Cardiac magnetic resonance visualizes acute and chronic myocardial injuries in myocarditis

Our objective was to evaluate the ability of CMR to visualize myocardial injuries over the course of myocarditis. We studied 42 patients (39 males, 3 females; age 37 ± 14 years) with myocarditis during the acute phase and after 12 ± 9 months. CMR included function analyses, T2-weighted imaging (T2 ratio), T1-weighted imaging before and after i.v. gadolinium injection (global relative enhancement; gRE), and late gadolinium enhancement (LGE). In the acute phase, the T2 ratio was elevated in 57%, gRE in 31%, and LGE was present in 64% of the patients. In 32 patients (76%) were any two (or more) out of three sequences abnormal. At follow-up, there was an increase in ejection fraction (57.4 ± 11.9% vs. 61.4 ± 7.6; P < 0.05) while both T2 ratio (2.04 ± 0.32 vs. 1.70 ± 0.28; P < 0.001) and gRE (4.07 ± 1.63 vs. 3.11 ± 1.22; P < 0.05) significantly decreased. The LGE persisted in 10 patients. Dilated cardiomyopathy was present in 3 patients and 4 patients received a defibrillator or a pacemaker. A comprehensive CMR approach is a useful tool to visualize myocardial tissue injuries over the course of myocarditis. CMR may help to differentiate acute from healed myocarditis, and add information for the differential diagnoses.     

A fast and effective method to assess myocardial hyperemia in acute myocarditis by magnetic resonance

Current cardiac magnetic resonance (CMR) quantitative signs for the diagnosis of myocarditis include myocardial edema, fibrosis and myocardial hyperemia (Hyp). Methods for the assessment of Hyp are actually complex and time-consuming. To test a simple and fast method to assess Hyp, using contrast enhancement steady state free precession (ceSSFP) technique. CMR imaging at 1.5T was performed on 39 patients with diagnosis of acute myocarditis and in 20 healthy controls. Hyp was evaluated in systolic and diastolic frames (Hyp-SYS and Hyp-DIA) as areas of myocardial hyperintensity in ceSSFP images early after gadolinium injection. Myocardial edema was evaluated using T2-STIR images. Myocardial fibrosis was assessed in conventional late gadolinium enhancement (LGE) images. A value of ≤12.1 g of Hyp-DIA was obtained as cut-off of normality in healthy controls. Using this threshold, Hyp was detected in 30 patients (77 %) with myocarditis. LGE was detected in 36 patients (92 %), and myocardial edema in 38 (97 %) patients with myocarditis A linear relation was found between Hyp-DIA and the extent of myocardial edema (R² 0.48, 95 % CI 0.47–0.85, p < 0.001) and the extent of LGE (R² 0.41, 95 % CI 0.31–0.61, p < 0.001). Patients with hyperemia had higher levels of C-reactive protein (p < 0.001), a higher extent of LGE (p < 0.05) and a larger left atrial area (p < 0.05). ceSSFP sequence at CMR is a novel and fast method to assess myocardial hyperemia in patient with acute myocarditis. Compared with non-Hyp subjects, patients with Hyp had more signs of inflammation and myocardial damage.     

多模态心脏磁共振成像在急性病毒性心肌炎中的临床价值

目的 探讨多模态心脏磁共振成像(CMR)在急性病毒性心肌炎(AVM)中的临床价值.方法 选择60例AVM患者为观察组,另选取40例健康志愿者为对照组.2组受检者均接受多模态CMR检查,并检测白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)水平.采用受试者工作特征(ROC)曲线分析多模态CMR参数在AVM诊断中...     

急性心肌梗死磁共振研究进展

急性心肌梗死是严重的心血管急症,患病率及死亡率均较高,虽然介入治疗可有效缓解部分患者的症状,但是患者的心肌危险区域、再灌注过程中的微循环损伤等与预后紧密相关。随着磁共振技术的快速发展,其在急性心肌梗死中的应用日益成熟,本文就心脏磁共振在急性心肌梗死中的最新研究进展做一综述。     

Reliability of myocardial salvage assessment by cardiac magnetic resonance imaging in acute reperfused myocardial infarction

Myocardial salvage assessed by cardiac magnetic resonance imaging (CMRI) holds promise as a surrogate endpoint in studies comparing different treatment strategies for ST-elevation myocardial infarction (STEMI). The aim of this study was to evaluate the reliability of salvaged myocardium measurements by CMRI. Twenty patients underwent CMRI on 2 consecutive days early after reperfused STEMI to assess the area at risk (AAR) on T2-weighted and final infarct size (IS) on delayed enhancement images. Myocardial salvage index (MSI) was calculated (AAR minus IS). Agreement between scans 1 and 2 for the AAR, IS and MSI were analyzed using Bland?CAltman analyses. Inter- and intraobserver reliability were assessed. Paired t testing revealed a trend for a significant difference for MSI between scans 1 and 2 (scan 1: 43.8?±?22.5; scan 2: 45.5?±?22.0; P?=?0.052). The average difference for AAR and IS between scan 1 and scan 2 was ?0.5 (upper limit of agreement 5.4% of left ventricular [LV] volume; lower limit of agreement ?6.4%LV) and 0.1%LV (upper limit of agreement 2.3%LV; lower limit of agreement ?2.1%LV). The corresponding calculated MSI measurements showed a mean bias of ?1.7 (upper limit of agreement 5.5; lower limit of agreement ?8.9). Coefficients of repeatability for interobserver variability were 3.6%LV for AAR, 2.4%LV for IS and 5.4 for MSI. Likewise, for intraobserver variability, coefficients of repeatability were 5.0%LV (AAR), 2.4%LV (IS) and 4.8 (MSI). Assessment of myocardial salvage by CMRI shows acceptable reliability. Further validation studies and trials showing the prognostic value of myocardial salvage by CMRI are needed before routine implementation as a surrogate endpoint in STEMI trials.     

Cardiac magnetic resonance in cocaine-induced myocardial damage

A 54-year-old male with history of cocaine abuse underwent trans-thoracic echocardiography that showed hyper-echogenicity of the basal segments of the septum and infero-lateral wall of the left ventricle. The patient underwent cardiac CT that reported diffuse non-obstructive CAD. Cardiac MR showed LGE patterns consistent with non-ischemic myocardial damage associated with cocaine abuse.     

磁共振特征追踪技术在急性心肌炎中的评估

目的探讨心脏磁共振特征追踪技术在射血分数(EF)保留急性心肌炎心功能受损中的评估价值。方法回顾性收集49例心肌炎病例,并招募了50例正常志愿者作为对照,利用心脏磁共振特征追踪技术,分析心肌炎、EF值保留心肌炎与对照组的心脏磁共振参数与心肌应变的变化特征。结果结果显示心肌炎组较对照组的EF(55.39%±17.55%比66.28%±5.36%)、心肌径向应变(PSR)(25.97%±11.77%比40.80%±9.68%)、圆周应变(PSC)(-16.47%±6.27%比-22.19%±2.76%)、纵向应变(PSL)(-10.49%±4.40%比-14.50%±2.56%)是下降的。EF保留心肌炎组较对照组的PSR(31.30%±7.16%比40.80%±9.68%)、PSC(-19.64%±2.44%比-22.19%±2.76%)、PSL(-12.14%±3.75%比-14.50%±2.56%)也是下降的。ROC曲线分析结果显示PSR,PSC鉴别心肌炎与正常病例的AUC最大(为0.84),其中PSR的临界值取33.61%时,敏感度为76%,特异度为80%,而PSC的临界值为-20.14%时,敏感度为73%,特异度为84%。而在区分EF保留心肌炎与正常者的能力方面,PSR的AUC值最大(为0.79),当PSR的临界值为35.82%时,敏感度为70%,特异度为75%。结论利用心脏磁共振特征特征追踪技术能发现EF保留心肌炎患者的心肌应变受损,有助于对早期心功能受损的识别与评估。     

Incremental value of cardiac deformation analysis in acute myocarditis: a cardiovascular magnetic resonance imaging study

The aim of this study was to assess cardiac deformation patterns in myocarditis applying feature tracking imaging (FTI) to cardiovascular magnetic resonance (CMR) images. Thirty-six patients (31 males) with acute myocarditis and 36 age- and gender-matched healthy volunteers were studied. CMR examinations were performed in a 1.5 T MR-scanner including late gadolinium enhancement (LGE). FTI was applied to standard cine images of long and short axis views. Global peak circumferential, longitudinal and radial systolic strains as well as long axis strain (LAS) were measured. Patients showed significantly impaired global peak circumferential (?24.4?±?4.2?% vs. ?28.8?±?3.8?%, p?<?0.0001), longitudinal (?17.6?±?4.4?% vs. ?23.8?±?3.1?%, p?<?0.0001) and radial (26.1?±?5.4?% vs. 37.9?±?7.6?%, p?<?0.0001) systolic strains. Even patients with a preserved ejection fraction (pEF, ≥55?%) had significantly reduced longitudinal (?20.0?±?4.8?% vs. ?23.8?±?3.1?%, p?<?0.01) and radial (27.7?±?5.5?% vs. 37.9?±?7.6?%, p?<?0.0001) strains. The extent of LGE in patients did not correlate to their respective strains. Regarding the differentiation between patients and controls, the addition of global peak systolic strains to ejection fraction led to a significant improvement of the logistic regression model (χ² 48.7 vs. 71.5; p?<?0.001) resulting in a high AUC of 0.98. Applying previously published reference values, 75?% or 31?% of patients with pEF showed at least one strain value or a LAS, which fell below the limit of 1 or respectively 2 standard deviations from the reference mean value. Cardiac strains measured by CMR–FTI are significantly impaired in patients with acute myocarditis even in those with pEF. Therefore, strain assessment may improve the diagnostic accuracy of CMR for myocarditis.     

心脏磁共振及实验室检查联合评估心肌缺血

目的探讨心脏磁共振(cardiac magnetic resonance imaging,CMR)及实验室检查指标在评估心肌缺血中的临床价值。材料与方法 7只巴马小型猪成功构建心肌缺血模型,分别于术前、术后2 h、12 h、24 h、48 h、72 h、1周、2周、3周、4周检测心肌酶谱、肌钙蛋白、肌红蛋白等实验室检查指标,并于上述各时段行CMR检查,最终行病理检查。结果巴马猪术后2 h肌钙蛋白及肌红蛋白即明显升高,分别为[(0.005±0.002)、(0.338±0.768) ng/ml,P<0.05],72 h内诸心肌损伤标志物变化显著(均P<0.05),提示心肌损伤,1周后趋于平稳;CMR示缺血早期T2WI黑血序列显示心肌水肿,即危险心肌,电影(cine)序列出现局部室壁运动异常,首过灌注术后2 h即出现灌注减低或缺损,术后24 h部分心肌节段出现延迟强化,透壁程度随着缺血时间的延长,不断增加,最终经病理证实心肌坏死、纤维化。4周CMR所测心功能指标较术前显著降低(左室射血分数%:分别为62.71±8.33、45.97±6.37,P<0.05)。结论心肌酶谱及肌钙蛋白、肌红蛋白对心肌损伤有提示意义,CMR可确切地显示心肌缺血微观组织学变化,联合评估可为急性冠脉综合症提供详细的诊断信息并指导治疗。     

Diagnosis of viral myocarditis by cardiac magnetic resonance and viral genome detection in peripheral blood

In patients with acute myocarditis, viral genome can be detected in plasma and peripheral leukocytes. Its relationship with active myocardial inflammation, however, is not well understood. Myocardial edema as a feature of inflammation and myocardial necrosis or fibrosis can be frequently observed in patients with acute myocarditis by cardiovascular magnetic resonance (CMR). We assessed the association of viral genome presence in peripheral blood samples with myocardial edema and irreversible injury. We examined consecutive patients with clinically suspected myocarditis after an episode of viral illness. State-of-the-art methods were used for detecting myocardial edema and irreversible injury using CMR and viral genome applying reverse transcribed, nested polymerase chain reaction in peripheral blood samples. The specificity of viral amplification products was confirmed by automatic DNA sequencing. Of a total of 55 patients (53.5 ± 15.6 years), 21 were positive for viral genome in peripheral leukocytes. Interestingly, 18 (86 %) of these patients also showed global myocardial edema, as compared to only 7/34 (21 %) without PCR evidence for viral genome. The overall agreement between CMR criteria for edema and viral PCR was 84 %. In contrast, there was no significant relationship of viral genome presence with myocardial necrosis or scars. In patients with clinically suspected myocarditis, myocardial edema but not irreversible myocardial injury is associated with the presence of viral genome in peripheral blood.     

Evaluation of acute coronary syndromes by cardiac magnetic resonance imaging

The use of cardiovascular magnetic resonance (CMR) imaging for the evaluation of patients with acute chest pain and acute coronary syndromes has great potential. The strength of CMR relies on its ability to provide information on anatomy, physiology, and function in a single scanning session in a noninvasive manner without the need for iodinated contrast, radiation, or the need to undergo invasive procedures. Specifically, with regard to imaging patients with acute chest pain and/or myocardial infarction (MI), CMR has the ability to qualitatively and quantitatively evaluate global and regional right and left ventricular systolic functions, myocardial edema, myocardial perfusion, and myocardial infarct size and transmurality/viability. This review will focus on CMR imaging for the following applications: (1) imaging for the evaluation of ventricular function and infarct size in patients with acute chest pain and/or acute MI, (2) for triage and prognosis of patients presenting to the emergency department with acute chest pain, (3) for evaluating patients after sustaining an acute MI, and (4) for stem cell research.     

Prognosis of early pre-discharge and late left ventricular dilatation by cardiac magnetic resonance imaging after acute myocardial infarction

The International Journal of Cardiovascular Imaging - To study the long-term prognosis of early pre-discharge and late left ventricular (LV) dilatation in patients with first ST-elevation...     

心脏磁共振可评估急性心肌梗死患者的早期心功能状态

目的  探讨心脏磁共振对急性心肌梗死患者早期心功能状态评估价值。方法  选择2022年6月~2022年12月在我科住院并确诊的急性ST段抬高型心肌梗死患者24例,男性22例,女性2例,年龄55.3±11.3岁。所有患者均在入院后行冠状动脉介入手术,并在术后5~7 d行心脏磁共振检查。应用电影成像技术分析心功能状态、是否存在反向运动和室壁瘤;组织追踪技术分析心肌各节段的应变能力;延迟强化技术分析心肌梗死部位、梗死面积大小和是否存在微循环障碍。结果梗死节段心肌应变分析显示：24例患者中,21例患者径向应变下降,18例患者周向应变下降,21例患者纵向应变下降,16例患者三向应变均下降;整体心肌应变分析显示：15例患者径向应变下降,10例患者周向应变下降,20例患者纵向应变下降,9例患者三向应变均下降;梗死节段心肌平均径向应变和周向应变低于整体心肌平均径向应变和周向应变（P < 0.05）,梗死节段与整体心肌纵向应变的差异无统计学意义（P > 0.05）。13例患者出现心肌反向运动;左室射血分数（LVEF）下降者10例;LVEF未下降的14例中,心肌反向运动6例,梗死节段三向心肌应变下降6例,梗死区内微循环障碍7例,NT-proBNP水平升高7例。出现反向运动组患者LVEF、梗死节段心肌和整体心肌平均周向应变、纵向应变均小于未出现反向运动组患者（P < 0.05）。相关性分析显示：LVEF与心肌整体应变、梗死节段应变和左房射血分数呈正相关关系,与心肌梗死面积、左室收缩末期容积/体表面积比值、NT-proBNP水平和Genisini评分呈负相关关系（P < 0.05）。二元Logistic回归显示,梗死节段纵向应变的降低可以独立预测患者是否出现心肌反向运动。结论  心脏磁共振技术可以多角度评价心功能状态,对急性心肌梗死患者术后早期心功能评估、治疗和干预,改善患者的预后提供参考依据。     

Regional functional recovery after acute myocardial infarction: a cardiac magnetic resonance long-term study

We sought to analyze the trend of functional recovery after successful reperfused ST-elevation myocardial infarction (STEMI) in an optimally treated patient group over a 14?month follow-up in relation to ischemia-time and the presence of microvascular obstruction (MVO). First-pass perfusion-, cine- and late enhancement (LE)- cardiac MR were performed in 40 patients (33 male and 7 female, 54.8?±?12.3?years) within 6?days as well as 4 and 14?months after successful primary percutaneous coronary intervention for STEMI. Significant recovery of segmental wall thickening (SWT %) occurred exclusively in infarcted segments reperfused within 4?h after symptom onset (group 1 with pain-to-balloon time <2?h: 59?±?4 to 70?±?4%; P?相似文献   

Electrocardiographic findings of acute organophosphate poisoning

In this study, we evaluated 85 patients who presented to our Emergency Department with organophosphate (OP) poisoning and discuss their associated electrocardiographic (ECG) abnormalities. Over a period of 3 years, 85 patients with OP poisoning were included in this retrospective study. ECG analysis included the rate, rhythm, ST-T abnormalities, conduction defects, and measurement of PR and QT intervals. The mean age was 32.2 +/- 14.9 years. Sixty percent of the patients were female. The mean corrected QT interval (QTc interval) was 0.435 +/- 0.052 s. Prolongation of the QTc interval (55.5%) was the most common ECG abnormality, followed by sinus tachycardia (31.8%). Elevation of the ST segment and low amplitude T waves were seen in 15 cases (17.6%). Patients with OP poisoning might reveal ECG abnormalities such as QTc interval prolongation or non-specific ST-T changes. QTc interval prolongation cannot be used as a unique predictive factor in determining short-term prognosis in OP poisoning. We found no clear relation between OP poisoning-related malignant ventricular dysrhythmia and QTc interval.     

Cardiovascular magnetic resonance predictors of clinical outcome in patients with suspected acute myocarditis

Background

The natural history of acute myocarditis (AM) remains highly variable and predictors of outcome are largely unknown. The objectives were to determine the potential value of various cardiovascular magnetic resonance (CMR) parameters for the prediction of adverse long-term outcome in patients presenting with suspected AM.

Methods

In a single-centre longitudinal prospective study, 203 routine consecutive patients with an initial CMR-based diagnosis of AM (typical Late Gadolinium Enhancement, LGE) were followed over a mean period of 18.9 ± 8.2 months. Various CMR parameters were evaluated as potential predictors of outcome. The primary endpoint was defined as the occurrence of at least one of the combined Major Adverse Clinical Events (MACE) (cardiac death or aborted sudden cardiac death, cardiac transplantation, sustained documented ventricular tachycardia, heart failure, recurrence of acute myocarditis, and the need for hospitalization for cardiac causes).

Results

The vast majority of patients (N = 143,70 %) presented with chest pain, mild to moderate troponin elevation and ST-segment or T wave abnormalities. Various CMR parameters were evaluated on initial CMR performed 3 ± 2 days after acute clinical presentation (LV functional parameters, presence/extent of edema on T2 CMR, and extent of late gadolinium enhancement lesions). Out of the 203 patients, 22 experienced at least one major cardiovascular event (10.8 %) during follow-up for a total of 31 major cardiovascular events. Among all CMR parameters, the only independent CMR predictor of adverse clinical outcome by multivariate analysis was an initial alteration of LVEF (p = 0.04).

Conclusions

In routine consecutive patients without severe hemodynamic compromise and a CMR-based diagnosis of AM, various CMR parameters such as the presence and extent of myocardial edema and the extent of late gadolinium-enhanced LV myocardial lesions were not predictive of outcome. The only independent CMR predictor of adverse clinical outcome was an initial alteration of LVEF.