心脏磁共振在肥厚型心肌病心肌应变力分析中的应用进展

肥厚型心肌病(hypertrophic cardiomyopathy,HCM)是一种遗传性心肌病,临床表型多样,不良心血管事件发生率较高.心脏磁共振以其多角度多参数等优势在临床中应用逐渐广泛,近年来兴起的心脏磁共振心肌应变力分析能够早期评估心肌运动功能,对于早期诊断和预后有重要价值.笔者就心肌应变力分析在肥厚型心肌病的...     

碎裂QRS波对扩张型心肌病患者预后的预测价值

目的:探讨碎裂QRS波(f QRS)对扩张型心肌病(DCM)患者预后的预测价值。方法:对166例DCM患者和100例健康对照者进行12导联心电图检查,根据患者是否存在f QRS分为f QRS组和无f QRS组,比较f QRS在DCM组和健康对照组的发生率,比较DCM患者中f QRS组和无f QRS组心血管事件的发生率,并进行多变量Cox回归分析。结果:DCM组f QRS发生率显著高于对照组(P<0.01);DCM患者中f QRS组心源性猝死、非猝死性心性死亡、恶性心律失常、左室射血分数(LVEF)降低和严重房室传导阻滞发生率显著高于无f QRS组(P<0.01~0.001);多变量Cox回归分析显示:f QRS对DCM的影响有显著统计学意义(P<0.01)。结论:f QRS可成为心电图诊断DCM的新指标,是DCM患者心血管事件的预测因子。     

心电图碎裂QRS波对冠心病的诊断价值

目的 探讨心电图碎裂QRS波对冠心病的诊断价值.方法 选择2019年1月至2019年12月济源市人民医院收治的300例疑似冠心病(CAD)患者为研究对象,均行冠状动脉造影术及心电图检查,将冠状动脉造影术的结果作为金标准,比较两组患者心电图破裂QRS波的诊断效能,比较患者间的血管支数、罪犯血管、狭窄程度心电图破裂QRS检...     

碎裂QRS与特发性扩张型心肌病预后关系研究

目的探讨碎裂ORS与特发性扩张型心肌病患者预后的关系。方法85例特发性扩张型心肌病患者根据常规心电图检查结果分为碎裂QRS组41例和非碎裂QRS组44例,随访2～33（16．5士9．4）个月,比较2组患者全因病死率和室性心律失常发生率。结果8例死亡,5例室性心律失常;碎裂QRS组全因病死率和室性心律失常发生率高于非碎裂QRS组（P〈0．05）;Kaplan-Meier生存分析碎裂QRS组生存率低于非碎裂QRS组（P〈0．05）;多变量C0z回归分析显示,碎裂QRS是特发性扩张型心肌病全因死亡和室性心律失常的预测因子（OR=1．182,95％CI：1．036～2．910,P=0．038）。结论碎裂QRS与特发性扩张型心肌病的不良预后有关,碎裂QRS对特发性扩张型心肌病患者全因死亡和室性心律失常有较高预测价值。     

碎裂QRS波群的研究现状

碎裂QRS波群(fragmented QRS complexes,fQRS)在相关疾病的预测和防治中具有明显的优势,已成为近年来备受关注的一项新的心源性猝死的预敬指标,现对其概念病理生理、发生机制及临床意义进行综述.     

心脏磁共振心肌延迟强化对肥厚型梗阻性心肌病射频消融疗效及预后的影响

目的:探讨心脏磁共振心肌延迟强化对肥厚型梗阻性心肌病(HOCM)射频消融治疗疗效及预后的影响。方法:研究连续纳入2020年4月—2021年7月在浙江大学医学院附属第一医院确诊HOCM患者26例,进行经室间隔射频消融治疗,术前均行心脏磁共振增强检查,由有丰富经验的放射科医生观察心脏磁共振延迟强化图像判断心肌有无延迟强化,将其分为延迟强化组(LGE+组)及无延迟强化组(LGE-组),其中LGE+组患者14例,LGE-组患者12例。收集患者术前及术后的超声资料,对比左室流出道压差变化,并随访术后一年内的并发症。所有患者均采用自身对照,计量资料比较采用配对t检验。结果:26例患者中男性17例,女性9例,年龄22～75 (51.38±13.20)岁。LGE+组消融前后左室流出道压差(LVOTG)[静息状态(63.29±32.40) mmHg vs (39.41±36.51) mmHg,P=0.092;运动激发后(115.45±45.36) mmHg vs (54.00±40.10) mmHg,P-0.002]。LGE-组患者消融前后LVOTG[静息状态(66.51±58.89)mmHg vs (...     

碎裂QRS波对陈旧性心肌梗死的诊断价值

目的:分析心电图碎裂QRS波对陈旧性心肌梗死的诊断价值。方法:选择78例经冠脉造影诊断为冠心病的患者,应用心肌核素断层显像技术识别心肌缺血和心肌瘢痕,并以核素显像作对照,观察碎裂QRS波、病理性Q波、碎裂QRS波合并病理性Q波对陈旧性心肌梗死诊断的敏感性、特异性、准确性、阳性预测值和阴性预测值。结果:78例患者中有65例碎裂QRS波、病理性Q波,碎裂QRS波合并病理性Q波与无灌注的心肌瘢痕有关,2例碎裂QRS波跨越冠脉心肌供血区域分布,有11例显示心肌大范围灌注不良,提示心肌缺血;碎裂QRS波诊断陈旧性心肌梗死的敏感性(81.8%)明显高于病理性Q波(37.5%)(P<0.001),特异性(85.7%)低于病理性Q波(96.2%)(P<0.05),结合碎裂QRS波和病理性Q波,对陈旧性心肌梗死的诊断具有更高的敏感性(94.4%)(P<0.001),碎裂QRS波的诊断效率(0.83)明显高于病理性Q波(0.67)(P<0.001)。结论:碎裂QRS波对陈旧性心肌梗死有重要的诊断价值,其诊断效率明显高于病理性Q波,碎裂QRS波结合病理性Q波可提高诊断的敏感性和准确性。     

心电图碎裂QRS波与病理性Q波联合诊断急性心肌梗死的临床价值

目的 分析心电图碎裂QRS波与病理性Q波联合诊断急性心肌梗死(AMI)的临床价值.方法 将我院2017年1月至2019年12月收治的112例AMI患者纳入本次研究,所有患者均给予心电图检查.以病理诊断结果为金标准,比较碎裂QRS波、病理性Q波单一及联合诊断AMI的准确度、灵敏度、特异度、阳性预测值与阴性预测值.结果 联...     

心脏磁共振参数列线图模型对扩张型心肌病老年患者不良心血管事件的预测价值

目的 探究心脏磁共振（CMR）参数列线图模型对扩张型心肌病（DCM）老年患者主要不良心血管事件（MACE）的预测价值。 方法 回顾性分析2017年7月~2020年7月在武汉科技大学附属孝感医院接受CMR检查的DCM老年患者173例,将患者按6:4的比例随机分为训练集（n=104）及测试集（n=69）。通过LASSO回归及多因素Cox回归筛选潜在预测因子,以此构建DCM患者MACE列线图预测模型。通过校准曲线、ROC曲线、决策曲线分析法、Kaplan-Meier生存分析对列线图模型进行评估及验证。 结果 中位随访时间为29.7（16.4,45.4）月。随访结束时,59例（34.1%）患者发生MACE。LASSO回归及交叉验证筛选出9个潜在预测因子。多因素Cox回归分析结果显示,纽约心功能分级Ⅲ~Ⅳ级、N末端-脑钠肽前体、β受体阻断药、CMR晚期钆增强、左心室整体纵向应变是DCM患者发生MACE风险因子,并以此构建列线图预测模型。在训练集和测试集中,校准图显示列线图预测1年、3年生存率与实际生存率一致性较好。训练集1年、3年生存预测ROC曲线下面积分别为0.850（95%CI：0.748~0.953）、0.853（95% CI：0.797~0.909）,测试集1年、3年生存预测ROC曲线下面积分别为0.858（95% CI：0.758~0.959）、0.887（95% CI：0.816~0.958）。决策曲线分析结果显示列线图模型的临床净获益率较高。Kaplan-Meier生存分析结果示,预测模型高风险组患者较低风险组生存概率降低（P＜0.05）。 结论 本研究通过临床和CMR特征参数构建了DCM老年患者MACE发生列线图预测模型,该模型具有较好校准度、区分度及临床应用价值。     

Accuracy and reproducibility of semi-automated late gadolinium enhancement quantification techniques in patients with hypertrophic cardiomyopathy

Background

The presence and extent of late gadolinium enhancement (LGE) has been associated with adverse events in patients with hypertrophic cardiomyopathy (HCM). Signal intensity (SI) threshold techniques are routinely employed for quantification; Full-Width at Half-Maximum (FWHM) techniques are suggested to provide greater reproducibility than Signal Threshold versus Reference Mean (STRM) techniques, however the accuracy of these approaches versus the manual assignment of optimal SI thresholds has not been studied. In this study, we compared all known semi-automated LGE quantification techniques for accuracy and reproducibility among patients with HCM.

Methods

Seventy-six HCM patients (51 male, age 54 ± 13 years) were studied. Total LGE volume was quantified using 7 semi-automated techniques and compared to expert manual adjustment of the SI threshold to achieve optimal segmentation. Techniques tested included STRM based thresholds of >2, 3, 4, 5 and 6 SD above mean SI of reference myocardium, the FWHM technique, and the Otsu-auto-threshold (OAT) technique. The SI threshold chosen by each technique was recorded for all slices. Bland-Altman analysis and intra-class correlation coefficients (ICC) were reported for each semi-automated technique versus expert, manually adjusted LGE segmentation. Intra- and inter-observer reproducibility assessments were also performed.

Results

Fifty-two of 76 (68%) patients showed LGE on a total of 202 slices. For accuracy, the STRM >3SD technique showed the greatest agreement with manual segmentation (ICC = 0.97, mean difference and 95% limits of agreement = 1.6 ± 10.7 g) while STRM >6SD, >5SD, 4SD and FWHM techniques systematically underestimated total LGE volume. Slice based analysis of selected SI thresholds similarly showed the STRM >3SD threshold to most closely approximate manually adjusted SI thresholds (ICC = 0.88). For reproducibility, the intra- and inter-observer reproducibility of the >3SD threshold demonstrated an acceptable mean difference and 95% limits of agreement of −0.5 ± 6.8 g and −0.9 ± 5.6 g, respectively.

Conclusions

FWHM segmentation provides superior reproducibility, however systematically underestimates total LGE volume compared to manual segmentation in patients with HCM. The STRM >3SD technique provides the greatest accuracy while retaining acceptable reproducibility and may therefore be a preferred approach for LGE quantification in this population.     

Unveiling nonischemic cardiomyopathies with cardiac magnetic resonance

Cardiomyopathy is defined as a heterogeneous group of myocardial disorders with mechanical or electrical dysfunction. Identification of the etiology is important for accurate diagnosis, treatment and prognosis, but continues to be challenging. The ability of cardiac MRI to non-invasively obtain 3D-images of unparalleled resolution without radiation exposure and to provide tissue characterization gives it a distinct advantage over any other diagnostic tool used for evaluation of cardiomyopathies. Cardiac MRI can accurately visualize cardiac morphology and function and also help identify myocardial edema, infiltration and fibrosis. It has emerged as an important diagnostic and prognostic tool in tertiary care centers for work up of patients with non-ischemic cardiomyopathies. This review covers the role of cardiac MRI in evaluation of nonischemic cardiomyopathies, particularly in the context of other diagnostic and prognostic imaging modalities.     

Late hyperenhancement in gadolinium-enhanced magnetic resonance imaging: comparison of hypertrophic cardiomyopathy patients with and without nonsustained ventricular tachycardia

Aim To assess the extent of hyperenhancement in hypertrophic cardiomyopathy (HCM) patients with nonsustained ventricular tachycardia (NSVT) in comparison to patients without NSVT. Design In HCM patients, NSVT in Holter monitoring is a risk factor for sudden cardiac death; however, its positive predictive value is low. Varying risk of sudden death related to NSVT may be dependent on the heterogeneous extent of the arrhythmogenic substrate, which seems to be visible as hyperenhancement in gadolinium-enhanced magnetic resonance imaging (MRI). Methods Hyperenhancement was assessed in 47 HCM patients (30 males and 17 females, mean age 42 ± 12 years): 32 patients had NSVT, 15 patients had no NSVT. The extent of hyperenhancement was calculated by software and expressed as a mass. Results In HCM patients with NSVT 97% had some extent of hyperenhancement on MRI, ranging from 1 to 76 g. The mean mass of hyperenhanced myocardium was 19 ± 18 g (8.1 ± 7.6% of total left ventricular mass). In HCM patients without NSVT, a significantly lower percentage of patients (60%) had hyperenhancement (P < 0.05). However, the amount of hyperenhanced myocardium was not significantly different (13 ± 19 g, 6.3 ± 9.1% of total left ventricular mass; P < 0.05). Conclusions Hyperenhancement was visible in almost all HCM patients with NSVT (97%) and in a significantly lower percentage of patients without NSVT (60%). Whether this finding explains the increased risk of sudden death in case of NSVT is not clear, since the extent of hyperenhancement was not significantly different between the two groups.     

Characterization of patients with acute chest pain using cardiac magnetic resonance imaging

Aims  The purpose of this study was to evaluate whether CMRI provides characteristic findings in patients with acute chest pain suffering from ST-elevation-myocardial infarction (STEMI), non-ST-elevation myocardial infarction (NSTEMI), acute myocarditis or Tako-tsubo cardiomyopathy. Patients and methods  230 consecutive patients with acute chest pain underwent cardiac catheterization followed by CMRI within median 5 days. Patients were classified to suffer from STEMI (n = 102), NSTEMI (n = 89), acute myocarditis (n = 27), or Tako-tsubo cardiomyopathy (n = 12) on the synopsis of all clinical data. Wall motion abnormalities, late enhancement (LE), persistent microvascular obstruction as well ventricular volumes and functions were assessed by CMRI. Results  Right and left ventricular volumes were significantly different between the groups and values were highest in patients with acute myocarditis. Wall motion abnormalities were observed in 100% of STEMI, 75% of NSTEMI, 67% of acute myocarditis and 100% of Tako-tsubo patients. There was a characteristic pattern of abnormal wall motion focused on midventricular-apical segments in patients with Tako-tsubo cardiomyopathy, depending on the culprit vessel in patients with STEMI/NSTEMI and with a random distribution in patients with acute myocarditis. LE was mainly subendocardial or transmural in patients with STEMI (93.2%) or NSTEMI (62.9%). LE was diffuse, intramural or subepicardial in patients with acute myocarditis. No LE was observed in patients with Tako-tsubo cardiomyopathy. Persistent microvascular obstruction was only visualized in patients with STEMI (33%) or NSTEMI (6%). Conclusions  Cardiac magnetic resonance imaging provides characteristic patterns of LE, persistent microvascular obstruction and wall motion abnormalities that allow a differentiation between patients with acute chest pain from coronary and non-coronary origin. Supported in part by an unrestricted grant of Philips Medical Systems Best, The Netherlands, and Hamburg, Germany. For paper handling: jochen.woehrle@uniklinik-ulm.de     

Coronary microvascular ischemia in hypertrophic cardiomyopathy - a pixel-wise quantitative cardiovascular magnetic resonance perfusion study

Background

Microvascular dysfunction in HCM has been associated with adverse clinical outcomes. Advances in quantitative cardiovascular magnetic resonance (CMR) perfusion imaging now allow myocardial blood flow to be quantified at the pixel level. We applied these techniques to investigate the spectrum of microvascular dysfunction in hypertrophic cardiomyopathy (HCM) and to explore its relationship with fibrosis and wall thickness.

Methods

CMR perfusion imaging was undertaken during adenosine-induced hyperemia and again at rest in 35 patients together with late gadolinium enhancement (LGE) imaging. Myocardial blood flow (MBF) was quantified on a pixel-by-pixel basis from CMR perfusion images using a Fermi-constrained deconvolution algorithm. Regions-of-interest (ROI) in hypoperfused and hyperemic myocardium were identified from the MBF pixel maps. The myocardium was also divided into 16 AHA segments.

Results

Resting MBF was significantly higher in the endocardium than in the epicardium (mean ± SD: 1.25 ± 0.35 ml/g/min versus 1.20 ± 0.35 ml/g/min, P < 0.001), a pattern that reversed with stress (2.00 ± 0.76 ml/g/min versus 2.36 ± 0.83 ml/g/min, P < 0.001). ROI analysis revealed 11 (31%) patients with stress MBF lower than resting values (1.05 ± 0.39 ml/g/min versus 1.22 ± 0.36 ml/g/min, P = 0.021). There was a significant negative association between hyperemic MBF and wall thickness (β = −0.047 ml/g/min per mm, 95% CI: −0.057 to −0.038, P < 0.001) and a significantly lower probability of fibrosis in a segment with increasing hyperemic MBF (odds ratio per ml/g/min: 0.086, 95% CI: 0.078 to 0.095, P = 0.003).

Conclusions

Pixel-wise quantitative CMR perfusion imaging identifies a subgroup of patients with HCM that have localised severe microvascular dysfunction which may give rise to myocardial ischemia.     

Late gadolinium enhancement CMR in patients with tachycardia-induced cardiomyopathy caused by idiopathic ventricular arrhythmias

Background: Idiopathic ventricular arrhythmias in the form of monomorphic premature ventricular contractions (PVC) and/or ventricular tachycardia (VT) can cause tachycardia‐induced cardiomyopathy (TICMP). The aim of this study was to determine the prevalence of late gadolinium enhancement (LGE) in patients with TICMP caused by idiopathic ventricular arrhythmias. Methods: The study population consisted of 298 consecutive patients (174 F/124 M; mean age 45 ± 17 years) with frequent PVCs and/or VT. TICMP was defined as left ventricular ejection fraction (LVEF) of ≤50% in the absence of any detectable underlying heart disease and improvement of LVEF ≥15% after effective treatment of index ventricular arrhythmia. Results: Twenty‐seven (9.1%) patients found to have LVEF ≤50% and diagnosed as presumptive TICMP. Improvement in LVEF after effective treatment of index ventricular arrhythmia was observed in 22 of 27 patients (TICMP group; mean PVC burden of 30.8 ± 9.9%). LVEF did not improve in five of 27 patients (primary cardiomyopathy group; mean PVC burden of 28.8 ± 10.1%). LGE‐cardiac magnetic resonance (CMR) imaging was performed in 19 of 22 patients with TICMP and one patient (5%) had LGE. All five patients with primary cardiomyopathy underwent LGE‐CMR imaging and four patients (80%) had LGE. Conclusions: LGE is a rare finding in patients with TICMP caused by idiopathic ventricular arrhythmias. LGE‐CMR can be used in the diagnostic work‐up of patients with TICMP. Further prospective studies are required to determine the role of LGE‐CMR in predicting the recovery of left ventricular systolic dysfunction in patients with presumptive TICMP. PACE 2012; 35:465–470)     

心脏磁共振特征追踪技术在肥厚型心肌病中的应用进展

肥厚型心肌病(HCM)继发心脏各心腔结构及心肌功能异常是引起心房颤动、心力衰竭及心源性猝死等不良结局的重要因素.近年心脏磁共振特征追踪(CMR-FT)技术广泛用于HCM,可较好地量化各心腔整体及局部心肌功能,评估心脏舒张及收缩功能,现已成为定量评估心血管功能的有效影像学方法之一.本文对CMR-FT用于HCM研究进展进行...