A systematic review of diastolic stress tests in heart failure with preserved ejection fraction, with proposals from the EU-FP7 MEDIA study group

The assessment of left ventricular diastolic function: guidance and recommendations from the British Society of Echocardiography

Impairment of left ventricular (LV) diastolic function is common amongst those with left heart disease and is associated with significant morbidity. Given that, in simple terms, the ventricle can only eject the volume with which it fills and that approximately one half of hospitalisations for heart failure (HF) are in those with normal/'preserved' left ventricular ejection fraction (HFpEF) (Bianco et al. in JACC Cardiovasc Imaging. 13:258-271, 2020. 10.1016/j.jcmg.2018.12.035), where abnormalities of ventricular filling are the cause of symptoms, it is clear that the assessment of left ventricular diastolic function (LVDF) is crucial for understanding global cardiac function and for identifying the wider effects of disease processes. Invasive methods of measuring LV relaxation and filling pressures are considered the gold-standard for investigating diastolic function. However, the high temporal resolution of trans-thoracic echocardiography (TTE) with widely validated and reproducible measures available at the patient's bedside and without the need for invasive procedures involving ionising radiation have established echocardiography as the primary imaging modality. The comprehensive assessment of LVDF is therefore a fundamental element of the standard TTE (Robinson et al. in Echo Res Pract7:G59-G93, 2020. 10.1530/ERP-20-0026). However, the echocardiographic assessment of diastolic function is complex. In the broadest and most basic terms, ventricular diastole comprises an early filling phase when blood is drawn, by suction, into the ventricle as it rapidly recoils and lengthens following the preceding systolic contraction and shortening. This is followed in late diastole by distension of the compliant LV when atrial contraction actively contributes to ventricular filling. When LVDF is normal, ventricular filling is achieved at low pressure both at rest and during exertion. However, this basic description merely summarises the complex physiology that enables the diastolic process and defines it according to the mechanical method by which the ventricles fill, overlooking the myocardial function, properties of chamber compliance and pressure differentials that determine the capacity for LV filling. Unlike ventricular systolic function where single parameters are utilised to define myocardial performance (LV ejection fraction (LVEF) and Global Longitudinal Strain (GLS)), the assessment of diastolic function relies on the interpretation of multiple myocardial and blood-flow velocity parameters, along with left atrial (LA) size and function, in order to diagnose the presence and degree of impairment. The echocardiographic assessment of diastolic function is therefore multifaceted and complex, requiring an algorithmic approach that incorporates parameters of myocardial relaxation/recoil, chamber compliance and function under variable loading conditions and the intra-cavity pressures under which these processes occur. This guideline outlines a structured approach to the assessment of diastolic function and includes recommendations for the assessment of LV relaxation and filling pressures. Non-routine echocardiographic measures are described alongside guidance for application in specific circumstances. Provocative methods for revealing increased filling pressure on exertion are described and novel and emerging modalities considered. For rapid access to the core recommendations of the diastolic guideline, a quick-reference guide (additional file 1) accompanies the main guideline document. This describes in very brief detail the diastolic investigation in each patient group and includes all algorithms and core reference tables.

Prediction of symptom development and aortic valve replacement in patients with low-gradient severe aortic stenosis

Aims

Current evidence on the prognostic value of exercise stress echocardiography (ESE) in asymptomatic patients with low-gradient severe aortic stenosis (AS) is limited. Therefore, this study aimed to elucidate its prognostic implications for patients with low-gradient severe AS and determine the added value of ESE in risk stratification for this population.

Methods and results

This retrospective observational study included 122 consecutive asymptomatic patients with either moderate [mean pressure gradient (MPG) < 40 mmHg and aortic valve area (AVA) 1.0-1.5 cm2] or low-gradient severe (MPG < 40 mmHg and AVA < 1.0 cm2) AS and preserved left ventricular ejection fraction (≥50%) who underwent ESE. All patients were followed up for AS-related events. Of 143 patients, 21 who met any exclusion criteria, including early interventions, were excluded, and 122 conservatively managed patients [76.5 (71.0-80.3) years; 48.3% male] were included in this study. During a median follow-up period of 989 (578-1571) days, 64 patients experienced AS-related events. Patients with low-gradient severe AS had significantly lower event-free survival rates than those with moderate AS (log-rank test, P < 0.001). Multivariable Cox regression analysis showed that the mitral E/e' ratio during exercise was independently associated with AS-related events (hazard ratio = 1.075, P < 0.001) in patients with low-gradient severe AS.

Conclusion

This study suggests that asymptomatic patients with low-gradient severe AS have worse prognoses than those with moderate AS. Additionally, the mitral E/e' ratio during exercise is a useful parameter for risk stratification in patients with low-gradient severe AS.

Rest and exercise-stress estimated pulmonary capillary wedge pressure using real-time free-breathing cardiovascular magnetic resonance imaging

BACKGROUND

Identification of increased pulmonary capillary wedge pressure (PCWP) by right heart catheterization (RHC) is the reference standard for the diagnosis of heart failure with preserved ejection fraction (HFpEF). Recently, cardiovascular magnetic resonance (CMR) imaging estimation of PCWP at rest was introduced as a non-invasive alternative. Since many patients are only identified during physiological exercise-stress, we hypothesized that novel exercise-stress CMR-derived PCWP emerges superior compared to its assessment at rest.

METHODS

The HFpEF-Stress Trial prospectively recruited 75 patients with exertional dyspnea and diastolic dysfunction who then underwent rest and exercise-stress RHC and CMR. HFpEF was defined according to PCWP (overt HFpEF ≥15 mmHg at rest, masked HFpEF ≥25 mmHg during exercise-stress). CMR-derived PCWP was calculated based on previously published formula using left ventricular mass and either biplane left atrial volume (LAV) or monoplane left atrial area (LAA).

RESULTS

LAV (rest/stress: r = 0.50/r = 0.55, p < 0.001) and LAA PCWP (rest/stress: r = 0.50/r = 0.48, p < 0.001) correlated significantly with RHC-derived PCWP while numerically overestimating PCWP at rest and underestimating PCWP during exercise-stress. LAV and LAA PCWP showed good diagnostic accuracy to detect HFpEF (area under the receiver operating characteristic curve (AUC) LAV rest 0.73, stress 0.81; LAA rest 0.72, stress 0.77) with incremental diagnostic value for the detection of masked HFpEF using exercise-stress (AUC LAV rest 0.54 vs stress 0.67, p = 0.019, LAA rest 0.52 vs stress 0.66, p = 0.012). LAV but not LAA PCWP during exercise-stress was a predictor for 24 months hospitalization independent of a medical history for atrial fibrillation (hazard ratio (HR) 1.26, 95% confidence interval 1.02-1.55, p = 0.032).

CONCLUSION

Non-invasive PCWP correlates well with the invasive reference at rest and during exercise stress. There is overall good diagnostic accuracy for HFpEF assessment using CMR-derived estimated PCWP despite deviations in absolute agreement. Non-invasive exercise derived PCWP may particularly facilitate detection of masked HFpEF in the future.

Pathophysiologic and prognostic importance of cardiac power output reserve in heart failure with preserved ejection fraction

AIMS

Heart failure with preserved ejection fraction (HFpEF) is a syndrome characterized by multiple cardiac reserve limitations during exercise. Cardiac power output (CPO) is an index of global cardiac performance and can be estimated non-invasively by echocardiography. We hypothesized that CPO reserve during exercise would be associated with impaired cardiovascular reserve, exercise intolerance, and adverse outcomes in HFpEF.

METHODS AND RESULTS

Exercise stress echocardiography was performed in 425 dyspnoeic patients [217 HFpEF and 208 non-heart failure (HF) controls] to estimate CPO at rest and during exercise. We classified patients with HFpEF based on the median value of changes in CPO from rest to peak exercise (ΔCPO >0.49 W/100 g). Patients with HFpEF and a lower CPO reserve had poorer biventricular systolic function, impaired chronotropic response during exercise, and worse aerobic capacity than controls and those with a higher CPO reserve. During a median follow-up of 358 days, a composite outcome of all-cause mortality or HF events occurred in 30 patients. Patients with a lower CPO reserve had four-fold and nearly 10-fold increased risks of the outcomes compared with those with a higher CPO reserve and controls, respectively [hazard ratio (HR) 4.05, 95% confidence interval (CI) 1.16-10.1, P = 0.003 and HR 9.61, 95% CI 3.58-25.8, P < 0.0001]. We further found that a lower CPO reserve had an incremental prognostic value over the H2FPEF score and exercise duration. In contrast, resting CPO did not predict clinical outcomes in patients with HFpEF.

CONCLUSION

A lower CPO reserve was associated with biventricular systolic dysfunction, chronotropic incompetence, exercise intolerance, and adverse outcomes in patients with HFpEF.

Echocardiographic evaluation of cardiac reserve to detect subtle cardiac dysfunction in mice

AIMS

Cardiac reserve is a sensitive tool for early detection of cardiac dysfunction. However, cardiac reserve assessment by catecholamine stress echocardiography in mice varied in the doses of β-adrenergic agonists and the time point for measurements, which may lead to inaccurate readouts. This study aims to establish a standardized protocol for assessing cardiac reserve in mice.

MAIN METHODS

C57BL/6J mice under isoflurane anesthesia were intraperitoneally injected with varying doses of isoproterenol (Iso), and subjected to echocardiographic measurements.

KEY FINDINGS

Heart rate (HR), ejection fraction (EF), fractional shortening (FS), global longitudinal strain (GLS) and strain rate all reached peak values within 1-3 min after Iso injection at doses higher than 0.2 mg/kg. Compared with 0.1 mg/kg Iso, 0.2 mg/kg Iso resulted in higher HR, EF, FS and GLS, whereas doses higher than 0.2 mg/kg did not yield further increase. Cardiac response of female mice recapitulated main characteristics of those of male mice except that female mice displayed higher maximum HR and were more sensitive to higher doses of Iso. Furthermore, the advantages of present stress protocol over conventional baseline echocardiographic measurements were verified in comparisons of exercised vs. sedentary and aged vs. young mice for cardiac function evaluation.

SIGNIFICANCE

We developed a reproducible and sensitive approach to evaluate cardiac reserve by continuously monitoring cardiac function every minute for 3 min after 0.2 mg/kg Iso injection. This approach will enable detection of subtle cardiac dysfunction and accelerate innovative research in cardiac pathophysiology.

The Role of Echocardiography in Evaluating Cardiovascular Diseases in Patients with Diabetes Mellitus

Patients with diabetes mellitus are highly susceptible to cardiovascular complications, which are directly correlated with cardiovascular morbidity and mortality. In addition to coronary artery disease, there is growing awareness of the risk and prevalence of heart failure (HF) in patients with diabetes. Echocardiography is an essential diagnostic modality commonly performed in patients with symptoms suggestive of cardiovascular diseases (CVD), such as dyspnea or chest pain, to establish or rule out the cause of symptoms. Conventional echocardiographic parameters, such as left ventricular ejection fraction, are helpful not only for diagnosing CVD but also for determining severity, treatment strategy, prognosis, and response to treatment. Echocardiographic myocardial strain, a novel echocardiographic technique, enables the detection of early changes in ventricular dysfunction before HF symptoms develop. This article aims to review the role of echocardiography in evaluating CVD in patients with diabetes mellitus and how to use it in patients with suspected cardiac diseases.

Role of Exercise Stress Echocardiography in Pulmonary Hypertension

Resting and exercise right heart catheterisation is the gold standard method to diagnose and differentiate types of pulmonary hypertension (PH). As it carries technical challenges, the question arises if non-invasive exercise stress echocardiography may be used as an alternative. Exercise echocardiography can unmask exercise PH, detect the early stages of left ventricular diastolic dysfunction, and, therefore, differentiate between pre- and post-capillary PH. Regardless of the underlying aetiology, a developed PH is associated with increased mortality. Parameters of overt right ventricle (RV) dysfunction, including RV dilation, reduced RV ejection fraction, and elevated right-sided filling pressures, are detectable with resting echocardiography and are associated with worse outcome. However, these measures all fail to identify occult RV dysfunction. Echocardiographic measures of RV contractile reserve during exercise echocardiography are very promising and provide incremental prognostic information on clinical outcome. In this paper, we review pulmonary haemodynamic response to exercise, briefly describe the modalities for assessing pulmonary haemodynamics, and discuss in depth the contemporary key clinical application of exercise stress echocardiography in patients with PH.

Utility of E/e' Ratio During Low-Level Exercise to Diagnose Heart Failure With Preserved Ejection Fraction

BACKGROUND

E/e' ratio during exercise is the key parameter in identifying elevated pulmonary capillary wedge pressure (PCWP), and thus heart failure with preserved ejection fraction (HFpEF). However, its diagnostic value is limited when mitral inflow or tissue velocities are fused during elevated heart rate.

OBJECTIVES

The authors hypothesized that E/e' ratio during low-level (20 W) exercise (E/e'20W) can help diagnose HFpEF.

METHODS

Ergometric exercise stress echocardiography was performed in 215 dyspneic patients with an EF ≥50%. The authors determined the feasibility of E/e' ratio at each stage (frequency of patients who had measurable E/e' without E-A fusion among 215 participants) and examined whether E/e'20W could predict normal E/e' ratio during peak exercise (E/e'peak ≤15). The authors also evaluated whether E/e'20W could predict normal PCWP during exercise (PCWP <25 mm Hg) in a subset of participants (n = 45) who underwent exercise right heart catheterization.

RESULTS

The feasibility of the E/e' ratio decreased from 100% at rest to 96.3% during 20-W exercise and 74.9% during peak exercise caused by E-A fusion. In patients with E/e'peak >15, there was an increase in E/e' ratio from rest to 20-W exercise (11.2 ± 2.1 to 16.3 ± 3.5; P < 0.0001), but it did not change significantly from 20-W exercise to peak exercise (P = 0.12). E/e'20W predicted E/e'peak ≤15 (AUC: 0.91; P < 0.0001) with the cutoff value of ≤12.4 showing high specificity (94%) and positive predictive value (98%). During 20-W exercise, 93% of the HFpEF patients developed PCWP ≥25 mm Hg. E/e'20W predicted normal PCWP during exercise (AUC: 0.77; P = 0.01) with the cutoff value of ≤12.4 showing high specificity (83%).

CONCLUSIONS

E/e' ratio during low-level exercise is highly feasible and predicts normal E/e' ratio or PCWP during peak exercise with high specificity. These data suggest that E/e'20W could be used as an alternative to the peak exercise value to rule out HFpEF in patients with dyspnea.

Contractile Reserve in Heart Failure with Preserved Ejection Fraction

Background: Diastolic stress echocardiography (SE) is useful for confirming the diagnosis of heart failure with preserved left ventricular ejection fraction (HFpEF) when it is uncertain. The aim of this study was to assess the value of new echocardiographic parameters during diastolic SE in patients with dyspnea and suspected HFpEF. Methods: Sixty-two patients with exertional dyspnea and inconclusive rest echocardiography for a diagnosis of HFpEF were enrolled. Exercise SE was performed in all patients. Contractile reserve (LVCR) was assessed by measuring: 1. changes in the left ventricular ejection fraction (LVEF) between rest and peak stress; 2. stress-to-rest ratio of force (force was defined as the ratio between systolic arterial pressure and left ventricular end-systolic volume); and 3. mechanical reserve, defined as the change in systolic strain (GLS) between rest and peak stress. Results: Diagnosis of HFpEF was performed by SE in 26 patients. Comparing patients with a diagnosis of HFpEF (group A) to patients with other causes of dyspnea (group B), we found a significant increase in the E/e’ ratio in group A at peak stress. LV GLS was significantly reduced in group A compared to group B at rest and stress (p value 0.01 at rest; p value 0.04 at stress). At peak stress, GLS did not significantly increase in group A, while it increased in group B (p value 0.04). LVEF increased significantly in both groups. Conclusion: Patients with HFpEF have impaired LVCR when assessed using GLS. Thus, the assessment of mechanical reserve could give additional diagnostic information during stress tests in patients with HFpEF.

2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure" replaces the "2013 ACCF/AHA Guideline for the Management of Heart Failure" and the "2017 ACC/AHA/HFSA Focused Update of the 2013 ACCF/AHA Guideline for the Management of Heart Failure." The 2022 guideline is intended to provide patient-centric recommendations for clinicians to prevent, diagnose, and manage patients with heart failure.

METHODS

A comprehensive literature search was conducted from May 2020 to December 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (PubMed), EMBASE, the Cochrane Collaboration, the Agency for Healthcare Research and Quality, and other relevant databases. Additional relevant clinical trials and research studies, published through September 2021, were also considered. This guideline was harmonized with other American Heart Association/American College of Cardiology guidelines published through December 2021. Structure: Heart failure remains a leading cause of morbidity and mortality globally. The 2022 heart failure guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with heart failure, with the intent to improve quality of care and align with patients' interests. Many recommendations from the earlier heart failure guidelines have been updated with new evidence, and new recommendations have been created when supported by published data. Value statements are provided for certain treatments with high-quality published economic analyses.

Peak atrio-ventricular mechanics predicts exercise tolerance in heart failure patients

PURPOSE

Exercise intolerance is a cardinal symptom of patients with heart failure (HF). We hypothesized that patients with HF with preserved ejection fraction (HFpEF) in comparison with those with reduced ejection fraction (HFrEF) have disproportionate exercise-induced impairment of left atrial (LA) function that may explain the effort intolerance.

METHODS

Total 40 HFpEF patients, 40 HFrEF patients, and 20 matched healthy controls underwent resting and exercise stress transthoracic echocardiography using modified Bruce protocol with speckle-tracking derived assessments of peak atrial longitudinal strain (PALS) and left ventricular global longitudinal strain (LVGLS).

RESULTS

In comparison to controls, PALS and LVGLS were reduced in HFpEF and HFrEF patients (P < 0.01); however, the strain magnitudes were significantly lower in HFrEF than in HFpEF (P < 0.01). Both HFpEF and HFrEF showed a 28% and 30% reduction in exercise time in comparison with controls (HFpEF, 363 ± 152, HFrEF 352 ± 91, controls, 505 ± 42 s, P < 0.01) and exercise-related rise in E/E' in HFpEF patients. However, during exercise PALS reduced from resting values by 26% (resting 23.1 ± 4.7 and peak 18.5 ± 3.5, P < 0.01) in HFpEF but only 8% in HFrEF (resting 11.5 ± 1.4 and peak 10.5 ± 1.5, P < 0.01), and remained unchanged in controls (resting 34 ± 1.9 and peak 34.4 ± 1.2, P = 0.4). Regression analysis of the combined data from the HF patients and controls revealed that PALS was independently associated with exercise time such that a 1% reduction in PALS was associated with a 10 s reduction in exercise duration (p < 0.01). PALS at baseline and peak exercise differentiated normal from HF patients. LVGLS at baseline and peak exercise differentiated HFpEF from HFrEF and patients of HFpEF showed abnormality of both PALS and LVGLS.

CONCLUSION

Although left ventricle and LA strain are lower in HFrEF than HFpEF at rest and exercise compared to healthy controls, patients with HFpEF show more profound deterioration of LA reservoir function with exercise which appears to contribute to exercise intolerance.

2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure

AIM

The "2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure" replaces the "2013 ACCF/AHA Guideline for the Management of Heart Failure" and the "2017 ACC/AHA/HFSA Focused Update of the 2013 ACCF/AHA Guideline for the Management of Heart Failure." The 2022 guideline is intended to provide patient-centric recommendations for clinicians to prevent, diagnose, and manage patients with heart failure.

METHODS

A comprehensive literature search was conducted from May 2020 to December 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (PubMed), EMBASE, the Cochrane Collaboration, the Agency for Healthcare Research and Quality, and other relevant databases. Additional relevant clinical trials and research studies, published through September 2021, were also considered. This guideline was harmonized with other American Heart Association/American College of Cardiology guidelines published through December 2021.

STRUCTURE

Heart failure remains a leading cause of morbidity and mortality globally. The 2022 heart failure guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with heart failure, with the intent to improve quality of care and align with patients' interests. Many recommendations from the earlier heart failure guidelines have been updated with new evidence, and new recommendations have been created when supported by published data. Value statements are provided for certain treatments with high-quality published economic analyses.

Exercise Stress Echocardiography in the Diagnostic Evaluation of Heart Failure with Preserved Ejection Fraction

More than half of patients with heart failure have a preserved ejection fraction (HFpEF). The prevalence of HFpEF has been increasing worldwide and is expected to increase further, making it an important health-care problem. The diagnosis of HFpEF is straightforward in the presence of obvious objective signs of congestion; however, it is challenging in patients presenting with a low degree of congestion because abnormal elevation in intracardiac pressures may occur only during physiological stress conditions, such as during exercise. On the basis of this hemodynamic background, current consensus guidelines have emphasized the importance of exercise stress testing to reveal abnormalities during exercise, and exercise stress echocardiography (i.e., diastolic stress echocardiography) may be used as an initial diagnostic approach to HFpEF owing to its noninvasive nature and wide availability. However, evidence supporting the use of this method remains limited and many knowledge gaps exist with respect to diastolic stress echocardiography. This review summarizes the current understanding of the use of diastolic stress echocardiography in the diagnostic evaluation of HFpEF and discusses its strengths and limitations to encourage future studies on this subject.

Echocardiography in the diagnostic evaluation and phenotyping of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) represents one of the greatest unmet needs in modern cardiology given its diagnostic difficulty and limited therapeutic options. Echocardiography provides valuable information on cardiac structure, function, and hemodynamics and plays a central role in the evaluation of HFpEF. Echocardiography is crucial in identifying HFpEF among patients with dyspnea, especially when overt congestion is absent. The combination of echocardiographic indices of diastolic function, clinical characteristics, and natriuretic peptide tests has been proposed in the diagnostic evaluation of patients with suspected HFpEF. Echocardiography also provides valuable insight into the pathophysiology and underlying phenotypes of HFpEF. Exercise stress echocardiography can also detect abnormalities that develop only during exercise. This may enhance the diagnosis of HFpEF by demonstrating elevation in the left ventricular filling pressure and may have potential for better pathophysiological characterization. This review focuses on the role of echocardiography in the diagnostic evaluation and phenotyping of HFpEF. We also discuss the potential role of exercise stress echocardiography for the diagnosis and disease phenotyping of HFpEF.

Exercise-induced B-lines in heart failure with preserved ejection fraction occur along with diastolic function worsening

Aims

Pulmonary congestion during exercise assessed by lung ultrasound predicts negative outcome in patients with heart failure with preserved ejection fraction (HFpEF). We aimed at assessing predictors of exercise‐induced pulmonary B‐lines in HFpEF patients.

Methods and results

Eighty‐one I–II NYHA class HFpEF patients (65.0  ± 8.2 y/o, 56.8% females) underwent standard and strain echocardiography, lung ultrasound, and natriuretic peptide assessment during supine exercise echocardiography (baseline and peak exercise). Peak values and their changes were compared in subgroups according to exercise lung congestion grading (peak B‐lines >10 or ≤10). Exercise elicited significant changes for all echocardiographic parameters in both subgroups [39/81 (48.1%) with peak B‐lines >10; 42/81 (51.9%) with B‐lines ≤10]. Peak values and changes of E‐wave (and its derived indices) were significantly higher in patients with >10 peak B‐lines compared with those with ≤10 B‐line (all P‐values <0.03), showing significant correlation with peak B‐lines for all parameters; concomitantly, global longitudinal strain (GLS) and global strain rate (GSR) during systole (GSRs), early (GSRe) and late (GSRa) diastole, and isovolumic relaxation (GSRivr) were reduced in patients with B‐lines >10 (all P‐values <0.05), showing a negative correlation with peak B‐lines. By adjusted linear regression analysis, peak and change diastolic parameters (E‐wave, E/e′, GSRivr, and E/GSRivr) and peak GLS were individually significantly associated with peak B‐lines. By covariate‐adjusted multivariable model, E/e′ and GSRa at peak exercise were retained as independent predictors of peak B‐lines, with substantial goodness of fit of model (adjusted R² 0.776).

Conclusions

In HFpEF, development of pulmonary congestion upon exercise is mostly concomitant with exercise‐induced worsening of diastolic function.

Advanced Heart Failure in a Special Population: Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a complex clinical syndrome that has become a global health issue, with mortality ranging from 53% to 74% at 5 years. It is defined as the presence of signs and symptoms of heart failure associated with left ventricular ejection fraction greater than or equal to 50%. The definition and diagnosis of HFpEF in patients with unexplained dyspnea remain a clinical challenge in the absence of a unique diagnostic algorithm universally recognized. Clinical trials conducted so far did not show a significant improvement of prognosis, but forthcoming therapies could provide innovative solutions.

Left atrial conduit flow rate at baseline and during exercise: an index of impaired relaxation in HFpEF patients

Aims

In healthy subjects, adrenergic stimulation augments left ventricular (LV) long‐axis shortening and lengthening, and increases left atrial (LA) to LV intracavitary pressure gradients in early diastole. Lower increments are observed in patients with heart failure with preserved ejection fraction (HFpEF). We hypothesized that exercise in HFpEF would further impair passive LV filling in early‐mid diastole, during conduit flow from pulmonary veins.

Methods and results

Twenty HFpEF patients (67.8 ± 9.8 years; 11 women), diagnosed using 2007 ESC recommendations, underwent ramped semi‐supine bicycle exercise to submaximal target heart rate (∼100 bpm) or symptoms. Seventeen asymptomatic subjects (64.3 ± 8.9 years; 7 women) were controls. Simultaneous LA and LV volumes were measured from pyramidal 3D‐echocardiographic full‐volume datasets acquired from an apical window at baseline and during stress, together with brachial arterial pressure. LA conduit flow was computed from the increase in LV volume from its minimum at end‐systole to the last frame before atrial contraction (onset of the P wave), minus the reduction in LA volume during the same time interval; the difference was integrated and expressed as average flow rate, according to a published formula. The slope of single‐beat preload recruitable stroke work (PRSW) quantified LV inotropic state. 3D LV torsion (rotation of the apex minus rotation of the base divided by LV length) was also measurable, both at rest and during stress, in 10 HFpEF patients and 4 controls. There were divergent responses in conduit flow rate, which increased by 40% during exercise in controls (+17.8 ± 37.3 mL/s) but decreased by 18% in patients with HFpEF (−9.6 ± 42.3 mL/s) (P = 0.046), along with congruent changes (+1.77 ± 1.13°/cm vs. −1.94 ± 2.73°/cm) in apical torsion (P = 0.032). Increments of conduit flow rate and apical torsion during stress correlated with changes in PRSW slope (P = 0.003 and P = 0.006, respectively).

Conclusions

In HFpEF, conduit flow rate decreases when diastolic dysfunction develops during exercise, in parallel with changes in LV inotropic state and torsion, contributing to impaired stroke volume reserve. Conduit flow is measurable using 3D‐echocardiographic full‐volume atrio‐ventricular datasets, and as a marker of LV relaxation can contribute to the diagnosis of HFpEF.

The Heart Failure with Preserved Ejection Fraction Conundrum-Redefining the Problem and Finding Common Ground?

PURPOSE OF REVIEW

Heart failure with preserved ejection fraction (HFpEF) or diastolic heart failure (DHF) makes up more than half of all congestive heart failure presentations (CHF). With an ageing population, the case load and the financial burden is projected to increase, even to epidemic proportions. CHF hospitalizations add too much of the financial and infrastructure strain. Unlike systolic heart failure (SHF), much is still either uncertain or unknown. Specifically, in epidemiology, the disease burden is established; however, risk factors and pathophysiological associations are less clear; diagnostic tools are based on rigid parameters without the ability to accurately monitor treatments effects and disease progression; finally, therapeutics are similar to SHF but without prognostic data for efficacy.

RECENT FINDINGS

The last several years have seen guidelines changing to account for greater epidemiological observations. Most of these remain general observation of shortness of breath symptom matched to static echocardiographic parameters. The introduction of exercise diastolic stress test has been welcome and warrants greater focus. HFpEF is likely to see new thinking in the coming decades. This review provides some of perspective on this topic.

Machine learning: at the heart of failure diagnosis

PURPOSE OF REVIEW

Refinement in machine learning (ML) techniques and approaches has rapidly expanded artificial intelligence applications for the diagnosis and classification of heart failure (HF). This review is designed to provide the clinician with the basics of ML, as well as this technologies future utility in HF diagnosis and the potential impact on patient outcomes.

RECENT FINDINGS

Recent studies applying ML methods to unique data sets available from electrocardiography, vectorcardiography, echocardiography, and electronic health records show significant promise for improving diagnosis, enhancing detection, and advancing treatment of HF. Innovations in both supervised and unsupervised methods have heightened the diagnostic accuracy of models developed to identify the presence of HF and further augmentation of model capabilities are likely utilizing ensembles of ML algorithms derived from different techniques.

SUMMARY

This article is an overview of recent applications of ML to achieve improved diagnosis of HF and the resultant implications for patient management.

Ultra performance liquid chromatography-tandem mass spectrometry assay for the quantification of RNA and DNA methylation

Previous studies have reported that nucleic acid methylation is a critical element in cardiovascular disease, and most studies mainly focused on sequencing and biochemical research. Here we developed an Ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/ MS) method for the quantification analysis of the dissociative epigenetic modified nucleosides (5mdC, 5mrC, m⁶A) in Myocardial Infarction (MI) SD rats from different periods (1 week, 4 weeks, 8 weeks) after the surgery. The samples for analysis were obtained from heart tissue and blood of the rats. All the quantification results are compared with the sham-operated group. Total RNA and DNA were isolated by enzymatic hydrolytic methods before the UPLC-MS/MS analysis. The statistical analysis demonstrates the dynamic changes of modified nucleosides in MI rats, and it showed good specificity, accuracy, stability and less samples were needed in the method. In this paper, we discovered that the concentration of 5mdC, 5mrC, m⁶A from heart tissue significantly increased at 8 weeks after the surgery. Furthermore, UPLC-MS/MS helps us observe the similar change of the concentration of those 3 methylated biomarkers in peripheral blood after 8 weeks. The result shows that the dynamic process of those 3 methylated biomarkers in peripheral blood is related to the content of methylated biomarkers from the heart tissue. Based on the scientific evidence available, we proved that the methylation of genetic materials in peripheral blood is similar to myocardial infarction tissue. The relation between them indicates that peripheral blood could be a promising alternative to the heart tissue which monitor the level of methylation and MI diagnosis-aided.

Exercise Stress Real-Time Cardiac Magnetic Resonance Imaging for Noninvasive Characterization of Heart Failure With Preserved Ejection Fraction: The HFpEF-Stress Trial

BACKGROUND

Right heart catheterization using exercise stress is the reference standard for the diagnosis of heart failure with preserved ejection fraction (HFpEF) but carries the risk of the invasive procedure. We hypothesized that real-time cardiac magnetic resonance (RT-CMR) exercise imaging with pathophysiologic data at excellent temporal and spatial resolution may represent a contemporary noninvasive alternative for diagnosing HFpEF.

METHODS

The HFpEF-Stress trial (CMR Exercise Stress Testing in HFpEF; URL: https://www.clinicaltrials.gov; Unique identifier: NCT03260621. URL: https://dzhk.de/; Unique identifier: DZHK-17) prospectively recruited 75 patients with echocardiographic signs of diastolic dysfunction and dyspnea on exertion (E/e'>8, New York Heart Association class ≥II) to undergo echocardiography, right heart catheterization, and RT-CMR at rest and during exercise stress. HFpEF was defined according to pulmonary capillary wedge pressure (≥15 mm Hg at rest or ≥25 mm Hg during exercise stress). RT-CMR functional assessments included time-volume curves for total and early (1/3) diastolic left ventricular filling, left atrial (LA) emptying, and left ventricular/LA long axis strain.

RESULTS

Patients with HFpEF (n=34; median pulmonary capillary wedge pressure at rest, 13 mm Hg; at stress, 27 mm Hg) had higher E/e' (12.5 versus 9.15), NT-proBNP (N-terminal pro-B-type natriuretic peptide; 255 versus 75 ng/L), and LA volume index (43.8 versus 36.2 mL/m²) compared with patients with noncardiac dyspnea (n=34; rest, 8 mm Hg; stress, 18 mm Hg; P≤0.001 for all). Seven patients were excluded because of the presence of non-HFpEF cardiac disease causing dyspnea on imaging. There were no differences in RT-CMR left ventricular total and early diastolic filling at rest and during exercise stress (P≥0.164) between patients with HFpEF and noncardiac dyspnea. RT-CMR revealed significantly impaired LA total and early (P<0.001) diastolic emptying in patients with HFpEF during exercise stress. RT-CMR exercise stress LA long axis strain was independently associated with HFpEF (adjusted odds ratio, 0.657 [95% CI, 0.516-0.838]; P=0.001) after adjustment for clinical and imaging measures and emerged as the best predictor for HFpEF (area under the curve at rest 0.82 versus exercise stress 0.93; P=0.029).

CONCLUSIONS

RT-CMR allows highly accurate identification of HFpEF during physiologic exercise and qualifies as a suitable noninvasive diagnostic alternative. These results will need to be confirmed in multicenter prospective research studies to establish widespread routine clinical use. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03260621. URL: https://dzhk.de/; Unique identifier: DZHK-17.

[The role of diastolic transthoracic stress echocardiography with incremental workload in the evaluation of heart failure with preserved ejection fraction: indications, methodology, interpretation. Expert consensus developed under the auspices of the National Medical Research Center of Cardiology, Society of Experts in Heart Failure (SEHF), and Russian Association of Experts in Ultrasound Diagnosis in Medicine (REUDM)]

Diagnosis of heart failure with preserved ejection fraction (HFpEF) is associated with certain difficulties since many patients with HFpEF have a slight left ventricular diastolic dysfunction and normal filling pressure at rest. Diagnosis of HFpEF is improved by using diastolic transthoracic stress-echocardiography with dosed exercise (or diastolic stress test), which allows detection of increased filling pressure during the exercise. The present expert consensus explains the requirement for using the diastolic stress test in diagnosing HFpEF from clinical and pathophysiological standpoints; defines indications for the test with a description of its methodological aspects; and addresses issues of using the test in special patient groups.

How to diagnose heart failure with preserved ejection fraction: the HFA-PEFF diagnostic algorithm: a consensus recommendation from the Heart Failure Association (HFA) of the European Society of Cardiology (ESC)

Making a firm diagnosis of chronic heart failure with preserved ejection fraction (HFpEF) remains a challenge. We recommend a new stepwise diagnostic process, the 'HFA-PEFF diagnostic algorithm'. Step 1 (P=Pre-test assessment) is typically performed in the ambulatory setting and includes assessment for HF symptoms and signs, typical clinical demographics (obesity, hypertension, diabetes mellitus, elderly, atrial fibrillation), and diagnostic laboratory tests, electrocardiogram, and echocardiography. In the absence of overt non-cardiac causes of breathlessness, HFpEF can be suspected if there is a normal left ventricular ejection fraction, no significant heart valve disease or cardiac ischaemia, and at least one typical risk factor. Elevated natriuretic peptides support, but normal levels do not exclude a diagnosis of HFpEF. The second step (E: Echocardiography and Natriuretic Peptide Score) requires comprehensive echocardiography and is typically performed by a cardiologist. Measures include mitral annular early diastolic velocity (e'), left ventricular (LV) filling pressure estimated using E/e', left atrial volume index, LV mass index, LV relative wall thickness, tricuspid regurgitation velocity, LV global longitudinal systolic strain, and serum natriuretic peptide levels. Major (2 points) and Minor (1 point) criteria were defined from these measures. A score ≥5 points implies definite HFpEF; ≤1 point makes HFpEF unlikely. An intermediate score (2-4 points) implies diagnostic uncertainty, in which case Step 3 (F1: Functional testing) is recommended with echocardiographic or invasive haemodynamic exercise stress tests. Step 4 (F2: Final aetiology) is recommended to establish a possible specific cause of HFpEF or alternative explanations. Further research is needed for a better classification of HFpEF.

Clinical Application of Stress Echocardiography in Management of Heart Failure

The key to understanding hemodynamics in heart failure (HF) is the relation between elevated left ventricular (LV) filling pressure and cardiac output. Some patients show abnormal response to stress in the relationship between LV filling pressure and cardiac output. In patients with preserved diastolic function, cardiac output can be increased without significantly elevated filling pressure during stress. In patients with HF, as long as the Frank-Starling mechanism operates effectively, cardiac output can increase while acquiring elevated filling pressure. In patients with decompensated HF, hemodynamic stress will lead to a much greater elevation in filling pressure and pulmonary venous hypertension.

Diagnosis and Management of Patients with Heart Failure with Preserved Ejection Fraction (HFpEF): Current Perspectives and Recommendations

Heart failure with preserved ejection fraction (HFpEF) is a major global public health problem. Diagnosis of HFpEF is still challenging and built based on the comprehensive echocardiographic analysis. Currently, there are no universally accepted therapies that alter the clinical course of HFpEF. This review attempts to summarize the current advances in the diagnosis of HFpEF and provide future directions of the patients´ management with this very widespread, heterogeneous clinical syndrome.

Tilt-table Echocardiography Unmasks Early Diastolic Dysfunction in Patients With Hemoglobinopathies

Individuals with hemoglobinopathy (sickle cell anemia and thalassemia major) are at risk for cardiac complications such as heart failure and cardiomyopathy. Diastolic dysfunction is known to precede systolic dysfunction in many cardiac diseases. This study sought to determine whether changes in left atrial (LA) function during manipulation of cardiac preload by tilt-table echocardiography can unmask subclinical diastolic dysfunction in pediatric patients with hemoglobinopathies. Eleven sickle cell anemia, 9 transfusion-dependent thalassemia major, and 10 control subjects underwent tilt-table echocardiogram in the supine (loading) and 30-degree upright (unloading) positions and cardiac magnetic resonance imaging (MRI). Echocardiography assessed LA and left ventricular (LV) strain, strain rate, mitral inflow, and annular velocities. MRI assessed LV function, myocardial T1 and T2* for iron deposition. Both thalassemia major and sickle cell anemia patients had normal LV function and no evidence of cardiac iron deposition on MRI T2* measurements. During cardiac loading, controls appropriately increased LA conduit (P=0.002) and reservoir strain (P=0.002), mitral e' velocity (P<0.0001) and medial e' velocity (P=0.002), while the hemoglobinopathy patients showed no change in these parameters. In pediatric sickle cell anemia and thalassemia, tilt-table echocardiography unmasked a failure to augment LA function in response to loading, suggesting altered myocardial relaxation is present, before evidence of iron overload or systolic dysfunction.

Diastolic function assessment by echocardiography: A practical manual for clinical use and future applications

Diastole is an important component of the cardiac cycle, during which time optimum filling of the ventricle determines physiological stroke volume ejected in the succeeding systole. Many factors contribute to optimum ventricular filling including venous return, left atrial filling from the pulmonary circulation, and emptying into the left ventricle. Left ventricular filling is also impacted by the cavity emptying function and also its synchronous function which may suppress early diastolic filling in severe cases of dyssynchrony. Sub-optimum LA emptying increases cavity pressure, causes enlarged left atrium, unstable myocardial function, and hence atrial arrhythmia, even atrial fibrillation. Patients with clear signs of raised left atrial pressure are usually symptomatic with exertional breathlessness. Doppler echocardiography is an ideal noninvasive investigation for diagnosing raised left atrial pressure as well as following treatment for heart failure. Spectral Doppler based increased E/A, shortened E-wave deceleration time, increased E/e', and prolonged atrial flow reversal in the pulmonary veins are all signs of raised left atrial pressure. Left atrial reduced myocardial strain is another correlate of raised cavity pressure (>15 mm Hg). In patients with inconclusive signs of raised left atrial pressure at rest, exercise/stress echocardiography or simply passive leg lifting should identify those with stiff left ventricular which suffers raised filling pressures with increased venous return.

The Utility of Cardiac Reserve for the Early Detection of Cancer Treatment-Related Cardiac Dysfunction: A Comprehensive Overview

With progressive advancements in cancer detection and treatment, cancer-specific survival has improved dramatically over the past decades. Consequently, long-term health outcomes are increasingly defined by comorbidities such as cardiovascular disease. Importantly, a number of well-established and emerging cancer treatments have been associated with varying degrees of cardiovascular injury that may not emerge until years following the completion of cancer treatment. Of particular concern is the development of cancer treatment related cardiac dysfunction (CTRCD) which is associated with an increased risk of heart failure and high risk of morbidity and mortality. Early detection of CTRCD appears critical for preventing long-term cardiovascular morbidity in cancer survivors. However, current clinical standards for the identification of CTRCD rely on assessments of cardiac function in the resting state. This provides incomplete information about the heart's reserve capacity and may reduce the sensitivity for detecting sub-clinical myocardial injury. Advances in non-invasive imaging techniques have enabled cardiac function to be quantified during exercise thereby providing a novel means of identifying early cardiac dysfunction that has proved useful in several cardiovascular pathologies. The purpose of this narrative review is (1) to discuss the different non-invasive imaging techniques that can be used for quantifying different aspects of cardiac reserve; (2) discuss the findings from studies of cancer patients that have measured cardiac reserve as a marker of CTRCD; and (3) highlight the future directions important knowledge gaps that need to be addressed for cardiac reserve to be effectively integrated into routine monitoring for cancer patients exposed to cardiotoxic therapies.

How to diagnose heart failure with preserved ejection fraction: the HFA-PEFF diagnostic algorithm: a consensus recommendation from the Heart Failure Association (HFA) of the European Society of Cardiology (ESC)

Making a firm diagnosis of chronic heart failure with preserved ejection fraction (HFpEF) remains a challenge. We recommend a new stepwise diagnostic process, the 'HFA-PEFF diagnostic algorithm'. Step 1 (P=Pre-test assessment) is typically performed in the ambulatory setting and includes assessment for heart failure symptoms and signs, typical clinical demographics (obesity, hypertension, diabetes mellitus, elderly, atrial fibrillation), and diagnostic laboratory tests, electrocardiogram, and echocardiography. In the absence of overt non-cardiac causes of breathlessness, HFpEF can be suspected if there is a normal left ventricular (LV) ejection fraction, no significant heart valve disease or cardiac ischaemia, and at least one typical risk factor. Elevated natriuretic peptides support, but normal levels do not exclude a diagnosis of HFpEF. The second step (E: Echocardiography and Natriuretic Peptide Score) requires comprehensive echocardiography and is typically performed by a cardiologist. Measures include mitral annular early diastolic velocity (e'), LV filling pressure estimated using E/e', left atrial volume index, LV mass index, LV relative wall thickness, tricuspid regurgitation velocity, LV global longitudinal systolic strain, and serum natriuretic peptide levels. Major (2 points) and Minor (1 point) criteria were defined from these measures. A score ≥5 points implies definite HFpEF; ≤1 point makes HFpEF unlikely. An intermediate score (2-4 points) implies diagnostic uncertainty, in which case Step 3 (F₁ : Functional testing) is recommended with echocardiographic or invasive haemodynamic exercise stress tests. Step 4 (F₂ : Final aetiology) is recommended to establish a possible specific cause of HFpEF or alternative explanations. Further research is needed for a better classification of HFpEF.

Subclinical cardiac stiffness is associated with arterial stiffness in healthy young nulligravid women: Potential links to preeclampsia

OBJECTIVES

Preeclampsia is an independent risk factor for subsequent cardiovascular disease and diastolic dysfunction and has been linked to arterial stiffness. We hypothesized that arterial stiffness would be associated with echocardiographic markers of diastolic dysfunction in healthy nulligravid women.

STUDY DESIGN

31 healthy nulligravid women underwent assessment of peripheral arterial stiffness via aorto-femoral pulse wave velocity, popliteal distensibility and β stiffness measures as well as hemodynamic response to volume challenge. 22 underwent cardiac assessment via conventional and stress echocardiography with a focus on diastolic function utilizing tissue/pulse wave Doppler imaging and 3D speckle tracking. Bivariate associations between variables were evaluated using correlation coefficients (Pearson r) and Student's t-tests.

RESULTS

No participants had echocardiographic values meeting criteria for overt diastolic dysfunction. Baseline global circumferential strain was significantly correlated with distensibility and β stiffness (n = 18, r = -0.61, p = 0.007, n = 18, r = 0.56, p = 0.01). Peak deceleration time was correlated with βstiffness (n = 9; r = 0.80, p = 0.01). Pulse wave velocity was not significantly correlated with cardiac measures (p > 0.05). Family history of a first or second degree relative with myocardial infarction or hypertension was associated with decreased popliteal artery distensibility (p = 0.02 and p = 0.03, respectively).

CONCLUSIONS

In healthy nulligravid women there is evidence that markers of decreased left ventricular relaxation are associated with increased peripheral vascular stiffness as is a family history of myocardial infarction or hypertension. These findings raise the possibility that the diastolic dysfunction and arterial stiffness observed in the setting of preeclampsia are driven by underlying properties present prior to pregnancy and contribute to lifetime cardiovascular risk.

The value of exercise echocardiography in heart failure with preserved ejection fraction

Diastolic stress test is something that is now acknowledged in the recommendations and guidelines for diagnosing heart failure with preserved ejection fraction. This is mainly a submaximal exercise stress test, while the maximal exercise stress test is used in the research of ischemia. Echocardiography can be performed at rest and during submaximal exercise stress test. Few papers have proposed exercise echocardiography as a relevant diagnostic tool in heart failure with preserved ejection fraction. The E/e’ ratio and the estimated pulmonary artery pressure by maximal tricuspid regurgitation velocity should be measured during standardized exercise. Stroke volume and its change during exercise should be also assessed. In fact, unlike in a normal compliant heart, there is no increase in left ventricular end-diastolic volume during exercise and consequently no increase in cardiac output in heart failure with preserved ejection fraction. The absence of increased cardiac output during exercise is, like E/e’ and estimated pulmonary artery pressure, a major parameter to be investigated during submaximal exercise performed to confirm the diagnosis of heart failure with preserved ejection fraction as an etiology of dyspnea.

Resting and Exercise Doppler Hemodynamics: How and Why?

Exercise intolerance is the clinical hallmark of the failing heart. Evidence of hemodynamic derangement is not always present at rest, often necessitating dynamic challenges to accentuate abnormalities. Although cardiac catheterization, particularly with exercise, remains the gold standard method for hemodynamic assessment, it is limited by practicality, access, risk, and its invasive nature; consequently, there is a need to better understand noninvasive measures. Echocardiography and cardiac MRI offer promising modalities to quantify ventriculo-vascular interactions. Significant heterogeneity exists around exercise protocols, and there is a need to develop consensus methodology and to validate these noninvasive measures in all forms of heart failure.

Stress ECHO beyond coronary artery disease. Is it the holy grail of cardiovascular imaging?

Stress echocardiography (SE) is a very useful method in clinical practice, because it offers important information of both the patient's functional status and hemodynamic changes during stress. Therefore, SE provides strong diagnostic and prognostic data in a wide spectrum of cardiovascular diseases. This review summarizes the clinical applications of SE in conditions beyond coronary artery disease (CAD) and highlights practical recommendations and key issues for each condition that need further investigation. SE is an established method for the evaluation of symptomatic and asymptomatic patients with valvular heart disease (VHD) and cardiomyopathies, and provides important information regarding prognosis and management of patients with congenital heart disease, pulmonary hypertension or diastolic dysfunction. Moreover, when one or multiple VHD and cardiomyopathy or CAD coexist in one patient, SE is a very useful clinical tool for the evaluation of etiology and symptomatology.

Diastolic stress test echocardiography in patients with suspected heart failure with preserved ejection fraction: a pilot study

AIMS

The purpose of this pilot study was to assess the potential usefulness of diastolic stress test (DST) echocardiography in patients with suspected heart failure with preserved ejection fraction (HFpEF).

METHODS AND RESULTS

Patients with suspected HFpEF (left ventricular ejection fraction ≥ 50%, exertional dyspnoea, septal E/e' at rest 9-14, and N-terminal pro-B-type natriuretic peptide (NT-proBNP) at rest < 220 pg/mL; n = 13) and a control group constituted from asymptomatic patients with arterial hypertension (n = 19) and healthy subjects (n = 18) were included. All patients were analysed by two-dimensional and Doppler echocardiography at rest and during exercise (DST) and underwent cardiopulmonary exercise testing and NT-proBNP analysis during exercise. HFpEF during exercise was defined as exertional dyspnoea and peak VO₂  ≤ 20.0 mL/min/kg. In patients with suspected HFpEF at rest, 84.6% of these patients developed HFpEF during exercise, whereas in the group of asymptomatic patients with hypertension and healthy subjects, the rate of developed HFpEF during exercise was 0%. Regarding the diagnostic performance of DST to detect HFpEF during exercise, an E/e' ratio >15 during exercise was the most accurate parameter to detect HFpEF (accuracy 86%), albeit a low sensitivity (45.5%). Nonetheless, combining E/e' with tricuspid regurgitation (TR) velocity > 2.8 m/s during exercise provided a significant increase in the sensitivity to detect patients with HFpEF during exercise (sensitivity 72.7%, specificity 79.5%, and accuracy 78%). Consistent with these findings, an increase of E/e' was significantly linked to worse peak VO₂ , and the combination of an increase of both E/e' and TR velocity was associated with elevated NT-proBNP values during exercise.

CONCLUSIONS

The findings of this pilot study suggest that DST using E/e' ratio and TR velocity could be of potential usefulness to diagnose HFpEF during exercise in patients with suspected HFpEF at rest.

Diastolic stress echocardiography: from basic principles to clinical applications

Heart failure with preserved ejection fraction (HFpEF) looms as a major public heart challenge with increasing prevalence due to an ageing population. Diagnosis can be challenging due to non-specific symptomatology, low natriuretic peptide levels and equivocal diastology on resting echocardiography. Diastolic stress echocardiography represents a non-invasive option to refining the diagnosis in this subset of patients. Diastolic responses to exercise are most commonly measured with a non-invasive measure of left ventricular filling pressures (LVFP) estimated by the ratio of the early mitral inflow wave to early diastolic tissue velocity (E/e' ratio). This is measured pre- and post-exercise , and is highly feasible. An elevation of exercise E/e' >15 is classified as an abnormal response as per current guidelines. An alternative measure of exercise-related diastolic performance, the Diastolic Functional Reserve Index has also been proposed, but has not been as well studied as exercise E/e'. A number of studies have validated exercise E/e' as a measure of LVFP against invasively measured LVFP using simultaneous echocardiography-catheterisation studies. The independent prognostic value of exercise E/e' has also been well delineated in a number of studies. While diastolic stress echocardiography can be considered for all patients with suspected HFpEF, it is of particular value in patients with normal or equivocal diastolic indices on resting echocardiography.

The importance of integrated left atrial evaluation: From hypertension to heart failure with preserved ejection fraction

AIM

Functional analysis and measurement of left atrium are an integral part of cardiac evaluation, and they represent a key element during non-invasive analysis of diastolic function in patients with hypertension (HT) and/or heart failure with preserved ejection fraction (HFpEF). However, diastolic dysfunction remains quite elusive regarding classification, and atrial size and function are two key factors for left ventricular (LV) filling evaluation. Chronic left atrial (LA) remodelling is the final step of chronic intra-cavitary pressure overload, and it accompanies increased neurohormonal, proarrhythmic and prothrombotic activities. In this systematic review, we aim to purpose a multi-modality approach for LA geometry and function analysis, which integrates diastolic flow with LA characteristics and remodelling through application of both traditional and new diagnostic tools.

METHODS

The most important studies published in the literature on LA size, function and diastolic dysfunction in patients with HFpEF, HT and/or atrial fibrillation (AF) are considered and discussed.

RESULTS

In HFpEF and HT, pulsed and tissue Doppler assessments are useful tools to estimate LV filling pressure, atrio-ventricular coupling and LV relaxation but they need to be enriched with LA evaluation in terms of morphology and function. An integrated evaluation should be also applied to patients with a high arrhythmic risk, in whom eccentric LA remodelling and higher LA stiffness are associated with a greater AF risk.

CONCLUSION

Evaluation of LA size, volume, function and structure are mandatory in the management of patients with HT, HFpEF and AF. A multi-modality approach could provide additional information, identifying subjects with more severe LA remodelling. Left atrium assessment deserves an accurate study inside the cardiac imaging approach and optimised measurement with established cut-offs need to be better recognised through multicenter studies.

Cardiac function during weaning failure: the role of diastolic dysfunction

Background

Cardiac dysfunction is a common cause of weaning failure. Weaning shares some similarities with a cardiac stress test and may challenge active phases of the cardiac cycle-like ventricular contractility and relaxation. This study aimed at assessing systolic and diastolic function during the weaning process and scrutinizing their dynamics during weaning trials.

Methods

Echocardiography was performed during baseline ventilator settings to assess cardiac function at the initiation of the weaning process and at the start and the end of consecutive weaning trials (performed at day-1, day-2, and before extubation if applicable) to explore the evolution of left ventricle contractility and relaxation in a subset of patients.

Results

Among 67 patients included, weaning was prolonged (≥ 7 days) in 18 (27%) patients and short (< 7 days) in 49 (73%). Prevalence of systolic dysfunction and isolated diastolic dysfunction before the initiation of weaning process were 37 and 17%, respectively. Isolated diastolic dysfunction was more frequent in patients with prolonged weaning as compared to their counterparts. Thirty-one patients were explored by echocardiography during consecutive weaning trials. An increase in filling pressures with an alteration of ventricular relaxation (as assessed by a decrease in tissue Doppler early mitral diastolic wave velocity) was found during failed weaning trials.

Conclusions

Isolated diastolic dysfunction was associated with a prolongation of weaning. Increased filling pressures with left ventricle relaxation impairment may be a key mechanism of weaning trial failure.

Electronic supplementary material

The online version of this article (10.1186/s13613-017-0348-4) contains supplementary material, which is available to authorized users.

Influence of androgen on myocardial apoptosis and expression of myocardial IR and IRS‑1 in chronic heart failure rat models

The present study aimed to investigate the effect of androgens on chronic heart failure (CHF) in a rat model. A total of 120 Sprague Dawley male rats were randomly divided into the following groups: (A) sham operation group, (B) castrated group, (C) heart failure (HF) group, (D) castrated + HF group, and (E) castrated + HF + testosterone (T) replacement therapy group. There were 20 rats in group A, and 25 rats in the other groups. Surgical castration was performed on groups B, D and E, and T replacement therapy was administered to group E. Groups C, D and E were treated with doxorubicin hydrochloride to prepare the CHF animal model. The insulin sensitivity index (ISI) was calculated from fasting blood glucose and fasting insulin levels. Echocardiography was performed. Venous blood was collected for plasma T level test. Myocardial tissue was used for apoptosis index analysis. The expression levels of myocardial insulin receptor (IR) and insulin receptor substrate‑1 (IRS‑1) were measured by reverse transcription semi‑quantitative polymerase chain reaction. Compared with group A, the T level and ISI decreased, whereas the expression level of IR and IRS‑1 were increased in the CHF group (P<0.05). Following castration, the T level and ISI were significantly decreased, and the expression of IR and IRS‑1 were increased compared with the uncastrated CHF rats (P<0.01). Following androgen administration, the ISI increased, expression of IR and IRS‑1 decreased, and the myocardial apoptosis index decreased (P<0.05). Taken together, these results demonstrated that androgen supplementation could improve insulin resistance and affect the expression of IR and IRS‑1 in CHF, thereby reducing myocardial apoptosis and improving cardiac function.

Heart failure

Heart failure is common in adults, accounting for substantial morbidity and mortality worldwide. Its prevalence is increasing because of ageing of the population and improved treatment of acute cardiovascular events, despite the efficacy of many therapies for patients with heart failure with reduced ejection fraction, such as angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), β blockers, and mineralocorticoid receptor antagonists, and advanced device therapies. Combined angiotensin receptor blocker neprilysin inhibitors (ARNIs) have been associated with improvements in hospital admissions and mortality from heart failure compared with enalapril, and guidelines now recommend substitution of ACE inhibitors or ARBs with ARNIs in appropriate patients. Improved safety of left ventricular assist devices means that these are becoming more commonly used in patients with severe symptoms. Antidiabetic therapies might further improve outcomes in patients with heart failure. New drugs with novel mechanisms of action, such as cardiac myosin activators, are under investigation for patients with heart failure with reduced left ventricular ejection fraction. Heart failure with preserved ejection fraction is a heterogeneous disorder that remains incompletely understood and will continue to increase in prevalence with the ageing population. Although some data suggest that spironolactone might improve outcomes in these patients, no therapy has conclusively shown a significant effect. Hopefully, future studies will address these unmet needs for patients with heart failure. Admissions for acute heart failure continue to increase but, to date, no new therapies have improved clinical outcomes.

Role of cardiopulmonary exercise testing in clinical stratification in heart failure. A position paper from the Committee on Exercise Physiology and Training of the Heart Failure Association of the European Society of Cardiology

Traditionally, the main indication for cardiopulmonary exercise testing (CPET) in heart failure (HF) was for the selection of candidates to heart transplantation: CPET was mainly performed in middle-aged male patients with HF and reduced left ventricular ejection fraction. Today, CPET is used in broader patients' populations, including women, elderly, patients with co-morbidities, those with preserved ejection fraction, or left ventricular assistance device recipients, i.e. individuals with different responses to incremental exercise and markedly different prognosis. Moreover, the diagnostic and prognostic utility of symptom-limited CPET parameters derived from submaximal tests is more and more considered, since many patients are unable to achieve maximal aerobic power. Repeated tests are also being used for risk stratification and evaluation of intervention, so that these data are now available. Finally, patients, physicians and healthcare decision makers are increasingly considering how treatments might impact morbidity and quality of life rather than focusing more exclusively on hard endpoints (such as mortality) as was often the case in the past. Innovative prognostic flowcharts, with CPET at their core, that help optimize risk stratification and the selection of management options in HF patients, have been developed.

A prospective evaluation of the established criteria for heart failure with preserved ejection fraction using the Alberta HEART cohort

Aims

Heart failure with a preserved ejection fraction (HF‐PEF) remains a difficult clinical diagnosis. The aim of this study was to test the utility of established criteria to classify patients with HF‐PEF. We prospectively enrolled patients into one of five groups across a spectrum of cardiac disease and applied three different criteria for HF‐PEF and calculated diagnostic metrics.

Methods and results

A total of 565 patients were included in the analysis, including 170 patients with an adjudicated diagnosis of HF‐PEF, 152 patients with heart failure with reduced ejection fraction, 152 patients at risk for heart failure, and 91 age‐matched healthy controls. For the diagnosis of HF‐PEF, the positive likelihood ratios were 6.1, 6.9, and 4.8 for the Zile, European Society of Cardiology (ESC) 2007, and ESC 2016 criteria, respectively. The negative likelihood ratios were 0.58, 0.60, and 0.42 for the Zile, ESC 2007, and ESC 2016 criteria, respectively. All three criteria lacked sensitivity to detect HF‐PEF (46.5%, 44.1%, and 51.8%, respectively) but were highly specific (92.4%, 93.9%, and 89%, respectively). We further evaluated the criteria to distinguish HF‐PEF from other diagnoses after excluding heart failure with reduced ejection fraction; the results were similar.

Conclusions

In this community based cohort, the likelihood ratios of the existing criteria for HF‐PEF were not at the level necessary to be considered diagnostic. Improved criteria for the diagnosis of patients with HF‐PEF are needed.

What Is the Evidence That the Tissue Doppler Index E/e' Reflects Left Ventricular Filling Pressure Changes After Exercise or Pharmacological Intervention for Evaluating Diastolic Function? A Systematic Review

Background

Noninvasive echocardiographic tissue Doppler assessment (E/e′) in response to exercise or pharmacological intervention has been proposed as a useful parameter to assess left ventricular (LV) filling pressure (LVFP) and LV diastolic dysfunction. However, the evidence for it is not well summarized.

Methods and Results

Clinical studies that evaluated invasive LVFP changes in response to exercise/other interventions and echocardiographic E/e′ were identified from PubMed, Scopus, Embase, and Cochrane Library databases. We grouped and evaluated studies that included patients with preserved LV ejection fraction (LVEF), patients with mixed/reduced LVEF, and patients with specific cardiac conditions. Overall, we found 28 studies with 9 studies for preserved LVEF, which was our primary interest. Studies had differing methodologies with limited data sets, which precluded quantitative meta‐analysis. We therefore descriptively summarized our findings. Only 2 small studies (N=12 and 10) directly or indirectly support use of E/e′ for assessing LVFP changes in preserved LVEF. In 7 other studies (cumulative N=429) of preserved LVEF, E/e′ was not useful for assessing LVFP changes. For mixed/reduced LVEF groups or specific cardiac conditions, results similar to preserved LVEF were found.

Conclusions

We find that there is insufficient evidence that E/e′ can reliably assess LVFP changes in response to exercise or other interventions. We suggest that well‐designed prospective studies should be conducted for further evaluation.

Diastolic stress echocardiography

Evaluation of diastolic dysfunction and diagnosis of heart failure with preserved ejection fraction (HFpEF) by echocardiography are routinely performed at rest. However, many patients with modest HFpEF develop symptoms such as dyspnea only during exercise. Therefore, echocardiographic analysis at rest could be insufficient to identify these patients. Recent studies have demonstrated the utility of diastolic stress echocardiography to evaluate diastolic dysfunction during exercise. This review attempts to summarize and discuss current studies in diastolic stress echocardiography.

Low level exercise echocardiography helps diagnose early stage heart failure with preserved ejection fraction: a study of echocardiography versus catheterization

BACKGROUND

Increased left ventricular end-diastolic pressure (LVEDP) with exercise is an early sign of heart failure with preserved left ventricular ejection fraction (LVEF). The abnormal exercise increase in LVEDP is nonlinear, with most change occurring at low-level exercise. Data on non-invasive approach of this condition are scarce. Our objective was assessing E/e' to estimate low level exercise LVEDP using a direct invasive measurement as the reference method.

METHODS AND RESULTS

Sixty patients with LVEF >50 % prospectively underwent both exercise cardiac catheterization and echocardiography. E/e' was measured at rest and during low-level exercise. Abnormal LVEDP was defined as >16 mmHg. Patients with a history of coronary artery disease and/or abnormal LV morphology were classified as having apparent cardiac disease (CD). Thirty-four (57 %) patients had elevated LVEDP only during exercise. Most of the change in LVEDP occurred since the first exercise level (25 W). There was a correlation between LVEDP and septal E/e' at rest and during exercise. Lateral E/e' and E/average e' ratio had worse correlations with LVEDP. In the whole population, exercise septal E/e' at 25 W had the best accuracy for abnormal exercise LVEDP, area under curve (AUC) = 0.79. However, while low-level exercise septal E/e' had a high accuracy in CD patients (n = 26, AUC = 0.96), E/e' was not linked to LVEDP in patients without CD (n = 34).

CONCLUSION

Low-level exercise septal E/e' is valuable for predicting abnormal exercise LVEDP in patients with preserved LVEF and apparent CD. However, this new diagnosis approach appears not reliable in patients with normal LV morphology and without coronary artery disease.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov . Unique identifier: NCT01714752.

Comparison of echocardiographic parameters between pre-clinical and clinical advanced diastolic dysfunction patients

BACKGROUND

The diagnosis of heart failure (HF) with preserved ejection fraction requires evidence of grade 2 or 3 (advanced) diastolic dysfunction (ADD), but many patients with ADD do not have clinical HF manifestations, hence termed pre-clinical diastolic dysfunction (PDD). The prevalence and characteristics of PDD in comparison to overt HF disease (clinical-ADD) are still debated.

METHODS

We retrospectively analyzed 373 patients with LVEF≥45% and ADD in our echo-lab database. Exclusion criteria were acute coronary syndromes, ≥moderate valvular disease, cardiomyopathies or pericardial disease. Patients were divided into 2 groups according to the presence/absence of HF symptoms, namely PDD (n=249) and clinical-ADD (n=124). Demographic, clinical and echocardiographic parameters were compared between the groups.

RESULTS

Age, gender and comorbidities were similar between groups, with only a higher body mass index and renal failure significantly more prevalent in the clinical-ADD patients. Neither LV mass nor the ADD severity was related to the presence of symptoms; lateral mitral E/E' and pulmonary artery systolic pressure were significantly higher in clinical-ADD patients (14±5 vs. 12±4, p<0.05 and 40±13 vs. 36±11mmHg, p<0.05, respectively) and were the only parameters to correlate with the presence of symptoms of clinical-ADD in multivariable logistic regression (odds ratio=1.07 (CI 1.02-1.1, p=0.008) and 1.03 (CI 1.01-1.05, p=0.01), respectively).

CONCLUSIONS

In patients referred for an echocardiogram at a community cardiology center, PDD was twice as common as clinical-ADD. Hemodynamic parameters reflecting elevated filling and pulmonary pressures, rather than traditional comorbidities and/or classical structural abnormalities, were the only parameters related to the presence of HF symptoms.