Dyspnea in patients with atrial fibrillation: Mechanisms, assessment and an interdisciplinary and integrated care approach

Atrial fibrillation (AF) is the most common sustained heart rhythm disorder and is often associated with symptoms that can significantly impact quality of life and daily functioning. Palpitations are the cardinal symptom of AF and many AF therapies are targeted towards relieving this symptom. However, up to two-third of patients also complain of dyspnea as a predominant self-reported symptom. In clinical practice it is often challenging to ascertain whether dyspnea represents an AF-related symptom or a symptom of concomitant cardiovascular and non-cardiovascular comorbidities, since common AF comorbidities such as heart failure and chronic obstructive pulmonary disease share similar symptoms. In addition, therapeutic approaches specifically targeting dyspnea have not been well validated. Thus, assessing and treating dyspnea can be difficult.

This review describes the latest knowledge on the burden and pathophysiology of dyspnea in AF patients. We discuss the role of heart rhythm control interventions as well as the management of AF risk factors and comorbidities with the goal to achieve maximal relief of dyspnea. Given the different and often complex mechanistic pathways leading to dyspnea, dyspneic AF patients will likely profit from an integrated multidisciplinary approach to tackle all factors and mechanisms involved. Therefore, we propose an interdisciplinary and integrated care pathway for the work-up of dyspnea in AF patients.

BMI is not independently associated with coronary artery calcification in a large single‐center CT cohort

Objective

Obesity is associated with cardiovascular disease (CVD) and CVD mortality. However, previous reports showed a paradoxical protective effect in patients with known CVD referred as "obesity paradox". Therefore, the aim of the present study was to investigate the association of body mass index (BMI) with coronary artery calcification (CAC) in a large outpatient cardiac CT cohort.

Methods

4.079 patients who underwent cardiac CT between December 2007-May 2014 were analyzed. BMI and clinical risk factors (current smoking, diabetes mellitus type 2, family history, systolic blood pressure, lipid spectrum) were assessed. Missing values were imputed using multiple imputation. CAC extent was categorized as absent (0), mild (>0-100), moderate (>100-400) and severe (>400).

Results

Multivariable multinomial logistic regression analysis, including all risk factors as independent variables, showed no association between BMI and CAC. Using absence of calcification as reference category, the odds ratios per unit increase in BMI were 1.01 for mild; 1.02 for moderate; and 1.00 for severe CAC (p-values ≥0.103).

Conclusions

No statistically significant association was observed between BMI and CAC after adjustment for other risk factors.

Research Priorities in Atrial Fibrillation Screening: A Report From a National Heart, Lung, and Blood Institute Virtual Workshop

Clinically recognized atrial fibrillation (AF) is associated with higher risk of complications, including ischemic stroke, cognitive decline, heart failure, myocardial infarction, and death. It is increasingly recognized that AF frequently is undetected until complications such as stroke or heart failure occur. Hence, the public and clinicians have an intense interest in detecting AF earlier. However, the most appropriate strategies to detect undiagnosed AF (sometimes referred to as subclinical AF) and the prognostic and therapeutic implications of AF detected by screening are uncertain. Our report summarizes the National Heart, Lung, and Blood Institute's virtual workshop focused on identifying key research priorities related to AF screening. Global experts reviewed major knowledge gaps and identified critical research priorities in the following areas: (1) role of opportunistic screening; (2) AF as a risk factor, risk marker, or both; (3) relationship between AF burden detected with long-term monitoring and outcomes/treatments; (4) designs of potential randomized trials of systematic AF screening with clinically relevant outcomes; and (5) role of AF screening after ischemic stroke. Our report aims to inform and catalyze AF screening research that will advance innovative, resource-efficient, and clinically relevant studies in diverse populations to improve the diagnosis, management, and prognosis of patients with undiagnosed AF.

P341Which patients with atrial fibrillation undergo an ablation procedure today in Europe? A report from the ESC-EHRA-EURObservational Research Programme

Aims

Great heterogeneity in rhythm control management of patients with atrial fibrillation (AF) has been described. The aim of this study was to investigate how selective the patient cohort referred for AF ablation is, as compared to the general AF population in Europe, and to describe the governing mechanisms for such selection.

Methods

Descriptive comparative statistical analyses of the baseline characteristics were performed between the cohorts of Atrial Fibrillation Ablation Long-Term (ESC-EORP EHRA AFA-LT) Registry, designed to provide a picture of contemporary real-world AF ablation, and the AF population from the AF-General (ESC-EORP EHRA AF-Gen) PilotRegistry. Data collection was performed using a web-based system.

Results

In the AFA and in the AFG pilot registries 3593 and 3049 patients were enrolled, respectively. Patients who underwent AF ablation were younger,more commonly male, and had significantly less co-morbidities. Lone AF was predominant in AFA patients who were at lower risk of stroke (CHA2DS2-VASc >5: 2.9% vs. 24.5%, all P<0.001) and bleeding (HAS-BLED ≥2: 8.5% vs. 40.5%, P<0.001) but with EHRA scores >1 and more prevalentAF-related symptoms such as palpitations, fatigue and weakness (all p<0.001)as compared to the general AF patients. AFA patients were significantly more often male, had higher LV ejection fraction (59.5% vs. 52.4%) and smaller left atrial size on echocardiogram (P<0.001 each).

Conclusions

The comparison of the patient chorts in the AFA and AFG registries showed that AF ablation in European clinical practice is mostly performed in relatively young, symptomatic and otherwise relatively healthy patients.

Acknowledgement/Funding

Abbott Vascular Int.; Amgen Cardiovascular, AstraZeneca, Bayer, Boehringer Ingelheim, Boston Scientific, Bristol Myers Squibb and Pfizer Alliance

P1903Efficacy and safety of dronedarone after recent cardioversion in patients with atrial fibrillation/flutter: a post-hoc analysis of the EURIDIS/ADONIS trials

Background

Cardioversion is commonly performed prior to antiarrhythmic drug initiation for atrial fibrillation/flutter (AF). There are limited data describing baseline differences in patients requiring cardioversion to maintain sinus rhythm compared to those who do not. Likewise, response to antiarrhythmic drugs, including dronedarone, specifically in patients requiring cardioversion has not been well defined.

Purpose

To evaluate efficacy and safety of dronedarone versus placebo in patients with non-permanent AF who had cardioversion within 5 days prior to randomization in EURIDIS/ADONIS.

Methods

To qualify for enrolment in EURIDIS/ADONIS patients were required to be in sinus rhythm for at least 1 hour preceding randomization. Of 1237 patients randomized (2:1 dronedarone to placebo), 364 needed cardioversion for study entry (dronedarone 243, placebo 121). AF recurrence was evaluated by ECG obtained during study visits, scheduled transtelephonic monitoring, or at symptom recurrence.

Results

Cardioversion patients were more likely to have rheumatic heart disease, valvular heart disease, any structural heart disease, and heart failure. Nonetheless, the median time to 1st AF recurrence was longer for dronedarone versus placebo both in cardioversion patients (50 versus 15 days, hazard ratio 0.76, 95% CI 0.59, 0.97) and no cardioversion patients (150 versus 77 days, hazard ratio 0.76, 95% CI 0.64, 0.90), as was time to 1st symptomatic recurrence (cardioversion: 347 versus 87 days, hazard ratio 0.65, 95% CI 0.49, 0.87; no cardioversion: 288 versus 120 days, hazard ratio 0.74, 95% CI 0.62, 0.90) (Figure 1). There was a trend towards fewer 1st AF hospitalizations within 12 months for dronedarone versus placebo (7.8 versus 12.4%, hazard ratio 0.60, 95% CI 0.31, 1.18 in cardioversion patients; 8.4 versus 10.4%, hazard ratio 0.74, 95% CI 0.47, 1.17 in no cardioversion patients). In cardioversion patients, rates of treatment-emergent adverse events with dronedarone versus placebo were 64 versus 66%, serious treatment-emergent adverse events were 19 versus 26%, permanent discontinuations were 9 versus 6%, and deaths were 0 versus 1%.

Conclusions

1) Cardioversion-requiring patients have more baseline structural heart disease and overall shorter time to AF recurrence. 2) Dronedarone effectively delayed 1st AF recurrence versus placebo in patients with or without recent cardioversion. 3) Safety of dronedarone in cardioversion patients was similar to placebo and overall observations from EURIDIS/ADONIS despite baseline differences in comorbidities.

Acknowledgement/Funding

Sanofi, New York, New York, United States of America

Nightly sleep apnea severity in patients with atrial fibrillation: Potential applications of long-term sleep apnea monitoring

In patients with atrial fibrillation (AF), the prevalence of moderate-to-severe sleep-disordered breathing (SDB) ranges between 21% and 72% and observational studies have demonstrated that SDB reduces the efficacy of rhythm control strategies, while treatment with continuous positive airway pressure lowers the rate of AF recurrence. Currently, the number of apneas and hypopneas per hour (apnea-hypopnea-index, AHI) determined during a single overnight sleep study is clinically used to assess the severity of SDB. However, recent studies suggest that SDB-severity in an individual patient is not stable over time but exhibits a considerable night-to-night variability which cannot be detected by only one overnight sleep assessment. Nightly SDB-severity assessment rather than the single-night diagnosis by one overnight sleep study may better reflect the exposure to SDB-related factors and yield a superior metric to determine SDB-severity in the management of AF. In this review we discuss mechanisms of night-to-night SDB variability, arrhythmogenic consequences of night-to-night SDB variability, strategies for longitudinal assessment of nightly SDB-severity and clinical implications for screening and management of SDB in AF patients.

Effect of Systemic Hypertension With Versus Without Left Ventricular Hypertrophy on the Progression of Atrial Fibrillation (from the Euro Heart Survey)

Hypertension is a risk factor for both progression of atrial fibrillation (AF) and development of AF-related complications, that is major adverse cardiac and cerebrovascular events (MACCE). It is unknown whether left ventricular hypertrophy (LVH) as a consequence of hypertension is also a risk factor for both these end points. We aimed to assess this in low-risk AF patients, also assessing gender-related differences. We included 799 patients from the Euro Heart Survey with nonvalvular AF and a baseline echocardiogram. Patients with and without hypertension were included. End points after 1 year were occurrence of AF progression, that is paroxysmal AF becoming persistent and/or permanent AF, and MACCE. Echocardiographic LVH was present in 33% of 379 hypertensive patients. AF progression after 1 year occurred in 10.2% of 373 patients with rhythm follow-up. In hypertensive patients with LVH, AF progression occurred more frequently as compared with hypertensive patients without LVH (23.3% vs 8.8%, p = 0.011). In hypertensive AF patients, LVH was the most important multivariably adjusted determinant of AF progression on multivariable logistic regression (odds ratio 4.84, 95% confidence interval 1.70 to 13.78, p = 0.003). This effect was only seen in male patients (27.5% vs 5.8%, p = 0.002), while in female hypertensive patients, no differences were found in AF progression rates regarding the presence or absence of LVH (15.2% vs 15.0%, p = 0.999). No differences were seen in MACCE for hypertensive patients with and without LVH. In conclusion, in men with hypertension, LVH is associated with AF progression. This association seems to be absent in hypertensive women.

Prevalence of Pathogenic Gene Mutations and Prognosis Do Not Differ in Isolated Left Ventricular Dysfunction Compared With Dilated Cardiomyopathy

Background:

Genetic evaluation is recommended in patients with unexplained dilated cardiomyopathy (DCM), but its diagnostic yield and prognostic relevance in unexplained isolated left ventricular dysfunction (LVdys) is unknown.

Methods and Results:

A total of 127 LVdys and 262 DCM patients underwent genetic screening. Long-term outcome consisted of a combined end point of life-threatening arrhythmia, heart transplantation, and death. At baseline, LVdys patients were younger and had less frequently New York Heart Association class ≥3 when compared with DCM (55±13 versus 58±12; P =0.019 and 21% versus 36%; P =0.003, respectively). The prevalence of familial disease and pathogenic mutations was similar in LVdys and DCM (45% versus 40%; P =0.37 and 19% versus 17%; P =0.61, respectively). After a follow-up of 56 (31–82) months, outcome did not differ in LVdys compared with DCM patients (hazard ratio, 0.83; 95% confidence interval, 0.47–1.45; P =0.51). Overall, outcome was less favorable in patients with a genetic mutation or familial disease when compared with those without (hazard ratio, 2.7; 95% confidence interval, 1.07–7.7; P =0.048 and hazard ratio, 2.2; 95% confidence interval, 1.2–4.2; P =0.013, respectively). Thus, the diagnostic yield of genetic testing in LVdys and DCM is similarly high. The presence of a gene mutation or familial predisposition results in an equally worse prognosis.

Conclusions:

Genetic evaluation is advised in LVdys patients and should not merely be restricted to DCM.

Clinical and echocardiographic determinants in bicuspid aortic dilatation: Results from a longitudinal observational study

Bicuspid aortic valve (BAV) disease is associated with aortic dilatation. Timing of follow-up and surgery is challenging. Hence, there is an unmet clinical need for additional risk stratification. It is unclear whether valve morphology is associated with dilatation rates. Therefore, the objective of this study was to examine the association between clinical and echocardiographic determinants (including valve morphology) and aortic dimension and the progression rate of dilatation.Aortic dimensions were assessed on serial echocardiographic images between 1999 and 2014 in a population of 392 patients with BAVs in a tertiary care center in the Netherlands. Analyses using mixed linear models were performed.Mean age of participants was 48 ± 17 years and 69% were male. BAV morphology was associated with aortic dimensions, as well as age, sex, BSA, and valvular dysfunction. Tubular ascending aorta, sinus of Valsalva, and sinotubular junction showed a dilatation rate of 0.32, 0.18, and 0.06 mm/year, respectively. Dilatation rate was not associated with valve morphology.In the present study, there is no association between BAV morphology and aortic dilatation rates. Therefore, morphology is of limited use in prediction of aortic growth. Discovering fast progressors remains challenging.

Acute chest pain in the high-sensitivity cardiac troponin era: A changing role for noninvasive imaging?

Management of patients with acute chest pain remains challenging. Cardiac biomarker testing reduces the likelihood of erroneously discharging patients with acute myocardial infarction (AMI). Despite normal contemporary troponins, physicians have still been reluctant to discharge patients without additional testing. Nowadays, the extremely high negative predictive value of current high-sensitivity cardiac troponin (hs-cTn) assays challenges this need. However, the decreased specificity of hs-cTn assays to diagnose AMI poses a new problem as noncoronary diseases (eg, pulmonary embolism, myocarditis, cardiomyopathies, hypertension, renal failure, etc) may also cause elevated hs-cTn levels. Subjecting patients with noncoronary diseases to unnecessary pharmacological therapy or invasive procedures must be prevented. Attempts to improve the positive predictive value to diagnose AMI by defining higher initial cutoff values or dynamic changes over time inherently lower the sensitivity of troponin assays. In this review, we anticipate a potential changing role of noninvasive imaging from ruling out myocardial disease when troponin values are normal toward characterizing myocardial disease when hs-cTn values are (mildly) abnormal.

Identifying delayed left ventricular lateral wall activation in patients with non-specific intraventricular conduction delay using coronary venous electroanatomical mapping

Background

Delayed left ventricular (LV) lateral wall activation is considered the electrical substrate that characterises patients suitable for cardiac resynchronisation therapy (CRT). Although typically associated with left bundle branch block, delayed LV lateral wall activation may also be present in patients with non-specific intraventricular conduction delay (IVCD). We assessed LV lateral wall activation in a cohort of CRT candidates with IVCD using coronary venous electroanatomical mapping, and investigated whether baseline QRS characteristics on the ECG can identify delayed LV lateral wall activation in this group of patients.

Methods

Twenty-three consecutive CRT candidates with IVCD underwent intra-procedural coronary venous electroanatomical mapping using EnSite NavX. Electrical activation time was measured in milliseconds from QRS onset and expressed as percentage of QRS duration. LV lateral wall activation was considered delayed if maximal activation time measured at the LV lateral wall (LVLW-AT) exceeded 75 % of the QRS duration. QRS morphology, duration, fragmentation, axis deviation, and left anterior/posterior fascicular block were assessed on baseline ECGs.

Results

Delayed LV lateral wall activation occurred in 12/23 patients (maximal LVLW-AT = 133 ± 20 ms [83 ± 5 % of QRS duration]). In these patients, the latest activated region was consistently located on the basal lateral wall. QRS duration, and prevalence of QRS fragmentation and left/right axis deviation, and left anterior/posterior fascicular block did not differ between patients with and without delayed LV lateral wall activation.

Conclusion

Coronary venous electroanatomical mapping can be used at the time of CRT implantation to determine the presence of delayed LV lateral wall activation in patients with IVCD. QRS characteristics on the ECG seem unable to identify delayed LV lateral wall activation in this subgroup of patients.

The role of cardiovascular magnetic resonance imaging and computed tomography angiography in suspected non-ST-elevation myocardial infarction patients: design and rationale of the CARdiovascular Magnetic rEsoNance imaging and computed Tomography Angiography (CARMENTA) trial

BACKGROUND

Although high-sensitivity cardiac troponin (hs-cTn) substantially improves the early detection of myocardial injury, it lacks specificity for acute myocardial infarction (MI). In suspected non-ST-elevation MI, invasive coronary angiography (ICA) remains necessary to distinguish between acute MI and noncoronary myocardial disease (eg, myocarditis), unnecessarily subjecting the latter to ICA and associated complications. This trial investigates whether implementing cardiovascular magnetic resonance (CMR) or computed tomography angiography (CTA) early in the diagnostic process may help to differentiate between coronary and noncoronary myocardial disease, thereby preventing unnecessary ICA.

STUDY DESIGN

In this prospective, single-center, randomized controlled clinical trial, 321 consecutive patients with acute chest pain, elevated hs-cTnT, and nondiagnostic electrocardiogram are randomized to 1 of 3 strategies: (1) CMR, or (2) CTA early in the diagnostic process, or (3) routine clinical management. In the 2 investigational arms of the study, results of CMR or CTA will guide further clinical management. It is expected that noncoronary myocardial disease is detected more frequently after early noninvasive imaging as compared with routine clinical management, and unnecessary ICA will be prevented. The primary end point is the total number of patients undergoing ICA during initial admission. Secondary end points are 30-day and 1-year clinical outcome (major adverse cardiac events and major procedure-related complications), time to final diagnosis, quality of life, and cost-effectiveness.

CONCLUSION

The CARMENTA trial investigates whether implementing CTA or CMR early in the diagnostic process in suspected non-ST-elevation MI based on elevated hs-cTnT can prevent unnecessary ICA as compared with routine clinical management, with no detrimental effect on clinical outcome.

The burden of atrial fibrillation in the Netherlands

BACKGROUND

Atrial fibrillation (AF) is the most common sustained atrial arrhythmia and it is independently associated with an increased morbidity and mortality. As a result of the high prevalence of AF, the economic and clinical impact of the disease is substantial. This study describes the economic and clinical impact of AF in the Netherlands.

METHODS

Epidemiological data on AF in the Netherlands were projected on population estimates of the Netherlands in 2009 and combined with data on the cost of AF and its interventions.

RESULTS

Overall prevalence of AF in the Netherlands is 5.5% in the population over 55 years, corresponding to about 250,000 AF patients. The prevalence increases with age, and the mean age of AF patients is 69.3 years. Incidence of AF in the Netherlands varies with age, from 1188 new cases in the age group of 55 to 59 up to 7074 new cases in the age group 75 to 79. Total new cases amounts to 45,085 patients per year in the Netherlands. Total costs of AF in the Netherlands are <euro> 583 million, of which the majority (70%) were accounted for by hospitalisations and in-hospital procedures. Pharmacotherapeutic management of AF totalled <euro> 17 million in the Netherlands in 2009.

DISCUSSION

AF is a serious disease with a high clinical and economic burden, especially due to hospitalisations as a result of cardiovascular events. The number of patients with AF in the Netherlands is considerable and will increase with the ageing population in the future.

Vectorcardiography as a Tool for Easy Optimization of Cardiac Resynchronization Therapy in Canine Left Bundle Branch Block Hearts

Background—

In cardiac resynchronization therapy (CRT), optimization of left ventricular (LV) stimulation timing is often time consuming. We hypothesized that the QRS vector in the vectorcardiogram (VCG) reflects electric interventricular dyssynchrony, and that the QRS vector amplitude (VA QRS ), halfway between that during left bundle branch block (LBBB) and LV pacing, reflects optimal resynchronization, and can be used for easy optimization of CRT.

Methods and Results—

In 24 canine hearts with LBBB (12 acute, 6 with heart failure, and 6 with myocardial infarction), the LV was paced over a wide range of atrioventricular (AV) delays. Surface ECGs were recorded from the limb leads, and VA QRS was calculated in the frontal plane. Mechanical interventricular dyssynchrony (MIVD) was determined as the time delay between upslopes of LV and right ventricular pressure curves, and systolic function was assessed as LV dP/dt max . VA QRS and MIVD were highly correlated ( r =0.94). The VA QRS halfway between that during LV pacing with short AV delay and intrinsic LBBB activation accurately predicted the optimal AV delay for LV pacing (1 ms; 95% CI, –5 to 8ms). Increase in LV dP/dt max at the VCG predicted AV delay was only slightly lower than the highest observed ∆LV dP/dt max (–2.7%; 95% CI, –3.6 to –1.8%). Inability to reach the halfway value of VA QRS during simultaneous biventricular pacing (53% of cases) was associated with suboptimal hemodynamic response, which could be corrected by sequential pacing.

Conclusions—

The VA QRS reflects electric interventricular dyssynchrony and accurately predicts optimal timing of LV stimulation in canine LBBB hearts. Therefore, VCG may be useful as a reliable and easy tool for individual optimization of CRT.

Antidepressive effect of mirtazapine in post-myocardial infarction depression is associated with soluble TNF-R1 increase: data from the MIND-IT

BACKGROUND

Depressive disorder after myocardial infarction (MI) is associated with increased cardiac morbidity and mortality. Immune activity such as inflammation might be implicated as an underlying mechanism. The purpose of this study is to investigate whether the response to an antidepressant in post-MI depression is associated with changes of inflammatory markers in serum.

METHODS

In a double-blind placebo-controlled study with mirtazapine 30 mg/day (50 patients), the antidepressive effect was related to immune activation parameters. The cytokines interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α), the soluble cytokine receptors sIL-6R, sTNF-R1 and sTNF-R2, and the inflammation-sensitive plasma proteins C-reactive protein and neopterin were assessed.

RESULTS

Subgroup analyses revealed a highly significant correlation of pronounced sTNF-R1 increase with a decrease in depressive symptoms in antidepressant responders.

CONCLUSION

Significant effects on inflammation accompany the therapeutic efficacy of mirtazapine in contrast to the therapeutic efficacy of placebo and the nontherapeutic efficacy of mirtazapine.