Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Headley Way, Oxford, OX3 9DU, UK.
Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.
J Cardiovasc Magn Reson. 2022 Jun 13;24(1):36. doi: 10.1186/s12968-022-00868-y.
The right ventricle (RV) in hypertrophic cardiomyopathy (HCM) tends to be neglected, as previous efforts have predominantly focused on examining the prognostic value of left ventricular (LV) abnormalities. The objectives of this study were to assess RV function in HCM, changes over time, and association with clinical outcomes.
Two hundred and ninety HCM patients with preserved LV ejection fraction (LVEF ≥ 55%) and 30 age- and sex-matched controls underwent cardiovascular magnetic resonance (CMR). All patients were followed up for clinical events for a median duration of 4.4 years. Sixty-three patients had a follow-up CMR undertaken at a median interval of 5.4 years. Main study measures and outcomes were RV function (RV ejection fraction (RVEF) and RV strain) at baseline, temporal changes in RV function over time and prognostic value of RV dysfunction for predicting cardiovascular outcomes in HCM.
When compared to controls, HCM patients exhibited lower RV and LV peak global longitudinal systolic strains on feature-tracking analysis of cine images, while RVEF and LVEF were within the normal range. On follow-up CMR, both RV and LV strain parameters decreased over time. RVEF decreased at follow-up (65 ± 7% to 62 ± 7%, P < 0.001) but the change in LVEF was not significant (68 ± 10% to 66 ± 8%, P = 0.30). On clinical follow up, reduced RVEF was an independent predictor of non-sustained ventricular tachycardia (NSVT) [HR 1.10 (95% CI 1.06-1.15), P < 0.001] and composite cardiovascular events (NSVT, stroke, heart failure hospitalisation and cardiovascular death) [HR 1.07 (95% CI 1.03-1.10), P < 0.001]. RV longitudinal strain was an independent predictor of NSVT [HR 1.05 (95% CI 1.01-1.09), P = 0.029]. Patients with RVEF < 55% showed an increased risk of NSVT and composite cardiovascular events. In contrast, LVEF and LV global longitudinal strain were not predictive of such events on multivariable analysis.
In HCM, RV function, including RV strain, and LV strain decrease over time despite preserved LVEF. Reduction in RV but not LV function is associated with adverse cardiovascular outcomes. Assessing RV function in early HCM disease might have a role in risk stratification to prevent future cardiovascular events.
肥厚型心肌病（HCM）患者的右心室（RV）往往被忽视，因为之前的研究主要集中在检查左心室（LV）异常的预后价值上。本研究的目的是评估 HCM 患者的 RV 功能、随时间的变化以及与临床结局的关系。
290 名左心室射血分数（LVEF≥55%）保留的 HCM 患者和 30 名年龄和性别匹配的对照组接受心血管磁共振（CMR）检查。所有患者的中位随访时间为 4.4 年，以记录临床事件。63 名患者在中位随访间隔 5.4 年时接受了随访 CMR。主要研究指标和结局为基线时的 RV 功能（RV 射血分数（RVEF）和 RV 应变）、随时间 RV 功能的变化以及 RV 功能障碍对预测 HCM 患者心血管结局的预后价值。
与对照组相比，HCM 患者的电影图像特征追踪分析显示 RV 和 LV 峰值整体纵向收缩应变较低，而 RVEF 和 LVEF 均在正常范围内。在随访 CMR 中，RV 和 LV 应变参数随时间逐渐降低。随访时 RVEF 降低（65±7%至 62±7%，P<0.001），但 LVEF 变化不显著（68±10%至 66±8%，P=0.30）。在临床随访中，降低的 RVEF 是非持续性室性心动过速（NSVT）[风险比（HR）1.10（95%置信区间（CI）1.06-1.15），P<0.001]和复合心血管事件（NSVT、卒、心力衰竭住院和心血管死亡）[HR 1.07（95% CI 1.03-1.10），P<0.001]的独立预测因素。RV 纵向应变是 NSVT 的独立预测因素[HR 1.05（95% CI 1.01-1.09），P=0.029]。RVEF<55%的患者发生 NSVT 和复合心血管事件的风险增加。相比之下，LVEF 和 LV 整体纵向应变在多变量分析中均不能预测此类事件。
在 HCM 中，尽管 LVEF 保留，但 RV 功能（包括 RV 应变和 LV 应变）随时间逐渐下降。RV 功能下降而不是 LV 功能下降与不良心血管结局相关。在早期 HCM 疾病中评估 RV 功能可能在危险分层中发挥作用，以预防未来的心血管事件。
