Faculdade de Ciências Médicas Universidade Estadual de Campinas São Paulo Brazil.
Cardiovascular Imaging Research Center, Division of Cardiology and Department of Radiology, Massachusetts General Hospital Harvard Medical School Boston MA USA.
J Am Heart Assoc. 2024 Jul 16;13(14):e035264. doi: 10.1161/JAHA.124.035264. Epub 2024 Jul 3.
Iodine-meta-iodobenzylguanidine scintigraphy is useful for assessing cardiac autonomic dysfunction and predict outcomes in heart failure (HF). The relationship of cardiac sympathetic function with myocardial remodeling and diffuse fibrosis remains largely unknown. We aimed to evaluate the cardiac sympathetic function of patients with HF and its relation with myocardial remodeling and exercise capacity.
Prospectively enrolled patients with HF (New York Heart Association class II-III) were stratified into HF with preserved left ventricular ejection fraction [LVEF] ≥45%) and reduced LVEF. Ventricular morphology/function and myocardial extracellular volume (ECV) fraction were quantified by cardiovascular magnetic resonance, global longitudinal strain by echocardiography, cardiac sympathetic function by heart-to-mediastinum ratio from iodine-meta-iodobenzylguanidine scintigraphy. All participants underwent cardiopulmonary exercise testing. The cohort included 33 patients with HF with preserved LVEF (LVEF, 60±10%; NT-proBNP [N-terminal pro-B-type natriuretic peptide], 248 [interquartile range, 79-574] pg/dL), 28 with HF with reduced LVEF (LVEF, 30±9%; NT-proBNP, 743 [interquartile range, 250-2054] pg/dL) and 20 controls (LVEF, 65±5%; NT-proBNP, 40 [interquartile range, 19-50] pg/dL). Delayed (4 hours) iodine-meta-iodobenzylguanidine heart-to-mediastinum ratio was lower in HF with preserved LVEF (1.59±0.25) and HF with reduced LVEF (1.45±0.16) versus controls (1.92±0.24; <0.001), and correlated negatively with diffuse fibrosis assessed by ECV (=-0.34, <0.01). ECV in segments without LGE was increased in HF with preserved ejection fraction (0.32±0.05%) and HF with reduced left ventricular ejection fraction (0.31±0.04%) versus controls (0.28±0.04, <0.05) and was associated with the age- and sex-adjusted maximum oxygen consumption (peak oxygen consumption); (=-0.41, <0.01). Preliminary analysis indicates that cardiac sympathetic function might potentially act as a mediator in the association between ECV and NT-proBNP levels.
Abnormally low cardiac sympathetic function in patients with HF with reduced and preserved LVEF is associated with extracellular volume expansion and decreased cardiopulmonary functional capacity.
碘代-间位碘苄胍闪烁显像术可用于评估心脏自主神经功能，并预测心力衰竭（HF）的结局。心脏交感神经功能与心肌重构和弥漫性纤维化之间的关系仍知之甚少。我们旨在评估 HF 患者的心脏交感神经功能及其与心肌重构和运动能力的关系。
前瞻性纳入 HF 患者（纽约心脏协会心功能分级 II-III 级），分为射血分数保留的 HF [左心室射血分数（LVEF）≥45%]和射血分数降低的 HF。心血管磁共振定量心室形态/功能和心肌细胞外容积（ECV）分数，超声心动图定量整体纵向应变，碘代-间位碘苄胍闪烁显像术定量心脏与纵隔比值评估心脏交感神经功能。所有患者均行心肺运动试验。该队列包括 33 例射血分数保留的 HF 患者（LVEF，60±10%；N 端脑利钠肽前体 [NT-proBNP]，248[四分位距，79-574]pg/dL），28 例射血分数降低的 HF 患者（LVEF，30±9%；NT-proBNP，743[四分位距，250-2054]pg/dL）和 20 例对照者（LVEF，65±5%；NT-proBNP，40[四分位距，19-50]pg/dL）。与对照组相比，射血分数保留的 HF 组（1.59±0.25）和射血分数降低的 HF 组（1.45±0.16）延迟（4 小时）碘代-间位碘苄胍心脏与纵隔比值均较低（<0.001），且与 ECV 评估的弥漫性纤维化呈负相关（=-0.34，<0.01）。射血分数保留的 HF 组（0.32±0.05%）和射血分数降低的 HF 组（0.31±0.04%）无晚期钆增强磁共振（LGE）的节段性 ECV 较对照组增加（0.28±0.04，<0.05），与年龄和性别校正的最大摄氧量（峰值摄氧量）呈正相关（=-0.41，<0.01）。初步分析表明，心脏交感神经功能可能是 ECV 与 NT-proBNP 水平之间关联的中介因素。
射血分数降低和保留的 HF 患者的心脏交感神经功能异常降低与细胞外容积扩张和心肺功能能力降低有关。
