Coronary Flow, Left Ventricular Contractile and Heart Rate Reserve in Non-Ischemic Heart Failure.

Background: Left ventricular contractile reserve (LVCR), coronary flow velocity reserve (CFVR), and heart rate reserve (HRR) affect outcome in heart failure (HF). They can be simultaneously measured during dipyridamole stress echocardiography (DSE). Aim: To assess the value of comprehensive DSE in patients with non-ischemic HF. Methods: We evaluated 610 patients with HF, no history of coronary artery disease, and no inducible regional wall motion abnormalities: 270 patients with preserved ejection fraction (≥50%), 146 patients with mid-range ejection fraction (40-49%), and 194 patients with reduced ejection fraction (<40%). All underwent DSE (0.84 mg/kg in 6') in 7 accredited laboratories. We measured LVCR (abnormal value ≤ 1.1), CFVR in left anterior descending artery (abnormal value: ≤2.0), and HRR (peak/rest heart rate; abnormal value: ≤1.22). All patients were followed up. Results: Abnormal CFVR, LVCR, and HRR occurred in 29%, 45%, and 47% of patients, respectively (p < 0.001). After a median follow-up time of 20 months (interquartile range: 12-32 months), 113 hard events occurred in 105 patients with 41 deaths, 8 myocardial infarctions, 61 admissions for acute HF, and 3 strokes. The annual mortality rates were 0.8% in 200 patients with none abnormal criteria, 1.8% in 184 patients with 1 abnormal criterion, 7.1% in 130 patients with 2 abnormal criteria, 7.5% in 96 patients with 3 abnormal criteria. Conclusions: Abnormal LVCR, CFVR, and HRR were frequent during DSE in non-ischemic HF patients. They target different pathophysiological vulnerabilities (myocardial function, coronary microcirculation, and cardiac autonomic balance) and are useful for outcome prediction.

Hemodynamic Heterogeneity of Reduced Cardiac Reserve Unmasked by Volumetric Exercise Echocardiography.

BACKGROUND: Two-dimensional volumetric exercise stress echocardiography (ESE) provides an integrated view of left ventricular (LV) preload reserve through end-diastolic volume (EDV) and LV contractile reserve (LVCR) through end-systolic volume (ESV) changes. PURPOSE: To assess the dependence of cardiac reserve upon LVCR, EDV, and heart rate (HR) during ESE. METHODS: We prospectively performed semi-supine bicycle or treadmill ESE in 1344 patients (age 59.8 ± 11.4 years; ejection fraction = 63 ± 8%) referred for known or suspected coronary artery disease. All patients had negative ESE by wall motion criteria. EDV and ESV were measured by biplane Simpson rule with 2-dimensional echocardiography. Cardiac index reserve was identified by peak-rest value. LVCR was the stress-rest ratio of force (systolic blood pressure by cuff sphygmomanometer/ESV, abnormal values ≤2.0). Preload reserve was defined by an increase in EDV. Cardiac index was calculated as stroke volume index * HR (by EKG). HR reserve (stress/rest ratio) <1.85 identified chronotropic incompetence. RESULTS: Of the 1344 patients, 448 were in the lowest tertile of cardiac index reserve with stress. Of them, 303 (67.6%) achieved HR reserve <1.85; 252 (56.3%) had an abnormal LVCR and 341 (76.1%) a reduction of preload reserve, with 446 patients (99.6%) showing ≥1 abnormality. At binary logistic regression analysis, reduced preload reserve (odds ratio [OR]: 5.610; 95% confidence intervals [CI]: 4.025 to 7.821), chronotropic incompetence (OR: 3.923, 95% CI: 2.915 to 5.279), and abnormal LVCR (OR: 1.579; 95% CI: 1.105 to 2.259) were independently associated with lowest tertile of cardiac index reserve at peak stress. CONCLUSIONS: Heart rate assessment and volumetric echocardiography during ESE identify the heterogeneity of hemodynamic phenotypes of impaired chronotropic, preload or LVCR underlying a reduced cardiac reserve.

Entrenamiento por etapas basado en la web: el camino hacia el Eco Estrés 2020 / Multi-step Web-based Training: the Road to Stress Echo 2020

RESUMEN Introducción: Una plataforma de entrenamiento estandarizada ayuda a armonizar la lectura de la ecocardiografía de estrés (EE) más allá de las anormalidades en la motilidad parietal regional (AMPR) Objetivo: Armonizar los criterios de lectura del EE a través de diferentes laboratorios. Métodos: El laboratorio central preparó para los lectores de ecocardiografía un módulo obligatorio de 5 parámetros basado en la web de 2 horas de duración: AMPR; líneas B, reserva de la velocidad de flujo coronario (RVFC) evaluada mediante la velocidad pico del flujo diastólico en la arteria coronaria descendente anterior; reserva contráctil ventricular izquierda (RCVI, evaluada a partir de mediciones crudas del volumen de fin de sístole, VFS); y presión sistólica de la arteria pulmonar (basada en mediciones crudas de la velocidad del jet de regurgitación tricuspídea, VRT). La prueba de control de calidad consistió en 20 casos seleccionados por el centro coordinador. El umbral de aprobación determinado a priori fue de 18/20 (> 90%) con un coeficiente de correlación intraclase entre el laboratorio coordinador y el lector periférico > 0.90. Resultados: Ochenta y cuatro lectores completaron la certificación para las AMPR, 65 para las líneas B, 30 para la RVFC, 24 para el VFS y 20 para la VRT. El tiempo de lectura medio por intento fue más corto para la VRT (9 ± 4 min), la RVFC (13 ± 6 min) y las líneas B (17 ± 3 min), intermedio para el VFS (24 ± 7 min), y más prolongado para las AMPR (29 ± 12 min, p < 0.01). La tasa de acierto del primer intento fue más alta para la RVFC (85%), intermedia para la VRT (75%) y las líneas B (43%), menor para el VFS (35%) y más baja para las AMPR (28%, p < 0.01). Conclusiones: La plataforma de aprendizaje basada en la web mejora las habilidades de interpretación de imágenes sin necesidad de un equipamiento de imágenes costoso o de estudiar un paciente. El camino hacia la certificación es más largo para las AMPR, intermedio para el VFS y más corto para la VRT, la RVFC y las líneas B.

ABSTRACT Background: A standardized training platform helps to achieve reading harmonization in stress echocardiography (SE) beyond regional wall motion abnormalities (RWMA). Objective: To harmonize SE reading criteria across different laboratories. Methods: The core lab prepared for readers an obligatory 2-hour web-based learning module for 5 parameters: RWMA; B-lines; coronary flow velocity reserve (CFVR) based on peak diastolic flow velocity on the left anterior descending coronary artery; left ventricular contractile reserve (LVCR, from raw measurementis of end-systolic volume, ESV); systolic arterial pulmonary pressure (from raw measurementis of peak tricuspid regurgitant jet velocity, TRV). The quality control test consisted of 20 cases selected by the coordinating center. The a priori determined pass threshold was 18/20 (>90%) with intra-class correla-tion coefficient between the coordinating lab and the peripheral reader >0.90. Resultis: The certification was completed by 84 readers for RWMA, 65 for B-lines, 30 for CFVR, 24 for ESV and 20 for TRV The mean reading time per attempt was shorter for TRV (9±4 min), CFVR (13±6 min) and B-lines (17±3 min), intermedi-ate for ESV (24±7 min), and longer for RWMA (29±12 min, p <0.01). The success rate of the first attempt was higher for CFVR (85%), intermediate for TRV (75%) and B-lines (43 %), lower for ESV (35%) and lowest for RWMA (28 %, p <0.01). Conclusions: A web-based learning platform improves image interpretation skills without need for expensive imaging equip-ment or a patient to scan. The road to certification is longer for RWMA, intermediate for ESV, and shorter for TRV, CFVR and B-lines.