心尖肥厚型心肌病的研究进展

心尖肥厚型心肌病(AHCM)是肥厚型心肌病(HCM)的一种较为罕见的表型,其肥厚部位主要限于左室心尖部,主要以V4~V6巨大倒置T波及左室造影呈“锹状”改变为特征。本文对该病发病情况、病因、病理、病理生理及诊治情况的最新进展作一综述。     

Noninvasive and invasive study procedures in hypertrophic cardiomyopathy

Noninvasive and invasive diagnostic procedures permit a differentiated insight into the hypertrophic cardiomyopathies. For a better understanding of the disease, classification according to morphologic and functional criteria was introduced. It has proven useful to subdivide hypertrophic obstructive cardiomyopathy into two types: idiopathic hypertrophic subaortic stenosis and midventricular obstruction; hypertrophic nonobstructive cardiomyopathies can be subdivided into two forms designated as asymmetrical septal hypertrophy and apical hypertrophy. Combined forms can also be recognized. With a high degree of accuracy, it is possible to differentiate between hypertrophic obstructive and hypertrophic nonobstructive cardiomyopathy by means of noninvasive procedures such as clinical examination, electrocardiography, mechanocardiography and, above all, echocardiography. Experience has shown that two-dimensional echocardiography, in particular, has assumed an especially important role, the value of which approaches that of cardiac catheterization. In this overview, emphasis is placed on the diagnostic peculiarities of idiopathic hypertrophic subaortic stenosis as well as the findings in midventricular obstruction and apical hypertrophy. In the past, only relatively little attention has been focused on the latter subgroups even though they can be diagnosed with a high degree of accuracy with noninvasive as well as invasive procedures.     

Two Cases of Apical Ballooning Syndrome Masking Apical Hypertrophic Cardiomyopathy

Apical akinesis and dilation in the absence of obstructive coronary artery disease is a typical feature of stress-induced (takotsubo) cardiomyopathy, whereas apical hypertrophy is seen in apical-variant hypertrophic cardiomyopathy. We report the cases of 2 patients who presented with takotsubo cardiomyopathy and were subsequently found to have apical-variant hypertrophic cardiomyopathy, after the apical ballooning from the takotsubo cardiomyopathy had resolved. The first patient, a 43-year-old woman with a history of alcohol abuse, presented with shortness of breath, electrocardiographic and echocardiographic features consistent with takotsubo cardiomyopathy, and no significant coronary artery disease. An echocardiogram 2 weeks later revealed a normal left ventricular ejection fraction and newly apparent apical hypertrophy. The 2nd patient, a 70-year-old woman with pancreatitis, presented with chest pain, apical akinesis, and a left ventricular ejection fraction of 0.39, consistent with takotsubo cardiomyopathy. One month later, her left ventricular ejection fraction was normal; however, hypertrophy of the left ventricular apex was newly noted. To our knowledge, these are the first reported cases in which apical-variant hypertrophic cardiomyopathy was masked by apical ballooning from stress-induced cardiomyopathy.     

A case of asymmetrical apical hypertrophy which is a form of hypertrophic nonobstructive cardiomyopathy with giant negative T-waves

Clinical, hemodynamic, electrocardiographic (ECG), echocardiographic, left ventricular (LV), and coronary angiographic (CA) findings are reported in a case with apical hypertrophy (AH), a form of hypertrophic nonobstructive cardiomyopathy (HNCM). The most striking symptom was chest pain and the most conspicuous electrocardiographic finding consisted of giant negative T waves, reaching an amplitude of 4.0 mV. Echocardiography revealed an apical thickness of the septum and posterior wall of 40 mm; this was significantly greater than septal and posterior free wall thickening in the LV outflow area. The anterior motion (SAM) of the anterior mitral leaflet, was present, and, in hemodymic investigation, the isoproterenol test was negative. The left ventricular end-diastolic pressure (LVEDP) and the EF were elevated. In the LV angiogram from the right anterior oblique position (RAO), the LV free wall thickness at the apex was significantly thicker than at the outflow tract level. The patient had dilated coronary arteries. We conclude that these findings are typical for AH (HNCM) and it seems that hypertrophic obstructive cardiomyopathy (IHSS, MO), and hypertrophic non-obstructive cardiomyopathy (ASH, AH) are different manifestations of a wide spectrum of hypertrophic cardiomyopathy.     

The importance of echocardiography for the diagnosis of cardiomyopathies in comparison to cardio-computer tomography and to complex invasive heart diagnostics

112 patients with various forms of cardiomyopathy (typical-subaortic--hypertrophic obstructive; atypical--medioventricular--hypertrophic obstructive; hypertrophic nonobstructive; apical hypertrophic; dilatative) were subjected to echocardiographic examination of the morphological and functional state of the heart. The results were compared with the results of computer heart tomography and comprehensive invasive examination. The high diagnostic reliability of ultrasonic diagnostics has been confirmed. Invasive examination is necessary in hypertrophic nonobstructive and in dilatative cardiomyopathies. Computer heart tomography is suitable for complementing findings and for clarifying contradictory results of examination, especially in apical forms of cardiomyopathy.     

Mid-ventricular hypertrophic obstructive cardiomyopathy presenting with acute myocardial infarction

Mid-ventricular hypertrophic obstructive cardiomyopathy is a rare type of cardiomyopathy that can be accompanied by apical aneurysm. We report the case of a patient who presented with ventricular fibrillation, ST-segment elevation on electrocardiography, and cardiac-enzyme elevation, in the presence of normal coronary arteries. Echocardiography and magnetic resonance imaging showed an hourglass appearance of the left ventricle with an aneurysm in the apex. Left-heart catheterization and continuous-wave Doppler echocardiography revealed a pressure gradient between the apical and basal chambers of the left ventricle. Impaired coronary artery circulation might play a role in the development of mid-ventricular obstruction in patients with mid-ventricular hypertrophic obstructive cardiomyopathy.     

Nonobstructive hypertrophic cardiomyopathy mimicking mitral stenosis. Documentation by echocardiography, phonocardiography and intracardiac pressure and sound recordings.

The physical findings in hypertrophic cardiomyopathy with left ventricular outflow tract obstruction are well described. In the absence of outflow tract obstruction the findings are less distinctive. There have been several reported cases in which the cardiac findings have suggested the diagnosis of mitral stenosis, In this report we describe a patient whose auscultatory and roentgenographic findings more closely mimicked mitral stenosis. The patient had a loud first heart sound, mitral opening snap and an apical presystolic murmur; left atrial enlargement was present. Noninvasive studies, including phonocardiography, echocardiography and apex cardiography, strongly suggested the correct diagnosis of nonobstructive hypertrophic cardiomyopathy. The diagnosis and unusual auscultatory findings were confirmed by results of cardiac catheterization and intracardiac phonocardiography. The importance of recognizing this syndrome and the use of noninvasive methods to establish the diagnosis are stressed.     

Study on the genesis of giant negative T wave in apical hypertrophic cardiomyopathy using a three-dimensional computer model.

Apical hypertrophic cardiomyopathy is characterized by a spade-like left ventricular cavity and by both giant negative T waves and tall R waves in the electrocardiogram. However, the mechanisms of these ECG abnormalities have not been satisfactorily clarified. We have recently developed a three-dimensional computer model of ventricular depolarization and repolarization processes. This model has successfully simulated normal QRST waves and changes characterizing some abnormal conditions. A model of apical hypertrophic cardiomyopathy was constructed by adding model units to the endocardium of the left ventricular apex. The surface ECG was then calculated by assuming different gradients of action potential durations and different proportions of the hypertrophic cells in the apical segment. A negative T wave of -1.45 mV in lead V4, similar to the clinically reported ECG, was obtained by assuming: (1) diffusely distributed hypertrophic cells at the apex and (2) uniform, long action potential durations of hypertrophic cells. It is suggested that these properties may account for the distinctive ECG abnormalities in apical hypertrophic cardiomyopathy.     

Apical Hypertrophic Cardiomyopathy: Preliminary Attempt at Palliation with Use of Subselective Alcohol Ablation

We report a case of severe apical hypertrophic cardiomyopathy in order to discuss the nature of this unusual condition and the possibility of using selective alcohol ablation to effectively treat symptomatic hypertrophic cardiomyopathy that presents with apical aneurysm. A 73-year-old woman with severe, progressive dyspnea and intermittent chest pain was found to have localized left ventricular apical dyskinesia distal to an obstructive mid-distal muscular ring. The ring caused total systolic obliteration of the apical left ventricular cavity. Apical cavity pressure was extremely high, up to 330 mmHg—200 mmHg above that in the main left ventricular cavity. Because of the danger of apical rupture and clot formation, we attempted the experimental use of alcohol ablation for effective palliation. We present our pilot experience, offer a novel interpretation of the nature of this obscure entity, and possibly justify a new catheter treatment. In addition, we discuss the developmental, pathophysiologic, and clinical implications of this unusual form of hypertrophic cardiomyopathy. To our knowledge, ours is the first reported use of subselective, modified-protocol alcohol septal ablation to treat an obstructive mid-apical muscular ring in a patient with apical hypertrophic cardiomyopathy.Key words: Cardiomyopathy, hypertrophic/complications/epidemiology/physiopathology/therapy; ethanol/administration & dosage/therapeutic use; heart septum/pathology; hypertrophy, left ventricular/diagnosis; myocardial ischemia/complications; treatment outcomeHypertrophic obstructive cardiomyopathy (HOCM) is a congenital heart condition characterized by ventricular hypertrophy and a progressive worsening of symptoms, as related to the worsening of the subaortic gradient.^1,2 Either traditional surgical septal myomectomy^3,4 or alcohol septal ablation (ASA)^2,4,5 can be used to treat HOCM by effectively reducing the subaortic gradient.^1,2 We describe the case of an elderly woman who had the rarer variant of hypertrophic cardiomyopathy (HCM)—that with apical aneurysm and mid-ventricular obstruction. We describe in detail the experimental use of subselective alcohol ablation to treat the obstructive mid-apical muscular ring in this patient, and we revisit the nature of apical HCM.     

Left ventricular diastolic function in hypertrophic cardiomyopathy: assessment by radionuclide angiography

Diastolic left ventricular function was studied in 20 patients with obstructive hypertrophic cardiomyopathy, 10 with apical hypertrophic cardiomyopathy, and 20 control subjects. The left ventricular time-activity curve was filtered using Fourier expansion with 4 harmonics. The first and second derivatives of the filtered curve were used to define various parameters of the left ventricle. Isovolumic relaxation period and time to peak filling rate were prolonged in obstructive hypertrophic cardiomyopathy and apical hypertrophic cardiomyopathy (101.56 +/- 44.81 msec, 105.19 +/- 45.27 versus 72.19 +/- 29.36 (CS) P less than 0.05; 169.70 +/- 50.73 msec, 173.83 +/- 50.53 versus 138.02 +/- 29.54 (CS) P less than 0.05, respectively). Rapid filling period, diastasis, atrial contraction period, time to peak filling rate-isovolumic relaxation period, and filling fraction of diastasis were not significantly different in these groups. Fasting filling fraction was 11% lower in hypertrophic groups than in control subjects. The filling fraction of atrial contribution was 12% higher in hypertrophic groups. We conclude: Isovolumic relaxation period, rapid filling phase, and diastasis atrial contraction period can be clearly defined by this technique. Impaired relaxation is an important determinant of decreased left ventricular filling in patients with obstructive hypertrophic cardiomyopathy and apical hypertrophic cardiomyopathy. Prolonged time to peak filling rate is mainly due to increased isovolumic relaxation period in hypertrophic patients. Atrial contraction contributes to more stroke volume in patients with hypertrophic cardiomyopathy.     

Diastolic paradoxic jet flow in patients with hypertrophic cardiomyopathy: report of two patients with different morphologic aspects

BACKGROUND: In non-Asiatic population, apical hypertrophic cardiomyopathy represents 1% to 2% of hypertrophic cardiomyopathies. The presence of an apical ventricular aneurysm occurs in 1% of patients with the apical variant of hypertrophic cardiomyopathy. METHODS AND RESULTS: We present two patients with hypertrophic cardiomyopathy, both illustrating an early diastolic paradoxic jet flow between the apex and the middle area of ventricle. Such paradoxic flow is possibly due to the coexistence of mid-chamber obliteration and segmental wall motion abnormalities at the apex. The incidence and clinical significance of this flow pattern is still to be clarified.     

Cardiac muscle cell disorganization in apical hypertrophic cardiomyopathy: a cardiac biopsy study

Apical hypertrophic cardiomyopathy has been divided into two entities: apical asymmetric septal hypertrophy (apical ASH) and apical symmetric hypertrophy (AH). The latter differs clinically from hypertrophic cardiomyopathy (HCM) with ASH, and it is unclear whether AH represents a distinct subtype of HCM. In the present study, the presence or absence and the extent of cardiac muscle cell disorganization, a histologic characteristic of HCM, were compared in patients with AH (n = 10) and ASH (n = 29) in whom cardiac biopsy specimens were obtained from the left ventricular apex and interventricular septum. Disorganization was graded as (1+) in only 1 patient in the AH group and (-) in the remaining 9. In contrast, in the ASH group disorganization was graded as (1+) in 15 patients, (2+) in 7, (3+) in 3, and (-) in only 4 (P < 0.0001). Thus, it was observed that in AH disorganization is virtually absent or at most limited to a very narrow area. It is concluded from a histological stand point as well that the type of apical hypertrophic cardiomyopathy showing apical symmetric hypertrophy differs from usual HCM.     

Necropsy finding in a patient with apical hypertrophic cardiomyopathy

Whether apical hypertrophic cardiomyopathy is a variant of classic hypertrophic cardiomyopathy or a separate entity is controversial. This is a case report of an apical hypertrophic cardiomyopathy. The patient was a 67-year-old man associated with giant negative T waves in electrocardiogram and asymmetric apical hypertrophy on echocardiogram. He died of liver cirrhosis and liver cell carcinoma. At necropsy the heart showed apical hypertrophy grossly and extensive disarray of myocardial fibers near the apex of the left ventricle histologically. The necropsy findings were indistinguishable from those of classic hypertrophic cardiomyopathy. This suggests that apical hypertrophic cardiomyopathy is a variant of hypertrophic cardiomyopathy.     

Apical hypertrophic cardiomyopathy mimicking acute coronary syndrome: a case report and review of the literature

Apical hypertrophic cardiomyopathy is a form of hypertrophic cardiomyopathy localized to the left ventricular apex. It is common in Japanese and other Asian populations, where it is generally considered relatively benign. However, its presence has also been recognized, though less commonly, in non-Asian patients. In these patients, the electrocardiographic changes and symptoms associated with apical hypertrophic cardiomyopathy often mimic acute coronary syndromes. Invasive or noninvasive evaluation of the left ventricular cavity confirms the diagnosis, with the "ace-of-spades" sign on left ventriculography being pathognomonic. Its prognosis is relatively benign in terms of cardiovascular mortality; however, morbid sequelae, such as diastolic dysfunction, left atrial enlargement, apical thrombi, ventricular aneurysms, and myocardial infarction, are not uncommon. The authors present a case of apical hypertrophic cardiomyopathy in a Caucasian patient who presented with findings suggestive of acute coronary syndrome and review the literature on apical hypertrophic cardiomyopathy.     

Hypertrophic nonobstructive cardiomyopathy with giant negative T waves (apical hypertrophy): ventriculographic and echocardiographic features in 30 patients

In 30 of 1,002 consecutive patients who had left heart catheterization and cineangiography for evaluation of either ischemic heart disease or cardiomyopathy the electrocardiogram showed giant negative T waves (greater than 10 mm) associated with high QRS voltage (R wave greater than 26 mm in lead V₅ or the sum of the S wave in lead V₁ and the R wave in lead V₅ 35 mm or more) in the precordial leads despite absence of hypertension or significant coronary artery disease. In all 30 patients a characteristic spade-like configuration (concentric apical hypertrophy) was observed in the right anterior oblique ventriculogram at end-diastole as well as in the long axis two dimensional echocardiogram.The average apical thickness in these patients (24.8 ± 6.6 mm) was significantly greater than that in normal subjects (9.4 ± 3.1 mm) (P < 0.001) or in patients with hypertrophic obstructive cardiomyopathy (14.7 ± 5.0 mm) (P < 0.001). Values for both the mid anterior free wall thickness (13.9 ± 4.1 mm) and the mid posterior free wall thickness (14.3 ± 3.0 mm) were greater than values in normal subjects (8.9 ± 1.8 mm and 8.2 ± 2.0 mm, respectively) (P < 0.001). However, the ratio between the apical and the mid anterior free wall thickness in these 30 patients (1.86 ± 0.53) was significantly greater than the ratio in normal subjects (1.05 ± 0.24), patients with hypertrophic obstructive cardiomyopathy (0.96 ± 0.15) (P < 0.001) and patients with types of nonobstructive hypertrophic cardiomyopathy (1.26 ± 0.24) (P < 0.005) other than apical concentric hypertrophy. Obstruction of the tract did not occur because the upper half of the septem remained rather thin in systole and did not bulge into the left ventricle during systole. Pressure study with proper provocations as well as two dimensional echocardiograms revealed no peak systolic pressure gradient or obstruction within the outflow tract of the left ventricle.It is concluded that these 30 patients have nonobstructive hypertrophic cardiomyopathy with marked concentric hypertrophy in the apex (apical hypertrophic type) and with a different septal shape and contraction pattern from those seen in the obstructive type. This type of hypertrophy appears to be a fairly common type of hypertrophic cardiomyopathy in Japan.     

Apical hypertrophic cardiomyopathy followed by midventricular obstruction and apical aneurysm: a case report

A 72-year-old man presented with apical hypertrophic cardiomyopathy followed by midventricular obstruction and apical aneurysm. Doppler echocardiography revealed an abnormal blood flow from the apical aneurysm to the left ventricular outflow through the obstructive lesion during diastole. Myocardial perfusion scintigraphy showed no ischemic change in the apex. This case suggests that apical aneurysm may not be caused by ischemia, although previous reports showed ischemic degeneration or fibrosis may be a cause of an apical aneurysm.     

Tissue Doppler imaging in hypertrophic cardiomyopathy: impact of intraventricular obstruction on longitudinal left ventricular function.

BACKGROUND: In non-obstructive hypertrophic cardiomyopathy, tissue Doppler imaging of the mitral annulus shows severe systolic and diastolic dysfunction, with marked heterogeneity and asynchrony. In obstructive forms, the complexity of pathophysiological interactions makes conventional echocardiographic functional assessment extremely difficult and complex. OBJECTIVE: To study longitudinal left ventricular function with tissue Doppler imaging in the obstructive forms of hypertrophic cardiomyopathy. METHODS: Twenty-six patients with hypertrophic obstructive cardiomyopathy and 23 patients with the non-obstructive form of the disease, matched by age, were studied with pulsed tissue Doppler imaging of the 4 sides of the mitral annulus (septal, lateral, inferior, anterior) in 4 and 2 chamber views. In each wave (systolic-s, rapid filling-e, atrial contraction-a) we analyzed velocities, time intervals and velocity-time integrals, as well as heterogeneity and asynchrony indexes. Data were compared between the different sides in each group, between groups and with conventional Doppler data. RESULTS: In contrast to the non-obstructive forms, patients with intraventricular obstruction showed: Systolic function: similar velocities and integrals, the relations between the different sides of the annulus usually being preserved; longer isovolumic contraction time, time to peak s and PEP/LVET. Diastolic function: similar rapid filling and e/a velocities and integrals, lower atrial contraction velocity and integral, similar number of sides with e/a higher than or equal to 1 on the lateral and inferior side of the annulus; similar diastolic time intervals, except diastolic time. CONCLUSIONS: This study shows that the presence of dynamic intraventricular obstruction and the loading conditions of obstructive forms of hypertrophic cardiomyopathy do not significantly influence most annular tissue Doppler imaging parameters, showing the relative load independence of the technique. So, in obstructive hypertrophic cardiomyopathy patients: 1--Longitudinal systolic function (velocities) is similar to the non-obstructive forms--longitudinal systolic dysfunction. 2--Longitudinal diastolic function (velocities and time intervals) is similar to the non-obstructive forms--longitudinal diastolic dysfunction. 3--Left atrial dysfunction is more severe than in non-obstructive forms. 4--The inferior and lateral sides of the annulus should be those selected in order to identify pseudonormalization of the transmitral flow.     

肥厚型梗阻性心肌病合并左室心尖部室壁瘤同期外科手术治疗的远期结果

目的研究肥厚型梗阻性心肌病合并左室心尖部室壁瘤的外科治疗效果。方法回顾性分析2012年10月至2017年7月接受外科手术治疗的8例肥厚型梗阻性心肌病合并左室心尖部室壁瘤的病例资料。男6例,女2例;年龄14~73岁,平均(38.6±19.9)岁。所有患者均接受室间隔心肌切除术和室壁瘤切除术治疗。采集患者院内的病历资料,并通过门诊及电话随访记录患者情况。结果术前全部患者均通过冠状动脉造影排除了固定的冠状动脉狭窄病变,6例患者合并左室中部梗阻,3例有室性心动过速病史。全组病例无手术死亡,4例患者治疗过程中有不同程度的并发症。术后心脏超声提示LVOTPG、IVS、LAD、MI程度与术前比较均有显著性改善(P<0.05),但术后超声提示仍有4例患者心尖部可见室壁瘤样结构。所有患者随访(47.4±24.0)个月,随访率100%,术后NYHA心功能分级明显好于术前(P=0.001),远期死亡1例。结论肥厚型梗阻性心肌病合并左室心尖部室壁瘤的患者病情危重,同期行室间隔心肌切除术和室壁瘤切除术临床结果可以接受,但一些问题仍有待进一步研究。     

Musical systolic murmur produced by oscillation of the systolic anterior motion of the mitral apparatus: relation to the genesis of Still's murmur

The genesis of a musical systolic murmur produced by systolic anterior motion (SAM) of the mitral apparatus was investigated in four patients using phonocardiography and echocardiography. Two patients (Case 1 and 3) had hypertrophic cardiomyopathy (one, the obstructive type; the other, the nonobstructive type) and the remaining two (Case 2 and 4) had redundant chordae tendineae. 1. In every patient, regular oscillation of the SAM was observed, coinciding in time with the musical systolic murmur, which was simultaneously recorded. The fundamental frequency of the musical systolic murmur was recorded as integrally multiplied numbers of the SAM. Such regular oscillation was not observed in the echograms of other cardiac structures. In a patient with hypertrophic obstructive cardiomyopathy (Case 1), both the amplitude and oscillation of the SAM were increased by amyl nitrite inhalation, and were decreased by angiotensin II infusion. Correspondingly, the intensity of the musical murmur showed similar reaction. No findings suggestive of mitral valve prolapse or mitral regurgitation were found in any patients. Therefore, the oscillation of the SAM produced by blood ejected from the left ventricle was considered the source of the musical systolic murmur in these patients. 2. Two patients with redundant chordae tendineae had no clinical abnormalities except for chordal redundancy; therefore, the musical murmur in these cases was considered to be functional. Particularly, one of them was compatible in character with the so-called Still's murmur. In conclusion, the regular oscillation of the SAM may be the source of the musical systolic murmur, and they must be taken into consideration as part of the genesis of Still's murmur.     

Clinical features of hypertrophic cardiomyopathy in the young

BACKGROUND: We analysed the experience with hypertrophic cardiomyopathy in two paediatric centres to establish the differences from older patients. METHODS: Out of 45 young patients seen from 1974 to 1999, we included 38. Criterions for exclusion were secondary forms, or association with severe congenital cardiac disease which could alter the outcome. RESULTS: The patients presented at the age of 5.7 years, and were followed for 7.0 years. The 34 patients referred because of a murmur or cardiomegaly were older than the four with heart failure, presenting at 6.2 as opposed to 2.1 years of age, p = 0.08. Of the patients, 29 (76%) had primary cardiomyopathy, while 9 (24%) had secondary forms associated with Noonan's and LEOPARD syndromes. Familial tendency was ascertained in 7 patients (18%). The septal thickness in mm/m2 at presentation was greater in patients under 2 years than in older children (29 vs 18, p = 0.02). Obstructive hypertrophic cardiomyopathy was found in 17 patients (45%), with six of these having mild associated congenital cardiac defects. Nine had symptomatic arrhythmias. Overall, treatment was medical in 31, with DDD pacing used in 5, and surgery, radiofrequency ablation, and transplantation in one patient each. Total mortality was 24%, at a rate of 4.3% per year. Four patients died in heart failure and 5 had sudden death. Those in failure were significantly younger (p = 0.01). CONCLUSIONS: Hypertrophic cardiomyopathy in the young is characterized by referral for murmur or heart failure; frequent secondary forms; the obstructive variant being as common as the non-obstructive form; a mortality rate similar to that for adults attending tertiary centres; and less frequent familial forms than in older populations.