Multiple Phenotypes of Chronic Coronary Syndromes Identified by ABCDE Stress Echocardiography.

BACKGROUND: Regional wall motion abnormality is considered a sensitive and specific marker of ischemia during stress echocardiography (SE). However, ischemia is a multifaceted entity associated with either coronary artery disease (CAD) or angina with normal coronary arteries, a distinction difficult to make using a single sign. The aim of this study was to evaluate the diagnostic potential of the five-step ABCDE SE protocol for CAD detection. METHODS: From the 2016-2022 Stress Echo 2030 study data bank, 3,229 patients were selected (mean age, 66 ± 12 years; 2,089 men [65%]) with known CAD (n = 1,792) or angina with normal coronary arteries (n = 1,437). All patients were studied using both the ABCDE SE protocol and coronary angiography, within 3 months. In step A, regional wall motion abnormality is assessed; in step B, B-lines and diastolic function; in step C, left ventricular contractile reserve; in step D, coronary flow velocity reserve in the left anterior descending coronary artery; and in step E, heart rate reserve. RESULTS: SE response ranged from a score of 0 (all steps normal) to a score of 5 (all steps abnormal). For CAD, rates of abnormal results were 347 for step A (19.4%), 547 (30.5%) for step B, 720 (40.2%) for step C, 615 (34.3%) for step D, and 633 (35.3%) for step E. For angina with normal coronary arteries, rates of abnormal results were 81 (5.6%) for step A, 429 (29.9%) for step B, 432 (30.1%) for step C, 354 (24.6%) for step D, and 445 (31.0%) for step E. The dominant "solitary phenotype" was step B in 109 patients (9.1%). CONCLUSIONS: Stress-induced ischemia presents with a wide range of diagnostic phenotypes, highlighting its complex nature. Using a comprehensive approach such as the advanced ABCDE score, which combines multiple markers, proves to be more valuable than relying on a single marker in isolation.

Rest and Stress Left Atrial Dysfunction in Patients with Atrial Fibrillation.

BACKGROUND: Left atrial (LA) myopathy with paroxysmal and permanent atrial fibrillation (AF) is frequent in chronic coronary syndromes (CCS) but sometimes occult at rest and elicited by stress. AIM: This study sought to assess LA volume and function at rest and during stress across the spectrum of AF. METHODS: In a prospective, multicenter, observational study design, we enrolled 3042 patients [age = 64 ± 12; 63.8% male] with known or suspected CCS: 2749 were in sinus rhythm (SR, Group 1); 191 in SR with a history of paroxysmal AF (Group 2); and 102 were in permanent AF (Group 3). All patients underwent stress echocardiography (SE). We measured left atrial volume index (LAVI) in all patients and LA Strain reservoir phase (LASr) in a subset of 486 patients. RESULTS: LAVI increased from Group 1 to 3, both at rest (Group 1 = 27.6 ± 12.2, Group 2 = 31.6 ± 12.9, Group 3 = 43.3 ± 19.7 mL/m2, p < 0.001) and at peak stress (Group 1 = 26.2 ± 12.0, Group 2 = 31.2 ± 12.2, Group 3 = 43.9 ± 19.4 mL/m2, p < 0.001). LASr progressively decreased from Group 1 to 3, both at rest (Group 1 = 26.0 ± 8.5%, Group 2 = 23.2 ± 11.2%, Group 3 = 8.5 ± 6.5%, p < 0.001) and at peak stress (Group 1 = 26.9 ± 10.1, Group 2 = 23.8 ± 11.0 Group 3 = 10.7 ± 8.1%, p < 0.001). Stress B-lines (≥2) were more frequent in AF (Group 1 = 29.7% vs. Group 2 = 35.5% vs. Group 3 = 57.4%, p < 0.001). Inducible ischemia was less frequent in SR (Group 1 = 16.1% vs. Group 2 = 24.7% vs. Group 3 = 24.5%, p = 0.001). CONCLUSIONS: In CCS, rest and stress LA dilation and reservoir dysfunction are often present in paroxysmal and, more so, in permanent AF and are associated with more frequent inducible ischemia and pulmonary congestion during stress.

Feasibility and value of two-dimensional volumetric stress echocardiography.

BACKGROUND: Stroke volume response during stress is a major determinant of functional status in heart failure and can be measured by two-dimensional (2-D) volumetric stress echocardiography (SE). The present study hypothesis is that SE may identify mechanisms underlying the change in stroke volume by measuring preload reserve through end-diastolic volume (EDV) and left ventricular contractile reserve (LVCR) with systolic blood pressure and end-systolic volume (ESV). METHODS: We enrolled 4735 patients (age 63.6±11.3 years, 2800 male) referred to SE for known or suspected coronary artery disease (CAD) and/or heart failure (HF) in 21 SE laboratories in 8 countries. In addition to regional wall motion abnormalities (RWMA), force was measured at rest and peak stress as the ratio of systolic blood pressure by cuff sphygmomanometer/ESV by 2D with Simpson's or linear method. Abnormal values of LVCR (peak/rest) based on force were ≤1.10 for dipyridamole (N.=1992 patients) and adenosine (N.=18); ≤2.0 for exercise (N.=2087) or dobutamine (N.=638). RESULTS: Force-based LVCR was obtained in all 4735 patients. Lack of stroke volume increase during stress was due to either abnormal LVCR and/or blunted preload reserve, and 57% of patients with abnormal LVCR nevertheless showed increase in stroke volume. CONCLUSIONS: Volumetric SE is highly feasible with all stresses, and more frequently impaired in presence of ischemic RWMA, absence of viability and reduced coronary flow velocity reserve. It identifies an altered stroke volume response due to reduced preload and/or contractile reserve.

Stress Echo 2030: The Novel ABCDE-(FGLPR) Protocol to Define the Future of Imaging.

With stress echo (SE) 2020 study, a new standard of practice in stress imaging was developed and disseminated: the ABCDE protocol for functional testing within and beyond CAD. ABCDE protocol was the fruit of SE 2020, and is the seed of SE 2030, which is articulated in 12 projects: 1-SE in coronary artery disease (SECAD); 2-SE in diastolic heart failure (SEDIA); 3-SE in hypertrophic cardiomyopathy (SEHCA); 4-SE post-chest radiotherapy and chemotherapy (SERA); 5-Artificial intelligence SE evaluation (AI-SEE); 6-Environmental stress echocardiography and air pollution (ESTER); 7-SE in repaired Tetralogy of Fallot (SETOF); 8-SE in post-COVID-19 (SECOV); 9: Recovery by stress echo of conventionally unfit donor good hearts (RESURGE); 10-SE for mitral ischemic regurgitation (SEMIR); 11-SE in valvular heart disease (SEVA); 12-SE for coronary vasospasm (SESPASM). The study aims to recruit in the next 5 years (2021-2025) ≥10,000 patients followed for ≥5 years (up to 2030) from ≥20 quality-controlled laboratories from ≥10 countries. In this COVID-19 era of sustainable health care delivery, SE2030 will provide the evidence to finally recommend SE as the optimal and versatile imaging modality for functional testing anywhere, any time, and in any patient.

Sustainability and Versatility of the ABCDE Protocol for Stress Echocardiography.

For the past 40 years, the methodology for stress echocardiography (SE) has remained basically unchanged. It is based on two-dimensional, black and white imaging, and is used to detect regional wall motion abnormalities (RWMA) in patients with known or suspected coronary artery disease (CAD). In the last five years much has changed and RWMA is not enough on its own to stratify patient risk and dictate therapy. Patients arriving at SE labs often have comorbidities and are undergoing full anti-ischemic therapy. The SE positivity rate based on RWMA fell from 70% in the eighties to 10% in the last decade. The understanding of CAD pathophysiology has shifted from a regional hydraulic disease to a systemic biologic disease. The conventional view of CAD encouraged the use of coronary anatomic imaging for diagnosis and the oculo-stenotic reflex for the deployment of therapy. This has led to a clinical oversimplification that ignores the lessons of pathophysiology and epidemiology, and in fact, CAD is not synonymous with ischemic heart disease. Patients with CAD may also have other vulnerabilities such as coronary plaque (step A of ABCDE-SE), alveolar-capillary membrane and pulmonary congestion (step B), preload and contractile reserve (step C), coronary microcirculation (step D) and cardiac autonomic balance (step E). The SE methodology based on two-dimensional echocardiography is now integrated with lung ultrasound (step B for B-lines), volumetric echocardiography (step C), color- and pulsed-wave Doppler (step D) and non-imaging electrocardiogram-based heart rate assessment (step E). In addition, qualitative assessment based on the naked eye has now become more quantitative, has been improved by contrast and based on cardiac strain and artificial intelligence. ABCDE-SE is now ready for large scale multicenter testing in the SE2030 study.

Functional, Anatomical, and Prognostic Correlates of Coronary Flow Velocity Reserve During Stress Echocardiography.

BACKGROUND: The assessment of coronary flow velocity reserve (CFVR) in left anterior descending coronary artery (LAD) expands the risk stratification potential of stress echocardiography (SE) based on stress-induced regional wall motion abnormalities (RWMA). OBJECTIVES: The purpose of this study was to assess the feasibility and functional correlates of CFVR. METHODS: This prospective, observational, multicenter study initially screened 3,410 patients (2,061 [60%] male; age 63 ± 11 years; ejection fraction 61 ± 9%) with known or suspected coronary artery disease and/or heart failure. All patients underwent SE (exercise, n = 1,288; vasodilator, n = 1,860; dobutamine, n = 262) based on new or worsening RWMA in 20 accredited laboratories of 8 countries. CFVR was calculated as the stress/rest ratio of diastolic peak flow velocity pulsed-Doppler assessment of LAD flow. A subset of 1,867 patients was followed up. RESULTS: The success rate for CFVR on LAD was 3,002 of 3,410 (feasibility = 88%). Reduced (≤2.0) CFVR was found in 896 of 3,002 (30%) patients. At multivariable logistic regression analysis, inducible RWMA (odds ratio [OR]: 6.5; 95% confidence interval [CI]: 4.9 to 8.5; p < 0.01), abnormal left ventricular contractile reserve (OR: 3.4; 95% CI: 2.7 to 4.2; p < 0.01), and B-lines (OR: 1.5; 95% CI: 1.1 to 1.9; p = 0.01) were associated with reduced CFVR. During a median follow-up time of 16 months, 218 events occurred. RWMA (hazard ratio: 3.8; 95% CI: 2.3 to 6.3; p < 0.001) and reduced CFVR (hazard ratio: 1.5; 95% CI: 1.1 to 2.2; p = 0.009) were independently associated with adverse outcome. CONCLUSIONS: CFVR is feasible with all SE protocols. Reduced CFVR is often accompanied by RWMA, abnormal LVCR, and pulmonary congestion during stress, and shows independent value over RWMA in predicting an adverse outcome.