Abstract Background Stress echocardiography (SE) was recently upgraded to the ABCDE protocol: step A, regional wall motion abnormalities; step B, B-lines; step C, left ventricular contractile reserve; step D, Doppler-based coronary flow velocity reserve in left anterior descending coronary artery; and step E, EKG-based heart rate reserve. Aim to assess the prognostic value of ABCDE-SE in a prospective, large-scale, multicenter, international, effectiveness study. Methods From July 2016 to November 2024, we enrolled 7896 all-comers (age 65±11 years, 4742 [60.0%] males, ejection fraction 59±10%) with known or suspected chronic coronary syndromes (CCS) referred from 27 certified laboratories. All patients underwent clinically indicated ABCDE-SE, with ACE in all patients, step D in 6286, step B in 5951 and all 5 steps in 5918 pts. The employed stress modality was exercise (n=2407) or pharmacological stress (n=5489; with vasodilator, n=4503; or dobutamine, n=986). Each step was scored from 0 (normal) to 3 (severely abnormal) following EACVI recommendations 2024. SE response ranged from a score of 0 (all steps normal) to a score of 15 (all steps severely abnormal). All-cause death was the only end-point. Results During a median follow-up of 685 days (interquartile range: 387-1227), 370 deaths occurred. Step A negativity was associated with a 1.5% annual mortality. Annual mortality rate ranged from 0.4% persons/year for score 0 (n=958, 12.1%) up to 6.19% person/year for score ≥10 (n=346, 4.3%). (Figure). At multivariate logistic regression analysis, age (hazard ratio [HR] 1.008, 95% interquartile range [IQ]: 1.006-1.010, p<0.001), diabetes (HR 1.564, 95% CI: 1.263-1.936, p<0.001), resting ejection fraction (HR 0.983, 95% CI: 0.974-0.993, p=0.001), and ABCDE score 3-5 (HR 3.111, 95% CI 1.597-6.060, p=0.001), score 6-9 (HR 5.442, 95% CI 2.761-10.729, p<0.001), and score ≥10 (HR 8.826, CI 4.197-18.654, p<0.001) were independent predictors of mortality. Conclusion In patients with known or suspected CCS, SE negativity by simple wall motion criterion is unable to identify a low-risk group. ABCDE-SE allows an effective prediction of survival.Figure
Left ventricular elastance with resting volumetric transthoracic echocardiography identifies different phenotypes in heart failure with preserved ejection fraction
Abstract Background Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous entity including patients with different phenotypes of near normal, normal, and supernormal left ventricular (LV) function. Objectives To assess the value of resting LV elastance (also known as force) with transthoracic echocardiography (TTE) to identify HFpEF phenotypes. Methods In a prospective, observational, multicenter study, 2380 HFpEF patients were recruited from July 2016 to May 2024. Systolic blood pressure (SBP) was measured. We assessed LV end-diastolic volume (EDV), end-systolic volume (ESV), EF, force (SBP/ESV), stroke volume (SV), arterial elastance (AE), ventricular-arterial coupling (VAC), and left atrial volume index (LAVI). Global longitudinal strain (GLS) was available in 1164 (48.9%) patients. 680 patients finished follow-up with a composite end-point of major adverse cardiac events (MACEs). Patients were divided into three groups: low force (< 25th percentile, Group 1, < 3.24 mmHg/ml), intermediate force (≥ 25th percentile and ≤ 75 thpercentile, Group 2, 3.24-5.48 mmHg/ml), and high force (> 75 th percentile, Group 3, >5.48 mmHg/ml). Results The 3 groups showed a gradient with descending values (Group 3>2>1) for SBP, EF, GLS, AE, and VAC, with the opposite gradient (Group 1> 2> 3) for EDV, ESV, SV, and LAVI values (all P<0.01). After a median follow-up of 16 months, 205 MACEs occurred in 138 patients. Cumulative MACEs rate was lowest in group 2 (14.7% person-year), higher in group 1 (16.1% person-year) and 3 (22.9% person-year, log rank p = 0.036). Conclusions HFpEF patients present with different LV contractile phenotypes, easily identified with resting LV force and volumetric TTE. The dominant hemodynamic feature of hypocontractile phenotype is a preload recruitment with larger LV EDV and normal SV, while the hypercontractile phenotype is characterized by a small LV with reduced SV. The hypercontractile and hypocontractile phenotypes are associated with a higher risk of subsequent events.
Functional reserve and prognosis in hypercontractile phenotype patients with heart failure and preserved ejection fraction
Abstract Backgrounds Transthoracic echocardiography (TTE) identifies a peculiar hypercontractile phenotype (HP) in patients with heart failure and preserved ejection fraction (HFpEF) with high resting left ventricular (LV) elastance (also called force). Objectives To assess the functional response and its prognosis associated with HP in HFpEF by stress echocardiography (SE). Methods In a prospective, observational, multicenter study, 1213 patients with HFpEF were divided into two groups based on the highest quartile of rest force: non-hypercontractile phenotype group (non-HP, < 5.64 mmHg/mL, Group 1, n= 910), and HP group (≥5.64 mmHg/mL, Group 2, n= 303). All patients underwent SE with at least 4 of the following stress parameters assessed: wall motion score index (WMSI), B-lines (4-site score), force-based LV contractile reserve, coronary flow velocity reserve (CFVR), and heart rate reserve (HRR). The employed stress was exercise (n=687), dobutamine (n=195), or vasodilators (n=331). SE score ranged from 0 (all steps normal) to 1-5, according to the number of abnormal steps. Follow-up was completed in a subset of 260 patients. Results The 2 groups showed similar values of peak stress WMSI but the global functional burden was higher in Group 2 patients: see table. In a subset of 260 patients who finished follow-up, there were 212 non-HP patients and 48 HP patients. During a median follow-up of 15 months (interquartile range: 10-20), 26 deaths, 20 heart failure (HF) rehospitalizations, and 64 major adverse cardiovascular events (MACEs) occurred. The cumulative HF rehospitalization rate and MACEs rate were higher in HP group (log-rank p<0.01): see figure. Rest force (HR, 1.17; 95% CI: 1.06-1.29; P: 0.040), rest SPAP (HR, 1.08; 95% CI: 1.02-1.14; P: 0.007) and ABCDE score (HR, 1.15; 95% CI: 1.01-1.66; P: 0.032) were independently associated with MACEs. Conclusions HFpEF patients with HP are functionally weaker with multiple vulnerabilities during stress and at higher risk of subsequent events compared to non-HP patients.Relation between resting values of force
Chronotropic incompetence during exercise or pharmacological stress is associated with reduced survival in patients with chronic coronary syndromes
Abstract Aims Chronotropic incompetence (CI) is a biomarker of cardiac autonomic dysfunction. The aim of the study is to assess the risk stratification value of CI during exercise or pharmacological stress echocardiography in patients with chronic coronary syndromes. Methods and results In a prospective, multicenter, international, observational study, we enrolled 13 445 patients with known or suspected chronic coronary syndromes who underwent stress echocardiography in 19 clinical sites from 10 countries using either exercise (n = 2594), dobutamine (n = 2440), or dipyridamole (n = 8411). Heart rate was automatically measured from the 1-lead ECG in the echocardiography monitor. We considered CI as failure to reach 85% of the maximal predicted (220-age) heart rate for exercise and dobutamine, and heart rate reserve (peak/rest heart rate) ≤ 1.22 (≤1.17 if in permanent atrial fibrillation) for dipyridamole stress. The primary outcome was all-cause death. CI was observed in 5045 patients (38%) and stress-induced regional wall motion abnormalities in 1648 (13%). Over a median follow-up time of 3.4 years (interquartile range, 1.6–9.1 years), there were 2426 (18%) deaths. The 10-year mortality was 39% in patients with and 21% in patients without CI (P < 0.0001). CI was associated with a significant increase in 10-year mortality in all age groups ranging from ≤54 years to ≥75 years (P < 0.0001). In addition, it was associated with increased mortality (P < 0.0001) irrespective of β-blocker use. Cox multivariable analysis revealed that CI was an independent predictor of mortality (HR: 1.60, 95% confidence interval: 1.47–1.74; P < 0.0001) together with age, male sex, diabetes mellitus, left ventricular ejection fraction, and resting heart rate. Conclusion In patients with chronic coronary syndromes, CI during exercise or pharmacological stress is a simple and objective predictor of survival.
Hypercontractile phenotype in hypertrophic cardiomyopathy indicates unfavorable hemodynamics, coronary flow and prognosis
Abstract Aims Our aim was to assess the clinical and prognostic significance of the left ventricular (LV) hypercontractile phenotype (HP) in hypertrophic cardiomyopathy (HCM), which until now remains unclear. Methods and results We enrolled 1533 HCM patients (age 51 ± 15 years, 965 males, 63%) with ejection fraction (EF) ≥ 50%, referred for rest transthoracic echocardiography (TTE) in 27 laboratories from 13 countries. Two-dimensional volumetric TTE assessment included LV outflow tract gradient (LVOTG), LV EF, and LV force (systolic blood pressure + LVOTG/ESV, mmHg/mL). HP was defined as the highest quartile of the force (> 7.32 mmHg/mL). Survival analysis was performed in a subset of 1200 patients with follow-up information. Compared with non-HP patients, HP showed higher heart rate (72 ± 14 vs. 67 ± 14 beats per minute, P < 0.001), lower stroke volume (50 ± 22 vs. 67 ± 22 mL, P < 0.001), larger left atrial volume index (44 ± 16 vs. 40 ± 16 mL/m2, P = 0.011) and higher coronary flow velocity in the mid-distal left anterior descending artery (n = 325, 41 ± 12 vs. 37 ± 14 cm/s, P = 0.021). Force was moderately related to LV EF (r = 0.48, P < 0.001) and weakly to LVOTG (r = 0.36, P < 0.001). During a median follow-up of 87 months (interquartile range 45–143 months), 131 all-cause deaths occurred. At multivariable Cox analysis, a force > 7.32 mmHg (the fourth quartile for analyzed patients) was associated with a hazard ratio of 1.44 (95% Confidence intervals 1.00–2.07) for all-cause death, independently of LVOTG and LV EF. Conclusion HP in HCM is associated with a disadvantageous systemic, cardiac and coronary hemodynamic profile as well as lower survival in the long-term.
Stress Echo 2030 Study: A Flagship Project of the Italian Society of Echocardiography and Cardiovascular Imaging
Over the past decade, stress echocardiography has evolved from a test for assessing epicardial artery stenosis to a comprehensive functional test, targeting multiple cardiovascular parameters. The new approach includes several structured steps: (a) evaluating regional wall motion abnormalities to detect epicardial artery stenosis or vasospasm; (b) assessing pulmonary congestion and diastolic function via B-lines with lung ultrasound; (c) gauging preload and contractile reserve with volumetric echocardiography; (d) measuring coronary microvascular reserve using Doppler-based coronary flow velocity in the middistal left anterior descending artery; and (e) determining cardiac sympathetic reserve by tracking heart rate reserve on an ECG. This evolution was supported extensively by the Italian Society of Echocardiography and Cardiovascular Imaging (SIECVI), which played a key role in five areas: (1) developing the initial, curiosity-driven project; (2) disseminating protocols and results at national and international conferences, supporting logistic infrastructure and publication expenses; (3) establishing a digital platform (customized Redcap) for data entry and storage; (4) facilitating patient recruitment across 19 Italian centers; and (5) offering formal endorsement through six presidencies, adding credibility and reach beyond any single institution. The protocol quickly advanced from concept to high-impact publications, earning inclusion in 2024 specialty guidelines. Initially Italian-led, the study now includes 50 centers across 20 countries (e.g. USA and China). Beyond the 50 peer-reviewed papers published in 2016–2024, this study offers a novel, sustainable approach to cardiac stress testing, providing more information at lower costs, with zero radiation and minimal environmental impact. SIECVI’s endorsement was instrumental in amplifying the study’s rigor and outreach.
Unfavorable systemic and coronary hemodynamic profile of left ventricular hypercontractile phenotype in hypertrophic cardiomyopathy
Abstract Background The left ventricular (LV) hypercontractile phenotype (HP) plays a critical role in hypertrophic cardiomyopathy (HCM) and is usually identified with the left ventricular outflow tract gradient (LVOTG). Purpose To assess the systemic and coronary hemodynamic profile associated with HP identified with increased LV elastance (also known as force) at rest in patients with HCM. Methods We enrolled 1248 HCM patients (age 50 ± 15 years, 798 males, 64%) with ejection fraction (EF) ≥50%, referred for rest transthoracic echocardiography (TTE) in 14 quality-controlled sites from 7 countries TTE assessment included LVOTG, EF, and LV force (systolic blood pressure + LVOTG/LV end-systolic volume, mmHg/mL). Volumetric echocardiography with Simpson’s method was used to measure EF from end-diastolic volume (EDV) and end-systolic volume (ESV), stroke volume (SV), arterial elastance (AE) and ventricular-arterial coupling (VAC). We also assessed resting peak diastolic coronary flow velocity (D-CFV) in the mid-distal left anterior descending artery in a subset of 275 patients. Results EF equaled 68 ± 7%, force = 6.8 ± 5.3 mmHg/ml and LVOTG = 22 ± 28 mmHg. HP was identified as the highest quartile of force (> 7.85 mmHg/ml, mean value= 13.3 ± 7.0). HP showed the lowest SV (46 ± 18 ml) and EDV (61 ± 20 ml), with the highest AE (3.19 ± 1.35 mmHg/ml) and VAC (3.46 ± 1.59) compared to other quartiles (p<0.001) ( see Picture) . D-CFV was not higher in patients with HP (n = 65) compared to those (n = 210) without HP (41± 11 vs 38 ± 14 cm/s, p=ns, but higher in comparison to joint first and second Force quartile (n=122) vs 37 ±14 p =0.0472). Table displays the demografic, clinical and TTE parameters related to HP (Table). In multivariate logistic analysis 4 independent predictors of HP were identified: SBP >130 mmHg with OR 2.5, female sex with OR 5.4, LV EF >70% with OR 6.1 and LVOTG >30 mmHg with the highest OR = 6.3. Conclusion: HCM patients with HP exhibit a distinctive systemic hemodynamic and coronary physiology profile, characterized by low SV, high VAC, and supranormal baseline D-CFV compared to non-HP patients. These findings suggest reduced cardiovascular efficiency and increased myocardial oxygen demand, possibly detrimental over time.
Adverse prognostic implications of increased left ventricular force in hypertrophic cardiomyopathy
Abstract Background The left ventricular (LV) force, also known as elastance, serves as a load-independent indicator of contractility and can be noninvasively assessed through echocardiography. In hypertrophic cardiomyopathy (HCM), the heightened presence of the active state of myosin heads results in an increased LV force. Purpose To assess the prognostic value of increased LV elastance at rest in patients with HCM. Methods We enrolled 1420 HCM patients (age 50±16 years, 907 males, 64%) with ejection fraction (EF) ≥50%, referred for rest transthoracic echocardiography (TTE) in 10 quality-controlled labs from 7 countries. TTE assessment included peak left ventricular outflow tract gradient (LVOTG), EF, and LV force (systolic blood pressure + LVOTG/LV end-systolic volume assessed with 2-D, mmHg/mL). All patients were followed up. All-cause death was the outcome measure. Results At a median follow-up of 83 months, 150 deaths occurred (Group 1). At study entry, Group 1 patients had the same ESC-Sudden cardiac death score compared to survivors (Group 2). In Group 1 compared to Group 2, TTE showed higher values of MR severity, E/e’ , left atrial volume index, estimated systolic pulmonary artery pressure, and force (see table). At multivariable Cox analysis, only age (HR =1.08, 95% CI=1.03-1.14, p=0.001) and force > median value of 5.3 mmHg/mL (HR = 2.14, 95% CI 1.53-2.99, p=0.020) were independent predictors of mortality. Ten-year survival was 95% in the pooled first (<3.8 mmHg/mL) and second (3.8-5.2 mmHg/mL) quartiles vs 80% in the pooled third (5.3-7.8 mmHg/mL) and fourth quartiles (>7.8 mmHg/mL), see figure. Conclusion HCM patients with higher values of resting LV elastance show a worse survival, highlighting the dark prognostic side of an excess of force in these patients. Table Legends E/e’, early mitral inflow to early mitral annulus motion ratio, EF, left ventricular ejection fraction, LAVI, left atrial volume index; LVOTG, left ventricular outflow tract peak gradient, MR, mitral regurgitation; MWT, maximal wall thickness, NYHA, New York Heart Association classification, RWT, relative wall thickness; SCD risk, risk score for sudden cardiac death in hypertrophic cardiomyopathy, SPAP, systolic pulmonary arterial pressure.Table.Clinical and TTE findingsFigure.Survival in the force quartiles
Exercise stress echocardiography detects patients with paroxysmal/persistent atrial fibrillation
Abstract Background Atrial fibrillation (AF) is the most prevalent atrial tachyarrhythmia, affecting an estimated 2-4% of adults worldwide. AF is a well-recognized and treatable risk factor for stroke, but it often remains asymptomatic or subclinical, leading to underdiagnosis. This study aimed to identify distinguishing signs during exercise stress echocardiography (ESE) among patients in sinus rhythm (SR), with and without history of paroxysmal/persistent AF (PAF). Methods An international prospective cohort comprising 1035 consecutive patients was initially considered from 12 cardiology institutions. These patients were referred for clinically-driven ESE as part of the Stress Echo 2020-2030 study network. All patients underwent comprehensive ESE with the ABCDE protocol, which included assessment of B-lines, left ventricle contractile reserve (LVCR), ECG-based heart rate reserve (HRR), LV ejection fraction (EF), LV end-diastolic volume, E/e’, pulmonary artery systolic pressure estimation, tricuspid annular plane sytolic excursion (TAPSE), left atrium volume index (LAVi) and left atrium reservoir phase strain (LASr) at rest and with exercise. Results After excluding 89 patients who were in AF during the ESE, 946 patients in SR were included as the main study cohort (101 with and 845 without a history of PAF). A scoring system was then constructed using all independent variables that differentiate the two groups (those with and without history of PAF). Presence of systemic hypertension, rest LAVI>31ml/m2, rest |LASr|< 21%, stress LAVI >29 ml/m2, stress |LASr| <24%, stress E/e’ >7, ∆TAPSE <4.5 mm, HRR<1.87, and LVCR<1.6 were identified as the discriminators between patients with and without PAF. The composite score, summing all 9 items (with a total score range from 0 to 9), yielded a score of >4 as the best balance between sensitivity (87%) and specificity (60%) in predicting those with PAF. The receiver operating characteristic curve analysis of the scoring model showed an AUC of 0.79 (p-value <0.0001), Figure. Conclusion ESE evaluation can be a valuable adjunct for identifying patients in SR with history of PAF. This multifaceted approach enhances the potential for more accurate detection and clinical management of individuals in SR at risk for AF, who could be considered for aggressive monitoring programs to prevent the development of new onset AF and subsequent increase in cardiovascular risk.
Prognostic role of exercise stress echocardiography in asymptomatic severe aortic stenosis
Abstract Background Guidelines recognize the role of exercise stress testing in evaluating functional capacity in patients with asymptomatic severe aortic stenosis (AS). The study aimed to identify the prognostic role of exercise stress echocardiography (ESE) in asymptomatic severe AS. Methods We enrolled 153 asymptomatic patients (70±13 years; 88 male, 57%) with severe AS, aortic valve area (AVA) <1.0 cm2, mean aortic gradient ≥ 40 mmHg, ejection fraction (EF) ≥55%. All were referred for ESE in 7 quality-controlled centers from 5 countries. Rest and ESE assessment also included global longitudinal strain (GLS) and left atrial volume index (LAVI). B-lines were assessed by LUS with the 4-site simplified scan of the third intercostal space. A 4-point ESE score was based on 4 parameters (0 for normal, 1 for abnormal), with the following pre-determined cutoffs of abnormality: ∆-maximal aortic gradient (MAG) ≥20 mmHg; GLS at peak ≤ 19%, according to receiver operating characteristics curve analysis, stress B-lines ≥2; stress LAVI ≥ 34 mL/m2. Follow-up was completed in 142/153 patients (92%). Results At rest, AVA was 0.85±0.14 cm2, maximal aortic gradient: 79±14 mmHg, and peak aortic velocity: 4.42 ± 0.41 m/s. Mean EF at rest: 63.4±5.3% During a median follow-up of 1802 days (IQ range 651-2302), 41 events occurred in 39 patients: 15 all-cause deaths, 17 acute HF, 1 stroke, 1 myocardial infarction, and 7 coronary revascularization. Patients experiencing events displayed a greater increase in MAG during peak ESE, more B-lines with exercise, greater degree of LAVI dilation with exercise and slightly lower GLS compared to those without events (Table). Increase in ESE score was associated with a significant rise (p=0.001) in event incidence from score 0 (n=0/13, 0%) to score 1 (n=2/21, 9.5%), score 2 (n=10/42, 23.8%), and ≥3 (n=27/66, 40.9%), see figure. Conclusions In asymptomatic severe AS cases with preserved LV EF, comprehensive ESE provides early marker of potential cardiac decompensation at follow-up. The composite ESE index, including MAG, GLS, LAVI, and B-lines, holds promise as a prognostic predictor.TableFigure