Echocardiography of dilated cardiomyopathy in children

Echocardiography is useful and reliable in the diagnosis and management of children with dilated cardiomyopathy. M-mode echocardiography provides quantitative information of left ventricular and left atrial dimensions and left ventricular wall thickness. Left ventricular function including shortening fraction, mean velocity of circumferential fiber shortening (V cf), systolic time intervals, left ventricular wall thickening and thinning rate, isovolumic contraction time, and wall stress can be derived from M-mode study. Left ventricular and left atrial dimensions are usually 1.5 times normal. Left ventricular systolic function is markedly reduced. Shortening fraction can be easily obtained and is the most informative index for assessing the severity of illness. Very low shortening fraction at presentation and follow-up (12-15%) is a poor prognostic sign. Two-dimensional echocardiography is valuable for excluding valvular lesion or coronary artery anomaly and detection of intracardiac thrombus. The left ventricular free wall is usually more severely affected than the ventricular septum as seen by two-dimensional echocardiography.     

扩张型心肌病的治疗进展

扩张型心肌病(DCM)的基本治疗包括抗心力衰竭、心律失常及预防血栓栓塞等并发症。β-受体阻滞剂、血管紧张素转换酶抑制剂与血管紧张素受体拮抗剂及醛固酮受体拮抗剂可降低DCM心力衰竭的死亡率。胺碘酮对室性心律失常的治疗是安全有效的,埋藏式心脏复律除颤器(ICD)则可减少猝死,但ICD是否可在DCM的一级预防中应用尚存争议。心脏再同步治疗为部分心力衰竭患者提供了新的治疗方法。外科治疗主要适用于难以治疗的、晚期的DCM心力衰竭患者。他汀类药物及已酮可可碱、免疫球蛋白的使用可短期改善DCM患者的心功能。     

Baseline scintigraphic abnormalities by myocardial perfusion imaging predict echocardiographic response to cardiac resynchronization therapy in nonischemic cardiomyopathy

BACKGROUND: Significant myocardial scar in the posterolateral left ventricle (LV) has been associated with a diminished response to cardiac resynchronization therapy (CRT) in patients with coronary artery disease, but the effects of resting perfusion abnormalities in nonischemic cardiomyopathy (NICM) are yet to be described. HYPOTHESIS: We sought to characterize the effect of myocardial perfusion abnormalities upon echocardiographic outcomes of CRT in patients with NICM. METHODS: Twenty-one patients (mean age 64.4 +/- 13.3; 71.4% male; mean left ventricular ejection fraction [LVEF] 20.2 +/- 6.9%) with NICM who underwent CRT implantation and Thallium-201 single positron emission computed tomography (SPECT) myocardial perfusion imaging (MPI) were included. MPI studies were read quantitatively, assigning each of 17 myocardial segments a perfusion score (0-4) and cumulatively generating a summed perfusion score (SPS). The LV lead position was determined by chest radiography. Echocardiograms were performed both before and after (median 12 mo) CRT in 15 patients. RESULTS: Echocardiographic response, defined as > or = 15% relative increase in LVEF, was documented in 8 (53.3%) of 15 patients. All patients (5/5) with an SP < or =6 responded to CRT, whereas only 30.0% (3/10) with an SPS > or = 6 responded (odds ratio 3.33 [95% confidence interval {CI} 1.29-8.59]; p = 0.01). All nonresponders had inferior perfusion defects. Defect density adjacent to the LV lead tip had little demonstrable effect upon CRT efficacy. CONCLUSIONS: The presence of significant myocardial perfusion defects negatively influences echocardiographic response to CRT in NICM. These findings warrant prospective confirmation and histopathological correlation with explanted hearts.     

Intra-cardiac distribution of late gadolinium enhancement in cardiac sarcoidosis and dilated cardiomyopathy

Cardiac involvement of sarcoid lesions is diagnosed by myocardial biopsy which is frequently false-negative,and patients with cardiac sarcoidosis(CS) who have impaired left ventricular(LV) systolic function are sometimes diagnosed with dilated cardiomyopathy(DCM).Late gadolinium enhancement(LE) in magnetic resonance imaging is now a critical finding in diagnosing CS,and the novel Japanese guideline considers myocardial LE to be a major criterion of CS.This article describes the value of LE in patients with CS who have impaired LV systolic function,particularly the diagnostic and clinical significance of LE distribution in comparison with DCM.LE existed at all LV segments and myocardial layers in patients with CS,whereas it was localized predominantly in the midwall of basal to mid septum in those with DCM.Transmural(nodular),circumferential,and subepicardial and subendocardial LE distribution were highly specific in patients with CS,whereas the prevalence of striated midwall LE were high both in patients with CS and with DCM.Since sarcoidosis patients with LE have higher incidences of heart failure symptoms,ventricular tachyarrhythmia and sudden cardiac death,the analyses of extent and distribution of LE are crucial in early diagnosis and therapeutic approach for patients with CS.     

扩张型心肌病患儿心率变异改变及其与心脏大小和功能的关系

目的探讨扩张型心肌病（DCM）患儿心率变异（HRV）改变及其与心脏大小和收缩舒张功能的相关性。方法对30例DCM患儿（DCM组）和30例健康儿童（对照组）行24h动态心电图检查,并记录HRV指标（SDNN、SDANN、SDNN index、RMSSD、PNN50、TP、LF、HF、LF／HF）;同时行超声心动图检查,测量左室舒张末期内径（LVED）、左房舒张末期内径（LAED）、左心室射血分数（LVEF）、短轴缩短率（LVFS）和二尖瓣E／A峰比值,并分析这两类指标之间的相关性。结果DCM组HRV指标除LF／HF较对照组升高外,其余均较对照组明显降低;SDNN与LAED、LVEF、LVFS和E／A呈中度相关,其余指标与心脏大小和收缩舒张功能无明显的相关性。结论DCM患儿存在明显的自主神经平衡失调,主要表现为迷走神经张力减退,交感神经的相对激活;HRV与心脏大小和收缩舒张功能指标相对独立,其作为一无创性检测指标,可从一个侧面反映DCM患儿的预后,将它们结合起来能更好地指导临床。     

左旋卡尼汀治疗扩张型心肌病的疗效观察

目的观察左旋卡尼汀治疗扩张型心肌病（DCM）的临床疗效。方法符合WHO/ISFC诊断标准的DCM患者56例,随机分为对照组（26例）,给予硝酸酯类、血管紧张素转换酶抑制剂、安体舒通和洋地黄制剂等常规治疗;左旋卡尼汀（L-CN,商品名：雷卡）组（30例）,除上述常规治疗外加用国产L-CN3.0g,21d为一疗程。测定两组患者治疗前后血浆游离卡尼汀（f-CN）浓度,取30例单纯室上速患者血浆作为健康对照组;疗程始末行12导联心电图、24h动态心电图分析。结果与健康组相比,两组患者治疗前血浆f-CN浓度均降低;给予L-CN治疗后,L-CN组患者血浆f-CN显著升高;L-CN组和对照组患者的临床总有效率、室性早搏总有效率、短阵室速总有效率分别为86.7%vs64.4%、76.2%vs42.1%、71.4%vs41.7%,差异有统计学意义（P〈0.05）。结论本研究结果表明DCM患者体内存在肉碱缺失,补充外源性L-CN可升高患者血浆L-CN浓度,使患者临床症状及心律失常明显改善。表明L-CN是辅助治疗DCM的有效药物之一。     

Impaired Systolic torsion in dilated cardiomyopathy: Reversal of apical rotation at mid-systole characterized with magnetic resonance tagging method

Abstract Left ventricular (LV) torsion plays an important role in squeezing the blood out of the heart. To characterize the systolic torsion in LV dysfunction, we studied using magnetic resonance imaging myocardial tagging method in 26 subjects: 17 patients with dilated cardiomyopathy (DCM, LV ejection fraction [EF], 27 ± 8%) and 9 healthy control subjects. Grid-tagged LV short-axis cine images were acquired at base, mid and apex levels. Tag-intersections were tracked during the systole, thereby determining rotation angle (positive indicated clockwise from the apex). Peak torsion was defined as the maximum difference in rotation angle between the base and apex. Time to peak torsion was expressed as % systole by dividing the time by a total systolic time. Amplitude of the rotation at peak was less in DCM than in controls at both the base (0.1 ± 2.9 vs. 2.6 ± 1.6°, P < 0.05) and apex (−5.9 ± 5.3 vs. −11.2 ± 2.5°, P < 0.01). Amplitude of peak torsion was then less in DCM than in controls (6.1 ± 3.4 vs. 13.6 ± 2.5°, P < 0.001), and the timing of peak was earlier (66 ± 22 vs. 104 ± 16% systole, P < 0.001). The amplitude of peak torsion was correlated with LVEF (r=0.74, P < 0.001). In conclusion, amplitude of systolic torsion was impaired in proportion to LV function. Systolic torsion in LV dysfunction was characterized by the discontinuing counter-rotation of the apex to the base before end-systole. Presented in part at the Annual Scientific Session of ACC 2004 in New Orleans, USA There are no financial obligations that could lead to conflict of interest regarding this study.     

扩张型心肌病发病机理及治疗进展

扩张型心肌病(DCM)以左心室或双心室扩张及收缩功能受损为特征,其发病机理主要与病毒感染后的自身免疫反应有关。80年代以后,遗传因素与DCM的关系逐渐受到重视。DCM的基本治疗是纠正心力衰竭,心律失常及预防血栓栓塞等并发症。针对免疫介导的心肌损伤的早期干预已成为DCM的主要治疗方法。在DCM早期应用地尔硫和β-受体阻滞剂治疗,可以阻止免疫介导的心肌损害,改善患者预后。     

Prognostic value of posterior wall thickness in childhood dilated cardiomyopathy and myocarditis

M-mode indices of left ventricular dimension and posterior wallthickness were derived from echocardiograms of children presentingwith dilated cardiomyopathy/myocarditis and were related tooutcome. Echocardiograms from 16 of 18 children were manuallydigitized to obtain changes of left ventricular dimension andposterior wall thickness throughout the cardiac cycle. Indicesof ventricular function and the ratio of end-diastolic posteriorwall thickness to cavity dimensions were obtained. Patients were divided into group I (alive, n=7), and group II(died, n=6 or heart transplantation, n=3) at median follow-upof 25 months. No significant difference was seen for the shorteningfraction, the percentage of posterior wall thickening or thenormalized peak rate of left ventricular filling. The normalizedpeak rate of posterior wall thinning was greater in group II.The posterior wall thickness to cavity dimension ratio was higherin group I (median=0·19) than group II (median=0·13)(P<0·005). Five of six survivors, whose ventricularfunction improved, had ratios >0·17. All but one witha ratio 0·16 remained with a dilated heart, died or requiredtransplantation (P=<0·01). A relatively thicker posterior wall (ratio >0·17)was associated with better prognosis and recovery. This indexshould be taken into account in decision-making regarding timingfor cardiac transplantation.     

Sympathetic deactivation by growth hormone treatment in patients with dilated cardiomyopathy

Aims We examined the effects of growth hormone administration onthe sympathetic nervous system in patients with idiopathic dilatedcardiomyopathy. Background Growth factor therapy is emerging as a new potential optionin the treatment of heart failure. Although growth hormone providesfunctional benefit in the short term, it is unknown whetherit affects the sympathetic nervous system, which plays a rolein the progression of heart failure. Methods Seven patients with idiopathic cardiomyopathy received 3 monthstreatment with recombinant human growth hormone (0·15–0·20IU.kg^–1.week^–1). Standard medical therapy was unchanged.Myocardial norepinephrine release, both at rest and during submaximalphysical exercise, plasma aldosterone, and plasma volume weremeasured before and after growth hormone treatment. Myocardialnorepinephrine release was assessed from arterial and coronaryvenous plasma concentrations of unlabelled and tritiated norepinephrineand coronary plasma flow (thermodilution). Results Growth hormone induced a significant fall in myocardial norepinephrinerelease in response to physical exercise (from 180±64to 99±34ng.min^–1; P<0·05). Basally, plasmaaldosterone was 189±28 and 311±48pg.ml^–1inthe supine and upright position, respectively, and fell to 106±16(P<0·01) and 182±29pg.ml^–1(P<0·05)after growth hormone therapy. Growth hormone increased plasmavolume from 3115±493ml to 3876±336ml (P<0·05),whereas serum sodium and potassium concentrations were unaffected. Conclusions The data demonstrate that growth hormone administration to patientswith idiopathic cardiomyopathy reduces myocardial sympatheticdrive and circulating aldosterone levels. This neurohormonaldeactivation may be relevant to the potential, long-term useof growth hormone in the treatment of patients with heart failure.     

Left ventricular structure and diastolic function by cardiac magnetic resonance imaging in hypertrophic cardiomyopathy

ObjectiveDiastolic dysfunction is common in hypertrophic cardiomyopathy (HCM) and hypertensive heart disease (HHD), but its relationships with left ventricular (LV) parameters have not been well studied. Our objective was to assess the relationship of various measures of diastolic function, and maximum left ventricular wall thickness (MLVWT) and left ventricular mass index (LVMI) in HCM, HHD and normal controls using cardiac magnetic resonance imaging (CMR). We also assessed LV parameters and diastolic function in relation to late gadolinium enhancement (LGE) and right ventricular (RV) hypertrophy in HCM.Methods41 patients with HCM, 21 patients with HHD and 20 controls were studied. Peak filling rate (PFR), time to peak filling (TPF), MLVWT and LVMI were measured using CMR. LGE and RV morphology were assessed in HCM patients.ResultsMLVWT correlated with TPF in HCM (r = 0.38; p = 0.02), HHD (r = 0.58; p = 0.01) and controls (r = 0.54; p = 0.01); correlation between MLVWT and TPF was weaker in HCM than HHD. LVMI did not correlate with diastolic function. In HCM, LGE extent correlated with MLVWT (τ = 0.41; p = 0.002) and with TPF (τ = 0.29; p = 0.02). The HCM patients with RV hypertrophy had higher MLVWT (p < 0.001) and TPF (p = 0.03) than patients without RV hypertrophy.ConclusionMLVWT correlates with diastolic function (TPF) in HCM, HHD and controls. LVMI did not show significant correlation with TPF. The diastolic dysfunction in HCM is not entirely explained by wall thickening. LGE and RV involvement are associated with worse LV diastolic function, suggesting that these may be markers of more severe underlying myocardial disarray and fibrosis that contribute to diastolic dysfunction.     

肌钙蛋白和C-反应蛋白在缺血性心肌病与扩张型心肌病中的变化

目的探讨肌钙蛋白（cTn-I）和超敏G反应蛋白（hs-CRP）在缺血性心肌病与扩张型心肌病患者中的变化。方法101例心肌病患者行冠脉造影检查，分为缺血性心肌病组（ICM组，53例）和扩张型心肌病组（DCM组，48例）。测定患者在不同NYHA分级时血清cTn-I和hs-CRP浓度。结果ICM患者平均血清hs-CRP浓度高于DCM患者，分别为（4．13±1107）和（2．64±1．19）mg／L；在相同NYHA时，ICM患者的血清hs-CRP浓度明显高于DCM患者（P〈0．01）。ICM患者血清平均cTn-I浓度与DCM患者相似，分别为（0．31±0．27）和（0．34±0．33）μg／L；ICM和DCM患者血清cTn-I浓度在相同NYHA时比较无显著性差异（P〉0．05）。无论是ICM患者还是DCM患者，血清hs-CRP和cTn-I浓度均随心衰程度加重而增高，NYHA Ⅲ和Ⅳ级患者血清hs-CRP和cTn-I浓度明显高于NYHA Ⅰ和Ⅱ级患者（P〈0．01）。结论ICM患者和DCM患者血清hs-CRP和cTn-I浓度随心衰程度加重而增高。ICM患者血清hs-CRP浓度明显高于DCM患者，而两组cTn-I浓度比较无显著性差异。心衰患者cTn-I升高非冠状动脉缺血所致，而与心衰本身有关。     

螺内酯对扩张型心肌病大鼠心肌重塑的影响

目的观察螺内酯对扩张型心肌病（DCM）大鼠心肌重塑的影响。方法取正常大鼠10只作为对照组,DCM大鼠模型40只,随机分为4组：DCM对照组、螺内酯干预低剂量组、中剂量组、高剂量组,灌胃量分别为生理盐水10ml／（kg·d）,螺内酯10、20、40mg／（kg·d）,并于给药8周后处死取心肌观察胶原含量,测定胶原容积百分比,取血清检测BI型前胶原氨端肽（PmNP）。多组均数比较用q检验及方差分析。结果心肌胶原容积百分比比较：螺内酯干预中剂量组（12．13±0．45）％、高剂量组（11．30±1．10）％与DCM对照组（24．33±0．92）％比较减少（P〈0．05）。血清PIHNP水平比较：螺内酯干预中剂量组[（131．95±9．20）ng／ml]、高剂量组[（226．08±22．10）ng／m1]与DCM对照组[（234．17±26．60）ng／ml]比较下降（P〈0．05）。结论予以DCM大鼠螺内酯20ml/（kg·d）或40mg／（kg·d）治疗8周可改善胶原沉积,一定程度上逆转心肌重塑。     

Prospective validation of a quantitative method for differentiating ischemic versus nonischemic cardiomyopathy by technetium-99m sestamibi myocardial perfusion single-photon emission computed tomography

BACKGROUND: Myocardial perfusion single-photon emission computed tomography (SPECT) permits assessment of stress perfusion and resting left ventricular (LV) function. Quantitative analysis of perfusion patterns among patients with LV dysfunction offers an opportunity for developing criteria to differentiate ischemic from nonischemic cardiomyopathy. HYPOTHESIS: Quantitative assessment of SPECT may allow differentiation between ischemic and nonischemic cardiomyopathy. METHODS: We evaluated 144 patients with LV ejection fraction < or =40%, divided into 63 patients with nonischemic and 81 with ischemic cardiomyopathy. Mean relative myocardial counts were obtained for regions drawn over defect and normal zones on rest and stress polar perfusion maps. RESULTS: Multivariate logistic regression analysis of significant univariate SPECT predictors of ischemic cardiomyopathy revealed that the stress defect severity ratio (SDSR) was the best predictor of ischemic cardiomyopathy (p < 0.0001). By receiver operator characteristic (ROC) curve analysis, an SDSR of < or =45% optimized prediction of ischemic cardiomyopathy (sensitivity 81%, specificity 96%). An SDSR of < or =45% occurred in 65 of 81 (80%) patients with ischemic cardiomyopathy, but in only 3 of the 63 (4%) patients with nonischemic cardiomyopathy (p < 0.0001). Applying the < or =45% SDSR threshold to a prospective group of 89 patients yielded a somewhat lower sensitivity (60%), but retained high specificity (91%) for identifying ischemic cardiomyopathy (p = NS vs. retrospective group). CONCLUSIONS: Presence of a severe and extensive stress perfusion defect is a hallmark of ischemic cardiomyopathy. By contrast, a mild stress perfusion defect (SDSR of >45%) is commonly present among patients with ischemic and nonischemic cardiomyopathy. An SDSR of < or =45% is a reproducible specific marker for identifying the presence of ischemic cardiomyopathy.     

Cardiovascular reserve in idiopathic dilated cardiomyopathy as determined by exercise response during cardiac catheterization

Simultaneous right- and left-sided cardiac high-fidelity hemodynamic measurements were obtained at rest and supine exercise during cardiac catheterization in 27 patients (mean age 32 +/- 10 years) with idiopathic dilated cardiomyopathy to investigate the hemodynamic exercise response and possible mechanisms for the wide variation in exercise tolerance observed clinically. There were no significant differences in other rest hemodynamic variables between group 1, patients with a normal exercise factor (more than 600, n = 10), and group 2, patients with an abnormal exercise factor (less than 600, n = 17). A greater increase in stoke volume index (12 +/- 6 vs 2 +/- 8 ml/beats/m2, mean +/- standard deviation) and a greater decrease in systemic vascular resistance with exercise occurred in group 1 than in group 2 (-614 +/- 304 vs -406 +/- 291 dynes cm-5). Elevation of right ventricular end-diastolic pressure with exercise was significantly greater in group 2 than in group 1 (7 +/- 5 vs 1 +/- 4 mm Hg, respectively, p less than 0.05). A maintained cardiac reserve in patients with idiopathic dilated cardiomyopathy appears to be largely dependent on 2 primary factors: preservation of normal right ventricular function during exercise; and preservation of systemic vasodilator capability sufficient to produce a significant degree of afterload reduction during exercise.     

Use of cardiac magnetic resonance imaging for alcohol septal ablation in hypertrophic obstructive cardiomyopathy

Abstract

This is a report of a 58-year-old man with severe hypertrophic obstructive cardiomyopathy who underwent alcohol septal ablation to relieve symptoms due to severe left ventricular outflow obstruction. Cardiac magnetic resonance was performed before and after the procedure. This case highlights the potential use of cardiac magnetic resonance imaging in the surgical planning of alcohol septal ablation as well as following the procedure to assess for complications and morphological changes.     

Prognostic value of pulsed tissue Doppler imaging for the assessment of left ventricular systolic function in patients with nonischemic dilated cardiomyopathy

There is still some debate regarding the prognostic significance of left ventricular longitudinal systolic dysfunction as assessed by tissue Doppler (TD) imaging in patients with chronic heart failure (HF), since previous studies have included patients with postischemic wall motion abnormalities. Thus, this study was designed to ascertain whether TD-derived longitudinal systolic dysfunction may influence the outcome of patients with nonischemic chronic HF. In 200 consecutive patients with chronic HF secondary to dilated cardiomyopathy and no history of ischemic heart disease, peak systolic mitral annular velocity (S(m) ) was measured by pulsed TD at the septal and lateral annular sites. The end points were cardiac death or hospitalization for worsening HF. Mean follow-up duration was 30 months. In a time independent analysis, averaged S(m) calculated as the average of septal and lateral S(m) , resulted to be a significant predictor of outcome in the study population (area under receiver-operator characteristic curve: cardiovascular death, 0.69, P < 0.0001; cardiovascular events, 0.64, P = 0.0005). In a time-dependent analysis, average S(m) was associated with both cardiovascular death (hazard ratio 0.832, P = 0.0019) and cardiovascular events (hazard ratio 0.904, P = 0.039), independently of other clinical risk factors and echocardiographic parameters of systolic function. Septal S(m) but not lateral S(m) was independently associated with the outcome measures. In conclusion, the assessment of systolic mitral annular velocity by pulsed TD is a useful indicator for prognostic stratification of patients with nonischemic dilated cardiomyopathy and chronic HF.     

扩张型心肌病患者磁共振下心肌特征与室性心律失常的关系

目的:探究非缺血性扩张型心肌病(NIDCM)患者磁共振下心肌强化特征与发生室性心律失常(VA)事件的关系,找出相关危险因素.方法:将2019年11月-2021年7月于郑州大学第一附属医院就诊的154例NIDCM患者纳入研究.根据发生VA事件的情况将其分为对照组及失常组,比较两组患者的一般资料及心脏磁共振延迟强化(LGE...