Borguezan-Daros, C

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 Heart failure (HF) with abnormal left ventricular (LV) ejection fraction (EF) manifests in multiple phenotypes, each presenting distinct and potentially actionable therapeutic targets. This study aimed to assess the potential of the ABCDE+ stress echocardiography (SE) protocol in uncovering different phenotypes of non-ischemic HF. Methods With a retrospective analysis of prospectively acquired data, we identified 265 patients (mean age: 65.7±12.6 years; 154 males, 59.9%) with non-ischemic HF with EF<50% (mean =41.4±7.5) enrolled by 23 certified laboratories between 2021 and 2023. Ischemic origin was excluded based on data of angiography and medical history. ABCDE-SE was evaluated with exercise (n=98, 37.0%), dobutamine (n=50, 18.9%), or vasodilators (n=117, 44.1%). The protocol consisted of several steps: A assessed regional wall motion abnormality (RWMA); B evaluated number of B-lines; C measured left ventricular contractile reserve; Step D with coronary flow velocity reserve (CFVR) in the left anterior descending artery (LAD) was completed in 102 patients (38.5%); step E assessed heart rate reserve. Additionally, step F (evaluated in 188 patients at rest and 107 at peak stress) noted the presence of rest or stress-induced moderate-to-severe secondary mitral regurgitation. The SE response was graded on a scale from 0 (all steps normal) to 5 (all ABCDE+ steps abnormal). Results The mean ABCDE score was 1.5±1.2, ranging from 0 (n=59, 22.3%) to 5 (n=2, 0.8%) (see distribution of scores in Figure 1A). Abnormal results were observed in 21 subjects (7.9%) for A, 86 (32.5 %) for B, 147 (55.5%) for C, 42/102 (41.2%) for D, and 101 (38.1%) for E steps. Step F was abnormal in 22/188 (11.8%) at rest and in 16/107 (14.9%) at peak stress. The predominant "solitary phenotypes" (only one step abnormal) were impaired LV contractile function phenotype (step C in 47, 51.1%) followed by chronotropic insufficiency (step E in 17, 18.5%) and congestive phenotype (step B in 17, 18.5%) (see Figure 1B). The most frequent combined phenotype was BCE – congestive phenotype with impaired ventricular and heart rate reserves (28 [62.2%]). Notably, 38 patients (14.3%) demonstrated improved regional contractility, while 27 patients (10.2%) showed new regional wall motion abnormality (see Table). Conclusion Non-ischemic HF patients with abnormal EF exhibit a broad spectrum of phenotypes. Impaired left ventricular contractility, interstitial congestion, and chronotropic insufficiency are the most frequent abnormalities detected by ABCDE-SE. Up to one-quarter of such patients demonstrate normal SE results. This comprehensive approach paves the way for personalized, SE-guided therapy.