从医学影像到临床诊疗:2023年心血管磁共振进展

心血管磁共振(cardiovascular magnetic resonance, CMR)具有无创、无辐射、多参数成像的优势,能够实现对心脏形态、功能和组织学信息的“一站式”评估,在心血管疾病的精准医疗中发挥着无可替代的重要作用。2023年CMR研究取得了长足的进展:组织特征成像、心肌应变分析等技术不断推陈出新,探索更多临床适应证,并逐步完成标准化应用转化;非缺血性心脏病、缺血性心脏病等领域的CMR应用在新版指南中备受重视,且优质循证证据不断涌现,鼓励其更多地参与到心血管临床管理之中。本文将从技术和临床应用两方面系统性回顾其中代表性成果,以期为现阶段医疗实践提供实时有效的指导。

心脏MRI新技术及其应用进展

近年来心脏磁共振(CMR)成像在心血管系统疾病的无创性评估中发挥了重要作用。其主要成像方法包括心肌组织学特征成像、MR指纹成像(MRF)、特征追踪(FT)技术、定量灌注成像、扩散加权成像(DWI)、扩散张量成像(DTI)和四维血流成像等。CMR现已越来越广泛地用于缺血性心脏病、非缺血性心脏病、大血管疾病等多种心血管疾病的临床诊断和预后评估。就CMR最新技术及应用进展进行评述。

Tumour seeding after percutaneous cryoablation for hepatocellular carcinoma

AIM:To assess the rate and risk factors for tumour seeding in a large cohort of patients.METHODS:Over an 8-year period,1436 hepatocellular carcinoma(HCC) patients with 2423 tumour nodules underwent 3015 image-guided percutaneous cryoablation sessions [1215 guided by ultrasonography and 221 by spiral computed tomography(CT)].Follow-up CT or magnetic resonance imaging was performed every 3 mo.The detailed clinical data were recorded to analyse the risk factors for seeding.RESULTS:The median follow-up time was 18(range 1-90) mo.Seeding was detected in 11 patients(0.76%) at 1-24(median 6.0) mo after cryoablation.Seeding occurred along the needle tract in 10 patients and at a distant location in 1 patient.Seeded tumours usually showed similar imaging and histopathological features to the primary HCCs.Univariate analyses identified subcapsular tumour location and direct subcapsular needle insertion as risk factors for seeding.Multivariate analysis showed that only direct subcapsular needle insertion was an independent risk factor for seeding(P = 0.017;odds ratio 2.57;95%CI:1.47-3.65).Seeding after cryoablation occurred earlier in patients with poorly differentiated HCC than those with well or moderately differentiated HCC [1.33 ± 0.577 mo vs 11.12 ± 6.896 mo;P = 0.042;95%CI:(-19.115)-(-0.468)].CONCLUSION:The risk of seeding after cryoablation for HCC is small.Direct puncture of subcapsular tumours should be avoided to minimise seeding.

心肌梗死患者基于CMR-FT评价的机械离散与QTc间期的相关性研究

目的探索心肌梗死(MI)患者基于心脏磁共振组织特征追踪技术(CMR-FT)评价的左室机械离散(LVMD)与心电参数QTc间期(校正QT间期)的相关性。方法纳入经临床及CMR确诊的MI患者,根据随访结果分为心血管主要不良事件(MACE)组和无MACE组。左室功能参数包括:左室射血分数(LVEF)、左室舒张末期容积(LVEDV)、左室收缩末期容积(LVESV)、应变参数衍生参数LVMD;心电图参数QTc间期,CMR和心电图采集时间为同一周内。采用独立样本t检验、Mann-Whitney U秩和检验及χ^(2)检验比较两组患者的基线资料、左室功能和应变参数,运用Spearman相关性分析LVMD与QTc间期、长QTc间期(QTc间期>440 ms)和正常QTc间期的相关性,再进一步分析MI后MACE组和无MACE组患者LVMD与QTc间期的相关性。结果最终纳入169例MI患者,中位随访时间为25个月,MACE组56例,无MACE组113例。两组患者的年龄、LVEF、QTc间期、LVMD差异具有统计学意义(均P<0.05)。Spearman相关性分析显示,LVMD与QTc间期(r_(s)=0.590,P<0.001)、长QTc间期(QTc间期>440 ms)(r_(s)=0.542,P<0.001)及正常QTc间期(320≤QTc间期≤440 ms)(r_(s)=0.249,P=0.033)均具有正相关。MACE组患者LVMD与QTc间期的相关性(r_(s)=0.544,P<0.001)高于无MACE组(r_(s)=0.358,P=0.001)。结论在MI患者中,CMR评价的LVMD与心电参数QTc间期和长QTc间期呈正相关,这种相关性在长QTc间期和MACE组的MI患者中更为明显,这提示LVMD随着QTc间期的延长而增加;MACE的发生风险可能与LVMD的增加和QTc间期的延长有关,这有助于对MI患者MACE风险分层更深入的认知。