse prognostic marker in patients undergoing noncardiac surgery. Whether postoperative atrial fibrillation confers an increased risk of stroke remains unclear.

METHODS

A systematic review and meta-analysis was performed to assess the risk of stroke after postoperative atrial fibrillation in noncardiac surgery. MEDLINE, Cochrane, and EMBASE databases were searched for articles published up to May 2019 for studies of patients undergoing noncardiac surgery that reported incidence of new atrial fibrillation and stroke. Event rates from individual studies were pooled and risk ratios (RR) were pooled using a random-effects model.

RESULTS

Fourteen studies of 3,536,291 patients undergoing noncardiac surgery were included in the quantitative analysis (mean follow-up 1.4 ± 1 year). New atrial fibrillation occurred in 26,046 (0.74%), patients with a higher incidence following thoracic surgery. Stroke occurred in 279 (1.5%) and 6199 (0.4%) patients with and without postoperative atrial fibrillation, respectively. On pooled analysis, postoperative atrial fibrillation was associated with a significantly increased risk of stroke (RR 2.51; 95% confidence interval, 1.76-3.59), with moderate heterogeneity. The stroke risk was significantly higher with atrial fibrillation following nonthoracic, compared with thoracic, surgery (RR 3.09 vs RR 1.95; P = .01).

CONCLUSION

New postoperative atrial fibrillation following noncardiac surgery was associated with a 2.5-fold increase in the risk of stroke. This risk was highest among patients undergoing nonthoracic noncardiac surgery. Given the documented efficacy of newer anticoagulants, randomized controlled trials are warranted to assess whether they can reduce the risk of stroke in these patients.

Prognostic significance of suboptimal secondary prevention pharmacotherapy after acute coronary syndromes

BACKGROUND

Optimal secondary prevention pharmacotherapy is the cornerstone of post-acute coronary syndrome (ACS) management. The prognostic impact of not receiving five guideline-recommended therapies is poorly described.

AIM

To ascertain the prognostic significance of suboptimal pharmacotherapy in ACS survivors.

METHODS

Consecutive patients with ACS from the Melbourne Interventional Group registry who were alive at 30 days following their index percutaneous coronary intervention were included. Patients were divided into three categories based on the number of secondary prevention medications prescribed. The optimal medical therapy (OMT), near-optimal medical therapy (NMT), suboptimal medical therapy (SMT) groups were prescribed 5, 4 and ≤ 3 medications, respectively. Primary endpoint was long-term mortality. Cox-proportional hazard modelling was undertaken to assess independent predictors of survival.

RESULTS

Of the 9375 patients included, 5678 (60.6%) received OMT, 2903 (31.0%) received NMT and 794 (8.5%) received SMT. Patients receiving SMT were older, more likely to be female and had higher burden of comorbidities (renal impairment, congestive heart failure, diabetes, peripheral vascular disease; P < 0.01 for all). SMT was associated with higher long-term mortality at 3.9 ± 2.2 years when compared to NMT and OMT (16.8% vs 10.5% vs 8.2%, P < 0.001). Compared to OMT, SMT was an independent predictor of long-term mortality (hazard ratio, HR 1.62, 95% confidence interval, CI 1.30-2.02, P < 0.01) while NMT was associated with a clinically significant 14% mortality hazard (HR 1.14, 95% CI 0.97-1.34, P = 0.11).

CONCLUSIONS

There is a graded long-term hazard associated with not receiving OMT after an ACS. Improvements in secondary prevention pharmacotherapy models of care are warranted to further decrease the long-term mortality.

Prospective Evaluation of the Utility of Whole Exome Sequencing in Dilated Cardiomyopathy

Background Dilated cardiomyopathy may be heritable but shows extensive genetic heterogeneity. The utility of whole exome sequencing as a first-line genetic test for patients with dilated cardiomyopathy in a contemporary "real-world" setting has not been specifically established. Using whole exome sequencing with rigorous, evidence-based variant interpretation, we aimed to identify the prevalence of a molecular diagnosis in patients with dilated cardiomyopathy in a clinical setting. Methods and Results Whole exome sequencing was performed in eligible patients (n=83) with idiopathic or familial dilated cardiomyopathy. Variants were prioritized for curation in up to 247 genes and classified using American College of Medical Genetics and Genomics-based criteria. Ten (12%) had a pathogenic or likely pathogenic variant. Eight (10%) participants had truncating TTN variants classified as variants of uncertain significance. Five (6%) participants had variants of unknown significance according to strict American College of Medical Genetics and Genomics criteria but classified as either pathogenic or likely pathogenic by other clinical laboratories. Pathogenic or likely pathogenic variants were found in 8 genes (all within tier 1 genes), 2 (20%) of which are not included in a standard commercially available dilated cardiomyopathy panel. Using our bioinformatics pipeline, there was an average of 0.74 variants of uncertain significance per case with ≈0.75 person-hours needed to interpret each of these variants. Conclusions Whole exome sequencing is an effective diagnostic tool for patients with dilated cardiomyopathy. With stringent classification using American College of Medical Genetics and Genomics criteria, the rate of detection of pathogenic variants is lower than previous reports. Efforts to improve adherence to these guidelines will be important to prevent erroneous misclassification of nonpathogenic variants in dilated cardiomyopathy genetic testing and inappropriate cascade screening.

Frontline barriers to effective paramedic and emergency nursing STEMI management: clinician perspectives

BACKGROUND

Factors that hinder the pivotal role frontline clinicians play in STEMI management are under-reported. We aimed to explore perceived barriers to effective STEMI management by addressing the following questions: 1. What are the most commonly occurring barriers to timely STEMI management for paramedics and emergency nurses? 2. Are there differences in barriers experienced by paramedics and emergency nurses? 3. Are there differences in barriers experienced by frontline clinicians in rural and metropolitan settings?

METHODS

A 79-item online survey was offered to paramedics and emergency nurses. Descriptive statistics and exploratory factor analysis identified the most frequently experienced types of barriers. Professional groups and geographical locations were compared.

RESULTS

There were 333 respondents. Response rates for paramedics was 10% and 9% for members of an emergency nursing association. Most commonly occurring barriers across all respondents were: 'lack of skills development'; 'lack of feedback'; 'untimely support'; 'distance to scene/hospital facilities'; 'hospital-related delays'. Statistically significant differences were found by professional group and geographical location.

CONCLUSION

Barriers to timely management were present, but not frequently experienced. Survey responses indicate a need for improved continuing professional development opportunity, clearer feedback mechanisms, streamlined facilitation of STEMI processes in hospitals, and enhanced access to expert advice/resources for all frontline clinicians.

Predictors of ManuScript Rejection sYndrome (MiSeRY): a cohort study

OBJECTIVES

To assess whether specific factors predict the development of ManuScript Rejection sYndrome (MiSeRY) in academic physicians.

DESIGN

Prospective pilot study; participants self-administered a questionnaire about full manuscript submissions (as first or senior author) rejected at least once during the past 5 years.

SETTING

Single centre (tertiary institution).

PARTICIPANTS

Eight academic physician-authors.

MAIN OUTCOME MEASURES

Duration of grief. MiSeRY was pre-specified as prolonged grief (grief duration longer than the population median).

RESULTS

Eight participants provided data on 32 manuscripts with a total of 93 rejections (median, two rejections per manuscript; interquartile range [IQR], 1-3 rejections per manuscript). Median age at rejection was 37 years (IQR, 33-45 years); 86% of 80 rejections involved male authors (86%), 56 of the authors providing data about these rejections were first authors (60%). The median journal impact factor was 5.9 (IQR, 5.2-17). In 48 cases of rejection (52%), pre-submission expectations of success had been high, and in 54 cases (58%) the manuscripts had been sent for external review. Median grief duration was 3 hours (IQR, 1-24 h). Multivariate analysis indicated that higher pre-submission expectation (adjusted odds ratio [aOR], 5.0; 95% CI, 1.5-18), first author status (aOR, 9.5; 95% CI, 1.1-77), and external review (aOR, 19.0; 95% CI 2.9-126) were independent predictors of MiSeRY.

CONCLUSIONS

To help put authors out of their MiSeRY, journal editors could be more selective in the manuscripts they send for external review. Tempering pre-submission expectations and mastering the Coping and reLaxing Mechanisms (CaLM) of senior colleagues are important considerations for junior researchers.

Accuracy of wrist-worn heart rate monitors for rate control assessment in atrial fibrillation

BACKGROUND

Wrist-worn heart rate (HR) monitors are increasingly popular. A paucity of data exists on their accuracy in atrial fibrillation (AF) in ambulatory patients. We sought to assess the HR accuracy of two commercially available smart watches [SW] (Fitbit Charge HR [FB] and Apple Watch Series 3 [AW]) compared with Holter monitoring in an ambulant patient cohort.

METHODS

Thirty-two participants ≥18 years referred for 24-hour Holter monitoring were prospectively recruited. Each participant was randomly allocated to wear either a FB or AW along with their Holter monitor.

RESULTS

Across all devices, 53,288 heart rate values were analysed from 32 participants. Twenty wore the AW (17 had persistent AF and 3 had sinus rhythm [SR]) while 12 participants wore the FB (9 in persistent AF and 3 in SR). Participants in SR demonstrated strong agreement compared to Holter monitoring (bias <1 beat, limits of agreement [LoA] -11 to 11 beats). In AF, both devices underestimated HR measurements (bias -9 beats, LoA -41 to 23). The degree of underestimation was more pronounced when HR > 100 bpm (bias of -28 beats for HR range 100-120 bpm, -48 for 120-140 bpm, and -69 for >140 bpm) compared to a slower HR (bias of -6 for HR range 80-100 bpm, <1 for 60-80 bpm, and -1 for <60 bpm).

CONCLUSION

In ambulatory patients, smartwatches underestimated HR in AF particularly at HR ranges >100 bpm. Further improvements in device technology are needed before integrating them into the clinical management of rate control in AF.

Mitral Valve Prolapse and Sudden Cardiac Death: A Systematic Review

Background

The relationship between mitral valve prolapse (MVP) and sudden cardiac death (SCD) remains controversial. In this systematic review, we evaluate the relationship between isolated MVP and SCD to better define a potential high‐risk subtype. In addition, we determine whether premortem parameters could predict SCD in patients with MVP and the incidence of SCD in MVP.

Methods and Results

Electronic searches were conducted in PubMed and Embase for all English literature articles published between 1960 and 2018 regarding MVP and SCD or cardiac arrest. We also identified articles investigating predictors of ventricular arrhythmias or SCD and cohort studies reporting SCD outcomes in MVP. From 2180 citations, there were 79 articles describing 161 cases of MVP with SCD or cardiac arrest. The median age was 30 years and 69% of cases were female. Cardiac arrest occurred during situations of stress in 47% and was caused by ventricular fibrillation in 81%. Premature ventricular complexes on Holter monitoring (92%) were common. Most cases had bileaflet involvement (70%) with redundancy (99%) and nonsevere mitral regurgitation (83%). From 22 articles describing predictors for ventricular arrhythmias or SCD in MVP, leaflet redundancy was the only independent predictor of SCD. The incidence of SCD with MVP was estimated at 217 events per 100 000 person‐years.

Conclusions

Isolated MVP and SCD predominantly affects young females with redundant bileaflet prolapse, with cardiac arrest usually occurring as a result of ventricular arrhythmias. To better understand the complex relationship between MVP and SCD, standardized reporting of clinical, electrophysiological, and cardiac imaging parameters with longitudinal follow‐up is required.

Plasma ACE2 Activity Predicts Mortality in Aortic Stenosis and Is Associated With Severe Myocardial Fibrosis

OBJECTIVES

This study investigated the relationship between plasma angiotensin-converting enzyme 2 (ACE2) activity levels and the severity of stenosis and myocardial remodeling in patients with aortic stenosis (AS) and determined if plasma ACE2 levels offered incremental prognostic usefulness to predict all-cause mortality.

BACKGROUND

ACE2 is an integral membrane protein that degrades angiotensin II and has an emerging role as a circulating biomarker of cardiovascular disease.

METHODS

Plasma ACE2 activity was measured in 127 patients with AS; a subgroup had myocardial tissue collected at the time of aortic valve replacement.

RESULTS

The median plasma ACE2 activity was 34.0 pmol/ml/min, and levels correlated with increased valvular calcification (p = 0.023) and the left ventricular (LV) mass index (r = 0.34; p < 0.001). Patients with above-median plasma ACE2 had higher LV end-diastolic volume (57 ml/m² vs. 48 ml/m²; p = 0.021). Over a median follow-up of 5 years, elevated plasma ACE2 activity was an independent predictor of all-cause mortality after adjustment for relevant clinical, imaging, and biochemical parameters (HR: 2.28; 95% CI: 1.03 to 5.06; p = 0.042), including brain natriuretic peptide activation (integrated discrimination improvement: 0.08; p < 0.001). In 22 patients with plasma and tissue, increased circulating ACE2 was associated with reduced myocardial ACE2 gene expression (0.7-fold; p = 0.033) and severe myocardial fibrosis (p = 0.027).

CONCLUSIONS

In patients with AS, elevated plasma ACE2 was a marker of myocardial structural abnormalities and an independent predictor of mortality with incremental value over traditional prognostic markers. Loss of ACE2 from the myocardium was associated with increased fibrosis and higher circulating ACE2 levels.

P574Accuracy of wrist-worn heart rate monitors for chronotropic assessment in atrial fibrillation

Introduction

Wrist-worn fitness and heart rate (HR) monitors are increasingly popular. Previous studies in healthy participants with sinus rhythm (SR) have yielded variable results depending on HR, activity levels and device tested. A paucity of data exists on their accuracy in atrial fibrillation (AF) in ambulatory patients.

Purpose

We sought to assess the HR accuracy of 2 commercially available smart watches (Fitbit Charge HR [FB] and Apple Watch Series 3 [AW]) compared with Holter monitoring in an ambulant patient cohort.

Methods

Patients aged >18 years referred for 24-hour Holter monitoring were prospectively recruited. The Holter monitor was the criterion measure. Each patient was randomly allocated to either a FB or AW along with their Holter monitor. The study protocol was approved by the institutional review board.

Statistical analysis: Pearson (r) correlation coefficients and Bland-Altman comparison with 95% limits of agreement (LoA) were evaluated to assess criterion validity and agreement between the smart watch and Holter ECG-HR. Bias was the calculated mean difference between the smart watch and ECG-HR. A ± 10-beat different between Holter-HR and SW-HR was used as a clinically relevant range to establish the accuracy of HR estimation by SW.

Results

Across all devices, 53,288 hear rate values were recorded from 32 patients. Twenty six patients were in persistent AF and six were in SR. Twelve patients wore the FB while 20 wore the AW. In the FB arm, nice patient were in persistent AF and three in SR. In the AW arm, persistent AF was the rhythm in seventeen and SR in three. Patients in SR demonstrated overall strong agreement compared to Holter monitoring (Mean Bias <1 beat, LoA −11 to 11 beats) and a correlation coefficient of 0.87 (p<0.001). In AF, both devices underestimated HR measurements (Overall Bias −9 beats, LoA −41 to 23, r=0.60, p<0.001). The AW had lower bias and narrower LoA compared to FB (−5 beats vs −13 beats, LoA −31 to 21 beats vs −50 to 22 beats). Using a ± 10-beat range against ECG-HR for clinical accuracy, both the AW and FB performed satisfactorily in SR with 95.2% of AW and 92.2% of FB HR readings considered valid. In AF, however, the AW-HR readings were within the ± 10-beat threshold in 76.5% of the time compared with only 56.1% of FB readings.

Conclusion

In ambulatory patients, smart watches were accurate in HR estimation when compared to Holter monitor in SR; however tended to underestimate HR in AF. Further improvements in device technology are needed before the widespread consumer adoption of this nascent technology for chronotropic assessment in arrhythmias.