Variability in approach to exercise stress echocardiography for diagnosis of heart failure with preserved ejection fraction: an international survey on real-world practice.

Aims: The diagnosis of heart failure with preserved ejection fraction (HFpEF) remains challenging based on resting assessments. Exercise echocardiography is often used to unmask abnormalities that develop during exercise, but the diagnostic criteria have not been standardized. This study aimed to elucidate how cardiologists utilize exercise echocardiography to diagnose HFpEF in real-world practice. Methods and results: An international web-based survey involving 87 cardiologists was performed. We also performed a retrospective cross-sectional study to investigate the impact of different exercise echocardiographic diagnostic criteria in 652 dyspnoeic patients who underwent exercise echocardiography. The HFA-PEFF algorithm was the most commonly used exercise echocardiography criterion for HFpEF diagnoses (48%), followed by the ASE/EACVI criteria (24%) and other combinations of multiple parameters (22%). Among 652 patients, the proportion of HFpEF diagnosis varied substantially according to the criteria used ranging from 20.1% (ASE/EACVI criteria) to 44.3% (HFA-PEFF algorithm). Many cases (49.4-70.5%) remained indeterminate after exercise echocardiography, but only 41% of surveyed cardiologists would utilize exercise right heart catheterization to resolve an indeterminate result. Despite these diagnostic uncertainties, 54% of surveyed cardiologists would utilize exercise echocardiography results to initiate sodium-glucose co-transporter 2 inhibitors. Conclusion: In real-world practice, exercise echocardiographic criteria utilized across cardiologists vary, which meaningfully impacts the frequency of HFpEF diagnoses, with indeterminate results being common. Despite these diagnostic uncertainties, many cardiologists initiate pharmacotherapy based on exercise echocardiography. The lack of consensus on universal diagnostic criteria for exercise echocardiography and approaches to indeterminate results may limit the delivery of evidence-based treatment for HFpEF.

Racial Differences of Cardiac Structure and Function in Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Potential race differences in cardiac structure and function among patients with heart failure with preserved ejection fraction (HFpEF) are not well-understood, but may have pathophysiological and treatment implications. METHODS AND RESULTS: In this study, patients with HFpEF who self-identified as Asian (n = 360), White (n = 787), and Black (n = 171) from 3 institutions underwent comprehensive transthoracic echocardiography to evaluate for potential differences. The Asian HFpEF group was oldest and the Black HFpEF group was youngest (75 ± 12 years vs 73 ± 13 years vs 62 ± 12 years; P < .0001). Women constituted the lowest proportion of patients with HFpEF among Asian individuals, but were the largest among Black patients (49% vs 56% vs 73%; P < .0001). Body mass index and obesity prevalence were highest in Black patients with HFpEF and were lowest in Asian patients. Black individuals with HFpEF had greater left ventricular (LV) wall thickening and concentricity, smaller LV chamber size, leftward-shifted LV end-diastolic pressure-volume relationship, indicating greater LV stiffening, smallest left atrial volumes, and the most right ventricular dilatation. Asian individuals with HFpEF had greater LV and left atrial dilation, more rightward shifted LV end-diastolic pressure-volume relationship, and the highest arterial stiffness. CONCLUSIONS: In summary, we show that patients with HFpEF of Asian, Black, and White race display key differences in clinical, anthropometric, and cardiac structure-function indices, indicating that consideration of race-related differences might important to individualize treatment strategies in HFpEF.

Impaired Left Atrial Reserve Function in Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Left atrial (LA) dysfunction is common in heart failure (HF) with preserved ejection fraction. However, data on the pathophysiologic impacts of impaired LA functional reserve remained limited. We sought to determine the association of abnormal LA dynamics during exercise with cardiovascular reserve, exercise capacity, and clinical outcomes. METHODS: Patients with HF with preserved ejection fraction (n=231) and controls without HF (n=219) underwent exercise stress echocardiography with simultaneous expired gas analysis. LA function was assessed at rest and during exercise using speckle-tracking echocardiography. RESULTS: Patients with HF with preserved ejection fraction demonstrated less increase in LA reservoir and booster pump strain during exercise than those in controls. The degree of LA dilation was more closely related to exercise LA reservoir strain than to resting LA strain (Meng test, P=0.002). The presence of impaired LA reservoir strain during exercise was associated with poorer biventricular systolic reserve and cardiac output augmentation, more severe right ventricular-pulmonary artery uncoupling, and lower peak oxygen consumption. Patients with a lower exercise LA reservoir strain had a 2.7-fold increased risk of HF events (hazard ratio, 2.66 [95% CI, 1.32-5.38]; P=0.006). Among patients with follow-up echocardiography, initiation of guideline-directed medical therapy or atrial fibrillation ablation showed significant improvements in LA reservoir (P<0.001 and P=0.022) and booster pump strain (P=0.011 and 0.028) at rest and during exercise, respectively. CONCLUSIONS: Impaired LA reservoir function during exercise in HF with preserved ejection fraction is associated with biventricular reserve limitations, exercise intolerance, and increased risks of HF events.

Clinical Outcomes of Mitral Valve Surgery in Atrial Functional Mitral Regurgitation in the REVEAL-AFMR Registry.

Importance: The characteristics and treatment strategies of atrial functional mitral regurgitation (AFMR) are poorly understood. Objective: To investigate the prevalence, clinical characteristics, and outcomes of mitral valve (MV) surgery in AFMR. Design, Setting, and Participants: This retrospective cohort study, called the Real-World Observational Study for Investigating the Prevalence and Therapeutic Options for Atrial Functional Mitral Regurgitation (REVEAL-AFMR), was conducted across 26 Japanese centers (17 university hospitals, 1 national center, 3 public hospitals, and 5 private hospitals). All transthoracic echocardiography procedures performed from January 1 to December 31, 2019, were reviewed to enroll adult patients (aged ≥20 years) with moderate or severe AFMR, defined by preserved left ventricular function, a dilated left atrium, and an absence of degenerative valvular changes. Data were analyzed from May 8, 2023, to May 16, 2024. Exposures: Mitral valve surgery, with or without tricuspid valve intervention. Main Outcomes and Measures: The primary composite outcome included heart failure hospitalization and all-cause mortality. Results: In 177 235 patients who underwent echocardiography, 8867 had moderate or severe MR. Within this group, 1007 (11.4%) were diagnosed with AFMR (mean [SD] age, 77.8 [9.5] years; 55.7% female), of whom 807 (80.1%) had atrial fibrillation. Of these patients, 113 underwent MV surgery, with 92 (81.4%) receiving concurrent tricuspid valve surgery. Patients who underwent surgery were younger but had more severe MR (57.5% [n = 65] vs 9.4% [n = 84]; P < .001), a larger mean (SD) left atrial volume index (152.5 [97.8] mL/m2 vs 87.7 [53.1] mL/m2; P < .001), and a higher prevalence of heart failure (according to the New York Heart Association class III [marked limitation of physical activity] or class IV [symptoms of heart failure at rest], 26.5% [n = 30] vs 9.3% [n = 83]; P < .001) than those who remained under medical therapy. During a median follow-up of 1050 days (IQR, 741-1188 days), 286 patients (28.4%) experienced the primary outcome. Despite a more severe disease status, only the surgical group showed a decrease in natriuretic peptide levels at follow-up and had a significantly lower rate of the primary outcome (3-year event rates were 18.3% vs 33.3%; log-rank, P = .03). Statistical adjustments did not alter these findings. Conclusions and Relevance: The findings of this cohort study suggest that in patients with AFMR, who were typically older and predominantly had atrial fibrillation, MV surgery was associated with lower rates of adverse clinical outcomes. Future studies are warranted to investigate a possible causal relationship to better regulate cardiovascular medicine.

The Multicenter STudy On a Precise algorithm for diagnosis of heart failure with preserved ejection fraction, STOP-HFPEF study: study protocol and design.

This study aims to develop a new heart failure with preserved ejection fraction (HFpEF) diagnostic algorithm tailored to Asian populations, addressing limitations of current diagnostic models. Existing HFpEF diagnostic algorithms primarily target patients with dyspnea and metabolic comorbidities, such as obesity, which are more prevalent in Western populations. However, in Asian countries, HFpEF cases are less frequently associated with obesity, leading to less prominent dyspnea and more noticeable symptoms such as fatigue. By incorporating exercise stress echocardiography and focusing on early-stage HFpEF, particularly in patients with symptoms beyond dyspnea, we seek to enable early diagnosis and intervention, ultimately extending healthy life expectancy and improving quality of life. The STOP-HFPEF (The Multicenter STudy On a Precise algorithm for diagnosis of Heart Failure with Preserved Ejection Fraction) study is a multicenter prospective observational investigation in Japan. Certified by the Japanese Society of Echocardiography, the study includes participants aged 20 and older who undergo exercise stress echocardiography. The primary goal is to develop a scoring model for diagnosing HFpEF in heart-failure stages A, B, and C. Secondary outcomes will assess the clinical utility of the new diagnostic score by comparing heart-failure incidence, cardiovascular events, and mortality rates.Study registration: Registered at the UMIN registry (UMIN000054565) on 1 July 2024.

An evidence-based screening tool for heart failure with preserved ejection fraction: the HFpEF-ABA score.

Heart failure with preserved ejection fraction (HFpEF) is under-recognized in clinical practice. Although a previously developed risk score, termed H2FPEF, can be used to estimate HFpEF probability, this score requires imaging data, which is often unavailable. Here we sought to develop an HFpEF screening model that is based exclusively on clinical variables and that can guide the need for echocardiography and further testing. In a derivation cohort (n = 414, 249 women), a clinical model using age, body mass index and history of atrial fibrillation (termed the HFpEF-ABA score) showed good discrimination (area under the curve (AUC) = 0.839 (95% confidence interval (CI) = 0.800-0.877), P < 0.0001). The performance of the model was validated in an international, multicenter cohort (n = 736, 443 women; AUC = 0.813 (95% CI = 0.779-0.847), P < 0.0001) and further validated in two additional cohorts: a cohort including patients with unexplained dyspnea (n = 228, 136 women; AUC = 0.840 (95% CI = 0.782-0.900), P < 0.0001) and a cohort for which HF hospitalization was used instead of hemodynamics to establish an HFpEF diagnosis (n = 456, 272 women; AUC = 0.929 (95% CI = 0.909-0.948), P < 0.0001). Model-based probabilities were also associated with increased risk of HF hospitalization or death among patients from the Mayo Clinic (n = 790) and a US national cohort across the Veteran Affairs health system (n = 3076, 110 women). Using the HFpEF-ABA score, rapid and efficient screening for risk of undiagnosed HFpEF can be performed in patients with dyspnea using only age, body mass index and history of atrial fibrillation.

Cardiac function, haemodynamics, and valve competence with exercise in patients with heart failure with preserved ejection fraction and mild to moderate secondary mitral regurgitation.

AIMS: This study aimed to evaluate the clinical significance of secondary mitral regurgitation (MR) in patients with heart failure with preserved ejection fraction (HFpEF). METHODS AND RESULTS: We conducted a prospective study enrolling consecutively evaluated patients with HFpEF undergoing invasive haemodynamic exercise testing with simultaneous echocardiography. Compared to HFpEF without MR (n = 145, 79.7%), those with mild or moderate MR (n = 37, 20.3%) were older, more likely to be women, had more left ventricular (LV) systolic dysfunction, and more likely to have left atrial (LA) myopathy reflected by greater burden of atrial fibrillation, more LA dilatation, and poorer LA function. Pulmonary artery (PA) wedge pressure was higher at rest in HFpEF with MR (17 ± 5 mmHg vs. 20 ± 5 mmHg, p = 0.005), but there was no difference with exercise. At rest, only 2 (1.1%) patients had moderate MR, and none developed severe MR. Pulmonary vascular resistance was higher, and right ventricular (RV)-PA coupling was more impaired in patients with HFpEF and MR at rest and exercise. LV and LA myocardial dysfunction remained more severe in patients with MR during stress compared to those without MR, characterized by greater LA dilatation during all stages of exertion, lower LA emptying fraction and compliance, steeper and rightward-shifted LA pressure-volume relationships, and reduced LV longitudinal contractile function. CONCLUSIONS: Patients with HFpEF and mild or moderate MR have more severe LV systolic dysfunction, LA myopathy, RV-PA uncoupling, and more severe pulmonary vascular disease. Mitral valve incompetence in this setting is a phenotypic marker of more advanced disease but is not a causal factor in development of HFpEF.

The roles of exercise stress echocardiography for the evaluation of heart failure with preserved ejection fraction in the heart failure pandemic era.

Heart failure with preserved ejection fraction (HFpEF) accounts for nearly 70% of all HF and has become the dominant form of HF. The increased prevalence of HFpEF has contributed to a rise in the number of HF patients, known as the "heart failure pandemic". In addition to the fact that HF is a progressive disease and a delayed diagnosis may worsen clinical outcomes, the emergence of disease-modifying treatments such as sodium-glucose transporter 2 inhibitors and glucagon-like peptide-1 receptor agonists has made appropriate and timely identification of HFpEF even more important. However, diagnosis of HFpEF remains challenging in patients with a lower degree of congestion. In addition to normal EF, this is related to the fact that left ventricular (LV) filling pressures are often normal at rest but become abnormal during exercise. Exercise stress echocardiography can identify such exercise-induced elevations in LV filling pressures and facilitate the diagnosis of HFpEF. Exercise stress echocardiography may also be useful for risk stratification and assessment of exercise tolerance as well as cardiovascular responses to exercise. Recent attention has focused on dedicated dyspnea clinics to identify early HFpEF among patients with unexplained dyspnea and to investigate the causes of dyspnea. This review discusses the role of exercise stress echocardiography in the diagnosis and evaluation of HFpEF.

Prognostic utility of cardiopulmonary exercise testing with simultaneous exercise echocardiography in heart failure with preserved ejection fraction.

AIMS: Cardiopulmonary exercise testing (CPET) combined with exercise echocardiography (CPETecho) allows simultaneous assessments of cardiac, pulmonary, and ventilation in heart failure (HF) with preserved ejection fraction (HFpEF). This study sought to determine whether simultaneous assessment of CPET variables could provide additive predictive value over exercise stress echocardiography in patients with dyspnoea. METHODS AND RESULTS: CPETecho was performed in 443 patients with suspected HFpEF (240 HFpEF and 203 controls without HF). Patients with HFpEF were divided based on peak oxygen consumption (VO2, ≥10 or <10 ml/min/kg) or the slope of minute ventilation to carbon dioxide production (VE vs. VCO2 slope ≥45.0 or <45.0). The primary endpoint was defined as a composite of all-cause mortality, HF hospitalization, unplanned hospital visits requiring intravenous diuretics, or intensification of oral diuretics. During a median follow-up of 399 days, the composite outcome occurred in 57 patients. E/e' ratio during peak exercise was associated with adverse outcomes. Patients with HFpEF and lower peak VO2 had increased risks of the composite event (hazard ratio [HR] 5.05, 95% confidence interval [CI] 2.65-9.62, p < 0.0001 vs. controls; HR 3.14, 95% CI 1.69-5.84, p = 0.0003 vs. HFpEF with higher peak VO2). Elevated VE versus VCO2 slope was also associated with adverse events in HFpEF. The addition of either the presence of abnormal peak VO2 or VE versus VCO2 slope increased the predictive ability over the model based on age, sex, atrial fibrillation, left atrial volume index, and exercise E/e' (p < 0.05). CONCLUSION: These data provide new insights into the role of CPETecho in patients with HFpEF.

Exercise Stress Echocardiography-Based Phenotyping of Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome requiring improved phenotypic classification. Previous studies have identified subphenotypes of HFpEF, but the lack of exercise assessment is a major limitation. The aim of this study was to identify distinct pathophysiologic clusters of HFpEF based on clinical characteristics, and resting and exercise assessments. METHODS: A total of 265 patients with HFpEF underwent ergometry exercise stress echocardiography with simultaneous expired gas analysis. Cluster analysis was performed by the K-prototype method with 21 variables (10 clinical and resting echocardiographic variables and 11 exercise echocardiographic parameters). Pathophysiologic features, exercise tolerance, and prognosis were compared among phenogroups. RESULTS: Three distinct phenogroups were identified. Phenogroup 1 (n = 112 [42%]) was characterized by preserved biventricular systolic reserve and cardiac output augmentation. Phenogroup 2 (n = 58 [22%]) was characterized by a high prevalence of atrial fibrillation, increased pulmonary arterial and right atrial pressures, depressed right ventricular systolic functional reserve, and impaired right ventricular-pulmonary artery coupling during exercise. Phenogroup 3 (n = 95 [36%]) was characterized by the smallest body mass index, ventricular and vascular stiffening, impaired left ventricular diastolic reserve, and worse exercise capacity. Phenogroups 2 and 3 had higher rates of composite outcomes of all-cause mortality or heart failure events than phenogroup 1 (log-rank P = .02). CONCLUSION: Exercise echocardiography-based cluster analysis identified three distinct phenogroups of HFpEF, with unique exercise pathophysiologic features, exercise capacity, and clinical outcomes.

Practice guidance for stress echocardiography.

Stress echocardiography has been one of the most promising methods for the diagnosis of ischemic heart disease, hypertrophic cardiomyopathy, and pulmonary hypertension. The Japanese Society of Echocardiography produced practical guidance for the implementation of stress echocardiography in 2018. At that time, stress echocardiography was not yet widely disseminated in Japan; therefore, the 2018 practical guidance for the implementation of stress echocardiography included a report on stress echocardiography and a specific protocol to promote its use at many institutions in Japan in the future. And now, an era of renewed interest and enthusiasm surrounding the diagnosis and treatment of valvular heart disease and heart failure with preserved ejection fraction (HFpEF) has come, which are driven by emerging trans-catheter procedures and new recommended guideline-directed medical therapy. Based on the continued evidence of stress echocardiography, the new practical guideline that describes the safe and effective methodology of stress echocardiography is now created by the Guideline Development Committee of the Japanese Society of Echocardiography and is designed to expand the use of stress echocardiography for valvular heart disease and HFpEF, as well as ischemic heart disease, hypertrophic cardiomyopathy, and pulmonary hypertension. The readers are encouraged to perform stress echocardiography which will enhance the diagnosis and management of these patients.

Prevalence and risk factors for medication-refractory reflux esophagitis in patients with systemic sclerosis in Japan.

BACKGROUNDS: Patients with systemic sclerosis (SSc) often have esophageal motility abnormalities and weak esophago-gastric junction (EGJ) barrier function, which causes proton pump inhibitor (PPI)-refractory reflux esophagitis (RE). The aims of this study were to clarify the current management of RE and prevalence and risk factors of medication-refractory RE in patients with SSc in Japan. METHODS: A total of 188 consecutive patients with SSc who underwent both esophageal high-resolution manometry (HRM) and esophagogastroduodenoscopy (EGD) were reviewed. The presence of RE and grades of the gastroesophageal flap valve (GEFV) were assessed. Esophageal motility was assessed retrospectively according to the Chicago classification v3.0. When RE was seen on a standard dose of PPI or any dose of vonoprazan (VPZ), it was defined as medication-refractory RE. RESULTS: Approximately 80% of patients received maintenance therapy with acid secretion inhibitors regardless of esophageal motility abnormalities. Approximately 50% of patients received maintenance therapy with PPI, and approximately 30% of patients received VPZ. Medication-refractory RE was observed in 30 patients (16.0%). In multivariable analyses, the number of EGD and absent contractility were significant risk factors for medication-refractory RE. Furthermore, combined absent contractility and GEFV grade III or IV had higher odds ratios than did absent contractility alone. CONCLUSIONS: Patients with persistent reflux symptoms and those with absent contractility and GEFV grade III or IV should receive maintenance therapy with strong acid inhibition to prevent medication-refractory RE.

Characterization and prognostic importance of chronotropic incompetence in heart failure with preserved ejection fraction.

BACKGROUND: Exercise intolerance is the primary symptom of patients with heart failure with preserved ejection fraction (HFpEF). Chronotropic incompetence has been considered to be common and contribute to poor exercise capacity in HFpEF. However, clinical characteristics, pathophysiology, and outcomes of chronotropic incompetence in HFpEF remain poorly understood. METHODS: Patients with HFpEF (n = 246) underwent ergometry exercise stress echocardiography with simultaneous expired gas analysis. The patients were divided into two groups based on the presence of chronotropic incompetence, which was defined by heart rate reserve <0.80. RESULTS: Chronotropic incompetence was common in HFpEF (n = 112, 41 %). Compared to HFpEF patients with a normal chronotropic response (n = 134), those with chronotropic incompetence had higher body mass index, a higher prevalence of diabetes, more frequent ß-blocker use, and worse New York Heart Association class. During peak exercise, patients with chronotropic incompetence demonstrated less increase in cardiac output and arterial oxygen delivery (cardiac output × saturation × hemoglobin × 1.34 × 10), higher metabolic work (peak oxygen consumption [VO2]/watt), an inability to increase arteriovenous oxygen difference, and poorer exercise capacity (lower peak VO2) than those without. Chronotropic incompetence was associated with higher rates of a composite of all-cause mortality or worsening HF events (hazard ratio, 2.66, 95 % confidence intervals, 1.16-6.09, p = 0.02). CONCLUSION: Chronotropic incompetence is common in HFpEF, and is associated with unique pathophysiologic characteristics during exercise and clinical outcomes.

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.

Biatrial myopathy in heart failure with preserved ejection fraction.

AIM: Left atrial (LA) myopathy is increasingly recognized as an important phenotypic trait in heart failure (HF) with preserved ejection fraction (HFpEF). Right atrial (RA) remodelling and dysfunction also develop in HFpEF, but little data are available regarding the clinical characteristics and pathophysiology among patients with isolated LA, RA, or biatrial myopathy. METHODS AND RESULTS: Patients with HFpEF underwent invasive haemodynamic exercise testing, comprehensive imaging including speckle tracking strain echocardiography, and clinical follow-up at Mayo Clinic between 2006 and 2018. LA myopathy was defined as LA volume index >34 ml/m2 and/or LA reservoir strain ≤24% and RA myopathy by RA volume index >39 ml/m2 in men and >33 ml/m2 in women and/or RA reservoir strain ≤19.8%. Of 476 consecutively evaluated patients with HFpEF defined by invasive exercise testing with evaluable atrial structure/function, 125 (26%) had no atrial myopathy, 147 (31%) had isolated LA myopathy, 184 (39%) had biatrial myopathy, and 20 (4%) had isolated RA myopathy. Patients with HFpEF and biatrial myopathy had more atrial fibrillation, poorer left ventricular systolic and diastolic function, more severe pulmonary vascular disease, tricuspid regurgitation, ventricular interdependence and right ventricular dysfunction, and poorer cardiac output reserve with exercise. There were 94 patients with events over a median follow-up of 2.9 (interquartile range 1.4-4.6) years. Individuals with biatrial myopathy had an 84% higher risk of HF hospitalization or death as compared to those with isolated LA myopathy (hazard ratio 1.84; 95% confidence interval 1.16-2.92, p = 0.01). CONCLUSIONS: Biatrial myopathy identifies patients with more advanced HFpEF characterized by more severe pulmonary vascular disease, right HF, poorer cardiac reserve, and a greater risk for adverse outcomes. Further study is required to define optimal strategies to treat and prevent biatrial myopathy in HFpEF.

Inorganic Nitrite to Amplify the Benefits and Tolerability of Exercise Training in Heart Failure With Preserved Ejection Fraction: The INABLE-Training Trial.

OBJECTIVE: To determine whether nitrite can enhance exercise training (ET) effects in heart failure with preserved ejection fraction (HFpEF). METHODS: In this multicenter, double-blind, placebo-controlled, randomized trial conducted at 1 urban and 9 rural outreach centers between November 22, 2016, and December 9, 2021, patients with HFpEF underwent ET along with inorganic nitrite 40 mg or placebo 3 times daily. The primary end point was peak oxygen consumption (VO2). Secondary end points included Kansas City Cardiomyopathy Questionnaire overall summary score (KCCQ-OSS, range 0 to 100; higher scores reflect better health status), 6-minute walk distance, and actigraphy. RESULTS: Of 92 patients randomized, 73 completed the trial because of protocol modifications necessitated by loss of drug availability. Most patients were older than 65 years (80%), were obese (75%), and lived in rural settings (63%). At baseline, median peak VO2 (14.1 mL·kg-1·min-1) and KCCQ-OSS (63.7) were severely reduced. Exercise training improved peak VO2 (+0.8 mL·kg-1·min-1; 95% CI, 0.3 to 1.2; P<.001) and KCCQ-OSS (+5.5; 95% CI, 2.5 to 8.6; P<.001). Nitrite was well tolerated, but treatment with nitrite did not affect the change in peak VO2 with ET (nitrite effect, -0.13; 95% CI, -1.03 to 0.76; P=.77) or KCCQ-OSS (-1.2; 95% CI, -7.2 to 4.9; P=.71). This pattern was consistent across other secondary outcomes. CONCLUSION: For patients with HFpEF, ET administered for 12 weeks in a predominantly rural setting improved exercise capacity and health status, but compared with placebo, treatment with inorganic nitrite did not enhance the benefit from ET. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02713126.

A Case Report of Mixed-type Dyspnoea Diagnosed via Non-invasive and Invasive Cardiopulmonary Exercise Tests.

A gas exchange analysis with the cardiopulmonary exercise test is effective in discriminating non-cardiogenic components of limited exercise tolerance and is important for use in combination with the diastolic stress test. An 80-year-old woman with progressive exertional dyspnoea, hypertension, and untreated bronchial asthma was diagnosed with heart failure with a preserved ejection fraction by invasive testing. Diuretics were initiated, which resulted in partial symptom improvement. A subsequent non-invasive test revealed a reduced breathing reserve, suggesting exertional dyspnoea complications linked to lung disease. Bronchodilators were administered, which further improved the symptoms.

Contributions of anemia to exercise intolerance in heart failure with preserved ejection fraction-An exercise stress echocardiographic study.

Aims: Anemia is common in patients with heart failure with preserved ejection fraction (HFpEF) and is associated with exercise intolerance. However, there are limited data on how anemia contributes to reduced exercise capacity in patients with HFpEF. We aimed to characterize exercise capacity, cardiovascular and ventilatory reserve, and the oxygen (O2) pathway in anemic patients with HFpEF. Methods: A total of 238 patients with HFpEF and 248 dyspneic patients without HF underwent ergometry exercise stress echocardiography with simultaneous expired gas analysis. Patients with HFpEF were classified into two groups based on the presence of anemia (hemoglobin < 13.0 g/dL in men and < 12.0 g/dL in women). Results: Anemic HFpEF patients (n = 112) had worse nutritional status and renal function, lower iron levels, and greater left ventricular (LV) remodeling and plasma volume expansion than those without anemia (n = 126). Exercise capacity, assessed by peak oxygen consumption, exercise intensity, and exercise duration, was lower in the anemic HFpEF group than in the other groups. Despite a similar cardiac output during exercise, anemic patients with HFpEF demonstrated limitations in arterial O2 delivery, lower arteriovenous O2 content difference, and ventilatory inefficiency (higher minute ventilation vs. carbon dioxide production slope) during peak exercise. Conclusion: Anemic HFpEF patients demonstrated unique pathophysiological features with greater LV remodeling and plasma volume expansion, limitations in arterial O2 delivery and peripheral O2 extraction, and ventilatory inefficiency, which may contribute to reduced exercise capacity. Further studies are needed to develop an optimal approach for treating anemia in patients with HFpEF.