Difference in coronary blood flow dynamics between patients with hypertension and those with hypertrophic cardiomyopathy.

We studied twelve patients with hypertensive left ventricular hypertrophy (LVH), 10 patients with hypertrophic cardiomyopathy (HCM) and 10 control subjects to examine the differences in coronary blood flow (CBF) dynamics between patients with hypertensive LVH and those with HCM. All subjects had normal coronary arteriograms. Measurements of CBF using Doppler Flo-Wire were performed at rest, and after infusions of acetylcholine and papaverine. The baseline CBF was significantly increased in both hypertensive LVH patients and HCM patients compared to that noted in control subjects (64.1+/-36.9, 80.0+/-38.1, 32.3+/-8.0 ml/min, respectively, p<0.01). Coronary flow reserve and endothelium-dependent vasodilatation were significantly lower in hypertensive LVH patients and HCM patients than in control subjects, but there was no significant difference between the hypertensive LVH and HCM patients themselves. In contrast, the diastolic/systolic velocity ratio at baseline was significantly lower in hypertensive LVH patients than in HCM patients (1.53+/-0.40, 6.31+/-7.50, p<0.05). Although CBF and coronary flow reserve correlated positively and negatively, respectively, with left ventricular mass index (r=0.51, -0.59, respectively), the diastolic/systolic velocity ratio at baseline did not show a significant correlation to left ventricular mass index. In conclusion, the diastolic/systolic velocity ratio differed between hypertensive LVH and HCM patients, independent of left ventricular mass. These results suggest that the difference of phasic pattern of CBF may be essential for coronary circulation in patients with hypertensive LVH and in those with HCM.     

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.     

An approach to echocardiography in hypertrophic cardiomyopathy and other causes of LVH

Hypertrophic cardiomyopathy (HCM) is the most prevalent genetic cardiovascular disease with a prevalence of 1:500 in the general population. Its identification is of critical importance as it is a common cause of sudden death in the young and can lead to considerable morbidity, including heart failure and atrial fibrillation. There are several conditions that can mimic the phenotypic appearance of HCM on echocardiography. Echocardiography remains an invaluable tool in both initial diagnosis and regular surveillance of patients with this condition. Although no single echocardiographic parameter is ideal, a structured and comprehensive assessment of cardiac structure and function will provide invaluable clues to the diagnosis and often hint towards an alternate diagnosis. The purpose of this review is to reassess the typical echocardiographic features of HCM and to highlight echocardiographic features that may help to distinguish other causes of left ventricular hypertrophy (LVH).     

Multiparametric electrocardiographic evaluation of left ventricular hypertrophy in idiopathic and hypertensive cardiomyopathy.

BACKGROUND: Electrophysiological abnormalities underlying the increased arrhythmogenicity of left ventricular hypertrophy (LVH) are still under investigation. The aim of this study was to assess non-invasively the electrophysiologic alterations in two different types of LVH, METHODS: Multiparametric non-invasive ECG analysis (R-R interval, QRS and QT intervals, QT dispersion, T-wave complexity, activation-recovery interval [ARI] dispersion, standard deviation of RR intervals [SDNN], filtered QRS duration [fQRS], root-mean-square voltage of the terminal 40 ms of the fQRS [RMS40] and low amplitude signal duration (< 40 microV) in the terminal portion of the fQRS [LAS]) was performed in 57 patients with hypertensive LVH and hypertrophic cardiomyopathy (HCM), and in 105 healthy subjects. RESULTS: The R-R interval and SDNN were similar in hypertrophic patients and controls. QRS and QT intervals were longer in hypertrophic patients without any differences between hypertensive LVH and HCM. QT dispersion, T-wave complexity and fQRS were greater in hypertrophic patients; QT dispersion was the greatest in HCM. ARI dispersion was lesser in hypertrophic patients without any differences between subgroups of LVH. fQRS showed a trend toward higher values in hypertensive patients. LAS at 25 Hz had a trend toward lower values in HCM patients, while LAS at 40 Hz and RMS40 showed no difference between controls and hypertrophic patients. Left ventricular mass index was not correlated with any of the above-mentioned parameters. CONCLUSIONS: The QT interval and dispersion did not identify the type of hypertrophy. Similarly, ARI dispersion which explores local variations of repolarization duration, and T-wave complexity could not distinguish patients with hypertensive LVH from those with HCM indicating that multiparametric ECG data are affected more by the presence of LVH, than by its type.     

Hypertrophic cardiomyopathy is associated with abnormal echocardiographic aortic elastic properties and arteriograph-derived pulse-wave velocity

Objective: Hypertrophic cardiomyopathy (HCM) is a genetic cardiac disease and defined by the presence of unexplained left ventricular hypertrophy (LVH). Vascular alterations are frequently associated with HCM including microvascular and/or peripherial endothelial dysfunction. This study was designed to evaluate echocardiographic ascending aortic elastic properties and arteriograph‐derived pulse‐wave velocity (PWV) and augmentation index (Aix) in HCM. Methods: This study comprised 38 patients with typical features of HCM. Their results were compared to 20 hypertensive patients with LVH and 23 controls. Systolic and diastolic ascending aortic diameters were recorded in M‐mode at a level of 3 cm above the aortic valve from a parasternal long‐axis view. The following echocardiographic aortic elastic properties were measured from aortic data and forearm blood pressure values: aortic strain, distensibility, and stiffness index. Arteriograph‐derived PWV and AIx were also measured. Results: Aortic stiffness index (18.4 ± 17.6 vs. 6.88 ± 3.63, P < 0.05), PWV (9.44 ± 4.08 vs. 7.97 ± 1.20 m/sec, P < 0.05) and Aix (‐24.9 ± 32.6 vs. –41.4 ± 24.3, P < 0.05) were increased, while aortic strain (0.061 ± 0.053 vs. 0.100 ± 0.059, P < 0.05) and aortic distensibility (1.94 ± 1.68 cm²/dynes 10^?6 vs. 3.08 ± 1.77 cm²/dynes 10^?6, P < 0.05) were decreased in HCM patients compared to controls. Aortic elastic properties of hypertensive patients with LVH showed similar alterations to HCM patients. Conclusions: Abnormal echocardiographic aortic elastic properties and arteriograph‐derived PWV and Aix could be demonstrated in HCM patients compared to matched controls. (Echocardiography 2011;28:848‐852)     

Ultrasonic tissue characterization in hypertrophic cardiomyopathy: analysis of three-layered appearance of the ventricular septum by apical approach]

In normal hearts, two-dimensional echocardiography from the apical window displays the left ventricular wall as a three-layered appearance (TLA): central bright layer and bilateral sonolucent zones. The TLA is considered to reflect the normal myocardial architecture: the predominant latitudinal fiber bundles of the midwall layer, and longitudinal or oblique ones on both sides. We analysed the TLA of the ventricular septum in 20 normal subjects, 20 patients with left ventricular hypertrophy due to pressure load (LVH), and 81 patients with hypertrophic cardiomyopathy (HCM). Of the 81 HCM patients, the layering was often obscure or absent in 53 (65%), whereas LVH patients showed clear TLA as well as normal hearts. In patients with severe layering disorder (n = 30), the age at diagnosis was lower (40 +/- 15 vs 50 +/- 12, p less than 0.05), and familial occurrence (53 vs 11%, p less than 0.01) and severe functional limitation (NYHA greater than or equal to III) were more common (27 vs 4%) than in those with clear TLA (n = 28). The disturbed layering detectable by echocardiography may reflect the disorder of basic myocardial fiber architecture in the ventricular septum, and is likely to become a useful marker of the pathologic severity of the disease.     

Progression to the dilated phase of hypertrophic cardiomyopathy in children

Twenty-three children with hypertrophic cardiomyopathy (HCM) (aged 2 months to 15 years) were followed up for more than four years using thallium myocardial imaging (TMI) and echocardiography. With echocardiography, the left ventricular end-diastolic dimension (LVDd) and fractional shortening (FS) were measured. Perfusion defect (PD) was assessed using TMI. Cardiac catheterization and right ventricular endomyocardial biopsy were performed in 18 patients within one week before or after their TMI. During the follow-up period, two patients showed a marked increase in LVDd and a marked decrease in FS at ages 13 and 16 years, respectively. These two patients were judged to have progressed to the dilated phase. In these two patients, extensive PD was detected in the left ventricular wall on TMI, 15 and 31 months prior to the appearance of the echocardiographic changes, respectively. Right ventricular endomyocardial biopsy at the time of extensive PD revealed marked interstitial fibrosis along with hypertrophy and disarray of myocardial cells. In conclusion, progression to the dilated phase is not a rare event in children with HCM and TMI appears to be a useful tool for early detection of the progression.     

Ventricular arrhythmias in hypertensive left ventricular hypertrophy. Relationship to coronary artery disease, left ventricular dysfunction, and myocardial fibrosis

Ventricular arrhythmias occur with increased frequency in hypertensive patients with left ventricular hypertrophy (LVH). The relationships, however, between ventricular arrhythmias and coexistent coronary artery disease, left ventricular dysfunction and left ventricular fibrosis have not been examined in hypertensive LVH. We carried out coronary arteriography on fifteen hypertensive patients with LVH and nonsustained ventricular tachycardia (greater than or equal to 3 consecutive ventricular complexes) of whom nine (60%) were free of significant (greater than 50% stenosis) coronary disease. To identify other possible correlates of left ventricular arrhythmias, 28 patients with LVH, comprising 17 with ventricular tachycardia and 11 without ventricular arrhythmias, underwent quantitative assessment of left ventricular function (angiographic ejection fraction), left ventricular mass (echocardiography), and left ventricular fibrosis (endomyocardial biopsy). Ejection fraction was not significantly different between the two groups (53 +/- 8% v 62 +/- 2%, P = NS). However, left ventricular mass was significantly greater (442 +/- 28 g v 339 +/- 34 g, P less than .05) and percentage fibrosis significantly higher (19 +/- 4% v 3 +/- 1%, P less than .001) in those patients with ventricular tachycardia. Thus ventricular arrhythmias in hypertensive patients with LVH cannot be entirely attributed to coexistent coronary disease, nor to left ventricular dysfunction, but are related to the degree of cardiac hypertrophy and subendocardial fibrosis.     

Assessment of global and regional left ventricular diastolic function in hypertensive heart disease using automated border detection techniques

Acoustic quantification (AQ) and color kinesis (CK) are techniques that involve automated detection and tracking of endocardial borders. These methods are useful for the evaluation of global and regional left ventricular (LV) systolic function and more recently have been applied to evaluating LV diastolic performance. Assessment of diastolic dysfunction in hypertensive heart disease is a relevant clinical issue in which these techniques have proven useful. The diastolic portion of left atrium and LV AQ area waveforms are frequently abnormal in patients with left ventricular hypertrophy (LVH). Left ventricular AQ curves consistently demonstrate reduced rapid filling fraction (RFF) and peak rapid filling rate (PRFR), elevated atrial filling fraction (AFF), peak atrial filling rate (PAFR), and reductions in the ratio PRFR/PAFR. Acoustic quantification complements traditional Doppler echocardiographic evaluation of global diastolic function. Many patients with significant LVH and normal Doppler diastolic parameters can be identified as having diastolic dysfunction with AQ. In addition, CK has allowed the evaluation of regional diastolic performance in hypertensive patients. Regional filling curves obtained from CK have demonstrated that endocardial diastolic motion is commonly delayed and heterogeneous in patients with LVH.     

Expression and distribution of atrial natriuretic peptide in human hypertrophic ventricle of hypertensive hearts and hearts with hypertrophic cardiomyopathy.

To investigate the ventricular expression of atrial natriuretic peptide (ANP) in human hypertrophic hearts, we conducted an immunohistochemical study of 130 endomyocardial biopsy specimens obtained from the right side of the ventricular septum (RVB), left ventricular free wall (LVB), or both from a total of 80 patients: 44 patients with hypertrophic cardiomyopathy (HCM), 14 with apical hypertrophic cardiomyopathy (APH), 13 with hypertensive hearts (HHD), and nine without hypertrophy (controls). No patients had apparent congestive heart failure. ANP was not seen in ventricular myocytes in controls but was identified in biopsy specimens of hypertrophic hearts, and its distribution was characteristic in each hypertrophic group: 15 RVB (37%) and two LVB (7%) of the HCM group, one RVB (7%) and two LVB (18%) of the APH group, and zero RVB (0%) and five LVB (46%) of the HHD group. Clinical data (including echocardiographic, hemodynamic, and angiographic data) were not directly related to ventricular ANP expression in HCM, APH, or HHD with one exception. In HHD patients, LVB specimens with ANP showed greater ventricular wall thickness than LVB specimens without ANP. According to histological data, however, the ANP-present RVB specimens of HCM or ANP-present LVB specimens of HHD had greater myocyte size than did the ANP-absent specimens. In addition, in HCM patients, the ANP-present RVB specimens showed more severe fibrosis and myofiber disarray than did the ANP-absent specimens. We conclude that a failing state and hemodynamic overload are not likely to be indispensable for ANP expression in human hypertrophic ventricles and that ventricular ANP expression occurs as a response to disease-specific changes: hemodynamic overload in HHD and histological changes such as myocardial fiber disarray, hypertrophy of myocytes, and fibrosis in HCM, which may reflect the characteristic distribution of intraventricular ANP.     

Hypertrophic cardiomyopathy is associated with more severe left ventricular dyssynchrony than is hypertensive left ventricular hypertrophy

OBJECTIVE: To evaluate left ventricular (LV) dyssynchrony in patients with left ventricular hypertrophy (LVH), and to compare abnormalities associated with hypertrophic cardiomyopathy (HCM) and hypertensive heart disease (HHD) using 2D speckle tracking imaging. METHODS: Basal, middle, and apical 2D LV short-axis images were acquired in 43 patients with LVH including 20 with HCM and 23 with HHD, and in 15 age-matched controls. Radial strain, circumferential strain, time interval from the R-wave to peak radial strain (Trs), and time to peak circumferential strain (Tcs) were measured in six equidistant segments at each level of the 3 LV short-axis views using 2D speckle tracking analysis. To assess LV dyssynchrony, Trs(cs)-18SD, the standard deviation (SD) of Trs(cs) in all 18 segments, was calculated. RESULTS: Regional radial strain in the middle and apical short-axis segments was significantly less in patients with HCM than in those with HHD. Regional circumferential strain in the apical short-axis segments was also less in HCM. Trs-18SD and Tcs-18SD were significantly longer in patients with HCM than in age-matched controls and patients with HHD (Trs-18SD: HCM: 88 +/- 32 ms, HHD: 51 +/- 20 ms, control: 45 +/- 12 ms P < 0.001, Tcs-18SD: HCM: 71 +/- 27 ms, HHD: 46 +/- 14 ms, control: 45 +/- 14 ms P < 0.001). CONCLUSIONS: The presence of LVH is thus not always associated with LV dyssynchrony. However, the greater reduction of regional strain and severe LV dyssynchrony in HCM may contribute to the adverse cardiovascular outcomes associated with this disease.     

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.     

New insights in cardiac structural changes in patients with Fabry's disease

BACKGROUND: Fabry's disease is an X-linked recessive genetic deficiency of the enzyme alpha-galactosidase leading to the pathologic intracellular deposition of neutral glycosphingolipids. Although cardiac involvement is frequent, there is controversy regarding the character of the associated left ventricular (LV) changes and the severity of valvular involvement. METHODS: Clinical evaluation (disease severity scaling, laboratory tests, and echocardiography) was performed in 13 hemizygous men (mean age 39 +/- 10 years) and 17 heterozygous women (mean age 35 +/- 19 years). RESULTS: LV hypertrophy (LVH) was frequent in subjects older than 30 years, more often in men (61%) than in women (18%, P <.001). The degree of LVH was independently associated with age and the logarithm of alpha-galactosidase activity (r(2) = 0.70, P <.001). The predominant LV geometric patterns were concentric LVH and remodeling, both present in 11 subjects (36%). Three patients had an asymmetric septal hypertrophy mimicking hypertrophic cardiomyopathy. In most subjects with LVH, the systolic function was normal and severe diastolic dysfunction (restrictive pattern) was not noted. Minor structural abnormalities of the mitral valve were found in 17 subjects (57%). The aortic valve was affected in 14 patients (47%). Valvular abnormalities were frequently accompanied by regurgitation of minor to mild degree. The presence of LVH or valvular changes was associated with increased disease severity. CONCLUSIONS: Echocardiographically detectable cardiac involvement is frequent with Fabry's disease, particularly in older subjects, and more pronounced in affected hemizygous men than in heterozygous women. LVH is frequently observed but usually not associated with significant systolic or restrictive diastolic dysfunction. Concentric LVH and remodeling appear to be the major manifestations of LV structural alteration. The frequently noted valvular abnormalities were not associated with a significant degree of regurgitation. Valvular and especially LV structural changes may serve as a useful marker of disease severity.     

Development of left ventricular hypertrophy in adults in hypertrophic cardiomyopathy caused by cardiac myosin-binding protein C gene mutations

OBJECTIVES: We sought to determine whether the development of left ventricular hypertrophy (LVH) can be demonstrated during adulthood in genetically affected relatives with hypertrophic cardiomyopathy (HCM). BACKGROUND: Hypertrophic cardiomyopathy is a heterogeneous cardiac disease caused by mutations in nine genes that encode proteins of the sarcomere. Mutations in cardiac myosin-binding protein C (MyBPC) gene have been associated with age-related penetrance. METHODS: To further analyze dormancy of LVH in patients with HCM, we studied, using echocardiography and 12-lead electrocardiography, the phenotypic expression caused by MyBPC mutations in seven genotyped pedigrees. RESULTS: Of 119 family members studied, 61 were identified with a MyBPC mutation, including 21 genetically affected relatives (34%) who did not express the HCM morphologic phenotype (by virtue of showing normal left ventricular wall thickness). Of these 21 phenotype-negative individuals, 9 were children, presumably in the prehypertrophic phase, and 12 were adults. Of the 12 adults with normal wall thickness < or = 12 mm (7 also with normal electrocardiograms), 5 subsequently underwent serial echocardiography prospectively over four to six years. Of note, three of these five adults showed development of LVH in mid-life, appearing for the first time at 33, 34 and 42 years of age, respectively, not associated with outflow obstruction or significant symptoms. CONCLUSIONS: In adults with HCM, disease-causing MyBPC mutations are not uncommonly associated with absence of LVH on echocardiogram. Delayed remodeling with the development of LVH appearing de novo in adulthood, demonstrated here for the first time in individual patients with prospectively obtained serial echocardiograms, substantiates the principle of age-related penetrance for MyBPC mutations in HCM. These observations alter prevailing perceptions regarding the HCM clinical spectrum and family screening strategies and further characterize the evolution of LVH in this disease.     

Epidemiologic and clinical characteristics of cardiomyopathies in Japan: results from nationwide surveys.

Nationwide clinico-epidemiological surveys of cardiomyopathies in Japan were carried out. Disorders surveyed included idiopathic dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), restrictive cardiomyopathy (RCM), arrhythmogenic right ventricular dysplasia (ARVD), mitochondrial disease, Fabry's disease of the heart and prolonged Q-T interval syndrome. The total number of patients was estimated at 17,700 for DCM, 21,900 for HCM, 300 for RCM, 520 for ARVD, 640 for mitochondrial disease, 150 for Fabry's disease of the heart, and 1,000 for prolonged Q-T interval syndrome. The prevalence of both DCM and HCM was higher in men than women: the male-to-female ratios were 2.6 and 2.3 for DCM and HCM, respectively. Detailed data on patients with DCM or HCM were collected by a follow-up survey. In 1 year more patients with DCM (5.6%) died than with HCM (2.8%): congestive heart failure (CHF) and arrhythmias were the leading causes of death for DCM and HCM, respectively. Angiotensin converting enzyme inhibitors (64.6%) and beta-adrenergic blockers (40.9%) are commonly used to treat the CHF complicating DCM and may be associated with the clinical improvement in a significant number of DCM patients. Thus, the nationwide surveys of Japanese patients have yielded important current epidemiological and clinical information on the characteristics of cardiomyopathies in Japan.     

Morphological quantification and differentiation of left ventricular hypertrophy in hypertrophic cardiomyopathy and hypertensive heart disease. A two dimensional echocardiographic study

Differentiation between hypertrophic cardiomyopathy and hypertensive heart disease is a diagnostic challenge. M-mode echocardiography only permits assessment of hypertrophy in limited areas of the left ventricular wall. 2-D echocardiography allows visualization of most of the myocardium. To assess the reliability of conventional M-mode echocardiographic and 2-D echocardiographic criteria in patients with hypertrophic cardiomyopathy (HCM) and hypertensive heart disease (HY), 30 patients with hypertrophic cardiomyopathy and 30 patients with hypertension and severe cardiac hypertrophy were examined using M-mode and 2-D echocardiography. Although the M-mode echocardiographic features showed statistically significant differences between the mean values in the two groups, the degree of overlap made the differentiation of the individual patients difficult. The diagnostic sensitivity and specificity of classic echocardiographic features were assessed: ventricular septal thickness greater than or equal to 1.5 cm, 90% and 43% (sensitivity and specificity, respectively); ventricular septal thickness to posterior wall ratio greater than or equal to 1.5, 83% and 56%; cross-sectional area at papillary level greater than 21 cm2m-2, 80% and 73%; septal segment of the myocardial ring at papillary level greater than 6.5 cm2m-2, 80% and 87%; and the combined criteria of cross-sectional area at papillary level greater than 21 cm2m-2 and septal segment greater than 6.5 cm2m-2, 77% and 93%. Quantitative 2-D echocardiography is useful to differentiate patients with hypertrophic cardiomyopathy from those with secondary myocardial hypertrophy due to hypertension. Hypertrophic cardiomyopathy is characterized by a spectrum of different morphological patterns of hypertrophy. Patients with the predominant region of hypertrophy in the anterolateral free wall or the apical region of the left ventricle were not detected with our quantitative method. Patients with this type of hypertrophy are relatively rare in the western population.     

A patient with hypertrophic cardiomyopathy accompanied by right ventricular dilation of unknown cause

Hypertrophic cardiomyopathy (HCM) is a disease characterized by an unknown cause of hypertrophy in the left or right ventricle. The dilated phase of HCM shows disease conditions resembling dilated cardiomyopathy, such as ventricular dilation, thin ventricular wall, and reduction of the ejection fraction. A patient presented with left ventricular concentric hypertrophy accompanied by right ventricular dilatation of unknown cause. Right ventricular endomyocardial biopsy specimens showed characteristic myocardial disarray. Therefore, there is the possibility that the patient had right and left ventricular HCM in the process toward the dilated phase, in which dilatation first occurred in the right ventricle.     

Fabry disease: percutaneous transluminal septal myocardial ablation markedly improved symptomatic left ventricular hypertrophy and outflow tract obstruction in a classically affected male

Fabry disease (alpha-galactosidase A deficiency) is an X-linked recessive lysosomal storage disease in which left ventricular hypertrophy (LVH) is common, and if severe, may mimic hypertrophic obstructive cardiomyopathy. Alcohol-induced percutaneous transluminal septal myocardial ablation (PTSMA) has been used as a safe and effective method to alleviate LVH obstruction in patients with hypertrophic obstructive cardiomyopathy (HCM). We describe a case of a classically affected Fabry 53-year-old male with symptomatic HCM (NYHA class III with exertional angina) who was treated with PTSMA. The procedure safely and effectively alleviated symptomatic left ventricular outflow tract obstruction at long-term follow-up, and the patient's NYHA classification was reduced to NYHA class I to II.     

Body surface distribution of abnormally low QRST areas in patients with left ventricular hypertrophy. An index of repolarization abnormalities.

BACKGROUND. QRST isointegral maps (I-maps) have been useful in detecting repolarization abnormalities. We investigated the body surface distribution of abnormally low QRST areas in patients with left ventricular hypertrophy (LVH) and the relation of the abnormalities in I-map to the severity of LVH as assessed by echocardiography. METHODS AND RESULTS. QRST area departure maps were constructed from electrocardiographic (ECG) data recorded in patients with LVH and precordial negative T waves resulting from aortic stenosis (AS) (10 patients), aortic regurgitation (AR) (12 patients), or hypertrophic cardiomyopathy (HCM) with asymmetric septal hypertrophy (22 patients). Fifty normal subjects served as controls. The I-map was constructed from 87 body surface electrocardiograms recorded simultaneously at a sampling interval of 1 msec. The area where the QRST area was smaller than normal limits (mean -2 SD) was designated the "-2 SD area." The echocardiographic left ventricular (LV) mass was calculated by Devereux's method. Patients with large LV masses due to AS or AR had 2 SD areas located over the left anterior chest or the midanterior chest, respectively. The 2 SD area was located over the left shoulder and left anterior chest and had a lingual shape in patients with HCM. The sum of QRST area values less than the normal range (sigma QRST) was significantly correlated with LV mass in patients with AS or AR (r = 0.83 and r = 0.69, p less than 0.01 and p less than 0.05). However, there was no significant correlation between sigma QRST and the severity of LVH in patients with HCM. sigma QRST divided by the number of electrodes in the 2 SD area was significantly greater in patients with HCM than in those with AS or AR. CONCLUSIONS. These findings suggest that abnormalities in patients with HCM are manifest even in mild LVH and that there is a greater disparity of repolarization in hypertrophied left ventricles due to HCM than in LVH due to aortic valve disease. QRST isointegral departure maps may provide ECG evidence of LV mass of patients with AS or AR and of susceptibility to malignant arrhythmias in patients with HCM.     

Basic echocardiographic features of patients with latent left ventricular outflow tract obstruction without left ventricular hypertrophy

Left ventricular outflow tract obstruction (LVOTO) is commonly observed in patients with hypertrophic cardiomyopathy (HCM) or left ventricular hypertrophy (LVH). While some patients develop LVOTO at rest, it can also be provoked by physical exertion, and hence termed latent LVOTO (L-LVOTO). Recent reports demonstrated that L-LVOTO develops not only in LVH patients, but also in patients without LVH (non-LVH). However, the prevalence and clinical prognosis of non-LVH patients with L-LVOTO are not yet elucidated. In this study, we retrospectively investigated the echocardiographic features of patients with malignancy who underwent dobutamine stress echocardiography (DSE) to evaluate preoperative cardiac risk. One hundred ninety-nine patients were found not to have LVH or coronary artery disease. Among them, 106 patients exhibited L-LVOTO after DSE. We next compared the baseline echocardiographic features of L-LVOTO (+) patients with those of L-LVOTO (-) patients, and identified the left ventricular outflow tract (LVOT) ratio (systolic LVOT diameter/diastolic LVOT diameter) as a significant predictor of L-LVOTO. An LVOT ratio ≤ 0.83 was the best cutoff value to detect the presence of L-LVOTO, with a sensitivity of 81.1% and specificity of 80.6%. Overall, L-LVOTO was found to develop in almost half of non-LVH patients with malignancy. In addition, the baseline LVOT ratio was strongly related to the presence of L-LVOTO in non-LVH patients. Therefore, patients with dynamic LVOT narrowing may benefit from DSE to detect the presence of L-LVOTO.