Echo-derived peak cardiac power output-to-left ventricular mass with cardiopulmonary exercise testing predicts outcome in patients with heart failure and depressed systolic function

Lean body mass and the cardiorespiratory phenotype: An ethnic-specific relationship in Hans Chinese women and men

BACKGROUND

Lean body mass (LBM) and the functional capacity of cardiovascular (CV) and respiratory systems constitute a female-specific relationship in European-American individuals. Whether this recent finding be extrapolated to the world's largest ethnic group, that is, Hans Chinese (HC, a population characterized by low LBM), is unknown.

METHODS

Healthy HC adults (n = 144, 50% ♀) closely matched by sex, age and physical activity were included. Total and regional (leg, arm and trunk) LBM and body composition were measured via dual-energy X-ray absorptiometry. Cardiac structure, stiffness, central/peripheral haemodynamics and peak O2 consumption (VO2peak) were assessed via transthoracic echocardiography and pulmonary gas analyses at rest and during exercise up to peak effort. Regression analyses determined the sex-specific relationship of LBM with cardiac and aerobic phenotypes.

RESULTS

Total and regional LBM were lower and body fat percentage higher in women compared with men (P < 0.001). In both sexes, total LBM positively associated with left ventricular (LV) mass and peak volumes (r ≥ 0.33, P ≤ 0.005) and negatively with LV end-systolic and central arterial stiffness (r ≥ -0.34, P ≤ 0.004). Total LBM strongly associated with VO2peak (r ≥ 0.60, P < 0.001) and peak cardiac output (r ≥ 0.40, P < 0.001) in women and men. Among regional LBM, leg LBM prominently associated with the arterio-venous O2 difference at peak exercise in both sexes (r ≥ 0.43, P < 0.001). Adjustment by adiposity or CV risk factors did not modify the results.

CONCLUSIONS

LBM independently determines internal cardiac dimensions, ventricular mass, distensibility and the capacity to deliver and consume O2 in HC adults irrespective of sex.

Determinants of V̇+O2peak Changes After Aerobic Training in Coronary Heart Disease Patients

This study aimed to highlight the ventilatory and circulatory determinants of changes in ˙VO2peak after exercise-based cardiac rehabilitation (ECR) in patients with coronary heart disease (CHD). Eighty-two CHD patients performed, before and after a 3-month ECR, a cardiopulmonary exercise testing (CPET) on a bike with gas exchanges measurements (˙VO2peak, minute ventilation, i. e., ˙VE), and cardiac output (Q˙c). The arteriovenous difference in O2 (C(a-v¯)O2) and the alveolar capillary gradient in O2 (PAi-aO2) were calculated using Fick's laws. Oxygen uptake efficiency slope (OUES) was calculated. A 5.0% cut off was applied for differentiating non- (NR: ˙VO2<0.0%), low (LR: 0.0≤ ∆˙VO2<5.0%), moderate (MR: 5.0≤∆˙VO2 < 10.0%), and high responders (HR: ∆˙VO2≥10.0%) to ECR. A total of 44% of patients were HR (n=36), 20% MR (n=16), 23% LR (n=19), and 13% NR (n=11). For HR, the ˙VO2peak increase (p<0.01) was associated with increases in ˙VE (+12.8±13.0 L/min, p<0.01), (+1.0±0.9 L/min, p<0.01), and C(a-v¯)O2 (+2.3±2.5 mLO2/100 mL, p<0.01). MR patients were characterized by+6.7±19.7 L/min increase in ˙VE (p=0.04) and+0.7±1.0 L/min of Q˙c (p<0.01). ECR induced decreases in ˙VE (p=0.04) and C(a-v¯)O2 (p<0.01) and a Q˙c increase in LR and NR patients (p<0.01). Peripheral and ventilatory responses more than central adaptations could be responsible for the ˙VO2peak change with ECR in CHD patients.

Cardiac power output is associated with adverse outcomes in patients with preserved ejection fraction after transcatheter aortic valve implantation

Aims

Cardiac power output (CPO) measures cardiac performance, and its prognostic significance in heart failure with preserved ejection fraction (EF) has been previously reported. However, the effectiveness of CPO in risk stratification of patients with valvular heart disease and post-operative valvular disease has not been reported. We aimed to determine the association between CPO and clinical outcomes in patients with preserved left ventricular (LV) EF after transcatheter aortic valve implantation (TAVI).

Methods and results

This retrospective observational study included 1047 consecutive patients with severe aortic stenosis after TAVI. All patients were followed up for all-cause mortality and hospitalization for HF. CPO was calculated as 0.222 × cardiac output × mean blood pressure (BP)/LV mass, where 0.222 was the conversion constant to W/100 g of the LV myocardium. CPO was assessed using transthoracic echocardiography at discharge after TAVI. Of the 1047 patients, 253 were excluded following the exclusion criteria, including those with low LVEF, and 794 patients (84.0 [80.0-88.0] years; 35.8% male) were included in this study. During a median follow-up period of 684 (237-1114) days, the composite endpoint occurred in 196 patients. A dose-dependent association was observed between the CPO levels and all-cause mortality. Patients in the lowest CPO tertile had significantly lower event-free survival rates (log-rank test, P = 0.043). Multivariate Cox regression analysis showed that CPO was independently associated with adverse outcomes (hazard ratio = 0.561, P = 0.020). CPO provided an incremental prognostic effect in the model based on clinical and echocardiographic markers (P = 0.034).

Conclusion

CPO is independently and incrementally associated with adverse outcomes in patients with preserved LVEF following TAVI.

Integrative Assessment of Cardiopulmonary Fitness Using Cardiopulmonary Exercise Test With Supine Bicycle Echocardiography in Patients Presenting Dyspnea

BACKGROUND

Cardiopulmonary exercise test (CPET) with supine bicycle echocardiography (SBE) enables comprehensive physiologic assessment during exercise. We characterized cardiopulmonary fitness by integrating CPET-SBE parameters and evaluated its prognostic value in patients presenting with dyspnea.

METHODS AND RESULTS

We retrospectively reviewed 473 consecutive patients who underwent CPET-SBE for dyspnea evaluation. A dimensionality reduction process was applied, transforming 24 clinical and CPET-SBE parameters into a 2-dimensional feature map, followed by patient clustering based on the data distribution. Clinical and exercise features were compared among the clusters in addition to the 5-year risk of clinical outcome (a composite of cardiovascular death and heart failure hospitalization). Maximum exercise effort (R >1) was achieved in 95% of cases. Through dimensionality reduction, 3 patient clusters were derived: Group 1 (n=157), 2 (n=104), and 3 (n=212). Median age and female proportion increased from Group 1 to 2, and 3, although resting echocardiography parameters showed no significant abnormalities among the groups. There was a worsening trend in the exercise response from Group 1 to 2 and 3, including left ventricular diastolic function, oxygen consumption, and ventilatory efficiency. During follow-up (median 6.0 [1.6-10.4] years), clinical outcome increased from Group 1 to 2 and 3 (5-year rate 3.7% versus 7.0% versus 13.0%, respectively; log-rank P=0.02), with higher risk in Group 2 (hazard ratio, 1.94 [95% CI, 0.52-7.22]) and Group 3 (3.92 [1.34-11.42]) compared with Group 1.

CONCLUSIONS

Comprehensive evaluation using CPET-SBE can reveal distinct characteristics of cardiopulmonary fitness in patients presenting with dyspnea, potentially enhancing outcome prediction.

Patient phenotype profiling using echocardiography and natriuretic peptides to personalise heart failure therapy

Heart failure (HF) is a progressive condition with a clinical picture resulting from reduced cardiac output (CO) and/or elevated left ventricular (LV) filling pressures (LVFP). The original Diamond-Forrester classification, based on haemodynamic data reflecting CO and pulmonary congestion, was introduced to grade severity, manage, and risk stratify advanced HF patients, providing evidence that survival progressively worsened for those classified as warm/dry, cold/dry, warm/wet, and cold/wet. Invasive haemodynamic evaluation in critically ill patients has been replaced by non-invasive haemodynamic phenotype profiling using echocardiography. Decreased CO is not infrequent among ambulatory HF patients with reduced ejection fraction, ranging from 23 to 45%. The Diamond-Forrester classification may be used in combination with the evaluation of natriuretic peptides (NPs) in ambulatory HF patients to pursue the goal of early identification of those at high risk of adverse events and personalise therapy to antagonise neurohormonal systems, reduce congestion, and preserve tissue/renal perfusion. The most benefit of the Guideline-directed medical treatment is to be expected in stable patients with the warm/dry profile, who more often respond with LV reverse remodelling, while more selective individualised treatments guided by echocardiography and NPs are necessary for patients with persisting congestion and/or tissue/renal hypoperfusion (cold/dry, warm/wet, and cold/wet phenotypes) to achieve stabilization and to avoid further neurohormonal activation, as a result of inappropriate use of vasodilating or negative chronotropic drugs, thus pursuing the therapeutic objectives. Therefore, tracking the haemodynamic status over time by clinical, imaging, and laboratory indicators helps implement therapy by individualising drug regimens and interventions according to patients' phenotypes even in an ambulatory setting.

Assessing cardiac power output values in a healthy adult population

Cardiac power output (CPO), which combines pressure and flow capacities, directly measures the heart's pumping capability. It is proposed as a superior alternative to ejection fraction in assessing cardiac function. However, there is a lack of data on CPO in healthy individuals, prompting a study to determine the cardiac power output in healthy adults in the Iranian population. This cross-sectional descriptive study investigated cardiac power in a sample of healthy individuals. Participants were recruited from healthy individuals referred to the Echocardiography department using convenience sampling. In this study, we examined the echocardiographic parameters in 173 individuals, of which 52% were men. Men exhibited significantly higher values for stroke volume, cardiac output, and cardiac power output (CPO) in both ventricles, as well as larger body surface area (BSA) and systemic mean arterial pressure (MAP), compared to women. Individuals under the age of 40 had significantly higher BSA and right ventricular cardiac output compared to those aged 40 or above. Multivariate analysis revealed that MAP, left ventricular (LV) cardiac output, LVCPO, pulmonary MAP, right ventricular (RV) CPO, and RV cardiac power index (CPI) were significant predictors of LVCPI changes. Our findings emphasize the importance of cardiac power output as a comprehensive measure of cardiac function, complementing the traditional use of ejection fraction. Further research is warranted to validate these results, establish accurate reference ranges, and explore the clinical implications of cardiac power output in various patient populations.

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.

Contemporary Evidence and Practice on Right Heart Catheterization in Patients with Acute or Chronic Heart Failure

Heart failure (HF) has a global prevalence of 1-2%, and the incidence around the world is growing. The prevalence increases with age, from around 1% for those aged <55 years to >10% for those aged 70 years or over. Based on studies in hospitalized patients, about 50% of patients have heart failure with reduced ejection fraction (HFrEF), and 50% have heart failure with preserved ejection fraction (HFpEF). HF is associated with high morbidity and mortality, and HF-related hospitalizations are common, costly, and impact both quality of life and prognosis. More than 5-10% of patients deteriorate into advanced HF (AdHF) with worse outcomes, up to cardiogenic shock (CS) condition. Right heart catheterization (RHC) is essential to assess hemodynamics in the diagnosis and care of patients with HF. The aim of this article is to review the evidence on RHC in various clinical scenarios of patients with HF.

Heart failure classifications via non-invasive pressure volume loops from echocardiography

BACKGROUND

Left ventricular pressure-volume (LV-PV) loops provide comprehensive characterization of cardiovascular system in both health and disease, which are the essential element of the hemodynamic evaluation of heart failure (HF). This study attempts to achieve more detailed HF classifications by non-invasive LV-PV loops from echocardiography and analyzes contribution of parameters to HF classifications.

METHODS

Firstly, non-invasive PV loops are established by time-varying elastance model where LV volume curves were extracted from apical-four-chambers view of echocardiographic videos. Then, 16 parameters related to cardiac structure and functions are automatically acquired from PV loops. Next, we applied six machine learning (ML) methods to divide four categories. On this premise, we choose the best performing classifier among machine learning approaches for feature ranking. Finally, we compare the contributions of different parameters to HF classifications.

RESULTS

By the experimental, the PV loops were successfully acquired in 1076 cases. When single left ventricular ejection fraction (LVEF) is used for HF classifications, the accuracy of the model is 91.67%. When added parameters extracted from ML-derived LV-PV loops, the classification accuracy is 96.57%, which improved by 5.1%. Especially, our parameters have a great improvement in the classification of non-HF controls and heart failure with preserved ejection fraction (HFpEF).

CONCLUSIONS

We successfully presented the classification of HF by machine derived non-invasive LV-PV loops, which has the potential to improve the diagnosis and management of heart failure in clinic. Moreover, ventriculo-arterial (VA) coupling and ventricular efficiency were demonstrated important factors for ML-based HF classification model besides LVEF.

Age, sex, endurance capacity, and chronic heart failure affect central and peripheral factors of oxygen uptake measured by non-invasive and continuous technologies: support of pioneer work using invasive or non-continuous measures

Introduction

It is known that maximum oxygen uptake depends on age, sex, endurance capacity, and chronic heart failure. However, due to the required invasive or often applied non-continuous approaches, less is known on underlying central and peripheral factors. Thus, this study aimed to investigate the effects of age, sex, endurance capacity, and chronic heart failure on non-invasively and continuously measured central and peripheral factors of oxygen uptake.

Methods

15 male children (11 ± 1 years), 15 male (24 ± 3 years) and 14 female recreationally active adults (23 ± 2 years), 12 male highly trained endurance athletes (24 ± 3 years), and 10 male elders (59 ± 6 years) and 10 chronic heart failure patients (62 ± 7 years) were tested during a cardiopulmonary exercise test on a cycling ergometer until exhaustion for: blood pressure, heart rate, stroke volume, cardiac output, cardiac power output, vastus lateralis muscle oxygen saturation, and (calculated) arterio-venous oxygen difference. For the non-invasive and continuous measurement of stroke volume and muscle oxygen saturation, bioreactance analysis and near-infrared spectroscopy were used, respectively. A two-factor repeated measure ANOVA and partial eta-squared effect sizes (η p 2 ) were applied for statistical analyses at rest, 80, and 100% of oxygen uptake.

Results

For the age effect, there were statistically significant group differences for all factors (p ≤ .033; η p 2 ≥ .169 ). Concerning sex, there were group differences for all factors (p ≤ .010; η p 2 ≥ .223 ), except diastolic blood pressure and heart rate (p ≥ .698; η p 2 ≤ .006 ). For the effect of endurance capacity, there were no group differences for any of the factors (p ≥ .065; η p 2 ≤ .129 ). Regarding chronic heart failure, there were group differences for the heart rate and arterio-venous oxygen difference (p ≤ .037; η p 2 ≥ .220 ).

Discussion

Age, sex, endurance capacity, and chronic heart failure affect central and peripheral factors of oxygen uptake measured by non-invasive and continuous technologies. Since most of our findings support pioneer work using invasive or non-continuous measures, the validity of our applied technologies is indirectly confirmed. Our outcomes allow direct comparison between different groups serving as reference data and framework for subsequent studies in sport science and medicine aiming to optimise diagnostics and interventions in athletes and patients.

Deep phenotype characterization of hypertensive response to exercise: implications on functional capacity and prognosis across the heart failure spectrum

AIMS

Limited evidence is available regarding the role of hypertensive response to exercise (HRE) in heart failure (HF). We evaluated the systolic blood pressure (SBP) to workload slope during exercise across the HF spectrum, investigating haemodynamic and prognostic correlates of HRE.

METHODS AND RESULTS

We prospectively enrolled 369 patients with HF Stage C (143 had preserved [HFpEF], and 226 reduced [HFrEF] ejection fraction), 201 subjects at risk of developing HF (HF Stages A-B), and 58 healthy controls. We performed a combined cardiopulmonary exercise stress echocardiography testing. We defined HRE as the highest sex-specific SBP/workload slope tertile in each HF stage. Median SBP/workload slope was 0.53 mmHg/W (interquartile range 0.36-0.72); the slope was 39% steeper in women than men (p < 0.0001). After adjusting for age and sex, SBP/workload slope in HFrEF (0.47, 0.30-0.63) was similar to controls (0.43, 0.35-0.57) but significantly lower than Stages A-B (0.61, 0.47-0.75) and HFpEF (0.63, 0.42-0.86). Patients with HRE showed significantly lower peak oxygen consumption and peripheral oxygen extraction. After a median follow-up of 16 months, HRE was independently associated with adverse outcomes (all-cause mortality and hospitalization for cardiovascular reasons: hazard ratio 2.05, 95% confidence interval 1.81-5.18), while rest and peak SBP were not. Kaplan-Meier analysis confirmed a worse survival probability in Stages A-B (p = 0.005) and HFpEF (p < 0.001), but not HFrEF.

CONCLUSION

A steeper SBP/workload slope is associated with impaired functional capacity across the HF spectrum and could be a more sensitive predictor of adverse events than absolute SBP values, mainly in patients in Stages A-B and HFpEF.

Impact of training on combined cardiopulmonary exercise test with stress echocardiography parameters in HFrEF patients

BACKGROUND

Exercise-based cardiac rehabilitation is recognized to improve quality of life in heart failure patients. However, the effects on the cardiac function are understudied. The main objective was to assess the impact of a 4-week cardiac rehabilitation program on cardiopulmonary exercise testing (CPET) combined with simultaneous echocardiography parameters in chronic heart failure (CHF) patients. The secondary aim was to investigate patients' responses to training.

METHODS

Forty-one CHF patients with reduced ejection fraction (29.3 ± 0.1%) underwent CPET and stress echocardiography before and after a 4-week of exercise-training program. Blood parameters, echocardiography and cardiopulmonary parameters were assessed before and after training. Potential echocardiography derived predictive parameters like left and right contractile reserves, left ventricle elastance, end systolic volume and right ventricle S wave response to exercise were also assessed.

RESULTS

The training program increased the peak oxygen consumption (VO₂) (P < 0.001), the peak systolic blood pressure, the left ventricular outflow tract velocity time integral (P < 0.05) and the circulatory (P < 0.001) and ventilatory (P < 0.01) powers. It also decreased the VE/VCO₂ slope (P < 0.001). As the median value of peak VO₂ gain was 17%, patients above this value were considered as responders and patients below as non-responders to training. The responders presented a higher left ventricle contractile reserve compared to non-responder patients. The peak left ventricle elastance and peak right ventricle S wave response tended to be higher in responders.

CONCLUSION

Combination of CPET and stress echocardiography may contribute to establish the disease severity stratification and to predict response to training in CHF patients with reduced ejection fraction.

Sex differences in left ventricular stroke work and cardiac power output per unit myocardium relate to blood pressure in apparently healthy adults

BACKGROUND

Left ventricular stroke work per unit myocardium (LVSWM) and cardiac power output per unit myocardium (CPOM) are important measures of myocardial workload. The sex differences in the myocardial workload and its correlation with blood pressure remain largely unclear.

OBJECTIVES

The purpose of this study is to investigate the sex differences in LVSWM and CPOM, and to relate them to blood pressure in a cohort of apparently healthy adults.

METHODS

The LVSWM and CPOM were estimated in 596 age- and heart rate-matched apparently healthy adults (298 men) using transthoracic echocardiography combined with cuff-measured brachial blood pressure. The data were compared between sexes, and the sex differences in LVSWM and CPOM were related to blood pressure.

RESULTS

After adjustment for the blood pressure, the LVSWM and CPOM were higher in women than in men [75.0 (73.7-76.4) vs 64.9 (63.5-66.2) cJ/100g for LVSWM, and 912.4 (894.1-930.6) vs 780.2 (762.0-798.5) milliwatt/100g for CPOM, respectively; all P<0.001]. After adjustment for the LVSWM and CPOM, the mean systolic and diastolic blood pressure were 7.4 mm Hg and 5.2 mm Hg higher in men than in women, respectively (all P<0.001).

CONCLUSIONS

For any given blood pressure, the workload per unit myocardium is higher in apparently healthy women than in their male counterparts. A sex-specific definition of normal blood pressure with a relatively lower threshold for women can minimize the sex differences in the myocardial workload, which might reduce the potentially comparatively higher risk of heart failure in women.

Utility of Cardiac Power Hemodynamic Measurements in the Evaluation and Risk Stratification of Cardiovascular Conditions

Despite numerous advancements in prevention, diagnosis and treatment, cardiovascular disease has remained the leading cause of mortality globally for the past 20 years. Part of the explanation for this trend is persistent difficulty in determining the severity of cardiac conditions in order to allow for the deployment of prompt therapies. This review seeks to determine the prognostic importance of cardiac power (CP) measurements, including cardiac power output (CPO) and cardiac power index (CPI), in various cardiac pathologies. CP was evaluated across respective disease-state categories which include cardiogenic shock (CS), septic shock, transcatheter aortic valve replacement (TAVR), heart failure (HF), post-myocardial infarction (MI), critical cardiac illness (CCI) and an "other" category. Literature review was undertaken of articles discussing CP in various conditions and this review found utility and prognostic significance in the evaluation of TAVR patients with a significant correlation between one-year mortality and CPI; in HF patients showing CPI and CPO as valuable tools to assess cardiac function in the acute setting; and, additionally, CPO was found to be an essential tool in patients with CCI, as the literature showed that CPO was statistically correlated with mortality. Cardiac power and the derived measures obtained from this relatively easily obtained variable can allow for essential estimations of prognostic outcomes in cardiac patients.

A Holistic View of Advanced Heart Failure

Advanced heart failure (HF) may occur at any level of left ventricular (LV) ejection fraction (LVEF). The latter, which is widely utilized for the evaluation of LV systolic performance and treatment guidance of HF patients, is heavily influenced by LV size and geometry. As the accurate evaluation of ventricular systolic function and size is crucial in patients with advanced HF, the LVEF should be supplemented or even replaced by more specific indices of LV function such as the systolic strain and cardiac power output and size such as the LV diastolic diameters and volumes. Conventional treatment (cause eradication, medications, devices) is often poorly tolerated and fails and advanced treatment (mechanical circulatory support [MCS], heart transplantation [HTx]) is required. The effectiveness of MCS is heavily dependent on heart size, whereas HTx which is effective in the vast majority of the cases is limited by the small donor pool. Expanding the MCS indications to include patients with small ventricles as well as the HTx donor pool are major challenges in the management of advanced HF.

Prognostic significance of resting cardiac power to left ventricular mass and E/e’ ratio in heart failure with preserved ejection fraction

Background

Cardiac power-to-left ventricular mass (power/mass) is an index reflecting the muscular hydraulic pump capability of the heart, and the E/e’ ratio is a specific indicator for identifying increased left ventricular filling pressure. Limited data exist regarding the prognostic value of incorporating power/mass and E/e’ ratio in heart failure with preserved ejection fraction (HFpEF).

Materials and methods

In total, 475 patients with HFpEF from the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial with complete baseline echocardiography data were included in our analysis. Patients were categorized into four groups according to power/mass and E/e’ ratio. The risk of outcomes was examined using Cox proportional hazards models and competing risk models.

Results

Patients with low power/mass and high E/e’ were more likely to be males (60.5%), with higher waist circumference, and had a higher prevalence of diabetes (52.1%), atrial fibrillation (50.4%), and lower estimated glomerular filtration rate (eGFR). Combined resting power/mass and E/e’ have graded correlations with left ventricular (LV) dysfunction and clinical outcomes in patients with HFpEF. After multivariable adjustments, an integrative approach combining power/mass and E/e’ remained to be a powerful prognostic predictor, with the highest HRs of clinical outcomes observed in patients with low power/mass and high E/e’ (all-cause mortality: HR 3.45; 95% CI: 1.69–7.05; P = 0.001; hospitalization for heart failure: HR 3.27; 95% CI: 1.60–6.67; P = 0.001; and primary endpoint: HR 3.07; 95% CI: 1.73–5.42; P &lt; 0.001).

Conclusion

In patients with HFpEF, an echo-derived integrated approach incorporating resting power/mass and E/e’ ratio remained to be a powerful prognosis predictor and may be useful to risk-stratify patients with this heterogeneous syndrome.

Clinical Trial Registration

[https://clinicaltrials.gov], identifier [NCT00094302].

Prognostic Role of Cardiac Power in a Large Cohort of Patients with Normal Ejection Fraction Referred for Dobutamine Stress Echocardiography

BACKGROUND

Cardiac power reflects cardiac performance in terms of energy transferred by the left ventricle (LV) to the aorta per unit time. Peak stress cardiac power has been shown to predict outcome in patients with reduced LV ejection fraction (EF), and more recently, in patients with normal EF referred for exercise stress echocardiography. We sought to evaluate the prognostic significance of cardiac power in patients with normal EF referred for dobutamine stress test (DSE).

METHODS

We studied data from 15,576 patients with EF ≥50% and no significant valvular or right ventricular dysfunction, undergoing DSE. Cardiac power at rest and peak stress and power reserve (peak stress minus rest power) were calculated and normalized to LV mass. Outcome endpoints were all-cause mortality and new-onset heart failure (HF).

RESULTS

The mean age was 66±13 years and 49% patients were females. Resting and peak stress power/mass were 0.7±0.2 and 1.6±0.6 W/100 g of LV myocardium, respectively. During follow-up [median 3.3 (IQR 0.7-7.3) years], 2,278 patients died and 2,137 developed HF. After adjusting for age, sex, comorbidities, and stress test results, lower peak stress power/mass was independently associated with mortality [adjusted hazard ratio (HR), highest vs. lowest quartile, 0.84, 95% confidence intervals (CI) 0.74-0.95, P=0.004] and HF at follow-up [adjusted HR 0.67, 95% CI 0.59-0.76, P<0.0001]. Power reserve showed similar associations with outcomes.

CONCLUSION

Assessment of cardiac power during DSE in patients with normal EF provides valuable prognostic information regarding risk of mortality and future HF, in addition to stress test results. It is an important research tool to study cardiac performance and development of risk scores incorporating this novel index could be considered after further validation in prospective studies.

Resting Cardiac Power Predicts Adverse Outcome in Heart Failure Patients With Preserved Ejection Fraction: A Prospective Study

Background

We sought to explore the significance of resting cardiac power/mass in predicting adverse outcome in patients with heart failure with preserved ejection fraction (HFpEF).

Methods

This prospective cohort study included patients with HFpEF and without significant valve disease or right ventricular dysfunction. Cardiac power was normalized to left ventricular (LV) mass and expressed in W/100 g of LV myocardium. Multivariate Cox regression analysis was used to evaluate the association between resting cardiac power/mass and composite endpoint, which included all-cause mortality and heart failure (HF) hospitalization.

Results

A total of 2,089 patients were included in this study. After an average follow-up of 4.4 years, 612 (29.30%) patients had composite endpoint, in which 331 (15.84%) died and 391 (18.72%) experienced HF hospitalization. In multivariate Cox regression analysis, resting power/mass < 0.7 W/m² was independently associated with composite endpoint, all-cause mortality, cardiovascular mortality and HF hospitalization, with hazard ratios (HR) of 1.309 [95% confidence interval (CI): 1.108–1.546, P = 0.002], 1.697 (95%CI: 1.344–2.143, P < 0.001), 2.513 (95%CI: 1.711–3.689, P < 0.001), and 1.294 (95%CI: 1.052–1.592, P = 0.015), respectively. For composite endpoint, cardiovascular mortality and HF hospitalization, the C statistic increased significantly when incorporating resting cardiac power/mass into a model with established risk factors. For composite endpoint, the continuous net reclassification index after adding resting cardiac power/mass in the original model with N-terminal pro-brain natriuretic peptide was 13.1% (95%CI: 2.9–21.6%, P = 0.007), and the integrated discrimination index was 1.9% (95%CI: 0.8–3.2%, P < 0.001).

Conclusion

Resting cardiac power determined by non-invasive echocardiography is independently associated with the risk of adverse outcomes in HFpEF patients and provides incremental prognostic information.

Improved diastolic dysfunction is associated with higher forward flow and better prognosis in chronic heart failure

The benefit of repeat assessment of left ventricular (LV) systolic and diastolic function in heart failure (HF) remains uncertain. We assessed the prognostic value of repeat echocardiographic assessment of LV filling pressure (LVFP) and its interaction with cardiac index (CI) in ambulatory patients with chronic HF and reduced ejection fraction (HFrEF). We enrolled 357 patients (age 68 ± 11 years; 22% female) with chronic HFrEF. Patients underwent a clinical and echocardiographic examination at baseline. LVFP as assessed by the 2016 Guidelines and Doppler-derived CI were estimated. After the second echocardiographic examination, patients were followed for a median time of 30 months. The study endpoint included all-cause death and hospitalization for worsening HF. Patients who normalized LVFP or showed persistently normal LVFP at the follow-up examination had a significantly lower mortality rate than those with worsening or persistently raised LVFP (p < 0.0001). After stratification by CI, patients with elevated LVFP and CI < 2.0 l/min/m2 had a further worse outcome than those with elevated LVFP and CI ≥ 2.0 l/min/m2 (p < 0.0001). Multivariate survival analysis confirmed an independent prognostic impact of changes in LVFP, incremental to that of established clinical, laboratory and echocardiographic predictors. Repeat assessment of LVFP and CI significantly improved risk stratification of chronic HFrEF outpatients compared to baseline evaluation.

Noninvasive echocardiographic cardiac power output predicts mortality in cardiac intensive care unit patients

BACKGROUND

Low cardiac power output (CPO), measured invasively, can identify critically ill patients at increased risk of adverse outcomes, including mortality. We sought to determine whether non-invasive, echocardiographic CPO measurement was associated with mortality in cardiac intensive care unit (CICU) patients.

METHODS

Patients admitted to CICU between 2007 and 2018 with echocardiography performed within one day (before or after) admission and who had available data necessary for calculation of CPO were evaluated. Multivariable logistic regression determined the relationship between CPO and adjusted hospital mortality.

RESULTS

A total of 5,585 patients (age of 68.3 ± 14.8 years, 36.7% female) were evaluated with admission diagnoses including acute coronary syndrome (ACS) in 56.7%, heart failure (HF) in 50.1%, cardiac arrest (CA) in 12.2%, shock in 15.5%, and cardiogenic shock (CS) in 12.8%. The mean left ventricular ejection fraction (LVEF) was 47.3 ± 16.2%, and the mean CPO was 1.04 ± 0.37 W. There were 419 in-hospital deaths (7.5%). CPO was inversely associated with the risk of hospital mortality, an association that was consistent among patients with ACS, HF, and CS. On multivariable analysis, higher CPO was associated with reduced hospital mortality (OR 0.960 per 0.1 W, 95CI 0.0.926-0.996, P = .03). Hospital mortality was particularly high in patients with low CPO coupled with reduced LVEF, increased vasopressor requirements, or higher admission lactate.

CONCLUSIONS

Echocardiographic CPO was inversely associated with hospital mortality in unselected CICU patients, particularly among patients with increased lactate and vasopressor requirements. Routine calculation and reporting of CPO should be considered for echocardiograms performed in CICU patients.

Real-time exercise reduces impaired cardiac function in breast cancer patients undergoing chemotherapy: A randomized controlled trial

BACKGROUND

Previous studies have reported that chemotherapy results in substantial long-term risk of heart failure. Exercise ameliorates exercise responses and exercise tolerance in patients receiving chemotherapy. The cardioprotective effect of real-time exercise in breast cancer is still unclear.

OBJECTIVES

The aim of the present study was to determine the effect of real-time moderate-to-high-intensity exercise training in women with breast cancer undergoing chemotherapy and to follow up on parameters of cardiac function and exercise capacity at different times. We hypothesized that early moderate-to-high-intensity exercise training has beneficial effects on cardiac function in women with breast cancer undergoing chemotherapy.

METHODS

This was a randomized controlled study that included 32 women randomly allocated into the control or exercise group. Exercise began with the first cycle of chemotherapy, and the training program was maintained during chemotherapy with 2 to 3 sessions per week for 3 months. Patients were instructed to perform moderate-to-high-intensity training with aerobic and resistance training. Outcome measurements were echocardiography and cardiopulmonary exercise test. The primary outcome was the change in left ventricle ejection fraction (LVEF). The secondary outcome was peak oxygen consumption (peak VO2).

RESULTS

The control group showed lower cardiac systolic function than the exercise group [mean (SD) LVEF 62% (2) and 70% (5), P<0.05], reduced cardiac diastolic function, and cardiac hypertrophy at 3, 6 and 12 months after chemotherapy. At 6 months after chemotherapy, the exercise group exhibited relatively higher exercise capacity than controls [mean (SD) VO2 12.1 (2.2) and 13.6 (2.2) mL/kg/min, P<0.05]. The main effect size of the study based on echocardiography outcomes was 0.25 (95% confidence interval 0.23 to 0.27), a medium effect size.

CONCLUSIONS

Moderate-to-high-intensity exercise training in breast cancer patients undergoing chemotherapy may prevent impaired cardiac function.

CLINICAL TRIAL REGISTRATION

https://www.

CLINICALTRIALS

in.th (Identifier TCTR20190330002).

Arterial Hypertension and Cardiopulmonary Function: The Value of a Combined Cardiopulmonary and Echocardiography Stress Test

Arterial hypertension (AH) is a global burden and the leading risk factor for mortality worldwide. Haemodynamic abnormalities, longstanding neurohormonal and inflammatory activation, which are commonly observed in patients with AH, promote cardiac structural remodeling ultimately leading to heart failure (HF) if blood pressure values remain uncontrolled. While several epidemiological studies have confirmed the strong link between AH and HF, the pathophysiological processes underlying this transition remain largely unclear. The combined cardiopulmonary-echocardiography stress test (CPET-ESE) represents a precious non-invasive aid to detect alterations in patients at the earliest stages of HF. The opportunity to study the response of the cardiovascular system to exercise, and to differentiate central from peripheral cardiovascular maladaptations, makes the CPET-ESE an ideal technique to gain insights into the mechanisms involved in the transition from AH to HF, by recognizing alterations that might be silent at rest but influence the response to exercise. Identifications of these subclinical alterations might allow for a better risk stratification in hypertensive patients, facilitating the recognition of those at higher risk of evolution towards established HF. This may also lead to the development of novel preventive strategies and help tailor medical treatment. The purpose of this review is to summarise the potential advantages of using CPET-ESE in the characterisation of hypertensive patients in the cardiovascular continuum.

Overcoming the Limits of Ejection Fraction and Ventricular-Arterial Coupling in Heart Failure

Left ventricular ejection fraction (LVEF) and ventricular-arterial coupling (VAC) [VAC = Ea/Ees; Ea: effective arterial elastance; Ees: left ventricle (LV) elastance] are both dimensionless ratios with important limitations, especially in heart failure setting. The LVEF to VAC relationship is a divergent non-linear function, having a point of intersection at the specific value of 0.62, where V0 = 0 ml (V0: the theoretical extrapolated value of the volume-axis intercept at end-systolic pressure 0 mmHg). For the dilated LV, both LVEF and VAC are highly dependent on V0 which is inconclusive when derived from single-beat Ees formulas. VAC simplification should be avoided. Revisiting the relationship between systolic time intervals (STI), pressure, and volumes could provide simple-to-use guiding formulas, affordable for daily clinical practice. We have analyzed by echocardiography the hemodynamics of 21 patients with severe symptomatic heart failure with reduced ejection (HFrEF) compared to 12 asymptomatic patients (at risk of heart failure with mild structural disease). The groups were unequivocally separated by ‘classic’ measures (LVEF, LV end-systolic volume (ESV), LV mass, STI). Chen's Ees formula was weakly correlated with LVEF and indexed ESV (ESVi) but better correlated to the pre-ejection period (PEP); PEP/total ejection time (PEP/TET); systolic blood pressure/PEP (SBP/PEP) (P < 0.001). Combining the predictability of the LVEF to the determinant role of SBP/PEP on the Ees variations, we obtained: (SBP^*LVEF)/PEP mm Hg/ms, with an improved R² value (R² = 0.848; P < 0.001). The strongest correlations to VAC were for LVEF (R = −0.849; R² = 0.722) and PEP/TET (R = 0.925; R² = 0.857). By multiple regression, the VAC was strongly predicted (N = 33): (R = 0.975; R² = 0.95): VAC = 0.553–0.009^*LVEF + 3.463^*PEP/TET, and natural logarithm: Ln (VAC) = 0.147–1.4563^*DBP/SBP^*0.9–0.010^*LVEF + 4.207^*PEP/TET (R = 0.987; R² = 0.975; P = 0) demonstrating its exclusive determinants: LVEF, PEP/TET, and DBP/SBP. Considering Ea as a known value, the VAC-derived Ees formula: Ees_d ≈ Ea/(0.553–0.009^*LVEF+3.463^*PEP/TET) was strongly correlated to Chen's Ees formula (R = 0.973; R² = 0.947) being based on SBP, ESV, LVEF, and PEP/TET and no exponential power. Thus, the new index supports our hypothesis, in the limited sample of patients with HFrEF. Indices like SBP/PEP, (SBP^*LVEF)/PEP, PEP/TET, and DBP/SBP deserve further experiments, underlining the major role of the forgotten STI.

Impact of diabetes on cardiopulmonary function: the added value of a combined cardiopulmonary and echocardiography stress test

Type 2 diabetes mellitus (T2DM) represents a major health issue worldwide, as patients with T2DM show an excess risk of death for cardiovascular causes, twice as high as the general population. Among the many complications of T2DM, heart failure (HF) deserves special consideration as one of the leading causes of morbidity and reduced life expectancy. T2DM has been associated with different phenotypes of HF, including HF with reduced and preserved ejection fraction. Cardiopulmonary exercise testing (CPET) can evaluate the metabolic and ventilatory alterations related to myocardial dysfunction and/or peripheral impairment, representing a unique tool for the clinician to study the whole HF spectrum. While CPET allows for a thorough evaluation of functional capacity, it cannot directly differentiate central and peripheral determinants of effort intolerance. Combining CPET with imaging techniques could provide even higher accuracy and further insights into the progression of the disease since signs of left ventricular systolic and diastolic dysfunction can be detected during exercise, even in asymptomatic diabetic individuals. This review aims to dissect the alterations in cardiopulmonary function characterising patients with T2DM and HF to improve patient risk stratification.

Mechanisms of reduced peak oxygen consumption in subjects with uncomplicated type 2 diabetes

Background

Type 2 diabetes mellitus (T2D) increases the risk of incident heart failure (HF), whose earliest fingerprint is effort intolerance (i.e. impaired peak oxygen consumption, or VO_2peak). In the uncomplicated T2D population, however, the prevalence of effort intolerance and the underpinning mechanistic bases are uncertain. Leveraging the multiparametric characterization allowed by imaging-cardiopulmonary exercise testing (iCPET), the aim of this study is to quantify effort intolerance in T2D and to dissect the associated cardiopulmonary alterations.

Methods

Eighty-eight adults with well-controlled and uncomplicated T2D and no criteria for HF underwent a maximal iCPET with speckle tracking echocardiography, vascular and endothelial function assessment, as well as a comprehensive biohumoral characterization. Effort intolerance was defined by a VO_2peak below 80% of maximal predicted oxygen uptake.

Results

Forty-eight patients (55%) had effort intolerance reaching a lower VO_2peak than T2D controls (16.5 ± 3.2 mL/min/kg, vs 21.7 ± 5.4 mL/min/kg, p < 0.0001). Despite a comparable cardiac output, patients with effort intolerance showed reduced peak peripheral oxygen extraction (11.3 ± 3.1 vs 12.7 ± 3.3 mL/dL, p = 0.002), lower VO₂/work slope (9.9 ± 1.2 vs 11.2 ± 1.4, p < 0.0001), impaired left ventricle systolic reserve (peak S’ 13.5 ± 2.8 vs 15.2 ± 3.0, p = 0.009) and global longitudinal strain (peak-rest ΔGLS 1.7 ± 1.5 vs 2.5 ± 1.8, p = 0.03) than subjects with VO_2peak above 80%. Diastolic function, vascular resistance, endothelial function, biohumoral exams, right heart and pulmonary function indices did not differ between the two groups.

Conclusions

Effort intolerance and reduced VO_2peak is a severe and highly prevalent condition in uncomplicated, otherwise asymptomatic T2D. It results from a major defect in skeletal muscle oxygen extraction coupled with a subtle myocardial systolic dysfunction.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01314-6.

Characterisation of haemodynamic and metabolic abnormalities in the heart failure spectrum: the role of combined cardiopulmonary and exercise echocardiography stress test

Heart failure (HF) is a complex clinical syndrome characterised by different etiologies and a broad spectrum of cardiac structural and functional abnormalities. Current guidelines suggest a classification based on left ventricular ejection fraction (LVEF), distinguishing HF with reduced (HFrEF) from preserved (HFpEF) LVEF. HF should also be thought of as a continuous range of conditions, from asymptomatic stages to clinically manifest syndrome. The transition from one stage to the next is associated with a worse prognosis. While the rate of HF-related hospitalisation is similar in HFrEF and HFpEF once clinical manifestations occur, accurate knowledge of the steps and risk factors leading to HF progression is still lacking, especially in HFpEF. Precise hemodynamic and metabolic characterisation of patients with or at risk of HF may help identify different disease trajectories and risk factors, with the potential to identify specific treatment targets that might offset the slippery slope towards overt clinical manifestations. Exercise can unravel early metabolic and haemodynamic alterations that might be silent at rest, potentially leading to improved risk stratification and more effective treatment strategies. Cardiopulmonary exercise testing (CPET) offers valuable aid to investigate functional alterations in subjects with or at risk of HF, while echocardiography can assess cardiac structure and function objectively, both at rest and during exercise (exercise stress echocardiography, ESE). The purpose of this narrative review is to summarise the potential advantages of using an integrated CPET-ESE evaluation in the characterisation of both subjects at risk of developing HF and patients with stable HF.

Prognostic value of peak stress cardiac power in patients with normal ejection fraction undergoing exercise stress echocardiography

AIMS

Cardiac power is a measure of cardiac performance that incorporates both pressure and flow components. Prior studies have shown that cardiac power predicts outcomes in patients with reduced left ventricular (LV) ejection fraction (EF). We sought to evaluate the prognostic significance of peak exercise cardiac power and power reserve in patients with normal EF.

METHODS AND RESULTS

We performed a retrospective analysis in 24 885 patients (age 59 ± 13 years, 45% females) with EF ≥50% and no significant valve disease or right ventricular dysfunction, undergoing exercise stress echocardiography between 2004 and 2018. Cardiac power and power reserve (developed power with stress) were normalized to LV mass and expressed in W/100 g of LV myocardium. Endpoints at follow-up were all-cause mortality and diagnosis of heart failure (HF). Patients in the higher quartiles of power/mass (rest, peak stress, and power reserve) were younger and had higher peak blood pressure and heart rate, lower LV mass, and lower prevalence of comorbidities. During follow-up [median 3.9 (0.6-8.3) years], 929 patients died. After adjusting for age, sex, metabolic equivalents (METs) achieved, ischaemia/infarction on stress test results, medication, and comorbidities, peak stress power/mass was independently associated with mortality [adjusted hazard ratio (HR), highest vs. lowest quartile, 0.5, 95% confidence interval (CI) 0.4-0.6, P < 0.001] and HF at follow-up [adjusted HR, highest vs. lowest quartile, 0.4, 95% CI (0.3, 0.5), P < 0.001]. Power reserve showed similar results.

CONCLUSION

The assessment of cardiac power during exercise stress echocardiography in patients with normal EF provides valuable prognostic information, in addition to stress test findings on inducible myocardial ischaemia and exercise capacity.

Prognostic value of resting cardiac power index depends on mean arterial pressure in dilated cardiomyopathy

AIMS

In recent decades, haemodynamic parameters have been estimated for risk stratification and determining treatment strategies for patients with non-ischaemic dilated cardiomyopathy (DCM). In various invasive procedures, the cardiac pumping capability is defined as cardiac power output (CPO), which is calculated by multiplying cardiac output by the mean arterial pressure. Lower CPO values in advanced heart failure predict adverse outcomes. However, few studies discuss the prognostic value of CPO in mild-to-moderate phase patients. This study aimed to determine the value of the cardiac power index (CPI) obtained from the resting CPO for predicting the prognosis of patients with New York Heart Association Functional Class II or III DCM.

METHODS AND RESULTS

From March 2000 to January 2020, a total of 623 cardiomyopathy patients were evaluated for haemodynamic parameters. Patients with secondary cardiomyopathy, ischaemic cardiomyopathy, valvular heart disease, and Class IV cardiomyopathy were excluded. A total of 176 DCM patients fulfilled the criteria for inclusion. Patients were 51.7 ± 12.5 years old (mean ± standard deviation) with a mean left ventricular ejection fraction of 32.1 ± 9.2%. The patients were divided into two groups by their median CPI (CPI < 0.52, low-CPI; CPI ≥ 0.52, high-CPI). No significant differences were found in the left ventricular end-diastolic diameter, left ventricular ejection fraction, or pulmonary arterial wedge pressure between the groups. The probability of cardiac event-free survival was significantly lower for low-CPI than for high-CPI groups by Kaplan-Meier analysis (P = 0.012), even with no significant difference between the high and low cardiac index groups (P = 0.069). Furthermore, Cox proportional hazards regression analysis revealed that, in addition to the CPI, the systolic and mean arterial pressure involved in CPI calculation were independent predictors of cardiac events. Indeed, among these factors, mean arterial pressure had the strongest prognostic ability.

CONCLUSIONS

Although CPI is effective for stratifying DCM and predicting cardiac events in patients with Class II/III DCM, this prognostic value depends on mean arterial pressure.

Predicting the transition to and progression of heart failure with preserved ejection fraction: a weighted risk score using bio-humoural, cardiopulmonary, and echocardiographic stress testing

AIMS 

Risk stratification of heart failure (HF) patients with preserved ejection fraction (HFpEF) can promote a more personalized treatment. We tested the prognostic value of a multi-parametric evaluation, including biomarkers, cardiopulmonary exercise testing-exercise stress echocardiography (CPET-ESE), and lung ultrasound, in HFpEF patients and subjects at risk of developing HF (HF Stages A and B).

BACKGROUND 

Risk stratification of heart failure (HF) patients with preserved ejection fraction (HFpEF) can promote a more personalized treatment.

DESIGN 

We tested the prognostic value of a multi-parametric evaluation, including biomarkers, cardiopulmonary exercise testing-exercise stress echocardiography (CPET-ESE), and lung ultrasound, in HFpEF patients and subjects at risk of developing HF (HF Stages A and B).

METHODS AND RESULTS 

We performed a resting clinical/bio-humoural evaluation and a symptom-limited CPET-ESE in 274 patients (45 Stage A, 68 Stage B, and 161 Stage C-HFpEF) and 30 age- and sex-matched healthy controls. During a median follow-up of 18.5 months, we reported 71 HF hospitalizations and 10 cardiovascular deaths. Cox proportional-hazards regression identified five independent predictors and each was assigned a number of points proportional to its regression coefficient: stress-rest ΔB-lines >10 (3 points), peak oxygen consumption <16 mL/kg/min (2 points), minute ventilation/carbon dioxide production slope ≥36 (2 points), peak systolic pulmonary artery pressure ≥50 mmHg (1 point) and resting N-terminal pro-brain natriuretic peptide (NT-proBNP) >900 pg/mL (1 point). The event-free survival probability for low risk (<3 points), intermediate risk (3-6 points), and high risk (>6 points) were 93%, 52%, and 20%, respectively. The area under the curve (AUC) for the scoring system to predict events was 0.92 (95% CI 0.88-0.96), with an accuracy significantly higher than the individual components of the score (all P < 0.01 vs. individual AUCs).

CONCLUSION 

A weighted risk score including NT-proBNP, markers of cardiopulmonary dysfunction and indices of exercise-induced pulmonary congestion identifies HFpEF patients at increased risk for adverse events and Stage A and B subjects more likely to progress towards more advanced HF stages.

The year 2019 in the European Heart Journal-Cardiovascular Imaging: Part I

The European Heart Journal-Cardiovascular Imaging was launched in 2012 and has during these years become one of the leading multimodality cardiovascular imaging journals. The journal is now established as one of the top cardiovascular journals and is the most important cardiovascular imaging journal in Europe. The most important studies published in our Journal in 2019 will be highlighted in two reports. Part I of the review will focus on studies about myocardial function and risk prediction, myocardial ischaemia, and emerging techniques in cardiovascular imaging, while Part II will focus on valvular heart disease, heart failure, cardiomyopathies, and congenital heart disease.

Cardiac Reserve and Exercise Capacity: Insights from Combined Cardiopulmonary and Exercise Echocardiography Stress Testing

BACKGROUND

Cardiopulmonary exercise testing (CPET) represents the gold standard to estimate peak oxygen consumption (VO₂) noninvasively. To improve the analysis of the mechanisms behind effort intolerance, we examined whether exercise stress echocardiography measurements relate to directly measured peak VO₂ during exercise in a large cohort of patients within the heart failure (HF) spectrum.

METHODS

We performed a symptom-limited graded ramp bicycle CPET exercise stress echocardiography in 30 healthy controls and 357 patients: 113 at risk of developing HF (American College of Cardiology/American Heart Association stage A-B) and 244 in HF stage C with preserved (HFpEF, n = 101) or reduced ejection fraction (HFrEF, n = 143).

RESULTS

Peak VO₂ significantly decreased from controls (23, 21.7-29.7 mL/kg/minute; median, interquartile range) to stage A-B (18, 15.4-20.7 mL/kg/minute) and stage C (HFpEF: 13.6, 11.8-16.8 mL/kg/minute; HFrEF: 14.2, 10.7-17.5 mL/kg/minute). A regression model to predict peak VO₂ revealed that peak left ventricular (LV) systolic annulus tissue velocity (S'), peak tricuspid annular plane systolic excursion/systolic pulmonary artery pressure (right ventricle-pulmonary artery coupling), and low-load left atrial (LA) reservoir strain/E/e' (LA compliance) were independent predictors, in addition to peak heart rate, stroke volume, and workload (adjusted R² = 0.76, P < .0001). The model was successfully tested in subjects with atrial fibrillation (n = 49) and with (n = 224) and without (n = 163) beta-blockers (all P < .01). Peak S' showed the highest accuracy in predicting peak VO₂ < 10 mL/kg/minute (cut point ≤ 7.5 cm/sec, area under the curve = 0.92, P < .0001) and peak VO₂ > 20 mL/kg/minute (cut point > 12.5 cm/sec, area under the curve = 0.84, P < .0001) in comparison with the other cardiac variables of the model (P < .05).

CONCLUSIONS

Peak VO₂ is directly related to measures of LV systolic function, LA compliance, and right ventricle-pulmonary artery coupling, in addition to heart rate and stroke volume and independently of workload, age, and sex. The evaluation of cardiac mechanics may provide more insights into the causes of effort intolerance in subjects from HF stages A-C.

Value of combined cardiopulmonary and echocardiography stress test to characterize the haemodynamic and metabolic responses of patients with heart failure and mid-range ejection fraction

AIMS

To characterize heart failure (HF) with mid-range ejection fraction (HFmrEF), combining cardiopulmonary exercise test, and exercise stress echocardiography.

METHODS AND RESULTS

We studied 169 consecutive subjects (age 62.3 ± 11 years; 74% male): 30 healthy controls, 45 patients with HF and preserved EF (HFpEF), 40 HFmrEF, and 54 with HF and reduced EF (HFrEF). Left ventricular (LV) stroke volume (SV), EF, elastance, global longitudinal strain, E/E', oxygen consumption (VO2), and arterial-venous oxygen content difference (AVO2diff) were measured in all exercise stages. HFmrEF revealed baseline features intermediate between HFrEF and HFpEF, except for B-type natriuretic peptide levels, which was similar to HFpEF and significantly lower than HFrEF. Peak VO2 was not significantly different between HF groups. HFrEF exhibited a significantly lower peak SV as compared to either HFpEF or HFmrEF (74.3 ± 21.8 mL vs. 88.0 ± 17.4 mL and 96.5 ± 25.1 mL; P < 0.01), whereas peak heart rate was not significantly different between HF groups. A significantly reduced AVO2diff at peak exercise was apparent in HFpEF and HFmrEF (15.2 ± 3.3 mL/dL and 13.3 ± 4.2 mL/dL) vs. HFrEF (17.±6.6 mL/dL; P < 0.01), whereas no significant difference was reported between HFpEF and HFmrEF. Multivariate analysis in the overall population and all groups revealed peak parameters as independent predictors of peak VO2 (R2 = 0.90, P < 0.0001); AVO2diff showed the largest standardized regression coefficient.

CONCLUSION

In HFpEF and HFmrEF, effort intolerance is predominantly due to peripheral factors (AVO2diff), whereas in HFrEF peak VO2 is restricted by low increases in SV. Individual therapy according to which component of VO2 is more impaired is advisable.

Cardiopulmonary exercise testing - refining the clinical perspective by combining assessments

INTRODUCTION

Cardiorespiratory fitness (CRF) is now established as a vital sign. Cardiopulmonary exercise testing (CPX) is the gold-standard approach to assessing CRF.

AREAS COVERED

A body of literature spanning several decades clearly supports the clinical utility of CPX in those who are apparently health and at risk for chronic disease as well as numerous patient populations. While CPX, in and of itself, is a valid and reliable clinical assessment, combining findings with other available assessments may provide a more comprehensive perspective that enhances clinical decision making and outcomes. The current review will accomplish the following: (1) define key CPX measures based upon current evidence; and (2) describe the current evidence addressing the relationships between CPX and echocardiography, serum biomarkers, and cardiovascular magnetic resonance.

EXPERT OPINION

Cardiopulmonary exercise testing provides prognostic and diagnostic information in apparently healthy individuals, those at risk for one or more chronic conditions, as well as numerous patient populations. Moreover, if the goal of an intervention is to improve one or more systems integral to the physiologic response to exercise, CPX should be considered as a central assessment to gauge therapeutic efficacy. To further refine the information obtained from CPX, combining other assessments has demonstrated promise.

The year 2018 in the European Heart Journal-Cardiovascular Imaging: Part II

European Heart Journal - Cardiovascular Imaging was launched in 2012 as a multimodality cardiovascular imaging journal. It has gained an impressive impact factor during its first 5 years and is now established as one of the top cardiovascular journals and has become the most important cardiovascular imaging journal in Europe. The most important studies from 2018 will be highlighted in two reports. Part I of the review has focused on studies about myocardial function and risk prediction, myocardial ischaemia, and emerging techniques in cardiovascular imaging, while Part II will focus on cardiomyopathies, congenital heart diseases, valvular heart diseases, and heart failure.

The role of exercise hemodynamics in assessing patients with chronic heart failure and left ventricular assist devices

Introduction: Chronic heart failure is characterized by reduced exercise capacity. Invasive exercise hemodynamics are not routinely performed unless patients undergo transplant or left ventricular assist devices (LVAD) assessment, though now with readily available noninvasive devices, exercise hemodynamics are easily obtained. Our contention is that this is a valuable opportunity to acquire a more accurate measure of cardiac status in heart failure. Exercise hemodynamic measures such as cardiac power output can be carried out cheaply and effectively. Recent studies have highlighted the added value of exercise hemodynamics in prognostication of heart failure, and their role in assessing myocardial recovery in LVADs. Areas covered: In this review, we explore the literature available on Medline until 2019 focusing on resting and exercise hemodynamics alongside the methods of assessment (invasive and noninvasive) in heart failure with reduced ejection fraction and patients with implanted LVADs. Expert opinion: Hemodynamics measured both at rest and exercise are expected to play a significant role in the work up of transplant and LVAD patients. Furthermore, there is the potential to utilize noninvasive assessment in a complimentary fashion to support patient selection and improve the monitoring of response to treatment across the full cohort of heart failure patients.

Cardiac Resynchronization Therapy Optimization: A Comprehensive Approach

Since the first report on biventricular pacing in 1994, cardiac resynchronization therapy (CRT) has become standard for patients with advanced heart failure (HF) and ventricular conduction delay. CRT improves myocardial function by resynchronizing myocardial contraction, which results in reverse left ventricular remodeling and improves symptoms and clinical outcomes. Despite the accelerated development of CRT device technology and its increased application in treating HF patients, almost one-third of these patients do not respond to the therapy or gain any clinical benefit from device implantation. Over the last decade, multiple cardiac imaging modalities have provided a deeper understanding of myocardial pathophysiology, thereby improving HF treatment management. However, the optimal strategy for improving the CRT response remains debatable. This article provides an updated overview of the electropathophysiology of myocardial dysfunction in ventricular conduction delay and the diagnostic approaches involving the use of multiple modalities.