Tondi Lara, Pica Silvia, Crimi Gabriele, Disabato Giandomenico, Figliozzi Stefano, Camporeale Antonia, Bernardini Andrea, Tassetti Luigi, Milani Valentina, Piepoli Massimo Francesco, Lombardi Massimo
Multimodality Cardiac Imaging Section, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy.
Multimodality Cardiac Imaging Section, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy.
Int J Cardiol. 2024 Aug 1;408:132135. doi: 10.1016/j.ijcard.2024.132135. Epub 2024 May 4.
Cardiovascular magnetic resonance (CMR) extracellular volume (ECV) allows non-invasive detection of myocardial interstitial fibrosis, which may be related to diastolic dysfunction and left atrial (LA) remodeling in hypertrophic cardiomyopathy (HCM). While the prognostic role of LGE is well-established, interstitial fibrosis and LA dysfunction are emerging novel markers in HCM. This study aimed to explore the interaction between interstitial fibrosis by ECV, LA morpho-functional parameters and adverse clinical outcomes in selected low-risk patients with HCM.
115 HCM patients and 61 matched controls underwent CMR to identify: i) interstitial fibrosis by ECV in hypertrophied left ventricular LGE-negative remote myocardium (r-ECV); ii) LA indexed maximum (LAVi max) and minimum (LAVi min) volumes, ejection fraction (LA-EF) and strain (reservoir εs, conduit εe and booster εa), by CMR feature-tracking. 2D-echocardiographic assessment of diastolic function was also performed within 6 months from CMR. A composite endpoint including worsening NYHA class, heart failure hospitalization, atrial fibrillation and all-cause death was evaluated at 2.3 years follow-up. HCM patients were divided into two groups, according to r-ECV values of controls.
Patients with r-ECV ≥29% (n = 45) showed larger LA volumes (LAVimax 63 vs. 54 ml/m, p < 0.001; LAVimin 43 vs. 28 ml/m, p 〈0001), worse LA function (εs 16 vs. 28%, εe 8 vs. 15%, εa 8 vs. 14%, LA-EF 33 vs. 49%, all p < 0.001) and elevated Nt-proBNP (1115 vs. 382 pg/ml, p = 0.002). LA functional parameters inversely correlated with r-ECV (εs r = -0.54; LA-EF r = -0.46; all p < 0.001) and E/e' (εs r = -0.52, LA-EF r = -0.46; all p < 0.006). r-ECV ≥29% and LAVi min >30 ml/m have been identified as possible independent factors associated with the endpoint.
In HCM diffuse interstitial fibrosis detected by increased r-ECV is associated with LA remodeling and emerged as a potential independent predictor of adverse clinical outcomes, on top of the well-known prognostic impact of LGE.
心血管磁共振成像（CMR）细胞外容积（ECV）能够无创检测心肌间质纤维化，这可能与肥厚型心肌病（HCM）的舒张功能障碍及左心房（LA）重塑有关。虽然延迟强化（LGE）的预后作用已得到充分证实，但间质纤维化和LA功能障碍是HCM中新兴的标志物。本研究旨在探讨选定的低风险HCM患者中，通过ECV检测的间质纤维化、LA形态功能参数与不良临床结局之间的相互作用。
115例HCM患者和61例匹配的对照者接受CMR检查，以确定：i）肥厚的左心室LGE阴性的远隔心肌（r-ECV）中的间质纤维化；ii）通过CMR特征追踪确定LA的最大（LAVi max）和最小（LAVi min）指数容积、射血分数（LA-EF）及应变（储备应变εs、管道应变εe和增强应变εa）。在CMR检查后6个月内还进行了二维超声心动图舒张功能评估。在2.3年的随访中评估包括纽约心脏协会（NYHA）心功能分级恶化、心力衰竭住院、心房颤动和全因死亡的复合终点。根据对照组的r-ECV值将HCM患者分为两组。
r-ECV≥29%的患者（n = 45）显示LA容积更大（LAVimax为63 vs. 54 ml/m，p < 0.001；LAVimin为43 vs. 28 ml/m，p < 0.001），LA功能更差（εs为16 vs. 28%，εe为8 vs. 15%，εa为8 vs. 14%，LA-EF为33 vs. 49%，均p < 0.001）且Nt-proBNP升高（1115 vs. 382 pg/ml，p = 0.002）。LA功能参数与r-ECV呈负相关（εs r = -0.54；LA-EF r = -0.46；均p < 0.001）以及与E/e'呈负相关（εs r = -0.52，LA-EF r = -0.46；均p < 0.006）。r-ECV≥29%和LAVi min > 30 ml/m已被确定为与终点相关的可能独立因素。
在HCM中，通过增加的r-ECV检测到的弥漫性间质纤维化与LA重塑相关，并成为不良临床结局的潜在独立预测因素，这是在LGE已知的预后影响之外。
