Atrial fibrillation during acute myocardial infarction: association with all-cause mortality and sudden death after 7-year of follow-up

Early inhibition of the ATM/p53 pathway reduces the susceptibility to atrial fibrillation and atrial remodeling following acute myocardial infarction

Atrial fibrillation (AF) emerges as a critical complication following acute myocardial infarction (AMI) and is associated with a significant increased risk of heart failure, stroke and mortality. Ataxia telangiectasia mutated (ATM), a key player in DNA damage repair (DDR), has been implicated in multiple cardiovascular conditions, however, its involvement in the development of AF following AMI remains unexplored. This study seeks to clarify the contribution of the ATM/p53 pathway in the onset of AF post-AMI and to investigate the underlying mechanisms. The rat model of AMI was established by ligating left anterior descending coronary artery in the presence or absence of Ku55933 (an ATM kinase inhibitor, 5 mg/kg/d) treatment. Rats receiving Ku55933 were further divided into the early administration group (administered on days 1, 2, 4, and 7 post-AMI) and the late administration group (administered on days 8, 9, 11 and 14 post-AMI). RNA-sequencing was performed 14 days post-operation. In vitro, H2O2-challenged HL-1 atrial muscle cells were utilized to evaluate the potential effects of different ATM inhibition schemes, including earlier, middle, and late periods of intervention. Fourteen days post-AMI injury, the animals exhibited significantly increased AF inducibility, exacerbated atrial electrical/structural remodeling, reduced ventricular function and exacerbated atrial DNA damage, as evidenced by enhanced ATM/p53 signaling as well as γH2AX level. These effects were partially consistent with the enrichment results of bioinformatics analysis. Notably, the deleterious effects were ameliorated by early, but not late, administration of Ku55933. Mechanistically, inhibition of ATM signaling successfully suppressed atrial NLRP3 inflammasome-mediated pyroptotic pathway. Additionally, the results were validated in the in vitro experiments demonstrating that early inhibition of Ku55933 not only attenuated cellular ATM/p53 signaling, but also mitigated inflammatory response by reducing NLRP3 activation. Collectively, hyperactivation of ATM/p53 contributed to the pathogenesis of AF following AMI. Early intervention with ATM inhibitors substantially mitigated AF susceptibility and atrial electrical/structural remodeling, highlighting a novel therapeutic avenue against cardiac arrhythmia following AMI.

The relationship between atrial fibrillation and coronary artery disease: Understanding common denominators

Atrial fibrillation (AF) and coronary artery disease (CAD) are highly prevalent cardiovascular conditions. The coexistence of both diseases is common as they share similar risk factors and common pathophysiological characteristics. Systemic inflammatory conditions are associated with an increased incidence of both AF and CAD. The presence of both entities increases the incidence of complications and adverse outcomes. Furthermore, their coexistence poses challenges for the management of patients, particularly with respect to anticoagulation and rhythm management. In this review, we aim to better understand the relationship between AF and CAD by detailing basic molecular pathophysiology, assessing therapeutic guidelines, and describing interactions between the two conditions.

USP38 exacerbates atrial inflammation, fibrosis, and susceptibility to atrial fibrillation after myocardial infarction in mice

BACKGROUND

Inflammation plays an important role in the pathogenesis of atrial fibrillation (AF) after myocardial infarction (MI). The role of USP38, a member of the ubiquitin-specific protease family, on MI-induced atrial inflammation, fibrosis, and associated AF is unclear.

METHODS

In this study, we surgically constructed a mouse MI model using USP38 cardiac conditional knockout (USP38-CKO) and cardiac-specific overexpression (USP38-TG) mice and applied biochemical, histological, electrophysiological characterization and molecular biology to investigate the effects of USP38 on atrial inflammation, fibrosis, and AF and its mechanisms.

RESULTS

Our results revealed that USP38-CKO attenuates atrial inflammation, thereby ameliorating fibrosis, and abnormal electrophysiologic properties, and reducing susceptibility to AF on day 7 after MI. USP38-TG showed the opposite effect. Mechanistically, The TAK1/NF-κB signaling pathway in the atria was significantly activated after MI, and phosphorylated TAK1, P65, and IκBα protein expression was significantly upregulated. USP38-CKO inhibited the activation of the TAK1/NF-κB signaling pathway, whereas USP38-TG overactivated the TAK1/NF-κB signaling pathway after MI. USP38 is dependent on the TAK1/NF-κB signaling pathway and regulates atrial inflammation, fibrosis, and arrhythmias after MI to some extent.

CONCLUSIONS

USP38 plays an important role in atrial inflammation, fibrosis, and AF susceptibility after MI, providing a promising target for the treatment of AF after MI.

Association of atrial depolarization variability and cardiac autonomic regulation with sudden cardiac death in coronary artery disease

AIMS

To evaluate the prognostic significance of the temporal variability of P-wave morphology, specifically in relation to cardiac autonomic regulation.

METHODS AND RESULTS

We analyzed the standard deviation of P-wave residuum (PWRSD) from five consecutive beats of the standard 12-lead ECG in 1236 patients with angiographically verified coronary artery disease (CAD). We evaluated the prognostic value of PWRSD, of PWRSD and PWR in relation to the 24 h standard deviation of normal-to-normal intervals (PWRSD/SDNN and PWR/SDNN). After 8.7 ± 2.2 years of follow-up on average, 43 patients (3.5%) experienced sudden cardiac death (SCD) or were resuscitated from sudden cardiac arrest (SCA), 34 (2.8%) succumbed to non-sudden cardiac death (NSCD) and 113 (9.1%) to non-cardiac death (NCD). In the Cox regression analysis, PWRSD (≥0.002727) had a significant univariate (uv) [hazard ratio (HR): 4.27, 95% confidence interval (CI): 2.26-8.08, P = 0.000008] and multivariate (mv) (HR: 2.58, 95% CI: 1.31-5.08, P = 0.006) association with SCD/SCA but not with NSCD (uv P = 0.76, mv P = 0.33) or NCD (uv P = 0.57, mv P = 0.66). All the studied P-morphology parameters retained a significant association with the risk of SCD/SCA after relevant adjustment (mv P-values from 0.00003 to <0.05) but not with NSCD or NCD. When dichotomized PWRSD, PWR, PWRSD/SDNN, and PWR/SDNN were added to the clinical risk model for SCD/SCD, the C-index increased from 0.799 to 0.834 and integrated discrimination index and net reclassification index improved significantly (P < 0.001).

CONCLUSION

Variability of P-morphology representing temporo-spatial heterogeneity of atrial depolarization, specifically when combined with cardiac autonomic regulation, independently predicts the risk of SCD in patients with CAD.

Impact of atrial fibrillation and the clinical outcomes in patients with acute myocardial infarction from the K-ACTIVE registry

BACKGROUND

The clinical incidence and impact of atrial fibrillation (AF) in Japanese acute myocardial infarction (AMI) patients is not fully understood.

METHODS

To elucidate the clinical incidence and impact of AF on in-hospital mortality in AMI patients, we analyzed a Japanese observational prospective multicenter registry of acute myocardial infarction (K-ACTIVE: Kanagawa ACuTe cardIoVascular rEgistry), which spans 2015 to 2019. A major adverse cardiac event (MACE) was defined as cardiovascular death, non-fatal myocardial infarction (MI), and non-fatal stroke. For assessing bleeding events, Bleeding Academic Research Consortium (BARC) type 3 or 5 was used. MACE plus BARC type 3 or 5 bleeding were considered as composite events. The clinical outcomes were followed for 1 year.

RESULTS

The total of 5059 patients included 531 patients with AF (10.5%) and 4528 patients with sinus rhythm (SR; 89.5%). AF patients were significantly older and tended to have more comorbidities than SR patients. Oral anticoagulation therapy (OAC) was used in 44% of AF patients while single antiplatelet therapy was selected for 52% of patients with OAC. Crude in-hospital mortality was significantly greater in AF patients than in SR patients (10.4%, 5.0%, respectively, p < 0.01). The multivariate analysis was adjusted for age, sex, diabetes, hypertension, hemodialysis, smoking, previous MI, body mass index, Killip classification, out of hospital cardiac arrest, and OAC. In-hospital mortality was still significantly greater in AF patients than in SR patients in the logistic regression analysis [adjusted odds ratio 2.02 (1.31-3.14)]. AF was an independent risk factor for MACE and composite events in the Cox proportional hazards model [adjusted risk ratio (ARR) 1.91 (1.36-2.69), p < 0.01; ARR 1.72 (1.25-2.36), p < 0.01]. In contrast, AF was not an independent risk factor for bleeding [ARR 1.71 (0.79-3.71), p = 0.18].

CONCLUSION

In Japanese AMI patients, AF was often observed and was associated with worse MACE but not worse bleeding.

Digital Predictors of Morbidity, Hospitalization, and Mortality Among Older Adults: A Systematic Review and Meta-Analysis

The widespread adoption of digital health technologies such as smartphone-based mobile applications, wearable activity trackers and Internet of Things systems has rapidly enabled new opportunities for predictive health monitoring. Leveraging digital health tools to track parameters relevant to human health is particularly important for the older segments of the population as old age is associated with multimorbidity and higher care needs. In order to assess the potential of these digital health technologies to improve health outcomes, it is paramount to investigate which digitally measurable parameters can effectively improve health outcomes among the elderly population. Currently, there is a lack of systematic evidence on this topic due to the inherent heterogeneity of the digital health domain and the lack of clinical validation of both novel prototypes and marketed devices. For this reason, the aim of the current study is to synthesize and systematically analyse which digitally measurable data may be effectively collected through digital health devices to improve health outcomes for older people. Using a modified PICO process and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) framework, we provide the results of a systematic review and subsequent meta-analysis of digitally measurable predictors of morbidity, hospitalization, and mortality among older adults aged 65 or older. These findings can inform both technology developers and clinicians involved in the design, development and clinical implementation of digital health technologies for elderly citizens.

Applying the CHA2DS2-VASc score to predict the risk of future acute coronary syndrome in patients receiving catheter ablation for atrial fibrillation

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AF patients without catheter ablation have a higher risk of future ACS when compared to normal control group.

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The presence of AF without catheter ablation is an independent risk factor for future acute coronary events.

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Catheter ablation to AF could reduce future risk of acute coronary events over a very long-term follow-up.

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The cut-off value of baseline CHA₂DS₂-VASc score ≥ 4 can strongly predict future acute coronary events in patients with AF.

Objective

It remains unknown whether catheter ablation for atrial fibrillation (AF) reduces future acute coronary syndrome (ACS) risk or whether the CHA₂DS₂-VASc score has a role in predicting this risk. We aimed to compare very long-term risk of ACS between patients who received catheter ablation to AF or antiarrhythmic medications and controls without AF.

Methods

Propensity scores were calculated for each patient and used to assemble a cohort of 787 patients undergoing AF ablation in 2003–2012. Patients were compared to an equal number of AF patients treated with antiarrhythmic medications and a control group without AF. Patients with previous coronary events were excluded. The primary endpoint was ACS occurrence.

Results

Baseline clinical characteristics were comparable. After a mean 9.1 ± 3.2-year follow-up, the ablation group had lower incidence of new onset ACS than the medication and non-AF control groups (annual incidence: 0.15%. 0.78%, and 0.35%; with 2.67, 4.16, and 10.44 cases/1000 person-years, respectively; P < 0.001). After adjusting for multiple confounders, the ablation group had lower future ACS risk than the medication (hazard ratio [HR]: 0.20, 95% confidence interval [CI]: 0.13–0.30) and control groups (HR: 0.30, 95% CI: 0.20–0.45). The CHA₂DS₂-VASc score was a strong predictor of ACS (HR: 1.61, 95% CI: 1.47–1.76; AUC: 85.9%, 95% CI: 78.5–93.2%). A baseline CHA₂DS₂-VASc score ≥ 4 predicted future ACS (positive predictive rate: 14.3%).

Conclusions

This study suggested that catheter ablation for AF may be beneficial to reduce future ACS risk in AF patients, and a high baseline CHA₂DS₂-VASc score can predict future acute coronary events.

Epidemiology of Atrial Fibrillation in the 21st Century: Novel Methods and New Insights

Accompanying the aging of populations worldwide, and increased survival with chronic diseases, the incidence and prevalence of atrial fibrillation (AF) are rising, justifying the term global epidemic. This multifactorial arrhythmia is intertwined with common concomitant cardiovascular diseases, which share classical cardiovascular risk factors. Targeted prevention programs are largely missing. Prevention needs to start at an early age with primordial interventions at the population level. The public health dimension of AF motivates research in modifiable AF risk factors and improved precision in AF prediction and management. In this review, we summarize current knowledge in an attempt to untangle these multifaceted associations from an epidemiological perspective. We discuss disease trends, preventive opportunities offered by underlying risk factors and concomitant disorders, current developments in diagnosis and risk prediction, and prognostic implications of AF and its complications. Finally, we review current technological (eg, eHealth) and methodological (artificial intelligence) advances and their relevance for future prevention and disease management.

[Specific Features of the Course of Acute Coronary Syndrome in Patients with Newly Developed Atrial Fibrillation in Clinical Practice According to the Data of the Register of Acute Coronary Syndrome]

AIM

to elucidate risk factors of development of atrial fibrillation (AF) in patients with acute coronary syndrome (ACS), and to assess of patient's adherence to oral anticoagulant therapy (OAT) during 12 months after ACS episode according to the data of the Total ACS Registry for the Krasnodar Territory.

MATERIALS AND METHODS

In this retrospective analysis we used Registry data on patients with ACS and concomitant AF, consecutively admitted to cardiological departments of the S.V. Ochapovsky Territorial Clinical Hospital from 20/11/2015 to 20/02/18. Number of patients in the analyzed group was 201 (52 with AF which first appeared in connection with the index ACS). Survivors after hospital discharge were contacted by telephone and at planned visits. The analysis included assessment of rates of the following outcomes: inhospital death, hemorrhagic and thromboembolic complications, prognostic efficacy of the CRISADE and HAS BLED scores, and expediency of prescription to patients with ACS and concomitant first AF episode of prolonged OAT after hospital discharge.

RESULTS

Demographic and anamnestic data of patients with the first AF attack at the background of ACS were like those of patients with other types of AF. This group of patients was characterized by more severe course of the disease, but this produced no impact on inhospital mortality and rate of complications, as well as on mortality for 12 months after hospital discharge.

CONCLUSION

The results of this analysis are important for understanding distinctive characteristics of patients with AF first developed during ACS.

Prognostic significance of P-wave morphology in patients with coronary artery disease

INTRODUCTION

The prognostic significance of P-wave morphology in patients with coronary artery disease (CAD) is not well-known.

METHODS

A total of 1946 patients with angiographically verified CAD were included in the Innovation to reduce Cardiovascular Complications of Diabetes at the Intersection (ARTEMIS) study. The P-wave morphology could be analyzed in 1797 patients.

RESULTS

During 7.4 ± 2.0 years, a total of 168 (9.3%) patients died or experienced resuscitation from sudden cardiac arrest (SCA), 43 (2.4%) patients experienced sudden cardiac death (SCD) or were resuscitated from SCA, 37 (2.1%) patients succumbed to non-SCD (NSCD), and 88 (4.9%) patients to noncardiac death (NCD). Of the P-wave parameters, the absolute P-wave residuum (PWR), the heterogeneity of the P-wave morphology (PWH), and the P-wave duration (Pdur) had the closest univariate association with the risk of SCD/SCA (0.0038 ± 0.0026 vs 0.0022 ± 0.0017, P < .001; 11.0 ± 5.2 vs 8.6 ± 3.6, P < .01; 142.7 ± 16.9 vs 134.8 ± 14.3 milliseconds, P < .01; SCD/SCA vs no SCD/SCA, respectively). After adjustments with factors that were associated with the risk of SCD/SCA, such as diabetes, smoking, left bundle branch block, high-sensitivity C-reactive protein, and high-sensitivity troponin T, PWR (P < .001), PWH (P < .05), and Pdur (P < 0.01) still predicted SCD/SCA but not non-sudden cardiac death. When these parameters were added to the SCD/SCA clinical risk model, the discrimination and reclassification accuracy of the risk model increased significantly (P < .05, P < .001) and the C-index increased from 0.745 to 0.787.

CONCLUSION

The P-wave morphology parameters independently predict SCD/SCA in patients with CAD.

The imminent epidemic of atrial fibrillation and its concomitant diseases - Myocardial infarction and heart failure - A cause for concern

Atrial fibrillation (AF) is increasingly common in the general population. It often coincides with myocardial infarction (MI) and heart failure (HF) which are also diseases in older adults. All three conditions share common cardiovascular risk factors. While hypertension and obesity are central risk factors for all three diseases, smoking and diabetes appear to have less impact on AF. To date, age is the single most important risk factor for AF in the general population. Further, epidemiological studies suggest a strong association of AF to MI and HF. The underlying pathophysiological mechanisms are complex and not fully understood. Both MI and HF can trigger development of AF, mainly by promoting structural and electrical atrial remodeling. On the other hand, AF facilitates HF and MI development via multiple mechanisms, resulting in a vicious circle of cardiac impairment and adverse cardiovascular prognosis. Consequently, to prevent and treat the coincidence of AF and HF or MI a strict optimization of cardiovascular risk factors is required.

Sudden Cardiac Death in Dialysis: Arrhythmic Mechanisms and the Value of Non-invasive Electrophysiology

Sudden Cardiac Death (SCD) is the leading cause of cardiovascular death in dialysis patients. This review discusses potential underlying arrhythmic mechanisms of SCD in the dialysis population. It examines recent evidence from studies using implantable loop recorders and from electrophysiological studies in experimental animal models of chronic kidney disease. The review summarizes advances in the field of non-invasive electrophysiology for risk prediction in dialysis patients focusing on the predictive value of the QRS-T angle and of the assessments of autonomic imbalance by means of heart rate variability analysis. Future research directions in non-invasive electrophysiology are identified to advance the understanding of the arrhythmic mechanisms. A suggestion is made of incorporation of non-invasive electrophysiology procedures into clinical practice. Key Concepts: - Large prospective studies in dialysis patients with continuous ECG monitoring are required to clarify the underlying arrhythmic mechanisms of SCD in dialysis patients. - Obstructive sleep apnoea may be associated with brady-arrhythmias in dialysis patients. Studies are needed to elucidate the burden and impact of sleeping disorders on arrhythmic complications in dialysis patients. - The QRS-T angle has the potential to be used as a descriptor of uremic cardiomyopathy. - The QRS-T angle can be calculated from routine collected surface ECGs. Multicenter collaboration is required to establish best methodological approach and normal values. - Heart Rate Variability provides indirect assessment of cardiac modulation that may be relevant for cardiac risk prediction in dialysis patients. Short-term recordings with autonomic provocations are likely to overcome the limitations of out of hospital 24-h recordings and should be prospectively assessed.

Arterial hypertension and atrial fibrillation: standard and advanced echocardiography from diagnosis to prognostication

: Structural changes in left and right cardiac chambers that occur in arterial hypertension (AH) may lead to an increased risk of atrial fibrillation. Considering that AH is currently the most common cardiovascular disease in the general population, it represents a major risk factor for atrial fibrillation development. This review explores the complex relationship between atrial fibrillation and AH, starting from its pathophysiological basis. It focuses on the role of echocardiography in the management of hypertensive and atrial fibrillation patients, with emphasis on what should be evaluated about left ventricular remodeling, diastolic and systolic function, left atrial (LA) size and function and right ventricular deformation in patients with AH.

Association of digitalis treatment with outcomes following myocardial infarction in patients with heart failure or evidence of left ventricular dysfunction: an analysis from the High-Risk Myocardial Infarction Database Initiative

BACKGROUND

Contradictory findings have been reported regarding the safety and efficacy of digitalis in patients recovering from acute myocardial infarction (MI). We studied the association of digitalis use with long-term and short-term prognosis in patients presenting with an acute MI complicated with heart failure (HF), left ventricular dysfunction, or both.

METHODS AND RESULTS

Using the High-Risk MI Database Initiative combining data from 4 major clinical trials, totaling 27,673 patients, we investigated the association between digitalis use at baseline (3093 patients with digitalis and 24,580 without) with the rate of all-cause death, sudden cardiac death, cardiovascular death, HF hospitalization and the combination of the latter two, over a mean follow-up time of 2.7 years. Patients with and without atrial fibrillation (AF) were studied separately. After a propensity score-based analysis, among patients without AF, those receiving digitalis experienced a higher rate of all-cause [hazard ratio (HR) 1.54, 95% confidence interval (CI) 1.42-1.67] and sudden cardiac death (HR 1.65, 95% CI 1.44-1.89), compared to those not receiving digitalis; similar results were found for the other 3 endpoints (all HR around 1.6). In contrast, in AF patients, digitalis had a milder effect on all outcomes (all HR ≤ 1.12), with significant association only for the composite endpoint (HR 1.10, 95% CI 1.00-1.21, p = 0.049); comparable results were obtained at 30 days. Finally, the detrimental effect associated with digitalis use appeared to be more pronounced in patients with ejection fraction ≥ 40%.

CONCLUSIONS

In MI survivors with HF and/or systolic dysfunction, digitalis was associated with a significant increased risk of death in patients without AF with mild to neutral associations for patients with AF. These findings raise concerns regarding the safety of digitalis in MI survivors with HF, especially for those without AF.

Dual Antiplatelet Therapy and Outcomes in Patients With Atrial Fibrillation and Acute Coronary Syndromes Managed Medically Without Revascularization: Insights From the TRILOGY ACS Trial

Associations between atrial fibrillation (AF), outcomes, and response to antiplatelet therapies in patients with acute coronary syndrome (ACS) managed medically without revascularization remain uncertain. We examined these associations for medically managed ACS patients randomized to dual antiplatelet therapy (DAPT) using patient data from the TRILOGY ACS trial. DAPT included aspirin plus clopidogrel 75 mg/d or prasugrel 10 mg/d (5 mg/d for those <60 kg or age ≥75 years). Patients receiving oral anticoagulants were excluded. Cox proportional hazards regression modeling was used to characterize associations between patients with AF (AF+) vs those without (AF-) and risk of ischemic and bleeding events, and to explore effects of randomized treatment on outcomes. Among 9101 patients with baseline AF status, 710 (7.8%) had AF. AF+ patients were older and had more comorbidities. Unadjusted associations of the composite of cardiovascular death/myocardial infarction/stroke were significantly higher among AF patients at 30 months (31.1% vs 18.4%; HR: 1.61, 95% CI: 1.35-1.92, P < 0.001), but differences did not persist after adjustment (HR: 1.16, 95% CI: 0.97-1.39, P = 0.11). When individual components of the composite endpoint were evaluated, 30-month risk of events in AF+ patients was significantly higher. Thirty-month risk of all-cause death was significantly higher in AF+ patients: 18.1% vs 11.1% (HR: 1.62, 95% CI: 1.30-2.02, P < 0.001). There was no significant interaction with randomized treatment and AF for the primary endpoint. Among medically managed high-risk ACS patients receiving DAPT, AF was associated with higher unadjusted risks of ischemic and bleeding outcomes that were similar by treatment group.

Clinical features and in-hospital mortality associated with different types of atrial fibrillation in patients with acute coronary syndrome with and without ST elevation

BACKGROUND

In patients with an acute coronary syndrome (ACS), no conclusive agreement has been reached to date regarding the association between the different types of atrial fibrillation (AF) and the in-hospital mortality risk. We conducted a retrospective cohort study in patients with ACS to determine the prognostic implications of the different types of AF.

METHODS

We analyzed 6705 consecutive patients with ACS admitted to a coronary care unit (CCU), including 3094 with ST segment elevation myocardial infarction (STEMI) and 3611 with non-ST-elevation acute coronary syndrome (NSTE-ACS). We identified the patients with pre-existing AF, new-onset AF at admission, and new-onset AF at the CCU.

RESULTS

The overall incidence of AF was documented in 360 (5.4%) of the patients (STEMI, 5%; NSTE-ACS, 5.6%), 140 (2.1%) of whom had pre-existing AF, and 220 (3.2%) of whom had new-onset AF (AF at admission, 1.3%; AF at the CCU, 1.9%). The patients with AF had high-risk clinical characteristics and developed major adverse events more frequently than did the patients without AF. The unadjusted in-hospital mortality risk was significantly higher in the patients with pre-existing AF (STEMI, 3.79-fold; NSTE-ACS, 3.4-fold) and AF at the CCU (STEMI, 2.02-fold; NSTE-ACS, 8.09-fold). After adjusting for the multivariate analysis, only the AF at the CCU in the NSTE-ACS group was associated with a 4.40-fold increase in the in-hospital mortality risk (odds ratio 4.40, CI 1.82-10.60, p=0.001). In the STEMI group, the presence of any type of AF was not associated with an increased risk of mortality.

CONCLUSION

Among the different types of AF in patients with ACS, only the new-onset AF that developed during the CCU stay in patients with NSTE-ACS was associated with a 4.40-fold increase in the in-hospital mortality risk.

Prognostic impact of atrial fibrillation occurrence in patients with non-ST-elevation acute coronary syndromes: is dysrhythmia duration a parameter to focus on?

Several studies have evaluated the prognostic impact of atrial fibrillation (AF) in ST-elevation myocardial infarction (STEMI) patients, but scarce data are available on the role of AF in non-ST-elevation acute coronary syndromes (NSTE-ACS). The aim of this study was to investigate long-term outcome of NSTE-ACS patients experiencing an episode of AF during in-hospital course. Of 1,147 NSTE-ACS patients, 54.4% for non-STEMI (NSTEMI) and 45.6% for unstable angina, 65 (5.7%) had an episode of AF. Long-term survival was compared with that of 1,082 NSTE-ACS patients who did not develop AF. Patients who developed AF, with respect to those who did not, were older and more frequently with NSTEMI at admission (69.2 vs. 53.5%, p = 0.013), diabetes, dyslipidemia and history of heart failure. Moreover, patients who developed AF had a significantly higher New York Heart Association class and lower values of glomerular filtration rate. During a median follow-up of 40.7 months, we observed a significantly higher mortality in NSTE-ACS patients who developed AF versus those who did not (42.2 vs. 19.8%, p < 0.001). AF occurrence in NSTE-ACS was a significant predictor of mortality at Cox regression (adjusted HR: 1.85; p = 0.03). After propensity score analysis, only patients with AF duration >6 h showed a significantly higher mortality at Cox regression (p = 0.021). Our results suggest that NSTE-ACS patients who develop AF are characterized by a higher clinical complexity. The occurrence of AF, when longer than 6 h, represents an important negative prognostic factor for long-term survival.

The association between atrial fibrillation and sudden cardiac death: the relevance of heart failure

OBJECTIVES

The purpose of this study was to evaluate the role of congestive heart failure (CHF) in the association between atrial fibrillation (AF) and sudden cardiac death (SCD).

BACKGROUND

Recent studies have reported the possibility of an independent association between AF and SCD. We hypothesized that a history of CHF is a significant confounder of this association.

METHODS

In a prospective case-control analysis from the community (The Oregon-SUDS [Sudden Unexpected Death Study], 2002 to 2012), SCD cases (n = 652) with clinical records available (including electrocardiography and/or echocardiography) were compared with age- and sex-matched control patients with coronary artery disease. The association between AF and SCD was analyzed using multivariable logistic regression and propensity score matching.

RESULTS

Cases (age 67.3 ± 11.7 years, 65% male) were more likely than control patients (age 67.2 ± 11.4 years, 65% male) to have a history of AF (p = 0.0001), myocardial infarction (p = 0.007), CHF (p < 0.0001), stroke (p < 0.0001), and diabetes (p < 0.0001). In multivariate analysis without considering CHF, AF was a significant predictor of SCD (odds ratio [OR]: 1.6; 95% confidence interval [CI]: 1.2 to 2.0; p = 0.002). However, in a model that included CHF, the AF-SCD association was no longer significant (OR: 1.1; 95% CI: 0.8 to 1.5; p = 0.45), whereas CHF was a significant predictor of SCD (OR: 3.1; 95% CI: 2.4 to 4.1; p < 0.0001). Results on the basis of propensity score matching were consistent.

CONCLUSIONS

Our findings suggest that a history of CHF, including both systolic and diastolic symptomatic dysfunction, may partially explain the AF-SCD association.

Comparative effectiveness of antiarrhythmic drugs on cardiovascular hospitalization and mortality in atrial fibrillation

AIM

To assess, through a systematic review, evidence for the effects of antiarrhythmic drugs (AADs) on cardiovascular (CV) hospitalization and mortality.

MATERIALS & METHODS

English language articles were identified using MEDLINE, EMBASE and the Cochrane Clinical Trial Registry and were screened for study applicability and methodological quality.

RESULTS

Out of 3526 identified studies, 38 were selected for analysis (19 evaluated individual AADs, 13 compared rate- versus rhythm-control strategies, and 6 evaluated multiple AADs but did not report outcomes for individual agents). None of the studies examining individual AADs employed the CV hospitalization end point used in ATHENA (the reference trial). There were no head-to-head comparisons of individual AADs on CV hospitalization. Most high-quality studies used multidrug rate- versus rhythm-control strategies.

CONCLUSION

Assessment of the comparative effectiveness of individual AADs on CV hospitalization and mortality end points is not possible with the current evidence.

Atrial fibrillation in myocardial infarction patients: Impact on health care utilization

BACKGROUND

Atrial fibrillation (AF) often complicates myocardial infarction (MI). While AF adversely impacts survival in MI patients, the impact of AF on health care utilization has not been studied.

METHODS

The risk of hospitalizations, emergency department (ED) visits, and outpatient visits associated with prior, new-onset (<30 days post-MI), and late-onset (≥30 days post-MI) AF was assessed among incident MI patients from the Olmsted County, Minnesota, community.

RESULTS

Of 1,502 MI patients, 237 had prior AF, 163 developed new-onset AF, 113 developed late-onset AF, and 989 had no AF. Over a mean follow-up of 3.9 years, 3,661 hospitalizations, 5,559 ED visits, and 80,240 outpatient visits occurred. After adjustment, compared with patients without AF, those with prior and new-onset AF exhibited a 1.6-fold and 1.3-fold increased risk of hospitalization, respectively. In contrast, late-onset AF carried a 2.2-fold increased risk of hospitalization. The hazard ratios were 1.4, 1.2, and 1.8 for ED visits and 1.4, 1.2, and 1.7 for outpatient visits for prior, new-onset, and late-onset AF. Additional adjustment for time-dependent recurrent MI and heart failure attenuated the results slightly for hospitalizations and ED visits; however, patients with late-onset AF still exhibited a >50% increased risk for both utilization measures.

CONCLUSIONS

In MI patients, the risk of hospitalizations, ED visits, and outpatient visits differed by the timing of AF onset, with the greatest risk conferred by late-onset AF. Atrial fibrillation imparts an adverse prognosis after MI, underscoring the importance of its management in MI patients.

Usefulness of heart rate to predict one-year mortality in patients with atrial fibrillation and acute myocardial infarction (from the OMEGA trial)

In the setting of acute myocardial infarction and sinus rhythm, the heart rate (HR) has been demonstrated to correlate closely with mortality. In patients presenting with acute myocardial infarction and atrial fibrillation (AF) on admission, however, the prognostic relevance of the HR has not yet been systematically addressed. A post hoc subgroup analysis of the data from the OMEGA trial was conducted to analyze whether the admission HR determines the 1-year mortality in patients presenting with AF in the setting of acute myocardial infarction. Of 3,851 patients enrolled in the OMEGA study, 211 (6%) presented with AF on admission. This subgroup was dichotomized according to the admission HR (cutoff 95 beats/min). Multiple regression analysis revealed that an admission HR of ≥95 beats/min independently determined the 1-year mortality in patients with AF (odds ratio 4.69, 95% confidence interval 1.47 to 15.01; p = 0.01). In conclusion, this is the first study demonstrating that a high HR (≥95 beats/min) on admission in patients with AF and acute myocardial infarction is associated with an almost fivefold mortality risk.

Atrial fibrillation and mortality in patients with acute myocardial infarction: a systematic overview and meta-analysis

Atrial fibrillation (AF) confers an increased risk of mortality in patients hospitalized for acute myocardial infarction (AMI). However, it is unclear whether new-onset and preexisting AF portend a different risk. We extracted data from studies that evaluated in-hospital mortality in patients with AMI and included information on cardiac rhythm. Overall, the risk of mortality was higher in patients with AF than in those in sinus rhythm (OR 2.00, 95 % CI: 1.93-2.08; P < 0.0001). Compared with patients who remained in sinus rhythm, the risk of death was increased in patients with new AF certain (sinus rhythm on admission, new AF during hospitalization, and history of no evidence of prior AF; OR 3.38, 95 % CI: 2.98-3.83; P < 0.0001), new AF uncertain (sinus rhythm on admission, AF during hospitalization, but no clear information about previous history of AF; OR 1.90, 95 % CI:1.83-1.98; P < 0.0001), and permanent AF (AF before and during hospitalization; OR 2.01, 95 % CI:1.70-2.38;P < 0.0001). In a meta-regression analysis, the risk of death was 87 % higher in patients with new AF certain than in those with permanent AF (P = 0.013) or AF uncertain (P = 0.003), and not dissimilar in patients with new AF uncertain and permanent AF (P = 0.706).

Atrial fibrillation and the risk of sudden cardiac death: the atherosclerosis risk in communities study and cardiovascular health study

BACKGROUND

It is unknown whether atrial fibrillation (AF) is associated with an increased risk of sudden cardiac death (SCD) in the general population. This association was examined in 2 population-based cohorts.

METHODS

In the Atherosclerosis Risk in Communities (ARIC) Study, we analyzed data from 15 439 participants (baseline age, 45-64 years; 55.2% women; and 26.6% black) from baseline (1987-1989) through December 31, 2001. In the Cardiovascular Health Study (CHS), we analyzed data from 5479 participants (baseline age, ≥65 years; 58.2% women; and 15.4% black) from baseline (first cohort, 1989-1990; second cohort, 1992-1993) through December 31, 2006. The main outcome was physician-adjudicated SCD, defined as death from a sudden, pulseless condition presumed to be due to a ventricular tachyarrhythmia. The secondary outcome was non-SCD (NSCD), defined as coronary heart disease death not meeting SCD criteria. We used Cox proportional hazards models to assess the association between AF and SCD/NSCD, adjusting for baseline demographic and cardiovascular risk factors.

RESULTS

In the ARIC Study, 894 AF, 269 SCD, and 233 NSCD events occurred during follow-up (median, 13.1 years). The crude incidence rates of SCD were 2.89 per 1000 person-years (with AF) and 1.30 per 1000 person-years (without AF). The multivariable hazard ratios (HRs) (95% CIs) of AF for SCD and NSCD were 3.26 (2.17-4.91) and 2.43 (1.60-3.71), respectively. In the CHS, 1458 AF, 292 SCD, and 581 NSCD events occurred during follow-up (median, 13.1 years). The crude incidence rates of SCD were 12.00 per 1000 person-years (with AF) and 3.82 per 1000 person-years (without AF). The multivariable HRs (95% CIs) of AF for SCD and NSCD were 2.14 (1.60-2.87) and 3.10 (2.58-3.72), respectively. The meta-analyzed HRs (95% CIs) of AF for SCD and NSCD were 2.47 (1.95-3.13) and 2.98 (2.52-3.53), respectively.

CONCLUSIONS

Incident AF is associated with an increased risk of SCD and NSCD in the general population. Additional research to identify predictors of SCD in patients with AF is warranted.

Statins therapy can reduce the risk of atrial fibrillation in patients with acute coronary syndrome: a meta-analysis

BACKGROUND

It is a controversy whether statins therapy could be beneficial for the occurrence of atrial fibrillation (AF) in acute coronary syndrome (ACS). To clarify this problem, we performed a meta-analysis with the currently published literatures.

METHODS

The electronic databases were searched to obtain relevant trials which met the inclusion criteria through October 2011. Two authors independently read the trials and extracted the related information from the included studies. Either fixed-effects models or random-effects models were assumed to calculate the overall combined risk estimates according to I(2 )statistic. Sensitivity analysis was conducted by omitting one study in each turn, and publication bias was evaluated using Begg's and Egger's test.

RESULTS

Six studies were eligible to inclusion criteria, of the six studies, 161305 patients were included in this meta-analysis, 77920 (48.31%) patients had taken the statins therapy, 83385 (51.69%) patients had taken non-statins therapy. Four studies had investigated the effect of statins therapy on occurrence of new-onset AF in ACS patients, another two had described the association between statins therapy and occurrence of AF in ACS patients with AF in baseline. The occurrence of AF was reduced 35% in statins therapy group compared to that in non-statins group (95% confident interval: 0.55-0.77, P<0.0001), and the effect of statins therapy seemed more beneficial for new-onset AF (RR=0.59, 95%CI: 0.48-0.73, p=0.096) than secondary prevention of AF (RR=0.70, 95%CI: 0.43-1.14, p=0.085). There was no publication bias according to the Begg's and Egger's test (Begg, p=0.71; Egger, p=0.73).

CONCLUSION

Statins therapy could reduce the risk of atrial fibrillation in patients with ACS.

Atrial Fibrillation Complicating Acute Coronary Syndromes

Atrial fibrillation frequently complicates myocardial infarction. Patients with atrial fibrillation complicating acute coronary syndrome have increased morbidity and mortality relative to patients that remain in normal sinus rhythm. No studies have identified a mortality benefit to rhythm control compared with rate control in the setting of acute coronary syndrome. Stroke prevention should be pursued with oral anticoagulation therapy, although the majority of patients with atrial fibrillation associated with acute coronary syndrome receive only antiplatelet therapy. There are several novel oral anticoagulant therapies now available, but these agents have not been well studied in combination with dual antiplatelet therapy. Therefore, warfarin as part of triple therapy is the most conservative approach until additional data becomes available.

Atrial fibrillation and death after myocardial infarction: a community study

BACKGROUND

Atrial fibrillation (AF) often coexists with myocardial infarction (MI), yet its prognostic influence is disputed. Prior reports studied the relationship of AF during early hospitalization for acute MI to the risk of death and could not address the timing of AF in relation to the MI (ie, before, during, after). Furthermore, as data come mostly from clinical trials, their applicability to the community is uncertain. The aims of our study were to assess the occurrence of AF among MI patients, determine whether it has changed over time, and quantify its impact and the impact of its timing on mortality after MI.

METHODS AND RESULTS

This was a community-based cohort of 3220 patients hospitalized with incident (first-ever) MI from 1983 to 2007 in Olmsted County, MN. Atrial fibrillation was identified by diagnostic codes and ECG. Outcomes were all-cause and cardiovascular death. Atrial fibrillation before MI was identified in 304 patients, and 729 developed AF after MI (218 [30%] within 2 days, 119 [16%] between 3 and 30 days, and 392 [54%] >30 days post-MI). The cumulative incidence of AF after MI at 5 years was 19% and did not change over the calendar year of MI (the incidence of AF was the same regardless of when the MI occurred). During a mean follow-up of 6.6 years, 1638 deaths occurred. AF was associated with an increased risk of death (hazard ratio [95% confidence interval] 3.77 [3.37 to 4.21]), independently of clinical characteristics at the time of MI and heart failure. This risk differed markedly according to the timing of AF, and was the greatest for AF occurring >30 days post MI (hazard ratio [95% confidence interval] 1.63 [1.37 to 1.93] for AF within 2 days, 1.81 [0.45 to 2.27] for AF between 3 and 30 days, and 2.58 [2.21 to 3.00] for AF >30 days post MI).

CONCLUSIONS

In the community, AF is frequent in the setting of MI. Atrial fibrillation carries an excess risk of death, which is the highest for AF developing >30 days after MI.

Mortality associated with atrial fibrillation in patients with myocardial infarction: a systematic review and meta-analysis

BACKGROUND

Atrial fibrillation (AF) is a common finding in patients with myocardial infarction (MI). Atrial fibrillation is not generally perceived by clinicians as a critical event during the acute phase of MI; however, its prognostic influence in MI remains controversial. Furthermore, contradictory data exist concerning the risk of death according to AF timing. This article, a systematic review and first meta-analysis, aims to quantify the mortality risk associated with AF in MI patients and its timing.

METHODS AND RESULTS

A comprehensive search of several electronic databases (1970 to 2010; adults, any language) identified MI studies that evaluated mortality related to AF. Evidence was reviewed by 2 blinded reviewers with a formal assessment of the methodological quality of the studies. Adjusted odds ratios were pooled across studies using the random-effects model. The I(2) statistic was used to assess heterogeneity. In the 43 included studies (278 854 subjects), the mortality odds ratio associated with AF was 1.46 (95% confidence interval, 1.35 to 1.58; I(2)=76%; 23 studies). This worse prognosis persisted regardless of the timing of AF; the odds ratio of mortality for new AF with no prior history of AF was 1.37 (95% confidence interval, 1.26 to 1.49), I(2)=28%, 9 studies), and for prior AF was 1.28 (95% confidence interval, 1.16 to 1.40; I(2)=24%; 4 studies). The sensitivity analysis of new AF studies adjusting for confounding factors did not show a decrease in risk of death.

CONCLUSIONS

Atrial fibrillation is associated with increased risk of mortality in MI patients. New AF with no history of AF before MI remained associated with an increased risk of mortality even after adjustment for several important AF risk factors. These subsequent increases in mortality suggest that AF can no longer be considered a nonsevere event during MI.

New-onset versus chronic atrial fibrillation in acute myocardial infarction: differences in short- and long-term follow-up

AIMS

Atrial fibrillation (AF) occurs commonly in patients with acute myocardial infarction (AMI) and has been established as a marker of adverse prognosis. There are only few clinical trials that investigate differences between new-onset and chronic AF in AMI. We hypothesize that chronic AF is associated with an increased rate of adverse short- and long-term outcomes.

METHODS AND RESULTS

In a single center study, over a period of 28 months, 375 consecutive patients with AMI were included [337 patients without AF (89.9%) and 38 with AF (10.1%)]. As much as 16 patients had new-onset AF (42.1%) and 22 had chronic AF (57.9%). Patients with severe coronary artery disease develop AF more often in AMI, and the existence of AF was associated with a poor prognosis. Compared to patients with new-onset AF, chronic AF was more frequently associated with advanced age (75 vs. 70 years, p not significant), reduced left ventricular ejection fraction (44.8 vs. 54.0%, p < 0.05) and NSTEMI (63.6 vs. 36.4%, p < 0.05). Only chronic AF resulted in increased in-hospital death (18.2 vs. 0.0%; p < 0.005) at the 2-year follow-up, 14 patients with AF died (63.6%), predominantly due to cardiovascular reasons.

CONCLUSION

Our results indicate that patients with chronic AF had a higher incidence of in-hospital death than those with new-onset AF or without. Chronic AF includes a group of older and sicker patients than their counterparts with new-onset AF. Understanding these findings may ultimately lead to better care of patients with this arrhythmia to prevent the development of the underlying atrial substrate in chronic AF patients and to improve their otherwise worse prognosis.