Djordjevic‐Dikic, Ana

Abstract Background The functional significance of the left ventricular (LV) hypercontractile phenotype (HP) in hypertrophic cardiomyopathy (HCM) remains unclear. Purpose To assess the systemic and coronary hemodynamic correlates of HP in HCM. Methods 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), end-diastolic volume (EDV), end-systolic volume (ESV), EF, and LV force (systolic blood pressure + LVOTG/ESV, mmHg/mL). Coronary flow velocity in the mid-distal left anterior descending (LAD) coronary artery was assessed in 325 patients. HP was defined as the highest quartile of the force (> 7.32 mmHg/ml). Results Force was moderately related to EF (r = 0.48, p < 0.0001) and weakly to LVOTG (r = 0.36, p < 0.0001). Compared to non-HP patients, HP showed higher heart rate (72 ± 14 vs 67 ± 14 beats per minute, p <0.0001), lower stroke volume (50 ± 22 vs 67 ± 22 ml, p < 0.0001), larger left atrial volume index (44 ± 16 vs 40 ± 16 ml/m2, p = 0.011) and higher coronary flow velocity in the LAD (n = 325, 41 ± 12 vs 37 ± 14 cm/s, p = 0.021), see Figure. Abnormal B-lines (≥ 2) were present in 11 of the 39 HP compared to 39 of the 271 non-HP patients (28% vs 14 %, p = 0.05). E/e’ ratio was higher in HP (n = 59) vs. non-HP (n = 571) patients (11 ± 5.4 vs 9.6 ± 4.2, p = 0.018). Conclusion In patients with HCM, preserved EF, and no history of coronary artery disease, HP identified by resting TTE with supernormal LV force was associated with an unfavorable systemic hemodynamic and coronary flow profile. Compared to non-HP HCM patients, the HP was characterized by reduced stroke volume, impaired diastolic function, and increased resting coronary flow velocity. HP may reflect inefficient myocardial mechanics, with disproportionate energy expenditure mirrored by higher resting coronary flow despite reduced stroke volume generation, ultimately contributing to adverse remodeling and worse prognosisNon-HP vs HP LAVI and coronary LAD flow

Abstract Background Inducible ST-segment depression during stress echocardiography (SE) is associated with a higher risk in patients with inducible regional wall motion abnormality (RWMA). Objective To assess ST segment elevation's prevalence and functional correlates during SE. Methods ECG response was analyzed in 1712 patients (age 63±12 years; 1011 men, 59%) undergoing SE for chronic coronary syndromes (CCS) prospectively recruited at 39 laboratories. Among the patients analyzed, 1286 (75%) performed SE with exercise, 306 (18%) with dobutamine and 120 (7%) with a vasodilator. ECG response was considered abnormal in case of ST-segment shift >1.0 mm from baseline at 80 ms from the J point developed in ≥2 contiguous leads during SE. The stress to rest (∆) change in the wall motion score index (WMSI) was assessed in all patients. Coronary angiography was available in 765 patients. Major adverse cardiac events (MACE) were the outcome measure in 746 patients with follow-up information. Results No significant ST segment shift was observed in 1000 patients (58%, Group 1), ST-segment depression occurred in 609 patients (35.5%, Group 2), and ST-segment elevation in 103 patients (6%, Group 3). ST-segment elevation occurred in 66/1286 patients (5.2%) with exercise, 30/306 with dobutamine (10%), and 7/120 with vasodilators (6%, p = ns vs. exercise and p<0.01 vs. dobutamine). The prevalence of stress-induced RMWA was higher in Group 2 (38.1%) compared to Group 3 (33%) and Group 1 (11.9%. P< 0.001 vs. Groups 2 and 3); however, the ΔWMSI was more pronounced in Group 3 compared to Group 2 and Group 1 (p = ns vs. Group 2 and p<0.001 vs. Group 1). (Figure, left panel). Non-significant CAD (defined as coronary stenosis <50% on coronary angiography) was more prevalent in Group 1 (36%) and 3 (40%) compared to Group 2 (17.5%, p<0.01 vs. Group 1 and 3). . During a median follow-up of 387 days (IQ range 314-603 days), 150 events occurred in 112 patients: 14 all-cause deaths, 39 acute myocardial infarctions, 19 atrial fibrillations, 34 late coronary revascularizations, and 44 acute heart failure hospitalizations. The exposure-adjusted event rate was the lowest in Group 1 compared to Groups 2 and 3 (Figure, right panel). Conclusion In all-comers with CCS, the electrocardiographic pattern of ST-segment elevation is not rare, more frequent with dobutamine, associated with more stress-to-rest change in RWMA and more events despite less extensive underlying anatomic CAD. The paradox of more ischemia with less coronary stenosis is consistent with a coronary vasospastic origin as an important yet frequently overlooked cause of stress-induced ST segment elevation.Figure

Abstract Background Angina with non-obstructive coronary artery disease (ANOCA) is increasingly recognized in clinical practice but effective therapy is difficult to apply due to the heterogeneity of pathophysiological substrates: structural coronary microvascular dysfunction (CMD), functional (vasospastic) CMD, epicardial artery vasospasm, non-cardiac chest pain. Current guidelines recommend invasive coronary function testing with inherent limitations in cost, risk, and access. Objective To evaluate the feasibility of a step-wise, multi-marker, multi-stress assessment of ANOCA patients by stress echocardiography (SE). Methods In an observational, prospective, multicenter, international study, we enrolled 1146 ANOCA patients (age =65.6±11.6years, 636 men, 55, %). All patients underwent a vasodilator SE (adenosine or dipyridamole) with coronary flow velocity reserve (CFVR) measurement in the mid-distal left anterior descending artery (LAD). In a subset of patients with a normal CFVR and strong clinical suspicion for vasospasm, a hyperventilation (HYPER) test (30 deep breaths/min for 5 min) was performed, followed by semi-supine exercise (EX) if negative. Positivity criteria were stress-specific: CFVR < 2.0 for vasodilators; coronary flow velocity (CFV) reduction ≤ 10% from baseline with HYPER; inducible RWMA 2.for HYPER and HYPER-EX Results Of the 1146 patients, 244 (21%) showed abnormal CFVR i.e. structural CMD (Figure 1). In the subset of 68 patients with normal vasodilator CFVR , entering a strategy of sequential stepwise approach, 40 pts underwent HYPER showing a paradoxical vasoconstrictor response despite the increase in the double product (59 %), with RWMA in 11 (16%). Of the remaining patients with normal CFVR and normal response to HYPER, 28 underwent HYPER-EX showing inducible RWMA in 7 (10%) patients. The remaining 21 patients (31%) showed all 3 tests normal: see figure 2. Conclusion In patients with ANOCA, a stepwise multi-marker (CFVR and RWMA) and multi-stress (vasodilators, HYPER, and EX) SE identifies 4 distinct phenotypes and actionable therapeutic targets: structural CMD (reduced CFVR with vasodilator); functional vasospastic CMD (paradoxical decrease of CFV with HYPER), epicardial artery vasospasm (inducible RWMA with HYPER or HYPER-EX); non-cardiac chest pain with normal response all tests and all markers. Our research emphasizes the usefulness of versatile, patient-tailored noninvasive testing in patients with ANOCA to unmask the functional heterogeneity of the endotypes underlying the same phenotype. Figures: 1. Overall population of ANOCA (N=1146)-vasodilator CFVR 2. Pilot study in ANOCA with CFVR>2.0 (N=68)Overall population of ANOCA (N=1146) Pilot study in ANOCA with CFVR>2.0

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

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.

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.

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.

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.

Abstract Background Hypercontractile phenotype of the left ventricle (LV) is an actionable therapeutic target in patients with chronic coronary syndromes (CCS), but its clinical recognition remains elusive. Purpose To assess the clinical variables associated with the hypercontractile phenotype of the LV, identified with supernormal values of an index of LV contractility such as LV force, also known as ventricular elastance. Methods In a prospective, observational, multicenter study, we recruited 5,122 patients (age 65± 11.1 years, 2974 males, 58%) with CCS referred for resting transthoracic echocardiography with technically successful volumetric echocardiography in 17 accredited laboratories. We measured systolic blood pressure (SBP) with a cuff sphygmomanometer. We assessed semi-quantitatively wall motion score index (WMSI), and quantitatively LV end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), force (SBP/ESV), stroke volume (SV), arterial elastance (SBP/SV), ventricular-arterial coupling (VAC, as SV/ESV), and cardiac output (CO = SV*heart rate).Univariable and multivariable logistic regression analysis assessed independent factors associated with the highest force sextile. Odds ratios (ORs) with the corresponding 95% confidence interval (CI) were estimated. Results For all the studied patients, EF was 59±11%. Force was 4.51±2.11 mmHg/ml, with reference sextile = 3.50-4.26 mmHg/ml, lowest sextile (Group 1) <2.60 mmHg/ml and highest sextile (Group 6) > 6.36 mmHg/ml. The correlation between the log of EF and the log of Force was significant with linear regression (r = 0.73, p < 0.001). Patients in the highest sextile of force showed lower values of WMSI, SV, EDV, and ESV, and higher values of arterial elastance and VAC (Table). By multivariable logistic regression model, the highest sextile of force was associated with age > 71 years (OR 4.35, 95% CI 3.06-6.18, p < 0.001), female sex (OR 4.48, 95% CI 3.62-5.54, p < 0.001), absence of beta-blocker therapy (OR 1.56, 95% CI 1.27-1.91), rest SBP> 159 mmHg (OR 6.86, 95% CI 5.03-9.35, p < 0.001), high heart rate (OR 1.03, 95% CI 1.02-1.04, p < 0.001), absence of prior MI (OR 1.31, 95% CI 1-1.72, p = 0.049), and higher LV EF at rest (OR 1.24, 95% CI 1.22-1.26, p < 0.001). Conclusions A hypercontractile phenotype of the LV with high force is associated with a small heart, reduced SV, and higher arterial elastance. It was clinically associated with advanced age, female sex, history of hypertension, absence of beta-blocker therapy, and high resting SBP.

Abstract Background/Introduction Cardiac stress tests are carried out in populations with a low probability of ischemic heart disease (IHD) much more frequently than in the past. Stress ECG remains a frequently used modality for the diagnosis of IHD in vast areas of the world with limited facilities. Purpose To assess the diagnostic value of stress ECG for diagnosing IHD using inducible regional wall motion abnormalities (RWMA) on stress echocardiography (SE) as the gold standard method of diagnosis. Methods The 12-lead ECG response was retrospectively analyzed in 4317 patients (age 64±13 years, 59.6% males) undergoing SE for chronic coronary syndromes who were prospectively recruited from 39 cardiac centers between March 2021 and February 2024. Exclusion criteria were left bundle branch block or pacemaker rhythm. ECG response was considered ischemic according to standard criteria (if ST-segment deviated >1.0 mm from baseline in ≥2 contiguous leads at 80 ms from J point) during an exercise (n=2980, 69.8%), dobutamine (n = 766, 18.0%), or vasodilator (n=519, 12.2%) SE. All patients underwent a comprehensive SE protocol with an assessment of wall motion score index (WMSI), B-lines (4-site simplified score), left ventricular contractile reserve (LVCR) based on force, coronary flow velocity reserve (CFVR) in the mid-distal left anterior descending artery (LAD), and heart rate reserve (HRR). Results ECG changes occurred in 641 patients (14.8%, Group 1) for the overall studied population. Compared to patients without ECG changes (Group 2, n=3676, 85.2%), patients with ECG changes showed higher values of peak WMSI and lower values of CFVR and LVCR (see table).Amongst patients without inducible RWMA (n=3553), there were 392 (11%) patients with an ischemic ECG at stress (89% specificity). Of 764 patients with inducible RWMA during SE, 249 had an ischemic ECG trace (sensitivity 33%). In patients without inducible RWMA, those with ischemic ECG changes showed similar abnormal stress B-lines (23% vs. 21%, p=0.719), LVCR (61% vs. 63%, p=0.602), CFVR (31% vs 33%, p=0.607) and HRR (37% vs 41%, p=0.097) compared to those without ECG changes. Amongst patients with inducible RWMA and ECG changes, CFVR was significantly lower in patients with ECG changes (39.2% and 60.8%, respectively, p<0.001). Conclusions Simple standard stress ECG diagnostic value in the current era in populations with a low probability of IHD seems to be low. However, during SE, stress-induced ischemic ECG changes are associated with more extensive RWMA and blunted global LVCR, with reduced CFVR in the LAD. Therefore, analysis of ST segment changes during stress imaging studies can offer additional, significant information.