Atrial dyssynchrony syndrome: an overlooked phenomenon and a potential cause of 'diastolic' heart failure

PR prolongation as a predictor of atrial fibrillation onset: A state-of-the-art review

First-degree atrioventricular block (1-AVB), characterized by a PR interval exceeding 200 milliseconds, has traditionally been perceived as a benign cardiac condition. Recently, this perception has been challenged by investigations that indicate a potential association between PR prolongation and an elevated risk of atrial fibrillation (AF). To consolidate these findings, we performed a comprehensive review to assess the available evidence indicating a relationship between these two conditions. We searched MEDLINE and EMBASE databases as well as manually searched references of retrieved articles. We selected 18 cohort studies/meta-analyses involving general and special populations. Consistent findings across expansive cohort studies reveal that incremental increases in the PR interval may serve as an independent risk factor for AF. However, our analyses underscore the need for further research into the association between 1-AVB, defined by a specified PR interval cutoff, and the risk of AF.

Advances in device-based treatment of heart failure with preserved ejection fraction: evidence from clinical trials

Heart failure with preserved ejection fraction (HFpEF) is a group of clinical syndromes that exhibit a remarkably heterogeneous phenotype, characterized by symptoms and signs of heart failure, left ventricular diastolic dysfunction, elevated levels of natriuretic peptides, and an ejection fraction greater than or equal to 50%. With the aging of the population and the escalating prevalence of hypertension, obesity, and diabetes, the incidence of HFpEF is progressively rising. Drug therapy options for HFpEF are currently limited, and the associated high risk of cardiovascular mortality and heart failure rehospitalization significantly impact patients' quality of life and longevity while imposing a substantial economic burden on society. Recent research indicates that certain device-based therapies may serve as valuable adjuncts to drug therapy in patients with specific phenotypes of HFpEF, effectively improving symptoms and quality of life while reducing the risk of readmission for heart failure. These include inter-atrial shunt and greater splanchnic nerve ablation to reduce left ventricular filling pressure, implantable heart failure monitor to guide diuresis, left atrial pacing to correct interatrial dyssynchrony, cardiac contractility modulation to enhance cardiac calcium handling, as well as renal denervation, baroreflex activation therapy, and vagus nerve stimulation to restore the autonomic imbalance. In this review, we provide a comprehensive overview of the mechanisms and clinical evidence pertaining to these devices, with the aim of enhancing therapeutic strategies for HFpEF.

Alternative atrial pacing site to improve cardiac function: focus on Bachmann's bundle pacing

Pacing from the right atrial appendage (RAA) prolongs the P wave duration and can induce interatrial and especially left-sided atrio-ventricular dyssynchrony. Pacing from Bachmann's bundle closely reproduces normal physiology and has the potential to avoid the electromechanical dysfunction associated with conventional RAA pacing. Interatrial conduction delay is associated with an increased risk of stroke, heart failure, and death. In addition to a reduction in atrial fibrillation, Bachmann's bundle pacing has emerging applications as a hemodynamic pacing modality. This review outlines the pathophysiology of atrial conduction disturbances and their potential remedies and provides the reader with a practical guide to implementing Bachmann's bundle pacing with an emphasis on the recapitulation of normal electrical and mechanical function.

Asymmetric remodeling between the left and right atria in patients with advanced interatrial block and atrial fibrillation

BACKGROUND

Advanced interatrial block (A-IAB) on electrocardiography (ECG) represents the conduction delay between the left and right atria. We investigated the association of A-IAB with left and right atrial (LA/RA) remodeling in patients with atrial fibrillation (AF).

METHODS

We enrolled 74 patients who underwent ECG, cardiac computed tomography (CCT), and echocardiography during sinus rhythm before catheter ablation of AF. A-IAB was defined as P-wave duration ≥120 ms with a biphasic morphology in leads III and aVF or notched morphology in lead II. We compared the maximum and minimum LA/RA volume indices (max and min LAV/RAVI), LA/RA expansion index (LAEI/RAEI), and total, passive, and active LA/RA emptying fraction (LAEF/RAEF) between patients with and without A-IAB.

RESULTS

Of the 74 patients (mean age, 64.3 ± 9.6 years), 35 (47%) showed A-IAB. Patients with A-IAB had a significantly higher likelihood of hypertension and left ventricular diastolic dysfunction than those without. Patients with A-IAB had significantly larger max (69.2 [60.7-79.7]mL/m2 vs. 60.9 [50.4-68.3]mL/m2, P < 0.01) and min (44.0 [37.2-52.1]mL/m2 vs. 34.1 [29.2-43.5]mL/m2, P < 0.01) LAVI than those without. The max and min RAVI were not significantly different between groups. LAEI (55.1 [48.2-78.5]% vs. 72.1 [57.8-84.8]%, P < 0.05), total LAEF (35.5 [32.5-44.0]% vs. 41.9 [36.6-45.9]%, P < 0.05), and passive LAEF (12.2 [10.0-14.4]% vs. 15.5 [11.2-19.6]%, P < 0.05) were significantly lower in patients with A-IAB than without.

CONCLUSIONS

A-IAB was associated with LA, but not RA enlargement, in patients with AF. A-IAB may indicate LA functional remodeling in the reservoir and conduit phases.

Electrocardiographic Features of Left Ventricular Diastolic Dysfunction and Heart Failure With Preserved Ejection Fraction: A Systematic Review

Background: Electrocardiographic features are well-known for heart failure with reduced ejection fraction (HFrEF), but not for left ventricular diastolic dysfunction (LVDD) and heart failure with preserved ejection fraction (HFpEF). As ECG features could help to identify high-risk individuals in primary care, we systematically reviewed the literature for ECG features diagnosing women and men suspected of LVDD and HFpEF. Methods and Results: Among the 7,127 records identified, only 10 studies reported diagnostic measures, of which 9 studied LVDD. For LVDD, the most promising features were T-end-P/(PQ*age), which is the electrocardiographic equivalent of the passive-to-active filling (AUC: 0.91-0.96), and repolarization times (QTc interval ≥ 350 ms, AUC: 0.85). For HFpEF, the Cornell product ≥ 1,800 mm*ms showed poor sensitivity of 40% (AUC: 0.62). No studies presented results stratified by sex. Conclusion: Electrocardiographic features are not widely evaluated in diagnostic studies for LVDD and HFpEF. Only for LVDD, two ECG features related to the diastolic interval, and repolarization measures showed diagnostic potential. To improve diagnosis and care for women and men suspected of heart failure, reporting of sex-specific data on ECG features is encouraged.

Current Status of Pharmacologic and Nonpharmacologic Therapy in Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a significantly symptomatic disease and has a poor prognosis similar to that of heart failure with reduced ejection fraction (HFrEF). Contrary to HFrEF, HFpEF is difficult to diagnose, and the recommended diagnostic algorithm of HFpEF is complicated. Several therapies for HFpEF have failed to reduce mortality or morbidity. HFpEF is thought to be a complex and heterogeneous systemic disorder that has various phenotypes and multiple comorbidities. Therefore, therapeutic strategies of HFpEF need to change depending on the phenotype of the patient. This review highlights the pharmacologic and nonpharmacologic treatment of HFpEF.

Cardiac Stimulation in the Third Millennium: Where Do We Head from Here?

Over the years, pacemakers have evolved from a life-saving tool to prevent asystole to a device to treat heart rhythm disorders and heart failure, aiming at improving both cardiac function and clinical outcomes. Cardiac stimulation nowadays aims to correct the electrophysiologic roots of mechanical inefficiency in different structural heart diseases. This has led to awareness of the concealed risks of customary cardiac pacing that can inadvertently cause atrioventricular and inter-/intra-ventricular dyssynchrony, and has promoted the development of new pacing modalities and the use of stimulation sites different from the right atrial appendage and the right ventricular apex. The perspective of truly physiologic pacing is the leading concept of the continued research in the past 30 years, which has made cardiac stimulation procedure more sophisticated and challenging. In this article, we analyze the emerging evidence in favor of the available strategies to achieve an individualized physiologic setting in bradycardia pacing.

Pacing devices to treat bradycardia: current status and future perspectives

Introduction: Cardiac stimulation evolved from life-saving devices to prevent asystole to the treatment of heart rhythm disorders and heart failure, capable of remote patient and disease-progression monitoring. Cardiac stimulation nowadays aims to correct the electrophysiologic roots of mechanical inefficiency in different structural heart diseases.Areas covered: Clinical experience, as per available literature, has led to awareness of the concealed risks of customary cardiac pacing, that can inadvertently cause atrio-ventricular and inter/intra-ventricular dyssynchrony. New pacing modalities have emerged, leading to a new concept of what truly represents 'physiologic pacing' beyond maintenance of atrio-ventricular coupling. In this article we will analyze the emerging evidence in favor of the available strategies to achieve an individualized physiologic setting in bradycardia pacing, and the hints of future developments.Expert opinion: 'physiologic stimulation' technologies should evolve to enable an effective and widespread adoption. In one way new guiding catheters and the adoption of electrophysiologic guidance and non-fluoroscopic lead implantation are needed to make His-Purkinje pacing successful and effective at long term in a shorter procedure time; in the other way leadless stimulation needs to upgrade to a superior physiologic setting to mimic customary DDD pacing and possibly His-Purkinje pacing.

Transitioning from Preclinical to Clinical Heart Failure with Preserved Ejection Fraction: A Mechanistic Approach

To better understand heart failure with preserved ejection fraction (HFpEF), we need to better characterize the transition from asymptomatic pre-HFpEF to symptomatic HFpEF. The current emphasis on left ventricular diastolic dysfunction must be redirected to microvascular inflammation and endothelial dysfunction that leads to cardiomyocyte remodeling and enhanced interstitial collagen deposition. A pre-HFpEF patient lacks signs or symptoms of heart failure (HF), has preserved left ventricular ejection fraction (LVEF) with incipient structural changes similar to HFpEF, and possesses elevated biomarkers of cardiac dysfunction. The transition from pre-HFpEF to symptomatic HFpEF also involves left atrial failure, pulmonary hypertension and right ventricular dysfunction, and renal failure. This review focuses on the non-left ventricular mechanisms in this transition, involving the atria, right heart cavities, kidneys, and ultimately the currently accepted driver—systemic inflammation. Impaired atrial function may decrease ventricular hemodynamics and significantly increase left atrial and pulmonary pressure, leading to HF symptoms, irrespective of left ventricle (LV) systolic function. Pulmonary hypertension and low right-ventricular function are associated with the incidence of HF. Interstitial fibrosis in the heart, large arteries, and kidneys is key to the pathophysiology of the cardiorenal syndrome continuum. By understanding each of these processes, we may be able to halt disease progression and eventually extend the time a patient remains in the asymptomatic pre-HFpEF stage.

Electrocardiographic characteristics in patients with heart failure and normal ejection fraction: A systematic review and meta-analysis

BACKGROUND

Little is known about ECG abnormalities in patients with heart failure and normal ejection fraction (HeFNEF) and how they relate to different etiologies or outcomes.

METHODS AND RESULTS

We searched the literature for peer-reviewed studies describing ECG abnormalities in HeFNEF other than heart rhythm alone. Thirty five studies were identified and 32,006 participants. ECG abnormalities reported in patients with HeFNEF include atrial fibrillation (prevalence 12%-46%), long PR interval (11%-20%), left ventricular hypertrophy (LVH, 10%-30%), pathological Q waves (11%-18%), RBBB (6%-16%), LBBB (0%-8%), and long JTc (3%-4%). Atrial fibrillation is more common in patients with HeFNEF compared to those with heart failure and reduced ejection fraction (HeFREF). In contrast, long PR interval, LVH, Q waves, LBBB, and long JTc are more common in patients with HeFREF. A pooled effect estimate analysis showed that QRS duration ≥120 ms, although uncommon (13%-19%), is associated with worse outcomes in patients with HeFNEF.

CONCLUSIONS

There is high variability in the prevalence of ECG abnormalities in patients with HeFNEF. Atrial fibrillation is more common in patients with HeFNEF compared to those with HeFREF. QRS duration ≥120 ms is associated with worse outcomes in patients with HeFNEF. Further studies are needed to address whether ECG abnormalities correlate with different phenotypes in HeFNEF.

Atrioventricular dromotropathy: evidence for a distinctive entity in heart failure with prolonged PR interval?

Heart failure (HF) is often accompanied by atrioventricular (AV) conduction disturbance, represented by prolongation of the PR interval on the electrocardiogram. Studies suggest that PR prolongation exists in at least 10% of HF patients, and it seems more prevalent in the presence of prolonged QRS duration. A prolonged PR interval may result in elevated left ventricular (LV) end-diastolic pressure, diastolic mitral regurgitation, and reduced LV pump function. This seems especially the case in patients with heart disease, in whom it is associated with an increased risk for atrial fibrillation, advanced AV heart block, HF, and death. These findings point towards the importance of proper AV coupling in HF patients. A few studies, strongly differing in design, suggest that restoration of AV coupling in patients with PR prolongation by pacing improves cardiac function and clinical outcomes. These observations argue for AV-dromotropathy as a potential target for pacing therapy, but other studies show inconsistent results. Given its potential clinical implications, restoration of AV coupling by pacing warrants further investigation. Additional possible future research goals include assessing different techniques to measure compromised AV coupling, determine the best site(s) of ventricular pacing, and assess a potential influence of diastolic mitral regurgitation in the efficacy of such therapy.

Atrial resynchronization therapy in patients with atrial fibrillation and heart failure with and without systolic left ventricular dysfunction: a pilot study

BACKGROUND

We examined the long-term (≥ 5 years) outcomes of dual-site atrial pacing (DAP) when added to background antiarrhythmic drugs (AADs) and/or ablation in patients with refractory atrial fibrillation (AF) and heart failure (HF).

METHODS

Seventy-three patients with HF (mean NYHA HF class of 2.5) and AF refractory to AADs and/or ablation were implanted with DAP systems to achieve biatrial electrical and mechanical resynchronization (ART) and rhythm control (RC).

RESULTS

Thirty-eight patients with refractory AF and HF with preserved ejection fraction (HFpEF) and 35 with reduced ejection fraction (HFrEF) were enrolled. HFpEF patients had higher left ventricular ejection fraction compared to HFrEF (53 ± 5 vs. 31 ± 10% p < 0.001). Median follow-up for survival was 9.3 years (mean 9.0 years, SE 0.63) and was similar across subgroups (p = 0.127). After DAP, 87% maintained RC with improvement in NYHA HF class (mean 1.8) at 3 years. RC was similar in HFpEF compared with HFrEF patients (89 vs. 85% respectively, p = NS) and in paroxysmal versus persistent AF (90 vs. 85% respectively, p = NS). Total survival was superior in HFpEF compared HFrEF patients (75% in HFpEF vs. 45% in HFrEF at 5 years, and 60% in HFpEF vs. 34% in HFrEF at 10 years, p = 0.036). Survival trended to be better in patients with RC than those without RC (75 vs. 54% respectively at 5 years, p = .13).

CONCLUSIONS

ART using DAP as add on therapy improved HF and established long-term RC in many patients with HFrEF and HFpEF with refractory AF. Long-term survival rates were superior in HFpEF than HFrEF.

Low interatrial septal pacing: A simple method

Background

Sinus node disease is associated with widespread structural and electrophysiological changes in the atria in addition to abnormalities at the sinus node. The atrial conduction disorder in patients with atrial pacing results in higher incidence of atrial fibrillation. Studies have shown that low interatrial septal pacing is superior to right atrial appendage pacing in preventing persistent or permanent atrial fibrillation in these patients. However, implantation of active fixation lead in low interatrial septal position is difficult and time consuming with conventional stylet, inhibiting application of this method in routine practice.

Method

The technique of implanting atrial pacing lead in low interatrial septum with hand-made stylet is presented in this study with emphasis on fluoroscopic landmark and electrocardiographic P wave pattern.

Results

The results indicate acute and short-term success of low interatrial septal pacing in 10 patients out of 11 patients without major complications. Pacing parameters during implantation and 3 months post procedure were within normal limits.

Conclusion

The initial favorable results of this study indicate low interatrial septal pacing with conventional active fixation lead using fluoroscopic landmark and electrocardiographic characteristics is feasible and reproducible with a simple technique.

Targets for Heart Failure With Preserved Ejection Fraction

Heart failure (HF) with preserved ejection fraction (HFPEF) is responsible for half of all HF cases and will be the most common form of HF within the next 5 years. Previous studies of pharmacological agents in HFPEF have proved neutral or negative, in part due to phenotypic heterogeneity and complex underlying mechanisms. This review summarizes the key molecular and cellular pathways characterized in HFPEF as well as current and future therapies that target these mechanisms.

Left atrial changes in early stages of heart failure with preserved ejection fraction

BACKGROUND AND AIM

Increased left atrial (LA) mass was introduced as a compensatory mechanism in heart failure (HF) patients. Furthermore, atrial conduction time and LA emptying fraction is are deteriorated in HF with preserved ejection fraction (HFpEF). The aim of this study was to assess the early LA changes in HFpEF patients.

METHODS

In 79 consecutive patients with HFpEF (age 61±8 years, NYHA class I-III, LV EF ≥45%), a complete 2-dimensional, M-mode, and Doppler echocardiographic study was performed. According to the diastolic dysfunction (DD), patients were divided into three groups: Group I-29 healthy subjects (control group); Group II-HFpEF patients with mild DD; and Group III-HFpEF patients with moderate DD.

RESULTS

The LV mass was increased (P<.05), septal s', lateral s', septal and lateral MAPSE were decreased (P<.05, for all), E/e' ratio was increased (P<.001), LA mass and minimal volume were increased (P<.001, P<.05), LA emptying fraction was decreased (P<.05), and LA dyssynchrony was deteriorated (P<.05) in patients with mild DD compared to controls. These changes were of the same nature in patients with moderate LV DD.

CONCLUSIONS

In early stage of DD, in patients with HFpEF, in addition to LV hypertrophy and compromised LV longitudinal systolic function, the LA emptying fraction is reduced, LA mass and LAV min are increased and LA dyssynchrony is significant, despite normal LA dimensions. These findings suggest early LA function deterioration irrespective of normal cavity measurements, hence a need for optimum therapy.

A simple method for Bachmann's bundle pacing with indigenous modification of J-stylet

Background

Pacing in the Bachmann's bundle (BB) area (upper atrial septum) appears superior to right atrial appendage or free wall stimulation for the prevention of paroxysmal atrial fibrillation in patients with atrial conduction delay. However, insertion of active fixation lead in the upper atrial septal position is difficult and time consuming with conventional stylet, inhibiting application of this pacing method in routine practice.

Methods

The technique of positioning the atrial lead in BB with hand-made stylet is presented with emphasis on electrocardiographic P-wave pattern and fluoroscopic landmarks.

Results

The results demonstrate an acute implantation and short-term success of BB pacing of 14 patients out of 15 patients without major complications. Pacing parameters at implantation and 3 months postprocedure were noted which were within normal limits.

Conclusion

These favorable initial results indicate that the positioning of active fixation atrial lead in BB with fluoroscopic landmarks is feasible and reproducible with a simple technique.

Cardiovascular Imaging in the Electrophysiology Laboratory

In recent years, rapid technological advances have allowed the development of new electrophysiological procedures that would not have been possible without the parallel development of imaging techniques used to plan and guide these procedures and monitor their outcomes. Ablation of atrial fibrillation is among the interventions with the greatest need for imaging support. Echocardiography allows the appropriate selection of patients and the detection of thrombi that would contraindicate the intervention; cardiac magnetic resonance imaging and computed tomography are also essential in planning this procedure, by allowing a detailed anatomical study of the pulmonary veins. In addition, in cardiac resynchronization therapy, echocardiography plays a central role in both patient selection and, later, in device adjustment and in assessing the effectiveness of the technique. More recently, ablation of ventricular tachycardias has been established as a treatment option; this would not be possible without planning using an imaging study such as cardiac magnetic resonance imaging of myocardial scarring.

Left ventricular longitudinal systolic dysfunction is associated with right atrial dyssynchrony in heart failure with preserved ejection fraction

OBJECTIVE

We aimed in this study to assess the role of longitudinal left ventricular (LV) systolic function in heart failure with preserved ejection fraction (HFpEF) in delayed intra- and interatrial conduction time.

METHODS

In 85 consecutive patients with HFpEF (age 60±11 years, ejection fraction [EF] ≥45%), a complete M-mode echocardiographic and tissue Doppler imaging (TDI) study was performed. The times from the onset of the P wave on the ECG to the beginning of the A' wave (PA) from the lateral and septal mitral and tricuspid annuli on TDI were recorded. The difference between these intervals gave the intra- and interatrial dyssynchrony. Based on mitral annular plane systolic excursion (MAPSE), patients were classified as having HFpEF with impaired (MAPSE ≤1.2 cm) or normal (MAPSE >1.2 cm) longitudinal systolic function.

RESULTS

Patients with impaired MAPSE were older (p<0.001), had higher LV mass index (p<0.001), greater left atrial (LA) minimum volume (p=0.007), reduced left atrial EF (p<0.001), higher E/e' ratio (p=0.002), reduced lateral and septal e' wave (p=0.005 and p=0.006, respectively), prolonged tricuspid PA' (p=0.03) and significantly increased right atrial (RA) dyssynchrony (p=0.001) compared with normal MAPSE. MAPSE correlated with RA dyssynchrony (r=-0.40, p<0.001) but not with interatrial and LA dyssynchrony.

CONCLUSION

In patients with HFpEF and impaired MAPSE, RA dyssynchrony is increased, compared to those with normal MAPSE. As patients with RA dyssynchrony are at higher risk for arrhythmia, assessment of this dyssynchrony may help to improve treatment, as well as to predict outcome in these patients.

New echocardiographic predictors of clinical outcome in patients presenting with heart failure and a preserved left ventricular ejection fraction: a subanalysis of the Ka (Karolinska) Ren (Rennes) Study

OBJECTIVES

To identify electrocardiographic and echocardiographic predictors of mortality and hospitalizations for heart failure (HF) in the KaRen study.

BACKGROUND

KaRen is a prospective, observational study of the long-term outcomes of patients presenting with heart failure and a preserved ejection fraction (HFpEF).

METHOD

We identified 538 patients who presented with acute cardiac decompensation, a >100 pg/mL serum b-type natriuretic peptide (BNP) or >300 pg/mL N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration and a left ventricular ejection fraction (LVEF) >45%. After 4-8 weeks of standard treatment, 413 patients (mean age = 76 ± 9 years, 55.9% women) returned for analyses of their clinical status, laboratory screen, and detailed electrocardiographic and Doppler echocardiographic recordings. They were followed for a mean of 28 months thereafter. The primary study endpoint was time to death from all causes or first hospitalization for heart failure.

RESULTS

Mean LVEF was 62.4 ± 6.9% and median NT-proBNP 1410 pmol/L. PR interval >200 ms was present in 11.2% of patients and 14.9% had a >120 ms QRS duration, with left bundle branch block in only 6.3%. Over a mean follow-up of 28 months, 177 patients (42.9%) reached a primary study endpoint, including 61 deaths and 116 hospitalizations for heart failure. After adjustment for age, gender, New York Heart Association class, atrial fibrillation history, creatinine, sodium, BNP, ejection fraction, and right ventricular fractional shortening, only E/e' remained as a predictor, with a hazard ratio = 1.49 and P = 0.0012.

CONCLUSION

The incidence of hospitalizations for HF and deaths in KaRen was high and E/e' predicted adverse clinical outcomes. These observations should help in the risk stratification and therapy of HFpEF.

Left atrial function in heart failure with impaired and preserved ejection fraction

PURPOSE OF REVIEW

Left atrial structural and functional changes in heart failure are relatively ignored parts of cardiac assessment. This review illustrates the pathophysiological and functional changes in left atrium in heart failure as well as their prognostic value.

RECENT FINDINGS

Heart failure can be divided into those with systolic dysfunction and heart failure with preserved ejection fraction (HFPEF). Left atrial enlargement and dysfunction commonly occur in systolic heart failure, in particular, in idiopathic dilated cardiomyopathy. Atrial enlargement and dysfunction also carry important prognostic value in systolic heart failure, independently of known parameters such as left ventricular ejection fraction. In HFPEF, there is evidence of left atrial enlargement, impaired atrial compliance, and reduction of atrial pump function. This occurs not only at rest but also during exercise, indicating significant impairment of atrial contractile reserve. Furthermore, atrial dyssynchrony is common in HFPEF. These factors further contribute to the development of new onset or progression of atrial arrhythmias, in particular, atrial fibrillation.

SUMMARY

Left atrial function is an integral part of cardiac function and its structural and functional changes in heart failure are common. As changes of left atrial structure and function have different clinical implications in systolic heart failure and HFPEF, routine assessment is warranted.

Heart failure with preserved ejection fraction in the elderly: scope of the problem

Heart failure with preserved ejection fraction (HFpEF) is the most common form of heart failure (HF) in older adults, particularly women, and is increasing in prevalence as the population ages. With morbidity and mortality on par with HF with reduced ejection fraction, it remains a most challenging clinical syndrome for the practicing clinician and basic research scientist. Originally considered to be predominantly caused by diastolic dysfunction, more recent insights indicate that HFpEF in older persons is typified by a broad range of cardiac and non-cardiac abnormalities and reduced reserve capacity in multiple organ systems. The globally reduced reserve capacity is driven by: 1) inherent age-related changes; 2) multiple, concomitant co-morbidities; 3) HFpEF itself, which is likely a systemic disorder. These insights help explain why: 1) co-morbidities are among the strongest predictors of outcomes; 2) approximately 50% of clinical events in HFpEF patients are non-cardiovascular; 3) clinical drug trials in HFpEF have been negative on their primary outcomes. Embracing HFpEF as a true geriatric syndrome, with complex, multi-factorial pathophysiology and clinical heterogeneity could provide new mechanistic insights and opportunities for progress in management. This article is part of a Special Issue entitled CV Aging.

The ratio of early transmitral flow velocity (E) to early mitral annular velocity (Em) predicts improvement in left ventricular systolic and diastolic function 1 year after catheter ablation for atrial fibrillation

AIMS

Successful rhythm control after atrial fibrillation catheter ablation is known to induce left atrial reverse remodelling and improve left ventricular (LV) function. We explored the clinical factors affecting LV systolic and diastolic function 1-year after catheter ablation for atrial fibrillation.

METHODS AND RESULTS

We compared pre-procedural and 1-year follow-up echocardiograms in 521 patients with atrial fibrillation who underwent catheter ablation. Left ventricular systolic function was estimated by the ejection fraction (EF); diastolic function was estimated by the ratio of early transmitral flow velocity (E) to early mitral annular velocity (Em). (i) Catheter ablation of atrial fibrillation significantly reduced left atrium volume index (P < 0.001) and improved LV EF both in patients with recurrent atrial fibrillation (n = 133, P = 0.008) and those without recurrence (n = 388, P < 0.001). (ii) Follow-up EF was significantly improved in patients with baseline E/Em < 15 (n = 454, P < 0.001), whereas E/Em was significantly reduced in patients with pre-procedural E/Em ≥ 15 (n = 67, P = 0.008). (iii) Baseline E/Em < 15 (β = -3.854, 95% CI -5.99 to -1.72, P < 0.001), baseline EF <50% (β = 10.586, 95% CI 7.55 to 13.63, P < 0.001), and female (β = -1.726, 95% CI -3.36 to -0.10, P = 0.038) were independently associated with improved EF. Baseline E/Em ≥ 15 (β = 4.896, 95% CI 3.45 to 6.34, P < 0.001) and younger age (β = -0.066, 95% CI -0.11 to -0.02, P = 0.003) were independent factors associated with improved E/Em.

CONCLUSION

Pre-procedural E/Em predicted improvement in LV systolic and diastolic functions 1 year after catheter ablation for atrial fibrillation. Low baseline E/Em was independently associated with improved EF, while high E/Em predicted improvement in LV diastolic function.

Mechanical abnormalities detected with conventional echocardiography are associated with response and midterm survival in CRT

OBJECTIVES

Our aim was to identify "correctable abnormalities" using conventional grayscale and blood-pool Doppler echocardiography and evaluate their ability to predict both response and midterm survival.

BACKGROUND

Identification of mechanical abnormalities that may be corrected with cardiac resynchronization therapy (CRT) is useful for predicting echocardiographic response at 1-year follow-up.

METHODS

A total of 200 CRT patients were included. Clinical evaluation and echocardiography were performed before and after CRT to assess the presence of the mechanical abnormalities of interest (septal flash, abnormal ventricular filling, or exaggerated interventricular dependence). Response to CRT was defined as a reduction in left ventricular (LV) end-systolic volume (ESV) ≥15%. Four subgroups of extent of response were defined: LVESV reduction >26.68% (extensive remodeling); LVESV reduction 6.8% to 26.68% (slight remodeling); LVESV reduction <6.8% (no remodeling) and clinical response; and LVESV reduction <6.8% without clinical response or the occurrence of death or heart transplantation. Midterm cardiovascular survival was evaluated (mean follow-up 38 ± 19 months).

RESULTS

The presence of a correctable abnormality was independently associated with a better rate (odds ratio: 0.03 [95% confidence interval (CI): 0.01 to 0.10], p < 0.001) and extent of response to CRT (n = 59 [96.7%] for the extensive remodeling subgroup vs. n = 53 [85.5%] for the slight remodeling subgroup vs. n = 19 [47.5%] for the no remodeling with clinical response subgroup vs. n = 17 [45.9%] for the no remodeling without clinical response subgroup, p = 0.0001), as well as with increased midterm survival (hazard ratio: 0.11 [95% CI: 0.2 to 0.6]). Other independent predictors included creatinine level and LV end-systolic diameter for response; New York Heart Association functional class IV, creatinine, LV end-systolic diameter, and transmurality index for extent of response; and New York Heart Association functional class IV for cardiovascular mortality.

CONCLUSIONS

The presence of a correctable abnormality evaluated by conventional echocardiography is associated with LV reverse remodeling and better survival at midterm follow-up. Clinical characteristics and myocardial viability also have an influence.

Left Atrium: Still a Neglected Chamber?

It is widely recognized that an effective cardiovascular system is based upon both a good ventricular-vascular interplay and a good ventricular-atrial interaction in all the phases of cardiac cycle. Moreover, left atrial dysfunction has been identified to be contributory in several common cardiovascular conditions, such as heart failure, atrial fibrillation and valvular heart disease; for instance, a good anatomical and functional assessment of this cardiac chamber is mandatory. For this purpose a multimodality imaging approach – including two-dimensional and three-dimensional echocardiography, speckle tracking technique, cardiac computed tomography (CT) and cardiac magnetic resonance (CMR) – is the most suitable one to achieve the best functional and anatomical evaluation of this cardiac chamber.

Baseline characteristics of patients with heart failure and preserved ejection fraction included in the Karolinska Rennes (KaRen) study

BACKGROUND

Karolinska Rennes (KaRen) is a prospective observational study to characterize heart failure patients with preserved ejection fraction (HFpEF) and to identify prognostic factors for long-term mortality and morbidity.

AIMS

To report characteristics and echocardiography at entry and after 4-8 weeks of follow-up.

METHODS

Patients were included following an acute heart failure presentation with B-type natriuretic peptide (BNP)>100 ng/L or N-terminal pro-BNP (NT-proBNP)>300 ng/L and left ventricular ejection fraction (LVEF)>45%.

RESULTS

The mean ± SD age of 539 included patients was 77 ± 9 years and 56% were women. Patient history included hypertension (78%), atrial tachyarrhythmia (44%), prior heart failure (40%) and anemia (37%), but left bundle branch block was rare (3.8%). Median NT-proBNP was 2448 ng/L (n=438), and median BNP 429 ng/L (n=101). Overall, 101 patients did not return for the follow-up visit, including 13 patients who died (2.4%). Apart from older age (80 ± 9 vs. 76 ± 9 years; P=0.006), there were no significant differences in baseline characteristics between patients who did and did not return for follow-up. Mean LVEF was lower at entry than follow-up (56% vs. 62%; P<0.001). At follow-up, mean E/e' was 12.9 ± 6.1, left atrial volume index 49.4±17.8mL/m(2). Mean global left ventricular longitudinal strain was -14.6 ± 3.9%; LV mass index was 126.6 ± 36.2g/m(2).

CONCLUSIONS

Patients in KaRen were old with slight female dominance and hypertension as the most prevalent etiological factor. LVEF was preserved, but with increased LV mass and depressed LV diastolic and longitudinal systolic functions. Few patients had signs of electrical dyssynchrony (ClinicalTrials.gov.- NCT00774709).

Heart failure highlights in 2012-2013

Heart failure has become the cardiovascular epidemic of the century. The European Journal of Heart Failure is dedicated to the advancement of knowledge in the field of heart failure management. In 2012 and 2013, several pioneering scientific discoveries and paradigm-shifting clinical trials have been published. In the current paper, we will discuss the most significant novel insights into the pathophysiology, diagnosis, and treatment of heart failure that were published during this period. All relevant research areas are discussed, including pathophysiology, co-morbidities, arrhythmias, biomarkers, clinical trials, and device therapy, including left ventricular assist devices.

Pre-clinical diastolic dysfunction

Pre-clinical diastolic dysfunction (PDD) has been broadly defined as left ventricular diastolic dysfunction without the diagnosis of congestive heart failure (HF) and with normal systolic function. PDD is an entity that remains poorly understood, yet has definite clinical significance. Although few original studies have focused on PDD, it has been shown that PDD is prevalent, and that there is a clear progression from PDD to symptomatic HF including dyspnea, edema, and fatigue. In diabetic patients and in patients with coronary artery disease or hypertension, it has been shown that patients with PDD have a significantly higher risk of progression to heart failure and death compared with patients without PDD. Because of these findings and the increasing prevalence of the heart failure epidemic, it is clear that an understanding of PDD is essential to decreasing patients' morbidity and mortality. This review will focus on what is known concerning pre-clinical diastolic dysfunction, including definitions, staging, epidemiology, pathophysiology, and the natural history of the disease. In addition, given the paucity of trials focused on PDD treatment, studies targeting risk factors associated with the development of PDD and therapeutic trials for heart failure with preserved ejection fraction will be reviewed.