Duke Clinical Research Institute, Durham, NC, USA.
Department of Medicine, Duke University School of Medicine, 2400 Pratt Street, NP-8064, Durham, NC, 27705, USA.
Eur J Heart Fail. 2017 Jul;19(7):893-900. doi: 10.1002/ejhf.754. Epub 2017 Feb 14.
While abnormal left ventricular (LV) global longitudinal strain (GLS) has been described in patients with heart failure with preserved ejection fraction (HFpEF), its prevalence and clinical significance are poorly understood.
Patients enrolled in the RELAX trial of sildenafil in HFpEF (LV ejection fraction ≥50%) in whom two-dimensional, speckle-tracking LV GLS was possible (n = 187) were analysed. The distribution of LV GLS and its associations with clinical characteristics, LV structure and function, biomarkers, exercise capacity and quality of life were assessed. Baseline median LV GLS was -14.6% (25th and 75th percentile, -17.0% and -11.9%, respectively) and abnormal (≥ - 16%) in 122/187 (65%) patients. Patients in the tertile with the best LV GLS had lower N-terminal pro-brain natriuretic peptide (NT-proBNP) [median 505 pg/mL (161, 1065) vs. 875 pg/mL (488, 1802), P = 0.008) and lower collagen III N-terminal propeptide (PIIINP) levels [median 6.7 µg/L (5.1, 8.1) vs. 8.1 µg/L (6.5, 10.5), P = 0.001] compared with the tertile with the worst LV GLS. There was also a modest linear relationship with LV GLS and log-transformed NT-proBNP and PIIINP (r = 0.29, P < 0.001 and r = 0.19, P = 0.009, respectively). We observed no linear association of LV GLS with Minnesota Living with Heart Failure scores, 6-min walk distance, peak oxygen consumption, or expiratory minute ventilation/carbon dioxide excretion slope.
Impaired LV GLS is common among HFpEF patients, indicating the presence of covert systolic dysfunction despite normal LV ejection fraction. Impaired LV GLS was associated with biomarkers of wall stress and collagen synthesis and diastolic dysfunction but not with quality of life or exercise capacity, suggesting other processes may be more responsible for these aspects of the HFpEF syndrome.
虽然射血分数保留的心力衰竭（HFpEF）患者存在异常的左心室（LV）整体纵向应变（GLS），但其患病率和临床意义尚不清楚。
对接受 HFpEF 中西地那非 RELAX 试验（LV 射血分数≥50%）且可进行二维斑点追踪 LV GLS 的 187 例患者（n=187）进行了分析。评估了 LV GLS 的分布及其与临床特征、LV 结构和功能、生物标志物、运动能力和生活质量的相关性。基线时，LV GLS 的中位数为-14.6%（25%和 75%分别为-17.0%和-11.9%），122/187（65%）例患者的 LV GLS 异常（≥-16%）。LV GLS 最佳三分位组的患者具有更低的 N 末端脑利钠肽前体（NT-proBNP）[中位数 505pg/mL（161，1065）vs. 875pg/mL（488，1802），P=0.008]和更低的 III 型胶原 N 末端前肽（PIIINP）水平[中位数 6.7μg/L（5.1，8.1）vs. 8.1μg/L（6.5，10.5），P=0.001]。与 LV GLS 最差三分位组相比，LV GLS 与 NT-proBNP 和 PIIINP 的对数呈适度线性关系（r=0.29，P<0.001 和 r=0.19，P=0.009）。我们没有观察到 LV GLS 与明尼苏达心力衰竭生活质量评分、6 分钟步行距离、峰值摄氧量或呼气分钟通气量/二氧化碳排出斜率之间的线性关系。
LV GLS 受损在 HFpEF 患者中很常见，这表明尽管 LV 射血分数正常，但仍存在隐匿性收缩功能障碍。LV GLS 受损与壁应力和胶原合成以及舒张功能障碍的生物标志物相关，但与生活质量或运动能力无关，这表明其他过程可能更负责 HFpEF 综合征的这些方面。
