Prognostic significance of atrial fibrillation is a function of left ventricular ejection fraction

Echocardiographic Findings in Jordanian Atrial Fibrillation Patients: Analysis from Jo-Fib Study

Background and Objectives: Atrial fibrillation (AF) carries a huge socioeconomic burden as it is the most encountered cardiac arrhythmia with a significant morbidity. Echocardiographic (Echo) imaging is of monumental value in providing insight into assessing the cardiac function and anatomy, etiology, and risk stratification of AF patients, which will ultimately lead to the best management plan. Materials and Methods: A total of 2160 adult patients diagnosed with AF in 18 hospitals and 30 out-patient cardiology clinics in Jordan and 1 hospital in the Palestinian Territories were enrolled in this study from May 2019 to January 2021. Ultimately, 1776 patients were included in the analysis after going through the exclusion criteria. Results: The majority of our participants were found to have normal EF at the time of enrollment, with only 31.6% exhibiting a decreased EF. Only 40% of overall patients had Echo evidence of left ventricular hypertrophy (LVH). These patients were older (70.27 ± 10.1 vs. 66.0 ± 14.3, p < 0.001), more obese (45.2% vs. 37.3%, p-value < 0.001), and had a more frequent occurrence of HTN (89.0% vs. 65.6%, p < 0.001) and DM (49.2% vs. 40.1%, p < 0.001) when compared to patients without LVH. A proportion of 84.2% of female patients had abnormal left atrial (LA) size (>3.8 cm), in contrast to only 53.4% of males (LA > 4.2 cm). Pulmonary hypertension (PH) was only observed in 27.9% of our patients, and when comparing patients with PH vs. patients without PH, decreased EF (<50%) (36.9% vs. 20.6%, p = 0.001), a higher prevalence of OSA (6.7% vs. 3.8%, p = 0.009), female predominance (60.3% vs. 39.7%, p < 0.001), and older age (70.2 ± 10.7 vs. 66.7 ± 13.6, p < 0.001) were observed in patients with PH. Conclusion: This study provides the first reported insights on the atrial fibrillation-related echocardiographic findings in a Middle Eastern population. Notably, our study demonstrates that the majority of the studied population have no evidence of LVH and have preserved EF on baseline. However, LA enlargement was extremely frequent among females but not in males, warranting further evaluation to determine the factors contributing to such a difference.

Relative Contribution of Atrial Fibrillation to Outcomes of Patients With Cardiomyopathy Based on Severity of Left Ventricular Dysfunction

In patients with left ventricular (LV) dysfunction, the risk of death or heart failure hospitalizations (HFHs) increases with worsening ejection fraction (EF). Whether the relative contribution of atrial fibrillation (AF) to outcomes is more pronounced in patients with worse EF is not confirmed. The present study aimed to investigate the relative influence of AF on the outcome of cardiomyopathy patients by severity of LV dysfunction. In this observational study, data from 18,003 patients with EF ≤50% seen at a large academic institution between 2011 and 2017 were analyzed. Patients were stratified by EF quartiles (EF<25%, 25%≤EF<35%, 35%≤EF<40%, and EF≥40%, for quartiles 1, 2, 3, and 4, respectively). and followed to the end point of death or HFH. Outcomes of AF versus non-AF patients were compared within each EF quartile. During a median follow-up of 3.35 years, 8,037 patients (45%) died and 7,271 (40%) had at least 1 HFH. Rates of HFH and all-cause mortality increased as EF decreased. The hazard ratios (HRs) of death or HFH for AF versus non-AF patients increased steadily with increasing EF (HR of 1.22, 1.27, 1.45, 1.50 for quartiles 1, 2, 3, and 4, respectively, p = 0.045) driven primarily by the risk of HFH (HR of 1.26, 1.45, 1.59, 1.69 for quartiles 1, 2, 3, and 4, respectively, p = 0.045). In conclusion, in patients with LV dysfunction, the detrimental influence of AF on the risk of HFH is more pronounced in those with more preserved EF. Mitigation strategies for AF with the goal of decreasing HFH may be more impactful in patients with more preserved LV function.

Breaking the Cycle of Heart Failure With Preserved Ejection Fraction and Atrial Fibrillation

Heart failure with preserved ejection fraction (HFpEF) and AF are two common cardiovascular conditions that are inextricably linked to each other's development and progression, often in multimorbid patients. Current management is often directed to specific components of each disease without considering their joint impact on diagnosis, treatment and prognosis. The result for patients is suboptimal on all three levels, restricting clinicians from preventing major adverse events, including death, which occurs in 20% of patients at 2 years and in 45% at 4 years. New trial evidence and reanalysis of prior trials are providing a glimmer of hope that adverse outcomes can be reduced in those with concurrent HFpEF and AF. This will require a restructuring of care to integrate heart failure and AF teams, alongside those that manage comorbidities. Parallel commencement and non-sequential uptitration of therapeutics across different domains will be vital to ensure that all patients benefit at a personal level, based on their own needs and priorities.

Effect of systolic dysfunction and elevated left ventricular end diastolic pressure on 3-year clinical outcomes in patients with atrial fibrillation

OBJECTIVES

Systolic and diastolic dysfunctions are related to adverse clinical outcomes in patients with sinus rhythm. The aim of this study was to clarify the prognostic significance of systolic and diastolic dysfunctions in patients with persistent atrial fibrillation (AF).

METHODS

We evaluated the data of 114 consecutive patients with persistent AF who underwent measurement of LVEDP at our hospital between March 1, 2011 and December 31, 2014. The patients were divided into two groups according to the left ventricular ejection fraction (LVEF): LVEF < 50 (reduced ejection fraction, REF group) and LVEF ≥50 (preserved EF, PEF group). The PEF group was further divided into two subgroups according to the left ventricular end-diastolic filling pressure (LVEDP): LVEDP > 15 mm Hg and LVEDP ≤ 15 mm Hg subgroups. The 3-year clinical outcomes were compared between the PEF and REF groups and the LVEDP ≥15 mm Hg and LVEDP < 15 mm Hg groups.

RESULTS

During the 3-year follow-up period, the rate of heart failure (HF) hospitalization and incidence of AF with rapid ventricular rhythm (RVR) were higher in the REF group than in the PEF group. Multivariate analysis revealed that REF was the only significant predictor of HF hospitalization (hazard ratio, 4.71; 95% confidence interval, 1.48-15.02; p = 0.009).

CONCLUSIONS

Our mid-term follow-up data demonstrated that systolic dysfunction was an important predictor of HF hospitalization in patients with AF. However, elevated LVEDP may not be associated with adverse mid-term clinical outcomes in patients without systolic dysfunction.

The Impact of Hypertension and Atrial Fibrillation on Cognitive Decline and Subclinical Atherosclerosis

BACKGROUND

Assessment of cognitive impairment and the presence of subclinical atherosclerosis are very important especially in patients with cardiovascular risk factors.

METHODS

We included 155 hypertensive patients (84 with AF versus 71 without AF) to identify the premature cognitive impairment, the earliest signs of subclinical atherosclerosis and onset of myocardial dysfunction and to evaluate the type of anticoagulation used, the importance of CHA₂DS₂-VASc score (3), age (65 years) in hypertensive patients with AF.

RESULTS

Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment Scale (MoCA), Left Ventricular Ejection Fraction (LVEF) were significantly decreased, and Activities of Daily Living Score (ADL), Geriatric Depression Scale(GDS-15), and intima-media thickness (IMT) were significantly increased in hypertensive patients with AF vs. without AF (p < 0.05). MMSE was significantly decreased, ADL and IMT were significant increased in patients with AF and CHA₂DS₂-VASc>3 and non-vitamin K antagonists oral anticoagulants therapy (NOACs)(p < 0.05). Patients with age >65 with AF had higher rates of cognitive impairment (MMSE significant decrease) and a larger IMT (significant increase) versus patients with AF and age <65 (p < 0.05).

CONCLUSIONS

Cognitive impairment is encountered in hypertensive patients having AF. Our conclusions suggest a direct link between cognitive impairment, depression, hypertension, AF, age, CHA₂DS₂-VASc score, type of anticoagulants used, LVEF, cognitive parameters, and IMT. We acknowledge the importance of identifying and preventing cognitive changes.

The Evolving Epidemiology of Elderly with Degenerative Valvular Heart Disease: The Guangzhou (China) Heart Study

Aim

The present study was aimed at investigating the prevalence, incidence, progression, and prognosis of degenerative valvular heart disease (DVHD) in permanent residents aged ≥65 years from Guangzhou, China.

Methods

This was a prospective study based on community population. Over a 3-year span, we conducted repeated questionnaires, blood tests, and echocardiographic and electrocardiogram examinations (2018) of a random sample of initially 3538 subjects.

Results

The prevalence of DVHD increased with age, average values being 30.6%, 49.2%, and 62.9% in 65-74, 75-84, and ≥85 years of age, respectively. The incidence rate was 1.7%/year. Aortic stenosis was the result of DVHD, and the mean transvalvular pressure gradient increased by 5.6 mmHg/year. The increase of mild aortic stenosis was lower than that of more severe disease, showing a nonlinear development of gradient, but with great individual variations. Mortality was significantly increased in the DVHD group (HR = 2.49). Risk factors for higher mortality included age (χ² = 1.9, P < 0.05), renal insufficiency (χ² = 12.5, P < 0.01), atrial fibrillation (χ² = 12.2, P < 0.01), mitral regurgitation (χ² = 1.8, P < 0.05), and tricuspid regurgitation (χ² = 6.7, P < 0.05) in a DVHD population.

Conclusions

DVHD was highly prevalent among residents in southern China. With the progression of the disease, the mean transvalvular pressure gradient accelerated. DVHD was an independent predictor of death, and the mortality was higher in those with older age, renal insufficiency, atrial fibrillation, mitral regurgitation, and tricuspid regurgitation.

Atrial Fibrillation and Heart Failure: Epidemiology, Pathophysiology, Prognosis, and Management

Atrial fibrillation (AF) and heart failure (HF) have similar risk factors, frequently coexist, and potentiate each other in a vicious cycle. Evidence suggests the presence of AF in both HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF) increases the risk of all-cause mortality and stroke, particularly when AF is incident. Catheter ablation may be an effective strategy in controlling symptoms and improving quality of life in AF-HFrEF. Strong data guiding management of AF-HFpEF are lacking largely due to its challenging diagnosis. Improving outcomes associated with these coexistent conditions requires further careful investigation.

Atrial fibrillation in patients with heart failure with preserved ejection fraction

PURPOSE OF REVIEW

To review the shared pathology of atrial fibrillation and heart failure with preserved ejection fraction (HFpEF) and the prognostic, diagnostic, and treatment challenges incurred by the co-occurrence of these increasingly prevalent diseases.

RECENT FINDINGS

Multiple risk factors and mechanisms have been proposed as potentially linking atrial fibrillation and HFpEF, with systemic inflammation more recently being invoked. Nonvitamin K oral anticoagulants, left atrial appendage occlusion devices, and catheter ablation have emerged as alternative treatment options. Other novel pharmacological agents, such as neprilysin inhibitors, need to be studied further in this patient population.

SUMMARY

Atrial fibrillation and HFpEF commonly co-occur because of their shared risk factors and pathophysiology and incur increased morbidity and mortality relative to either condition alone. Although the presence of both diseases can often make each diagnosis difficult, it is important to do so early in the disease course as there are now a variety of treatment options aimed at improving symptoms and quality of life, slowing disease progression, and improving prognosis. However, more research needs to be performed on the role of catheter ablation in this population. Novel pharmacologic and procedural treatment options appear promising and may further improve the treatment options available to this growing population.

Aortic stiffness-Is kynurenic acid a novel marker? Cross-sectional study in patients with persistent atrial fibrillation

Objective

Although a number of modifiable and non-modifiable causes were implicated in arterial stiffness, its pathogenesis remains elusive, and very little is known about aortic elasticity in supraventricular arrhythmias. The potential role of disturbed kynurenine metabolism in the pathogenesis of cardiovascular disease has been recently suggested. Thus, we studied the correlations of aortic stiffness and echocardiographic parameters with biochemical markers and serum level of kynurenic acid (KYNA), an endothelial derivative of tryptophan, formed along the kynurenine pathway, among patients with atrial fibrillation (AF).

Methods

Study cohort comprised 100 patients with persistent AF (43 females/57 males). Arterial stiffness index (ASI), structural and functional indices of left atrium (LA) and left ventricle (LV) were evaluated electrocardiographically. Biochemical analyses included the measurements of serum KYNA (HPLC) and of the selected markers of lipids and glucose metabolism, thyroid status, kidney function, inflammation and coagulation.

Results

KYNA (β = 0.389, P = 0.029), homocysteine (β = 0.256, P = 0.40), total cholesterol (β = 0.814; P = 0.044), LDL (β = 0.663; P = 0.44), TSH (β = 0.262, P = 0.02), fT₃ (β = -0.333, P = 0.009), fT₄ (β = -0.275, P = 0.043) and creatinine (β = 0.374, P = 0.043) were independently correlated with ASI. ASI was also independently associated with LV end-systolic diameter (LVEDd; β = 1.751, P = 0.045), midwall fractional shortening (mFS; β = -1.266, P = 0.007), ratio mFS/end-systolic stress (mFS/ESS; β = -0.235, P = 0.026), LV shortening fraction (FS; β = -0.254, P = 0.017), and LA volume index (LAVI; β = 0.944, P = 0.022).

Conclusions

In patients with AF, aortic stiffness correlated positively with KYNA, biochemical risk factors of atherosclerosis and with the indices of diastolic dysfunction of LV and LA. Revealed relationship between ASI and KYNA is an original observation, suggesting a potential role of disturbed kynurenine metabolism in the pathogenesis of arterial stiffening. KYNA, synthesis of which is influenced by homocysteine, emerges as a novel, non-classical factor associated with ASI in patients with AF.

Model-Based Quantification of Left Ventricular Diastolic Function in Critically Ill Patients with Atrial Fibrillation from Routine Data: A Feasibility Study

Introduction

Left ventricular diastolic dysfunction (LVDD) and atrial fibrillation (AF) are connected by pathophysiology and prevalence. LVDD remains underdiagnosed in critically ill patients despite potentially significant therapeutic implications since direct measurement cannot be performed in routine care at the bedside, and echocardiographic assessment of LVDD in AF is impaired. We propose a novel approach that allows us to infer the diastolic stiffness, β, a key quantitative parameter of diastolic function, from standard monitoring data by solving the nonlinear, ill-posed inverse problem of parameter estimation for a previously described mechanistic, physiological model of diastolic filling. The beat-to-beat variability in AF offers an advantageous setting for this.

Methods

By employing a global optimization algorithm, β is inferred from a simple six parameter and an expanded seven parameter model of left ventricular filling. Optimization of all parameters was limited to the interval ]0, 400[ and initialized randomly on large intervals encompassing the support of the likelihood function. Routine ECG and arterial pressure recordings of 17 AF and 3 sinus rhythm (SR) patients from the PhysioNet MGH/MF Database were used as inputs.

Results

Estimation was successful in 15 of 17 AF patients, while in the 3 SR patients, no reliable estimation was possible. For both models, the inferred β (0.065 ± 0.044 ml⁻¹ vs. 0.038 ± 0.033 ml⁻¹ (p=0.02) simple vs. expanded) was compatible with the previously described (patho) physiological range. Aortic compliance, α, inferred from the expanded model (1.46 ± 1.50 ml/mmHg) also compared well with literature values.

Conclusion

The proposed approach successfully inferred β within the physiological range. This is the first report of an approach quantifying LVDF from routine monitoring data in critically ill AF patients. Provided future successful external validation, this approach may offer a tool for minimally invasive online monitoring of this crucial parameter.

Linking Atrial Fibrillation with Alzheimer's Disease: Epidemiological, Pathological, and Mechanistic Evidence

Many studies have shown a relationship between atrial fibrillation (AF) and vascular dementia. AF is a major risk factor for stroke, and stroke is the greatest risk factor for vascular dementia. However, the relationship between Alzheimer's disease (AD), the leading cause of dementia, and AF remains unclear. At least four epidemiological studies have reported AF significantly raises the risk of AD 1.5- to 2.5-fold. Chronic cerebral hypoperfusion, resulting from persistent AF, could explain the link as hypoperfusion may mechanistically exacerbate amyloid-β (Aβ) neuropathology, such as senile plaques and amyloid angiopathy, by upregulating Aβ-producing enzymes and lowering Aβ clearance efficiency. In addition, hypoperfusion may exacerbate tau pathology directly through upregulation of tau-phosphorylating enzymes and indirectly via the amyloid cascade. However, most neuropathological studies do not support the direct link between AD pathology and AF but rather suggests vascular neuropathology is related to, or coexistent with, AF and lowers the threshold for clinically-evident AD. Vascular neuropathology may thus mediate the link between AD and AF. From a treatment perspective, an observational study has shown that catheter ablation is associated with less incidence of AD in AF patients, suggesting rhythm-control suppresses hypoperfusion-induced AD neuropathology. In addition, rate-control may lower the rate of cognitive decline in cognitively impaired elderly subjects with AF. Further studies are warranted to clarify the mechanisms underlying the linkage between AF and AD. However, anticoagulation and rhythm-/rate-control against AF may hold promise even for AD patients.

Retrospective Evaluation of the Effect of Heart Rate on Survival in Dogs with Atrial Fibrillation

Background

Atrial fibrillation (AF) usually is associated with a rapid ventricular rate. The optimal heart rate (HR) during AF is unknown.

Hypothesis/Objectives

Heart rate affects survival in dogs with chronic AF.

Animals

Forty‐six dogs with AF and 24‐hour ambulatory recordings were evaluated.

Methods

Retrospective study. Holter‐derived HR variables were analyzed as follows: mean HR (meanHR, 24‐hour average), minimum HR (minHR, 1‐minute average), maximum HR (maxHR, 1‐minute average). Survival times were recorded from the time of presumed adequate rate control. The primary endpoint was all‐cause mortality. Cox proportional hazards analysis identified variables independently associated with survival; Kaplan‐Meier survival analysis estimated the median survival time of dogs with meanHR <125 bpm versus ≥125 bpm.

Results

All 46 dogs had structural heart disease; 31 of 46 had congestive heart failure (CHF), 44 of 46 received antiarrhythmic drugs. Of 15 dogs with cardiac death, 14 had CHF. Median time to all‐cause death was 524 days (Interquartile range (IQR), 76–1,037 days). MeanHR was 125 bpm (range, 62–203 bpm), minHR was 82 bpm (range, 37–163 bpm), maxHR was 217 bpm (range, 126–307 bpm). These were significantly correlated with all‐cause and cardiac‐related mortality. For every 10 bpm increase in meanHR, the risk of all‐cause mortality increased by 35% (hazard ratio, 1.35; 95% CI, 1.17–1.55; P < 0.001). Median survival time of dogs with meanHR<125 bpm (n = 23) was significantly longer (1,037 days; range, 524‐open) than meanHR ≥125 bpm (n = 23; 105 days; range, 67–267 days; P = 0.0012). Mean HR was independently associated with all‐cause and cardiovascular mortality (P < 0.003).

Conclusions and Clinical Importance

Holter‐derived meanHR affects survival in dogs with AF. Dogs with meanHR <125 bpm lived longer than those with meanHR ≥ 125 bpm.

Atrial Fibrillation in Heart Failure: a Therapeutic Challenge of Our Times

Atrial fibrillation (AF) and heart failure (HF) are growing cardiovascular disease epidemics worldwide. There has been an exponential increase in the prevalence of AF and HF correlating with an increased burden of cardiac risk factors and improved survival rates in patients with structural heart disease. AF is associated with adverse prognostic outcomes in HF and is most evident in mild-to-moderate left ventricular (LV) dysfunction where the loss of "atrial kick" translates into poorer quality of life and increased mortality. In the absence of underlying structural heart disease, arrhythmia can independently contribute to the development of cardiomyopathy. Together, these 2 conditions carry a high risk of thromboembolism due to stasis, inflammation and cellular dysfunction. Stroke prevention with oral anticoagulation (OAC) remains a mainstay of treatment. Pharmacologic rate and rhythm control remain limited by variable efficacy, intolerance and adverse reactions. Catheter ablation for AF has resulted in a paradigm shift with evidence indicating superiority over medical therapy. While its therapeutic success is high for paroxysmal AF, it remains suboptimal in persistent AF. A better mechanistic understanding of AF as well as innovations in ablation technology may improve patient outcomes in the future. Refractory cases may benefit from atrioventricular junction ablation and biventricular pacing. The value of risk factor modification, especially with regard to obesity, sleep apnea, hypertension and diabetes, cannot be emphasized enough. Close interdisciplinary collaboration between HF specialists and electrophysiologists is an essential component of good long-term outcomes in this challenging population.

Mortality and Atrial Fibrillation in the FIACA Study: Evidence of a Differential Effect According to Admission Diagnosis

INTRODUCTION AND OBJECTIVES

Atrial fibrillation (AF) is an independent risk factor for mortality in several diseases. However, data published in acute decompensated heart failure (DHF) are contradictory. Our objective was to investigate the impact of AF on mortality in patients admitted to hospital for DHF compared with those admitted for other reasons.

METHODS

This retrospective cohort study included all patients admitted to hospital within a 10-year period due to DHF, acute myocardial infarction (AMI), or ischemic stroke (IS), with a median follow-up of 6.2 years.

RESULTS

We included 6613 patients (74 ± 11 years; 54.6% male); 2177 with AMI, 2208 with DHF, and 2228 with IS. Crude postdischarge mortality was higher in patients with AF hospitalized for AMI (incident rate ratio, 2.48; P < .001) and IS (incident rate ratio, 1.84; P < .001) than in those without AF. No differences were found in patients with DHF (incident rate ratio, 0.90; P = .12). In adjusted models, AF was not an independent predictor of in-hospital mortality by clinical diagnosis. However, AF emerged as an independent predictor of postdischarge mortality in patients with AMI (HR, 1.494; P = .001) and IS (HR, 1.426; P < .001), but not in patients admitted for DHF (HR, 0.964; P = .603).

CONCLUSIONS

AF was as an independent risk factor for postdischarge mortality in patients admitted to hospital for AMI and IS but not in those admitted for DHF.

The prognostic significance of atrial fibrillation in heart failure with preserved ejection function: insights from KaRen, a prospective and multicenter study

The prognostic value of atrial fibrillation (AF) in heart failure with preserved ejection fraction (HFPEF) remains controversial. We sought to study the prognostic value of AF in a prospective cohort and to characterize the HFPEF patients with AF. KaRen was a prospective, multicenter, international, observational study intended to characterize HFPEF; 538 patients presenting with an acute decompensated cardiac failure and a left ventricular EF > 45% were included. EKG and echocardiogram performed 4-8 week following the index hospitalization were analyzed in core centers. Clinical and echocardiographic characteristics of patients in sinus rhythm vs. with documented AF at enrolment (decompensated HF), upon their 4-8-week visit (in presumed stable clinical condition) and according to patients' cardiac history, were compared. The primary study endpoint was death from any cause or first hospitalization for decompensated heart failure (HF). A total of 413 patients (32% in AF) were analyzed, with a mean follow-up period of 28 months. The patients were primarily elderly individuals (mean age: 76.2 years), with a slight female predominance and a high prevalence of non-cardiovascular comorbidities. The baseline echocardiographic characteristics and the natriuretic peptide levels were indicative of a more severe heart condition among the patients with AF. However, the patients with AF exhibited a similar survival-free interval compared with the patients in sinus rhythm. In this elderly HFPEF population with a high prevalence of non-cardiovascular comorbidities, the presence of AF was not associated with a worse prognosis despite impaired clinical and echocardiographic features.ClinicalTrials.gov: NCT00774709.

Atrial fibrillation and heart failure: Factors influencing the choice of oral anticoagulant

Atrial fibrillation (AF) and heart failure (HF) frequently coexist. AF is identified in approximately one third of patients with HF and is linked to increased morbidity and mortality than from either condition alone. AF is relatively more common in HF with preserved ejection fraction (HFpEF) than with reduced ejection fraction (HFrEF). Nevertheless, the risk of stroke and systemic embolism (SSE) is significantly increased with both HF types and the absolute risk is heavily influenced by the presence and severity of associated additional stroke risk factors. The European Society of Cardiology has very recently introduced a third HF subtype entitled HF with mid-range ejection fraction (HFmrEF). At present oral anticoagulation is recommended for all patients with AF and HF, independent of HF type. In addition to warfarin there are currently four non-vitamin K oral anticoagulants (NOACs, previously called novel oral anticoagulants) that have been approved for the prevention of SSE. They consist of one direct thrombin inhibitor, dabigatran and three factor Xa inhibitors: rivaroxaban, apixaban and, most recently, edoxaban. In this review article we present an overview of the evidence to support the use of NOACs for the prevention of SSE in patients with AF and HF and review the influence of HF subtype and co-morbidities on the potential choice of oral anticoagulant.

Survival in Patients with Degenerative Mitral Stenosis: Results from a Large Retrospective Cohort Study

BACKGROUND

Severe mitral annular calcification causing degenerative mitral stenosis (DMS) is increasingly encountered in patients undergoing mitral and aortic valve interventions. However, its clinical profile and natural history and the factors affecting survival remain poorly characterized. The goal of this study was to characterize the factors affecting survival in patients with DMS.

METHODS

An institutional echocardiographic database was searched for patients with DMS, defined as severe mitral annular calcification without commissural fusion and a mean transmitral diastolic gradient of ≥2 mm Hg. This resulted in a cohort of 1,004 patients. Survival was analyzed as a function of clinical, pharmacologic, and echocardiographic variables.

RESULTS

The patient characteristics were as follows: mean age, 73 ± 14 years; 73% women; coronary artery disease in 49%; and diabetes mellitus in 50%. The 1- and 5-year survival rates were 78% and 47%, respectively, and were slightly worse with higher DMS grades (P = .02). Risk factors for higher mortality included greater age (P < .0001), atrial fibrillation (P = .0009), renal insufficiency (P = .004), mitral regurgitation (P < .0001), tricuspid regurgitation (P < .0001), elevated right atrial pressure (P < .0001), concomitant aortic stenosis (P = .02), and low serum albumin level (P < .0001). Adjusted for propensity scores, use of renin-angiotensin system blockers (P = .02) or statins (P = .04) was associated with better survival, and use of digoxin was associated with higher mortality (P = .007).

CONCLUSIONS

Prognosis in patients with DMS is poor, being worse in the aged and those with renal insufficiency, atrial fibrillation, and other concomitant valvular lesions. Renin-angiotensin system blockers and statins may confer a survival benefit, and digoxin use may be associated with higher mortality in these patients.

Atrial fibrillation in heart failure: The sword of Damocles revisited

Heart failure (HF) and atrial fibrillation (AF) frequently coexist and have emerged as major cardiovascular epidemics. There is growing evidence that AF is an independent prognostic marker in HF and affects patients with both reduced as well as preserved LV systolic function. There has been a general move in clinical practice from a rhythm control to a rate control strategy in HF patients with AF, although recent data suggests that rhythm control strategies may provide better outcomes in selected subgroups of HF patients. Furthermore, various therapeutic modalities including pace and ablate strategies with cardiac resynchronisation or radiofrequency ablation have become increasingly adopted, although their role in the management of AF in patients with HF remains uncertain. This article presents an overview of the multidimensional impact of AF in patients with HF. Relevant literature is highlighted and the effect of various therapeutic modalities on prognosis is discussed. Finally, while novel anticoagulants usher in a new era in thromboprophylaxis, research continues in a variety of new pathways including selective atrial anti-arrhythmic agents and genomic polymorphisms in AF with HF.

High-risk electrocardiographic parameters are ubiquitous in patients with ischemic cardiomyopathy

BACKGROUND

The electrocardiogram (ECG) can be used to predict cardiovascular risk; however, like all risk factors with imperfect specificity, studies in low risk populations have been plagued by poor predictive accuracy. Although predictive accuracy might be improved among cohorts with a higher likelihood of cardiovascular events, this would also affect the prevalence of abnormal parameters and their exclusions.

METHOD

To determine the magnitude of these changes in a cohort with ischemic cardiomyopathy we analyzed 15 previously validated high-risk parameters from the resting and ambulatory ECG in subjects enrolled in the Prediction of Arrhythmic Events with Positron Emission Tomography (PAREPET) study (n = 198).

RESULTS

Using the published exclusion criteria from the validation studies (i.e., atrial fibrillation, persistent pacing, prolonged QRS), only 4 high-risk ECG parameters (27%) could be evaluated in all subjects and only 42% of subjects could have all 15 ECG parameters assessed. Nevertheless, almost every subject (97%) had at least one abnormal parameter. On average, there were 3.4 ± 1.8 (range, 0-8) high-risk ECG parameters per subject among the 11.7 ± 4.5 (range, 4-15) parameters that could be assessed.

CONCLUSIONS

Thus, 34% of all assessable parameters were abnormal. In conclusion, a significant proportion of ECG parameters cannot be assessed in patients with ischemic cardiomyopathy, but high-risk results are ubiquitous. The influence of these issues will be clarified when the results of the PAREPET study are available to actually determine the predictive value of these parameters on cause-specific mortality in a high-risk cohort.

A review of the epidemiological profile of patients with atrial fibrillation and heart failure

Heart failure (HF) and atrial fibrillation (AF) are cardiovascular diseases that have a continuously increasing prevelance and both often coexist. The presence of AF in HF patients has been reported as being between 10 and 50% depending on the different study settings. AF patients have a different clinical profile: they are older, with more severe HF and comorbidities than those without AF. Despite this poor clinical profile, observational studies report a lower use of the recommended treatments such as angiotensin-converting enzyme inhibitors and β-blockers. Clinical trials using antiarrhythmic drugs for rhythm control have failed to demonstrate the clinical advantage of a rhythm control approach over one for rate control. The prognostic role of AF in HF remains controversial, while the impact of new AF has been shown to be associated with an adverse outcome.

Heart failure, diastolic dysfunction and atrial fibrillation; mechanistic insight of a complex inter-relationship

Atrial fibrillation (AF) and heart failure (HF) commonly coexist, and their co-presence is associated with adverse outcomes relating to thromboembolic events, HF progression, hospitalisation and death. Diastolic dysfunction (DD) is also frequently present in patients with HF and is an independent predictor of hospitalisation and mortality. The presence of DD is a strong predictor of incident AF in patients with HF. In this review, we provide mechanistic insight into pathophysiological processes that frequently promote the occurrence of AF, HF and DD and outline the yin-yang relationship between AF, DD and HF. More recently, invasive studies have also shown that asymptomatic paroxysmal atrial fibrillation (PAF) is a common phenomenon in HF patients. We examine complex inter-relationships between PAF, HF and DD and speculate upon the possible clinical influence of undiagnosed PAF in HF patients.

Rate vs rhythm control in patients with atrial fibrillation and heart failure: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Atrial fibrillation (AF) is a common arrhythmia that can promote or worsen heart failure (HF). Our purpose was to compare the effects of rate and rhythm control in patients with atrial fibrillation and heart failure.

METHODS

We developed a systematic search in August 2010 through CENTRAL and MEDLINE databases to identify randomised controlled trials (RCTs) comparing rate control with rhythm control in patients with both AF and HF. We analysed mortality, hospitalisations, stroke/thromboembolic events, quality of life, and drugs adverse events. Relative risks (RR) and 95% confidence intervals (95% CI) were calculated for mortality and hospitalisations. The remaining outcomes were analysed qualitatively.

RESULTS

Four RCTs with a total of 2486 patients with atrial fibrillation and heart failure were identified. Mortality and stroke/thromboembolic events were not significantly different in rate and rhythm control arms [RR 1.03; 95% CI: 0.90-1.17] and [RR 1.09; 95% CI: 0.61-1.96], respectively. Hospitalisations were less frequent with rate control than with rhythm control [RR 0.92; 95% CI: 0.86-0.98; p=0.008], in 3 studies involving 2425 patients. Number needed to treat to prevent one hospitalisation was 19 patients.

CONCLUSIONS

In patients with AF and HF, rate control compared with rhythm control showed inferior risk of hospitalisation.

No impact of atrial fibrillation on mortality risk in optimally treated heart failure patients

BACKGROUND

Several studies have shown that atrial fibrillation (AF) is associated with increased risk of death in heart failure (HF) patients. However, it is not clear whether this increased risk is independent of other risk factors.

HYPOTHESIS

We hypothesized that AF would be an independent risk factor for death in a large cohort of HF patients.

METHODS

Patients referred to Norwegian HF outpatient clinics were enrolled between October 2000 and February 2008. Patients with heart rhythm other than AF or sinus rhythm were excluded. Mortality data were obtained from the National Statistics Bureau, Statistics Norway with the last update February 2008.

RESULTS

There were 4048 patients included in the analysis, with a median follow-up of 28 months. Adherence to guidelines regarding medical treatment was high. In univariate analysis, AF patients (n = 1391) had a higher risk of death than patients in sinus rhythm (n = 2657) (hazard ratio [HR] 1.181; 95% confidence interval (CI), 1.044-1.336; P = 0.008). However, after adjusting for confounding factors (age, New York Heart Association class, coronary artery disease as the main cause of HF, use of any loop diuretic, hemoglobin level, and serum creatinine), AF was no longer associated with increased risk of death (HR 1.037; 95% CI, 0.901-1.193; P = 0.619).

CONCLUSIONS

In this cohort of heart failure patients receiving optimal medical treatment at specialized HF clinics, AF was not associated with increased risk of death after adjusting for confounding factors.

A meta-analysis of the prognostic significance of atrial fibrillation in chronic heart failure

AIMS

Atrial fibrillation (AF) is one of the commonest sustained arrhythmias in chronic heart failure (CHF), although the prognostic implications of the presence of AF in CHF remain controversial. We have therefore performed this meta-analysis to study the effects of the presence of AF on mortality in CHF patients.

METHODS AND RESULTS

A systematic MEDLINE search for all randomized trials and observational studies in which the influence of AF on CHF mortality was investigated and meta-analysis of the mortality data was performed. A total of 16 studies were identified of which 7 were randomized trials and 9 were observational studies including 30,248 and 23,721 patients, respectively. An adjusted meta-analysis of the data revealed that the presence of AF is associated with an adverse effect on total mortality with an odds ratio (OR) of 1.40 [95% confidence interval (CI) 1.32-1.48, P < 0.0001] in randomized trials and an OR of 1.14 (95% CI 1.03-1.26, P < 0.05) in observational studies. This increase in mortality associated with the presence of AF was observed in subgroups of CHF patients with both preserved and impaired left ventricular (LV) systolic function.

CONCLUSION

In conclusion, meta-analysis of 16 studies involving 53,969 patients suggests that the presence of AF is associated with an adverse prognosis in CHF irrespective of LV systolic function.

Atrial fibrillation is under-recognized in chronic heart failure: insights from a heart failure cohort treated with cardiac resynchronization therapy

AIMS

Atrial fibrillation (AF) is the most common sustained arrhythmia in patients with chronic heart failure (CHF). Under-detection of asymptomatic paroxysmal AF (PAF) underestimates the true burden of AF in patients with CHF. We retrospectively studied the prevalence of asymptomatic PAF in 162 CHF patients through analysis of cardiac resynchronization therapy (CRT) device downloads to determine whether these episodes are associated with adverse outcomes.

METHODS AND RESULTS

An episode of AF was defined by mode switching on CRT devices with an atrial rate >200 for at least 30 s. Of the 101 patients thought to be persistently in sinus rhythm (SR), 27% were found to have significant paroxysms of AF, with the cumulative percentage of time in the 'mode-switch mode' (i.e. the AF burden) of 1.6 +/- 0.9%. Mortality was 19.2% in patients with newly identified PAF with hospitalization and thrombo-embolism rates of 42.3 and 2.1%, respectively, compared with mortality of 10.4% with hospitalization and thrombo-embolism rates of 41.8 and 1.9%, respectively, in patients persistently in SR (P= NS).

CONCLUSION

Analysis of data from CRT devices in a population of CHF patients with severe left ventricular dysfunction shows that a significant proportion of those perceived to be persistently in SR have undiagnosed paroxysms of AF but with relatively low burden. These episodes appear to be associated with a trend towards increased mortality but no effects on hospitalization or thrombo-embolism rates.

Atrial fibrillation in heart failure: current treatment of patients with remodeled atria

Atrial fibrillation (AF) and chronic heart failure (CHF) can be caused by each other, and therefore constitute a vicious circle. The prevalence of both conditions is about 1% in industrialized countries and increases with age. Although mortality is increased in heart failure, the additional prognostic relevance of AF in these patients is less clear. AF in patients with CHF can worsen heart failure symptoms, cause complications (eg, stroke), and is difficult to treat. Thus, prevention of AF entirely is an important goal. This review summarizes recent data concerning prognostic relevance, treatment, and means of primary and secondary prevention of AF in patients with CHF.

Pathophysiology of concomitant atrial fibrillation and heart failure: implications for management

Atrial fibrillation (AF) and heart failure (HF) are two conditions regularly encountered in clinical practice. They share many common risk factors, and are often seen concurrently in an individual patient. Global aging of the population is likely to lead to an increase in the prevalence of both AF and HF alone, as well as in their combined state. The relationship between these two diseases is not simply coincidental; clinical and experimental data have defined multiple pathophysiological mechanisms to explain how either condition contributes to the de novo development of the other. The development of AF in the setting of HF, and vice versa, is associated with clinical deterioration and worsening prognosis, which indicates the need for an improved understanding of the clinical and pathological relationships between these conditions. Future research on pharmacologic therapies, such as antiarrhythmic medications, and nonpharmacologic strategies including atrioventricular nodal ablation and pulmonary vein isolation, will help to define the optimal therapeutic approach for concurrent AF and HF. This step is vital to improve both the outcomes of patients affected by these conditions and the cost-effectiveness of their care.

Aldosterone synthase gene polymorphism as a determinant of atrial fibrillation in patients with heart failure

We analyzed the possible association between aldosterone synthase (CYP11B2) T-344C polymorphism, which is associated with increased aldosterone activity, and the prevalence of atrial fibrillation (AF) in 196 consecutive patients who had symptomatic systolic heart failure (HF; left ventricular ejection fraction <40%) for > or =3 months before recruitment. Genomic DNA was extracted from peripheral blood leukocytes using a standard protocol. Subjects were genotyped for the CYP11B2 polymorphism using the polymerase chain reaction/restriction fragment length polymorphism approach. AF was present in 63 patients (33%) with HF. We found the -344 CC genotype to be a strong independent marker for AF. Almost 1/2 (45%) of patients with this genotype had AF compared with 1/4 (27%) with -344 TT and TC genotypes (p = 0.01). A multivariate stepwise logistic regression model that included age, gender, New York Heart Association class, CYP11B2 -344CC genotype, and echocardiographic measurements of left ventricular ejection fraction, left atrial dimension, left ventricular end-diastolic diameter, and mitral regurgitation severity showed that the CYP11B2 CC genotype (adjusted for age and left atrial size) was an independent predictor of AF (adjusted odds ratio 2.35, 95% confidence interval 1.57 to 3.51, p = 0.03). In conclusion, CYP11B2 T-344C promoter polymorphism predisposes to clinical AF in patients with HF.