超声心动图在肥厚型心肌病诊断与评估中的应用进展

肥厚型心肌病是以心肌肥厚为特征的原发性心肌病。典型的病理表现为室间隔和左心室游离壁非对称性肥厚,常导致劳力性左心室流出道梗阻。患者的表现为呼吸困难、胸痛、心悸、头晕、黑朦甚至昏厥,为青壮年猝死的主要原因之一。超声心动图作为早期诊断肥厚型心肌病首选的无创方法近年取得较大进展。该文介绍超声心动图在评估心肌肥厚程度、二尖瓣功能、左室流出道梗阻程度以及心脏收缩、舒张功能方面的进展。     

肥厚型心肌病患者危险性室性心律失常分析

目的　探讨肥厚型心肌病左心室肥厚的程度与室性心律失常发生的关系。方法　对 60例患者分别作多普勒、二维超声及2 4h动态心电图检测 ,对照分析危险与非危险性室性心律失常的左心室肥厚的程度、左心室流出道梗阻、舒张功能情况。结果　危险性与非危险性室性心律失常的患者分别为 2 3例 ( 38.3% )与 37例 ( 61.7% ) ,两组间左心室壁厚度、左心室舒张功能存在显著差异 ,前者异常程度严重 ;梗阻型较非梗阻型患者的危险性室性心律失常明显增加。结论　肥厚型心肌病危险性心律失常的发生率与左心室肥厚的程度及流出道梗阻有关     

肥厚型心肌病患者临床特征及肥厚节段分析

目的 对肥厚型心肌病患者临床特征及其受累肥厚节段的分布和程度进行分析.方法 连续收集2004年3月至2007年3月225例临床诊断或可疑的肥厚型心脏病患者的临床资料,包括症状、体征、心电图检查及超声心动图检查等.所有患者均接受心脏核磁共振检查.依据9节段分析法分析受累节段范围、程度等.结果 肥厚型心肌病患者中男163例,女62例,平均年龄(50.4±14.5)岁.28例肥厚型心肌病患者临床无症状,系通过体检发现.197例肥厚型心肌病患者临床症状明显,其中11例伴发晕厥.216例肥厚型心肌病患者心电图异常,73例患者有明确家族史.126例肥厚型心肌病患者可闻及收缩期杂音.超声心动图发现95例患者合并左心室流出道梗阻,32例患者伴发二尖瓣关闭不全.肥厚型心肌病患者合并高血压50例,合并冠心病14例,合并糖尿病5例.225例患者左心房前后径平均为(39.4±8.3)mm,左心室舒张末期横径平均为(47.8±5.5)mm.依据9节段分析法,32.1%的节段受累.非对称性肥厚患者222例,其中室间隔受累198例,对称性肥厚患者3例.心尖受累67例,其中单独心尖受累24例.98例患者室间隔和左心室前壁同时受累.所有室间隔肥厚患者室间隔平均厚度为(23.0±5.2)mm.其中伴发左心室流出道梗阻患者室间隔平均厚度为(24.3±5.3)mm,高于无梗阻患者(21.6±4.6)mm,P＜0.05.所有心尖肥厚患者心尖平均厚度为(15.6±3.4)mm.结论 我国肥厚型心肌病患者男性比例较高,临床发病时间较晚.心脏磁共振能很好地评估肥厚型心肌病各个亚型的病理解剖学特征,是准确诊断肥厚型心肌病的有效方法.     

肥厚型心肌病的临床分型与分析

目的 对肥厚型心肌病的临床，心电图、超声心动图等资料进行分析。提高对复杂病例的诊断与鉴别诊断水平。方法 利用超声心动图，结合磁共振等特殊检查。对48例病人进行分型和分析。结果 按血流动力学特征，可分为梗阻型10例（均为左心室），非梗阻型38例；按肥厚部位则可分为右心室肥厚型1例，双室肥厚型2例，左心室肥厚型45例，其中乳头肌肥厚1例，肥厚扩张型3例。心尖肥厚14例，室间隔或/和侧壁肥厚27例。结论 肥厚型心肌病可因其血流动力学或病理解剖学特征的不同而表现迥异；正确诊断有赖于对病史，临床表现，心电图，超声心动图及其他特殊检查资料的综合分析和判断。     

肥厚型心肌病左室舒张功能及影响因素的研究

目的评价肥厚型心肌病左室舒张功能受损程度及其可能影响因素.方法使用经胸多普勒超声心动图检测56例肥厚型心肌病患者二尖瓣及肺静脉口血流频谱来评价其舒张功能,探讨左室肥厚程度、左室流出道梗阻等因素对舒张功能损害程度有无影响.结果95%肥厚型心肌病患者存在左室舒张功能受损,其中轻、中、重度损害分别占59%、27%、9%,舒张功能损害程度同左室肥厚程度等因素均无关.结论绝大多数肥厚型心肌病患者存在不同程度的左室舒张功能受损,经胸超声联合检测二尖瓣及肺静脉口血流频谱可准确有效地评价舒张功能,肥厚型心肌病左室舒张功能受损同心肌肥厚程度等因素无关.     

心尖肥厚型心肌病

肥厚型心肌病按是否伴有左心室流出道动力性梗阻和压力阶差,分为梗阻性和非梗阻性两大类。梗阻性的特点是室间隔非对称性肥厚,而非梗阻性则表现为非对称性左心室前壁、侧壁、后壁、心尖和左心室中部(mid-zone)肥厚及左心室向心性肥厚。1976年,日本学者 Yamaguchi 等和 Sa-kamoto 等首先报告,心电图有深尖倒置 T波(Giant NegatiVe T,GNT)和左心室高电压的患者,超声心动图可见左心室心尖部向心性肥厚,右前斜位左心室造影舒张末期“黑     

心尖肥厚型心肌病

心尖肥厚型心肌病属于原发性肥厚型心肌病中的特殊类型,首先由日本学者Yamaguchi等于1976年报告。它与经典的肥厚型心肌病不同,常不伴有左心室流出道动力性梗阻和压力阶差。肥厚的心肌主要位于前侧壁心尖处,而室间隔基底部却多无肥厚。近年来由于超声心动图尤其是二维超声心动图的广泛应     

肥厚性心肌病的心室造影特点

目的分析梗阻型肥厚性心肌病(HOCM)患者心室造影结果及形态学特征。方法纳入1995~2005年收治入院并接受心室造影和超声检查的74例确诊为肥厚型心肌病的患者。以左心室流出道与左心室压力差≥30 mmHg为梗阻型,30 mmHg为非梗阻型,将患者分为2组。比较其形态学和造影结果。结果 (1)入选74例患者,梗阻型14例(18.9%),其中收缩期前向运动6例(42.9%),冠心病3例(21.4%);非梗阻型60例(81.1%),其中11例合并冠心病(18.3%)。(2)超声显示室间隔增厚至(11.4±2.5)mm,左室后壁厚度(9.8±1.7)mm,左心室舒张末内径(48±5)mm,左心房内径(36±5)mm。(3)左室造影显示左室舒张末容积为(123±31)ml,左室收缩末容积为(27±11)ml,左心室射血分数(EF)为(78±6)%。(4)左心室造影形态学特征为梗阻型心室结构14例,其中正常5例;非梗阻型左心室结构60例,正常27例。结论非梗阻型肥厚性心肌病与HOCM左室舒张末内径、左室舒张末容积及左室收缩末容积、EF值,以及呈现正常形态的病例数等均无差异。     

心尖肥厚型心肌病临床诊断探讨(附18例临床报告)

以心电图、超声心动图、放射核素心肌断层显像（99mTC－MIBI）、冠状动脉造影及左心室造影等检查方法，诊断18例心尖肥厚型心肌病。18例心电图显示胸导联倒置的T波呈TV4＞TV5TV5＞DV6的关系。超声心动图左心室心尖部（乳头肌水平以下）心肌肥厚，达12mm以上。8例行放射核素心肌断层显像见左心室心尖部心肌肥厚。10例左心室造影均提示心尖部心肌肥厚，其中6例左心室舒张末期呈"黑桃"样改变，冠状动脉造影正常。此文就18例心尖肥厚型心肌病的临床诊断进行探讨。     

少见类型肥厚型心肌病的超声心动图诊断与鉴别诊断

分析少见类型肥厚型心肌病患者的超声心动图特点 ,提高超声心动图对该病诊断的准确性。利用Acuson12 8XP10彩色电脑声像仪分析了 38例经临床及超声心动图诊断为肥厚型心肌病患者的有关资料 ,采取二维超声心动图多切面、多角度观测室间隔、游离壁厚度和活动幅度以及二尖瓣活动特点 ;M型超声心动图Ⅱa区、Ⅳ区测量房室腔内径及室壁厚度 ;多普勒超声心动图记录左室流出道血流速度、二尖瓣频谱形态及二尖瓣返流速度。 38例肥厚型心肌病患者中 ,以Ⅲ型最为多见 ,占 4 5%。少见类型中心尖肥厚型 2例 ,心尖最厚达 33mm ;后下壁及下间隔肥厚型各 1例 ;对称型肥厚者 2例 ;高血压合并肥厚型心肌病者 2例。肥厚型心肌病的肥厚心肌分布比较复杂 ,少见类型肥厚型心肌病的诊断更应注意多切面、多角度进行探查 ,避免漏诊及误诊。     

Four cases of Fabry's disease mimicking hypertrophic cardiomyopathy

Four patients with Fabry's disease diagnosed by right ventricular endomyocardial biopsy had cardiac manifestations simulating hypertrophic cardiomyopathy (HCM). Case 1: A 51-year-old woman, whose elder sister had congestive heart failure, was hospitalized for exertional dyspnea and cardiomegaly. Her electrocardiogram (ECG) showed a short PQ interval (0.10 sec) and left ventricular hypertrophy. Her echocardiogram (Echo) showed moderate symmetrical hypertrophy of the left ventricle (IVST/PWT = 18 mm/17 mm). Case 2: A 32-year-old woman, whose elder sister had an abnormal ECG, was hospitalized for the ECG abnormalities consisting of a short PQ interval (0.10 sec) and ST-T changes in the left precordial leads. The Echo revealed mild symmetrical hypertrophy of the left ventricle (IVST = 13 mm, PWT = 13 mm). Case 3: A 44-year-old man was hospitalized for his ECG suggestive of left ventricular hypertrophy, and his Echo showed asymmetrical septal hypertrophy (ASH; IVST = 22 mm). Case 4: A 51-year-old man was hospitalized for his ECG showing high voltage in the left precordial leads, and his Echo showed ASH (IVST = 20 mm). The cardiac histopathological findings of these cases included cytoplasmic vacuolization by light microscopy, and electron-dense deposits consisting of parallel or concentric lamellae with periodic spacing, suggesting Fabry's disease. The urinary glycolipids of Case 1 were increased biochemically; then the diagnosis of Fabry's disease was confirmed. Cardiac hypertrophy in Fabry's disease has many aspects, because the histopathological changes and clinical manifestations are determined by genetic factors. It was concluded that Fabry's disease may be concealed in some patients with the clinical diagnosis of HCM.     

Structural abnormalities of the inferoseptal left ventricular wall detected by cardiac magnetic resonance imaging in carriers of hypertrophic cardiomyopathy mutations.

OBJECTIVES: The purpose of this study was to evaluate whether structural left ventricular (LV) abnormalities can be observed in hypertrophic cardiomyopathy (HCM) mutation carriers who have not yet developed echocardiographic signs of hypertrophy by using cardiac magnetic resonance imaging (CMR). BACKGROUND: Hypertrophic cardiomyopathy is caused by mutations of genes encoding for sarcomeric proteins. Myocyte disarray and interstitial fibrosis precede the development of regional hypertrophy in HCM mutation carriers (carriers). No macroscopic LV structural abnormalities have been observed in carriers without LV hypertrophy. METHODS: A CMR, echocardiogram, and electrocardiogram (ECG) were performed in 16 carriers. Delayed contrast enhancement imaging was used with CMR to detect fibrosis. In 16 age- and gender-matched control subjects, CMR and ECG were performed and an echocardiogram was made when structural abnormalities were detected with CMR. All carriers had an LV wall thickness <13 mm in the year before the study, measured by echocardiography. RESULTS: In 13 carriers (81%), crypts were discerned with CMR in the basal and mid inferoseptal LV wall, not detected by routine echocardiography and not observed in healthy volunteers. In 4 of the crypt-positive carriers, both the echocardiogram and ECG were normal. Two HCM carriers revealed regional hypertrophy of the inferoseptum not detected by echocardiography, and in both carriers, focal fibrosis was present. CONCLUSIONS: In carriers who have not yet developed frank hypertrophy, crypts can be detected with CMR in the inferoseptal LV wall, even when echocardiography and ECG are normal. The crypts might represent one of the early pathological alterations of myocardium in carriers that ultimately progress into manifest HCM.     

高血压所致左心室肥厚与肥厚型心肌病体表心电图和超声心动图的鉴别要点

目的 比较高血压所致左心室肥厚与肥厚型心肌病（HCM）患者体表心电图及超声心动图参数之间的差异，探讨体表心电图对二者鉴别诊断的临床应用价值。 方法 收集高血压致左心肥厚（H-LVH）患者，HCM患者及正常对照各49例。常规测量心电图中的P波时限、QTC时限，QRS波时限、异常q波数量、R波及S波振幅和ST-T与QRS波方向一致率，超声心动图中测量E/A、左室射血分数（LVEF）、室间隔厚度、左房内径（LA）、左心室收缩末期左右径（LVs左右径）、左心室舒张末期左右径（LVd左右径）、左心室收缩末期前后径（LVs前后径）、左心室舒张末期前后径（LVd前后径）、左心室收缩末期长轴（LVs长轴）、左心室舒张末期长轴（LVd长轴）等参数，比较3组之间的差异。 结果 HCM组患者与H-LVH组患者比较，最大左心室室壁厚度显著增厚，LVEF显著升高（均P<0.05），而HCM每博排出量（SV）、LVs左右径、LVd左右径、LVs前后径、LVd前后径、LVd长径显著小于H-LVH（均P<0.05）；心电图提示，HCM组患者II，III，Avf V1 V2导联R波与S波电压之和，QTC时限显著高于H-LVH组患者（P<0.01）；HCM患者异常Q波数量以及III、aVR导联ST-T与QRS波方向一致率显著高于H-LVH组（P<0.01）。 结论 超声心动图可从左心室最大室壁厚度及肥厚特征鉴别HCM患者和H-LVH患者；体表心电图鉴别二者需结合QRS波振幅之和，QTC时限，II、V4导联异常Q波数量及导联ST-T与QRS波方向在V2、V3、V6导联的一致率4个参数。     

Functional assessment by myocardial performance index (Tei index) correlates with plasma brain natriuretic peptide concentration in patients with hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) might exhibit not only diastolic, but also latent systolic dysfunction. Therefore combined assessment of both systolic and diastolic function using myocardial performance index (Tei index) can be useful in HCM. Plasma brain natriuretic peptide (BNP) level is reported to be elevated in HCM, but the mechanism of BNP elevation in HCM remains to be established. METHODS AND RESULTS: The value of Tei index in 45 HCM patients was compared with that of 20 normal control subjects. The HCM patients showed a higher value of Tei index (0.55+/-0.12 vs 0.36+/-0.08, p < 0.0001) and longer isovolumic relaxation and contraction times than control subjects. The plasma BNP level correlated with Tei index in non-obstructive HCM (n = 35, r = 0.61, p < 0.0001), although the correlation was mild when overall HCM patients were included (r = 0.34, p = 0.02). The correlation was still significant after adjusting for age, or the extent and severity of left ventricular hypertrophy. Multiple stepwise regression analysis identified mitral E/A ratio (r = 0.49, F = 13.1) and Tei index (r = 0.37, F = 7.6) as independent predictors of higher plasma BNP level in non-obstructive HCM. CONCLUSIONS: Myocardial performance index was abnormal in HCM, reflecting both systolic and diastolic dysfunction in this disorder. Plasma BNP level correlated with functional assessment by Tei index in non-obstructive HCM.     

Effect of regional myocardial perfusion abnormalities on regional myocardial early diastolic function in patients with hypertrophic cardiomyopathy

Summary Nonuniform hypertrophy of the left ventricle is an important factor in regional diastolic dysfunction in patients with hypertrophic cardiomyopathy (HCM). However, the effect of myocardial perfusion abnormalities on regional diastolic dysfunction has not been established in patients with HCM. We investigated the relationship between regional myocardial perfusion abnormalities and regional early diastolic function in 31 patients with HCM and 8 control patients. Short-axis images of the left ventricle recorded by cine magnetic resonance imaging were divided into ten blocks. The time-to-peak-wall-thickness-thinning rate (TPWR) and the wall thickness were measured in each block. Of the 310 blocks from the patients with HCM, 242 (78%) showed normal thallium-201 uptake (group 1), 40 (13%) showed slightly decreased uptake (group 2), and 28 (9%) showed markedly decreased uptake (group 3). There was no difference in the regional wall thickness among the three groups. The TPWR was longer in patients with HCM than in control patients. It was significantly longer in group 3 (190±45ms) than in group 1 (167±36ms) and group 2 (160±31ms). (P<0.01). The linear regression slope of the relationship between the TPWR and the regional wall thickness was significantly steeper in group 3 than in groups 1 and 2 (P<0.05). In conclusion, abnormalities in regional myocardial perfusion, in addition to regional hypertrophy, contributed to the regional early diastolic dysfunction in patients with HCM.     

Assessment of Left Atrial Function in Hypertrophic Cardiomyopathy and Athlete's Heart: A Left Atrial Myocardial Deformation Study

Background: Hypertrophic cardiomyopathy (HCM) is a common cause of sudden death in athletes and differentiating this condition from the nonpathological "athlete's heart" remains a challenge. The development of pathological left ventricular hypertrophy (LVH) is associated with left atrial (LA) dilatation and dysfunction. LA strain and strain rate by two-dimensional (2D) speckle tracking are novel indices of LA function and might contribute to differentiate physiological from pathological LVH among athletes with underdiagnosed HCM. Methods: We evaluated 20 patients with nonobstructive HCM, 20 highly trained athletes and 20 healthy controls matched for age, gender, and body surface area. All patients underwent a transthoracic echocardiogram with evaluation of LA strain: s-wave (LASs); and strain rate: s-wave (LASRs) and a-wave (LASRa). Results: LV mass index, LA volume index, and ejection fraction were comparable between patients with HCM and athletes. Patients with HCM had a significantly lower LASs (19 + 8% vs. 43 + 8%, P < 0.01), LASRs (0.7 + 0.2 s-1 vs. 1.6 + 0.2 s-1, P < 0.01), and LASRa (-0.8 + 0.1 s-1 vs. -1.4 + 0.3 s-1, P < 0.01) compared to athletes. Among hypertrophic subjects, independent predictors of hypertrophy related to HCM were LASs and E/é ratio. Conclusions: LA myocardial deformation is significantly impaired in patients with HCM compared to athletes and healthy controls. LA strain and strain rate assessed by 2D speckle tracking should be incorporated in the evaluation of trained athletes with LVH and LA dilatation.     

Correlation of Electrocardiographic Changes and Myocardial Fibrosis in Patients With Hypertrophic Cardiomyopathy Detected by Cardiac Magnetic Resonance Imaging

Background:

Despite several electrophysiologic and pathologic studies, the cause of electrocardiographic (ECG) changes in patients with hypertrophic cardiomyopathy (HCM) remains unclear. Late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging can detect myocardial fibrosis. We aimed to assess the relationship between ECG findings and LGE in such patients.

Hypothesis:

Myocardial LGE may be associated with ECG changes in HCM.

Methods:

Seventy consecutive patients with HCM (mean age, 55.5 ± 10.7 years; 47 males) underwent CMR and 12‐lead ECG. The subjects were divided into 3 groups according to the type of hypertrophy: the asymmetric septal hypertrophy group (ASH group, n = 31), the apical hypertrophy group (AP group, n = 22), and concentric hypertrophy group (CH group, n = 17). The transmural and segmental extent, pattern, and location of myocardial LGE were assessed and analyzed in relation to ECG changes.

Results:

All of the subjects showed some degree of LGE on CMR. The AP group showed significantly higher prevalence of negative T‐wave (P = 0.028) and deep negative T‐wave inversion (P = 0.001) than the ASH and CH groups. The total volume of LGE did not show any significant association with ECG changes. LGE detected at the interventricular septum was associated with increased QRS duration (P = 0.009) and was found in 94% of the ASH group, 59% of the AP group, and 77% of the CH group. LGE at the apex of the heart was present in 32% of the ASH group, 73% of the AP group, and 35% of the CH group and was also associated with negative T‐wave (P = 0.006) and deep negative T‐wave inversion (P = 0.018). Multifocal LGE lesions were associated with increased QRS duration (P = 0.039) as opposed to single nodular or patchy pattern of presence.

Conclusions:

The location of myocardial LGE in HCM shows significant association with various ECG changes. This may be useful information for initially evaluating subjects with HCM and adds pathophysiological insight into understanding ECG changes in myocardial diseases that cannot be explained otherwise. Clin. Cardiol. 2011 DOI: 10.1002/clc.22062 The authors have no funding, financial relationships, or conflicts of interest to disclose.     

Simple criteria for differentiation of Fabry disease from amyloid heart disease and other causes of left ventricular hypertrophy

AIMS: Fabry disease may be difficult to differentiate from other causes of left ventricular hypertrophy such as other myocardial storage diseases (including amyloidosis), hypertrophic cardiomyopathy (HCM), or hypertensive heart disease (HHD). We sought to determine simple criteria to best differentiate the above mentioned cardiac diseases. METHODS AND RESULTS: All patients in a six-year time period with left ventricular hypertrophy due to Fabry disease (13 patients), biopsy proven cardiac amyloidosis (16 patients), non-obstructive HCM (17 patients), and 22 randomly selected patients with advanced HHD were compared. Retrospective analysis of clinical characteristics, findings of electrocardiogram (ECG) and echocardiography by blind review was performed. RESULTS: No single clinical characteristic or findings of ECG or echocardiography could reliably differentiate between the various diseases. Increased echogenicity/granular sparkling, valvular abnormalities, abnormal renal function, and diastolic function were not helpful discriminators. In a univariate analysis, four criteria (acroparesthesia, anhydrosis, absence of hypertension and presence of Sokolow criteria for left ventricular hypertrophy in the ECG) were significant for Fabry disease. By logistic regression analysis, the following most suitable discriminative parameters were identified: hypertension in HHD (specificity 82%), orthostasis and/or pericardial effusion for amyloidosis (specificity 93%), papillary muscle anomaly in non-obstructive HCM (specificity 92%), and Fabry disease if neither hypertension orthostatis, pericardial effusion nor a papillary muscle anomaly was present (specificity 87%). CONCLUSION: A combination of symptoms, echocardiographic findings and ECG in unexplained left ventricular hypertrophy may help to differentiate amyloidosis, non-obstructive HCM and hypertensive heart disease from Fabry disease. The results of this preliminary study will have to be confirmed in a prospective study.     

Biventricular impairment of diastolic function in acromegaly

AIM: Left ventricle impairment is very common in acromegaly. Concentric hypertrophy and diastolic dysfunction are observed at an early stage. Late left ventricle dilatation with systolic dysfunction may appear. Few reports have studied right ventricle diastolic function. METHODS: Twenty-seven acromegalic patients were included. Biventricular diastolic function was assessed using Doppler-echocardiography. Possible associations with hormonal activity, evolution time of illness, hypertension, left ventricular hypertrophy and systolic impairment on echocardiography were studied. RESULTS: Fifteen patients showed left ventricular diastolic dysfunction, whereas thirteen patients showed right ventricular diastolic dysfunction. A good correlation was observed between E/A relation of both ventricles (r = 0.70; p < 0.01) and isovolumetric relaxation time (r = -0.60; p < 0.01). The right ventricular E/A relation correlated with left ventricular mass index and significance was almost achieved with the presence of hypertension. There was no statistical correlations between the right ventricular E/A relation and hormone values or evolution time of illness. The left ventricular E/A relation showed a significant association with left ventricular mass index, isovolumetric time index and evolution time of illness. There were no statistical association with hormone values. CONCLUSIONS: The high prevalence of right ventricular diastolic dysfunction observed in acromegaly suggests the presence of acromegalic myocardiopathy.