Serenelli Matteo, Cantone Anna, Dal Passo Beatrice, Sanguettoli Federico, Fabbri Gioele, Guidi Colombi Gabriele, Maio Daniele, Arzenton Matteo, Vitali Martina, Pavasini Rita, Campo Gianluca
Cardiology Unit, Azienda Ospedaliera Universitaria di Ferrara, Cona, Ferrara, Italy.
J Cardiovasc Med (Hagerstown). 2025 Feb 1;26(2):81-87. doi: 10.2459/JCM.0000000000001690. Epub 2024 Dec 26.
Cardiac amyloidosis typically causes restrictive cardiomyopathy, in which the impairment of diastolic function is dominant. Echocardiography provides prognostic information through some important parameters: left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS). However, LVEF often remains preserved despite disease progression, and GLS is not routinely performed as it is limited by suboptimal image quality. The stroke volume index (SVi) has already been shown to correlate with mortality in heart failure patients; still, its prognostic role in transthyretin cardiac amyloidosis (TTR-CA) is poorly studied.
This prospective study aimed to evaluate the role of SVi in predicting mortality and heart failure hospitalizations in patients with cardiac amyloidosis, comparing it to other parameters of left ventricular performance.
Baseline clinical transthoracic echocardiogram and laboratory data were collected prospectively in 115 patients with diagnosed TTR-CA. The outcome was the occurrence of the composite of heart failure hospitalization and death and its association with SVi, LVEF, GLS and MCF was tested by Cox proportional hazard modelling.
Over a mean follow-up of 16.1 months (interquartile range 7.4-24.9 months), 29 patients died, and 19 were hospitalized for heart failure. SVi was associated with the composite outcome of death and heart failure hospitalization [hazard ratio 0.96; 95% confidence interval (CI) 0.93-0.99] and remained an independent predictor of outcome after adjustment for NAC stage, mitral regurgitation degree, age and the use of disease-modifying treatment. The best cut-off of SVi to predict outcome was 35 ml/m2 (hazard ratio 2.30; 95% CI 1.03-5.17).
SVi is superior to LVEF, MCF, and GLS for prognostication in patients with TTR amyloidosis.
心脏淀粉样变性通常会导致限制性心肌病，其中舒张功能障碍占主导。超声心动图通过一些重要参数提供预后信息：左心室射血分数（LVEF）和整体纵向应变（GLS）。然而，尽管疾病进展，LVEF通常仍保持正常；并且由于图像质量欠佳限制了GLS的常规应用。每搏输出量指数（SVi）已被证明与心力衰竭患者的死亡率相关；尽管如此，其在转甲状腺素蛋白心脏淀粉样变性（TTR-CA）中的预后作用仍研究不足。
本前瞻性研究旨在评估SVi在预测心脏淀粉样变性患者死亡率和心力衰竭住院方面的作用，并将其与左心室功能的其他参数进行比较。
前瞻性收集了115例确诊为TTR-CA患者的基线临床经胸超声心动图和实验室数据。观察终点为心力衰竭住院和死亡的复合事件，并通过Cox比例风险模型检验其与SVi、LVEF、GLS和心肌纤维化分数（MCF）的相关性。
平均随访16.1个月（四分位间距7.4 - 24.9个月），29例患者死亡，19例因心力衰竭住院。SVi与死亡和心力衰竭住院的复合结局相关[风险比0.96；95%置信区间（CI）0.93 - 0.99]，并且在调整NAC分期、二尖瓣反流程度、年龄和使用疾病修饰治疗后，仍是结局的独立预测因子。预测结局的SVi最佳截断值为35ml/m²（风险比2.30；95%CI 1.03 - 5.17）。
在TTR淀粉样变性患者的预后评估中，SVi优于LVEF、MCF和GLS。
