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1.
Relatively few clinical studies have investigated the role of MRI in the patients with hypertrophic cardiomyopathy. To assess MR capabilities in defining the presence, distribution and severity of left ventricular hypertrophy, the prevalence and clinical correlations of right ventricular hypertrophy and the prevalence and clinical implications of structural myocardial abnormalities, MRI and echocardiography were performed on 37 unselected patients with hypertrophic cardiomyopathy. The two methods were in agreement in 100% of cases in diagnosing the disease and classifying left ventricular hypertrophy as asymmetric, concentric or apical, and in 92% of cases in assessing the topographic distribution of hypertrophy of ventricular segments. A statistically significant linear correlation was found between echocardiographic and MR measurements of interventricular septum (r = 0.69, p < 0.0001, SEE = 4) and left posterior wall of the left ventricle (r = 0.67, p < 0.0001, SEE = 2.4). Right ventricular hypertrophy (right anterior wall diastolic thickness > 5 mm) was demonstrated by MRI in 23 of 33 patients (70%). In this group, left posterior wall thickness and left atrial diameter were higher (15 +/- 4 vs 11 +/- 2, p < 0.01 and 45 +/- 9 vs 38 +/- 5 mm, p < 0.05, respectively). On T2-weighted sequences, areas of reduced signal intensity, probably due to myocardial fibrosis, were detected in 16 cases (43%). This group was characterized by higher max. septal thickness (25 +/- 7 vs 21 +/- 6 mm, p < 0.05) and max. left posterior wall thickness (15 +/- 9 vs 7 +/- 8 mm, p < 0.05). All the three cases with dilated and hypokinetic left ventricle showed this kind of tissue abnormality. In conclusion, MRI provided clear, accurate and exhaustive data on the presence and distribution of left ventricular hypertrophy in hypertrophic cardiomyopathy. Right ventricular hypertrophy and structural abnormalities of ventricular myocardium can also be detected and quantified. Right ventricular involvement is associated with more severe hypertrophy of left ventricular posterior wall. Structural myocardial abnormalities, probably due to fibrosis, are related to the extent of left ventricular hypertrophy.  相似文献   

2.
Left ventricular dilation and systolic dysfunction develop in 14-16% of patients with hypertrophic cardiomyopathy. Such findings may easily be misdiagnosed as dilated cardiomyopathy. It is unknown whether left ventricular dilatation and systolic dysfunction in patients with hypertrophic cardiomyopathy are reversible. A 35-year-old man had been a heavy drinker for 13 years and was abstinent for 1 year. Five years previously he suffered cardiac arrest and, based on echocardiographic, radionuclide, and cardiac catheterization findings, the diagnosis of alcohol-induced dilated cardiomyopathy was established. At presentation the heart was of normal size, with concentric left ventricular hypertrophy and only slightly reduced systolic function. Hypertrophic cardiomyopathy was diagnosed since no other cause for left ventricular hypertrophy could be detected. In hypertrophic cardiomyopathy, alcohol may induce reversible systolic dysfunction and left ventricular dilatation.  相似文献   

3.
Non-sustained ventricular tachycardia on Holter and syncope have been considered risk factors for sudden death in hypertrophic cardiomyopathy. AIMS: In these patients the coronary vasodilator reserve is impaired despite normal coronaries, so we evaluated the correlation between the severity of coronary vasodilator reserve impairment and the occurrence of syncope and non-sustained ventricular tachycardia. METHODS AND RESULTS: Eighty-four patients with hypertrophic cardiomyopathy (62 males, age 43 +/- 12 years) had a two-dimensional echocardiographic study and a 48-h Holter. Myocardial blood flow was measured by positron emission tomography, at baseline and after dipyridamole, and the coronary vasodilator reserve was computed as dipyridamole myocardial blood flow/baseline myocardial blood flow. In 27 patients, subendocardial and subepicardial myocardial blood flow was measured in the septum and the subendocardial/subepicardial ratio was computed. Twenty of 84 patients had at least one syncopal episode, and 26 had at least one run of non-sustained ventricular tachycardia on Holter. Baseline and dipyridamole myocardial blood flow, coronary vasodilator reserve, and baseline and dipyridamole subendocardial/subepicardial myocardial blood flow ratio were similar in patients with and without syncope and with and without non-sustained ventricular tachycardia on Holter. However, patients with non-sustained ventricular tachycardia had larger left ventricular end-diastolic (47 +/- 6 vs 44 +/- 5 mm, P < 0.05) and end-systolic diameters (30 +/- 6 vs 27 +/- 4 mm, P < 0.05). CONCLUSIONS: (1) Coronary vasodilation is not more severely impaired in patients with hypertrophic cardiomyopathy and syncope or non-sustained ventricular tachycardia. (2) The left ventricle is more dilated in hypertrophic cardiomyopathy with non-sustained ventricular tachycardia.  相似文献   

4.
OBJECTIVE: Our purpose was to determine echocardiographic trends after initial diagnosis of peripartum cardiomyopathy. STUDY DESIGN: Nine women diagnosed with peripartum cardiomyopathy were prospectively recruited for a longitudinal echocardiographic study. Severe myocardial dysfunction was defined as left ventricular end-diastolic dimension > or = 60 mm + fractional shortening < or = 21%, and mild dysfunction was defined as left ventricular end-diastolic dimension < 60 mm + fractional shortening 22% to 24%. Unpaired t tests were used to compare sample means and Fisher's exact test used to compare discrete variables. RESULTS: All women were seen initially for pulmonary edema. Echocardiography showed decreased systolic function in all women. The mean age at diagnosis was 33.0 +/- 6.9 years. All but one woman had a diagnosis of either chronic hypertension (n = 6) or preeclampsia (n = 2). Four women were first seen ante partum and five post partum (range 1 day to 2 months). Repeat echocardiography was performed in all nine women (median 8 months, range 6 weeks to 5 years). There was no correlation between antepartum or postpartum presentation and cardiovascular status on follow-up (p = 0.3). Values for initial left ventricular end-diastolic dimension, severe versus mild dysfunction (68.3 +/- 7.2 mm vs 55.0 +/- 4.2 mm, p = 0.046), follow-up left ventricular end-diastolic dimension, severe versus mild (68.7 +/- 4.1 mm vs 52.0 +/- 5.7 mm, p = 0.002), and follow-up fractional shortening, severe versus mild (14.6% +/- 5.0% vs 28.5% +/- 9.2%, p = 0.02) are significant. Six of the seven women with severe dysfunction had stable disease in follow-up and one is awaiting heart transplant. One of the two women with mild dysfunction had disease resolution and one had stable disease. CONCLUSION: Patients with severe myocardial dysfunction due to peripartum cardiomyopathy are unlikely to regain normal cardiac function on follow-up.  相似文献   

5.
AIM: The purpose of the study was to analyse echocardiographic, electrocardiographic and clinical variables in patients with hypertrophic cardiomyopathy, as well as to compare the possible differences between the non-obstructive (NOHCM) and the obstructive form (OHCM). METHOD: 44 consecutive patients were studied and diagnosed with hypertrophic cardiomyopathy (NOHCM 26 and OHCM 18). The following variables were analysed: 1) echocardiographic: right ventricle (RV), interventricular septum (IVS), posterior wall (pW), telediastolic and telesystolic diameter of the left ventricle (TDD-LV and TSD-LV), size of the left atrium (LA), systolic anterior motion of the mitral valve (SAM), mitral insufficiency and direction of the jet (MI and MIpW), mitral anular calcium (MAC), filling pattern (A > E); 2) electrocardiographic: repolarization disorders (RD), left ventricular hypertrophy (LVH), negative "T" waves in the precordial leads (T-), pathological "q" waves, super or ventricular arrhythmias (SA or VA), short PR, right or left bundle branch block (RBBB and LBBB), and 3) clinical: presence of dyspnea, angina, syncope, palpitations and response to treatment with beta-blockers (B-b) or Calcium-antagonists (C-A). RESULTS: There were no differences in age or sex between the obstructive and non-obstructive groups: 1) echocardiographic differences: there were none in RV, pW, TDD-LV, LA nor A > E wave. Significant differences were found (p < 0.05) in the rest of the variables; IVS (16 +/- 3 mm in NOHCM vs 22 +/- 5 mm in OHCM), TSD-LV (26 +/- 5 mm in NOHCM vs 22 +/- 6 mm in OHCM), SAM (38% in NOHCM vs 89% in OHCM), MI (19% in NOHCM vs 78% in OHCM), MIpW (20% in NOHCM vs 79% in OHCM), MAC (15% in NOHCM vs 44% in OHCM); 2) electrocardiographic differences: there were none in the presence of RD, pathological "q", VA, short PR, RBBB nor LBBB. The presence of "T" negatives was on the limit of significance in the precordial leads (31% in NOHCM vs 11% in OHCM; p = 0.09). Differences were found in the rest of the variables; LVH (58% in NOHCM vs 83% in OHCM), SA (50% in NOHCM vs 17% in OHCM); 3) clinical differences: there were none in the presence of dyspnea, angina, syncope or palpitations. Differences were found in the improvement with treatment; B-b (60% in NOHCM vs 57% in OHCM), C-A (100% in NOHCM vs 100% in OHCM). CONCLUSIONS: 1) in our patients, the most frequent cardiomyopathy is the non-obstructive one, with no predominance of age or sex; 2) in OHCM, IVS is much wider, with smaller TSD-LV, there is a greater incidence of MI, generally directed towards the posterior wall of the left atrium, and a larger tendency to calcify the mitral annulus; 3) the most frequent electrocardiographic abnormality is the alteration of repolarization. NOHCM has a greater incidence of SA and a lower degree of LVH with more prevalence of negative "T" waves in the precordial leads; 4) there are no clinical parameters differentiating the two groups, although the sustained improvement obtained with treatment is more likely to be produced by the calcium-antagonists than by beta-blockers in both types of cardiomyopathy.  相似文献   

6.
AIMS: To assess prospectively the value of cardiac magnetic resonance imaging in patients with apparently idiopathic premature contractions arising from the right ventricular outflow tract. METHODS: We compared magnetic resonance imaging scans in 19 patients (13 males and six females, mean age 44 years) with frequent (> 100 per hour), monomorphic (left bundle branch block and inferior axis morphology) extrasystoles, and in 10 volunteers (four males and six females, mean age 36.7 years) without structural heart disease. Magnetic resonance imaging studies (1 or 1.5 Tesla) included spin-echo and gradient-echo sequences in the standard planes. The presence of structural and dynamic abnormalities of the right and left ventricles, such as reduced wall thickness, systolic bulging, and decreased systolic thickening, were evaluated. In addition, end-diastolic diameters of the right ventricular outflow tract were measured in the transverse plane. RESULTS: The dimensions of the right ventricular outflow tract were wider in patients with extrasystoles compared to the control group. Mean anteroposterior and transverse diameters were 39.6 +/- 4.6 mm vs 29.9 +/- 4.8 mm (P < 0.01) and 27.5 +/- 3.8 mm vs 20.5 +/- 2.5 mm (P < 0.01), respectively. Wall motion and morphological abnormalities were present in 16/19 (84%) patients, and were confined to the anterolateral wall in 15/16 cases. All normal subjects had normal magnetic resonance imaging findings (P = 0.008). CONCLUSIONS: Cardiac magnetic resonance imaging revealed that in patients with idiopathic right ventricular outflow tract premature contractions there was a higher rate of morphological and functional abnormalities of the right ventricular outflow tract than in the normal subjects. Large studies and long follow-up are needed to confirm whether these findings could help identify a localized form of arrhythmogenic cardiomyopathy, and its clinical significance.  相似文献   

7.
OBJECTIVES: We studied the clinical and genetic features of familial hypertrophic cardiomyopathy (FHC) caused by an Asp175Asn mutation in the alpha-tropomyosin gene in affected subjects from three unrelated families. BACKGROUND: Correlation of genotype and phenotype has provided important information in FHC caused by beta-cardiac myosin and cardiac troponin T mutations. Comparable analyses of hypertrophic cardiomyopathy caused by alpha-tropomyosin mutations have been hampered by the rarity of these genetic defects. METHODS: The haplotypes of three kindreds with FHC due to an alpha-tropomyosin gene mutation, Asp175Asn, were analyzed. The cardiac histopathologic findings of this mutation are reported. Distribution of left ventricular hypertrophy in affected members was assessed by two-dimensional echocardiography, and patient survival rates were compared. RESULTS: Genetic studies defined unique haplotypes in the three families, demonstrating that independent mutations caused the disease in each. The Asp175Asn mutation caused cardiac histopathologic findings of myocyte hypertrophy, disarray and replacement fibrosis. The severity and distribution of left ventricular hypertrophy varied considerably in affected members from the three families (mean maximal wall thickness +/- SD: 24 +/- 4.5 mm in anterior septum of Family DT; 15 +/- 2.7 mm in anterior septum and free wall of Family DB; 18 +/- 2.1 mm in posterior septum of Family MI), but survival was comparable and favorable. CONCLUSIONS: Nucleotide residue 579 in the alpha-tropomyosin gene may have increased susceptibility to mutation. On cardiac histopathologic study, defects in this sarcomere thin filament component are indistinguishable from other genetic etiologies of hypertrophic cardiomyopathy. The Asp175Asn mutation can elicit different morphologic responses, suggesting that the hypertrophic phenotype is modulated not by genetic etiologic factors alone. In contrast, prognosis reflected genotype; near normal life expectancy is found in hypertrophic cardiomyopathy caused by the alpha-tropomyosin mutation Asp175Asn.  相似文献   

8.
Veterinary ethics in the liberalized market: the Zambian environment   总被引:1,自引:0,他引:1  
BACKGROUND: This study was performed to assess the functional capacity of the survivors of septal myectomy for the treatment of hypertrophic obstructive cardiomyopathy in long-term follow-up as assessed by dobutamine stress echocardiography. METHODS: Sixty-nine patients with hypertrophic obstructive cardiomyopathy underwent septal myectomy between 1975 and 1996. The mean age was 25.4 +/- 13.6 years (range, 6-58 years), and 10 of the patients were women. The early mortality was 4.3%. Hospital survivors (95.7%) were followed up for a mean of 43.8 +/- 28.7 months (range, 6-114 months). RESULTS: The postoperative mean functional capacity of the group was 1.47 +/- 0.56. No late deaths were reported. Forty-nine patients (74.2%) were evaluated with standard echocardiographic techniques, and 29 (43.9%) patients underwent dobutamine stress echocardiography. There was a significant decrease in the thickness of the interventricular septum after surgery. The mean preoperative and postoperative septal thickness was 1.99 +/- 0.59 cm (range, 1.3-3.8 cm) and 1.55 +/- 0.41 cm (range, 0.96-2.8 cm), respectively (p < 0.004). The mean posterior wall thickness was significantly less than the preoperative value (p = 0.008) and the left ventricular end-diastolic diameter was slightly greater in the postoperative measurements, but the difference was not significant (p = 0.162). Postoperative left ventricular outflow systolic gradients were reduced significantly when compared with preoperative values (preoperative mean, 78.4 +/- 33.6 mm Hg, range, 50-212 mm Hg versus postoperative mean, 17.9 +/- 15.9 mm Hg: range, 0-40 mm Hg; p < 0.0001). CONCLUSION: Septal myectomy for patients with hypertrophic obstructive cardiomyopathy is a safe procedure with excellent clinical and functional results in the long-term follow-up.  相似文献   

9.
The aim of this study was to evaluate echographically anatomic and functional features of the left ventricle in adult patients with valvular aortic stenosis according to the presence or absence of congestive heart failure and the level of ventricular performance. Fifty-six adult patients with moderate-to-severe aortic stenosis underwent echocardiographic Doppler examination in order to evaluate left ventricular mass and dimensions, systolic function and filling dynamics. Twenty-seven patients had no heart failure and were symptomatic for angina (5), syncope (4) or were symptom-free (group I); the other 29 had heart failure (group II): 16 with normal left ventricular systolic performance (fractional shortening > 25%, group IIa) and 13 with systolic dysfunction (fractional shortening < or = 25%, group IIb). Despite a similar left ventricular mass, compared to group IIa, group IIb showed a significant left ventricular dilatation (end-diastolic diameter: 61 +/- 6.5 vs. 45.5 +/- 6.1 mm, p < 0.001) and mild or no increase in wall thickness (11.5 +/- 1.6 vs. 14.9 +/- 2 mm, p < 0.001). Indices of left ventricular filling on Doppler transmitral flow were also significantly different between the two groups, with a higher early-to-late filling ratio and a shorter deceleration time of early filling in group IIb (2.8 +/- 1.9 vs. 1.2 +/- 0.85, p < 0.01, and 122 +/- 66 vs. 190 +/- 87 ms, p < 0.05, respectively), both indirectly indicating higher left atrial pressure. Finally, heart failure was generally more severe in group IIb patients. In some patients with aortic stenosis, symptoms of heart failure may be present despite a normal left ventricular systolic function and seem to depend on abnormalities of diastolic function. The presence of systolic or isolated diastolic dysfunction appears to be related to a different geometric adaptation of the left ventricle to chronic pressure overload.  相似文献   

10.
OBJECTIVES: This study aimed to assess autonomic nervous system activity in patients with hypertrophic cardiomyopathy. BACKGROUND: Patients with hypertrophic cardiomyopathy are traditionally thought to have increased sympathetic activity. However, convincing evidence is lacking. METHODS: Heart rate variability was assessed from 24-h ambulatory electrocardiographic (Holter) recordings in 31 patients with hypertrophic cardiomyopathy and 31 age- and gender-matched normal control subjects in a drug-free state. Spectral heart rate variability was calculated as total (0.01 to 1.00 Hz), low (0.04 to 0.15 Hz) and high (0.15 to 0.40 Hz) frequency components using fast Fourier transformation analysis. RESULTS: There was a nonsignificant decrease in the total frequency component of heart rate variability in patients with hypertrophic cardiomyopathy compared with that of normal subjects (mean +/- SD 7.24 +/- 0.88 versus 7.59 +/- 0.57 ln[ms2], p = 0.072). Although there was no significant difference in the high frequency component (5.31 +/- 1.14 versus 5.40 +/- 0.91 ln[ms2], p = 0.730), the low frequency component was significantly lower in patients than in normal subjects (6.25 +/- 1.00 versus 6.72 +/- 0.61 ln[ms2], p = 0.026). After normalization (i.e., division by the total frequency component values), the low frequency component was significantly decreased (38 +/- 8% versus 43 +/- 8%, p = 0.018) and the high frequency component significantly increased (16 +/- 6% versus 12 +/- 6%, p = 0.030) in patients with hypertrophic cardiomyopathy. The low/high frequency component ratio was significantly lower in these patients (0.94 +/- 0.64 versus 1.33 +/- 0.55, p = 0.013). In patients with hypertrophic cardiomyopathy, heart rate variability was significantly related to left ventricular end-systolic dimension and left atrial dimension but not to maximal left ventricular wall thickness. No significant difference in heart rate variability was found between 14 victims of sudden cardiac death and 10 age- and gender-matched low risk patients. CONCLUSIONS: Our observations suggest that during normal daily activities, patients with hypertrophic cardiomyopathy experience a significant autonomic alteration with decreased sympathetic tone.  相似文献   

11.
TDI is a new echocardiographic technique that calculates and displays color-coded myocardial velocity on-line. To determine the feasibility of endocardial velocity throughout the cardiac cycle as a means to quantify regional function, 20 normal subjects aged 30 +/- 5 years and 12 patients with heart disease aged 62 +/- 17 years were studied with a prototype TDI system. TDI M-mode images were acquired by using a multicolored velocity map (display range, -30 to 30 mm/sec; temporal resolution, 90 Hz). Color-coded velocity data were then converted to numeric values off-line at 50 msec intervals. Posterior wall velocities throughout the cardiac cycle by TDI were closely correlated with velocity calculations from the first derivative of routine digitized M-mode tracings (group mean r = 0.88 +/- 0.03, SEE = 7.0 +/- 1.1 mm/sec). Anteroseptal TDI color-coded systolic velocity occurred 164 +/- 84 msec from the onset of the electrocardiographic QRS compared with 203 +/- 33 msec in the posterior wall (P < 0.05) in normal subjects, consistent with normal electrical activation. Significant differences in systolic and diastolic posterior wall TDI velocity data were observed in patients with hypokinetic or akinetic segments assessed by independent routine study when compared with normal controls. Calculated systolic and early diastolic posterior wall TDI indexes correlated significantly with percentage of wall thickening. Of abnormal anteroseptal segments, TDI systolic time velocity integrals were significantly different than normal and correlated with percentage of wall thickening. TDI has potential to quantitatively assess regional left ventricular function.  相似文献   

12.
Velocity-encoded cine MRI (VEC-MRI) can measure volume flow at specified site in the heart. This study used VEC-MRI to measure flow across the mitral valve to compare the contribution of atrial systole to left atrial filling in normal subjects and patients with left ventricular hypertrophy. The study population consisted of 12 normal subjects (mean age 34.5 years) and nine patients with various degrees of left ventricular hypertrophy resulting from aortic stenosis (mean age 70 years). VEC-MRI was performed in double-oblique planes through the heart to measure both the mitral inflow velocity pattern (E/A ratio) and the volumetric flow across the mitral valve. The left atrial contribution to left ventricular filling (AC%) was calculated. The results were compared with Doppler echocardiographic parameters. The VEC-MRI-derived mitral E/A ratios showed a significant linear correlation with E/A ratios calculated from Doppler echocardiography (r = 0.94), and the VEC-MRI-derived E/A ratios (2.1 +/- 0.5 vs 1.0 +/- 0.4) and AC% values (24.9 +/- 7.2 vs 45.7 +/- 16.4) were significantly different between normal subjects and patients with aortic stenosis (p < 0.01 in both groups). The same differences were seen in the Doppler echocardiographic parameters. The VEC-MRI-derived E/A ratio and AC% showed significant hyperbolic and linear correlations with left ventricular mass indexes (r = 0.95 and 0.86). In addition, the VEC-MRI-determined E/A ratio and the volumetric AC% displayed a highly significant hyperbolic correlation (r = 0.95). Thus VEC-MRI can be used to evaluate left ventricular diastolic filling characteristics in normal subjects and patients with abnormalities of diastolic filling.  相似文献   

13.
OBJECTIVES: We sought to identify the pattern of disturbed left ventricular physiology associated with symptom development in elderly patients with effort-induced breathlessness. BACKGROUND: Limitation of exercise tolerance by dyspnea is common in the elderly and has been ascribed to diastolic dysfunction when left ventricular cavity size and systolic function appear normal. METHODS: Dobutamine stress echocardiography was used in 30 patients (mean [+/-SD] age 70 +/- 12 years; 21 women, 9 men) with exertional dyspnea and negative exercise test results, and the values were compared with those in 15 control subjects. RESULTS: Before stress, left ventricular end-diastolic and end-systolic dimensions were reduced, fractional shortening was increased, and the basal septum was thickened (2.3 +/- 0.5 vs. 1.4 +/- 0.2 cm, p < 0.001, vs. control subjects) in the patients, but posterior wall thickness did not differ from that in control subjects. Left ventricular outflow tract diameter, measured as systolic mitral leaflet septal distance, was significantly reduced (13 +/- 4.5 vs. 18 +/- 2 mm, p < 0.001). Isovolumetric relaxation time was prolonged, and peak left ventricular minor axis lengthening rate was reduced (8.1 +/- 3.5 vs. 10.4 +/- 2.6 cm/s, p < 0.05), suggesting diastolic dysfunction. Transmitral velocities and the E/A ratio did not differ significantly. At peak stress, heart rate increased from 66 +/- 8 to 115 +/- 20 beats/min in the control subjects, but blood pressure did not change. Transmitral A wave velocity increased, but the E/A ratio did not change. Left ventricular outflow tract velocity increased from 0.8 +/- 0.1 to 2.0 +/- 0.2 m/s, and mitral leaflet septal distance decreased from 18 +/- 2 to 14 +/- 3 mm, p < 0.001. In the patients, heart rate rose from 80 +/- 12 to 132 +/- 26 beats/min and systolic blood pressure from 143 +/- 22 to 170 +/- 14 mm Hg (p < 0.001 for each), but left ventricular dimensions did not change. Peak left ventricular outflow tract velocity increased from 1.5 +/- 0.5 m/s (at rest) to 4.2 +/- 1.2 m/s; mitral leaflet septal distance fell from 13 +/- 4.5 to 2.2 +/- 1.9 mm (p < 0.001); and systolic anterior motion of mitral valve appeared in 24 patients (80%) but in none of the control subjects (p < 0.001). Measurements of diastolic function did not change. All patients developed dyspnea at peak stress, but none developed a new wall motion abnormality or mitral regurgitation. CONCLUSIONS: Although our patients fulfilled the criteria for "diastolic heart failure," diastolic dysfunction was not aggravated by pharmacologic stress. Instead, high velocities appeared in the left ventricular outflow tract and were associated with basal septal hypertrophy and systolic anterior motion of the mitral valve. Their appearance correlated closely with the development of symptoms, suggesting a potential causative link.  相似文献   

14.
Previous studies have shown regression of left ventricular hypertrophy after pharmacologic treatment of hypertensive patients; however, the impact of regression of left ventricular hypertrophy on systolic function and on left and right ventricular diastolic function remains controversial and is difficult to assess because previous studies have not included concurrently studied age-matched control groups. Left ventricular mass, systolic function, and left and right ventricular diastolic function were assessed in 27 hypertensive patients, aged 43 +/- 6 years, by echocardiographic and Doppler studies before and 1, 3, 5, and 7 months after treatment. Left ventricular mass and ventricular function were concurrently evaluated in 27 age-matched normotensive subjects. Treatment with antihypertensive agents resulted in a significant (p < 0.001) reduction in diastolic blood pressure of 15 mmHg, measured at 1 month and sustained throughout the study. In response to hemodynamic unloading, left ventricular mass index decreased from 129 +/- 30 gm/m2 at baseline to 105 +/- 26 (p < 0.05) and 88 +/- 14 gm/m2 (p < 0.05) at 1 and 3 months of treatment, respectively, and remained unchanged over the subsequent 4 months. After 3 months of treatment, left ventricular mass index was similar in treated hypertensive and control subjects. Systolic function, assessed in terms of the relationship between shortening fraction and end-systolic wall stress, was unchanged throughout the treatment period and was no different from that in control subjects. However, patients with an initially depressed shortening fraction experienced a greater increase in shortening fraction during treatment compared to those with an initially normal shortening fraction (11% +/- 4% vs 5% +/- 5%, p < 0.01) and showed an improvement in the relationship between shortening fraction and end-systolic wall stress during treatment. Ventricular filling dynamics improved during the first 3 months of treatment, after which they were unchanged. Ventricular filling dynamics were similar in treated hypertensive patients and control subjects. In conclusion, sustained hemodynamic unloading of the left ventricle results in normalization of left ventricular mass, systolic function, and left and right ventricular diastolic filling dynamics, compared to those in age-matched control subjects.  相似文献   

15.
OBJECTIVES: To assess the relation between white coat hypertension and alterations of left ventricular structure and function. DESIGN: Cross sectional survey. SETTING: Augsburg, Germany. SUBJECTS: 1677 subjects, aged 25 to 74 years, who participated in an echocardiographic substudy of the monitoring of trends and determinants in cardiovascular disease Augsburg study during 1994-5. OUTCOME MEASURES: Blood pressure measurements and M mode, two dimensional, and Doppler echocardiography. After at least 30 minutes' rest blood pressure was measured three times by a technician, and once by a physician after echocardiography. Subjects were classified as normotensive (technician <140/90 mm Hg, physician <160/95 mm Hg; n=849), white coat hypertensive (technician <140/90 mm Hg, physician >=160/95 mm Hg; n=160), mildly hypertensive (technician >=140/90 mm Hg, physician <160/95 mm Hg; n=129), and sustained hypertensive (taking antihypertensive drugs or blood pressure measured by a technician >=140/90 mm Hg, and physician >=160/95 mm Hg; n=538). RESULTS: White coat hypertension was more common in men than women (10.9% versus 8.2% respectively) and positively related to age and body mass index. After adjustment for these variables, white coat hypertension was associated with an increase in left ventricular mass and an increased prevalence of left ventricular hypertrophy (odds ratio 1.9, 95% confidence interval 1.2 to 3.2; P=0.009) compared with normotensive patients. The increase in left ventricular mass was secondary to significantly increased septal and posterior wall thicknesses whereas end diastolic diameters were similar in both groups with white coat hypertension or normotension. Additionally, the systolic white coat effect (difference between blood pressures recorded by a technician and physician) was associated with increased left ventricular mass and increased prevalence of left ventricular hypertrophy (P<0.05 each). Values for systolic left ventricular function (M mode fractional shortening) were above normal in subjects with white coat hypertension whereas diastolic filling and left atrial size were similar to those in normotension. CONCLUSION: About 10% of the general population show exaggerated inotropic and blood pressure responses when mildly stressed. This is associated with an increased risk of left ventricular hypertrophy.  相似文献   

16.
Quantitatively assessed ultrasonic backscatter is an index of ultrasonic tissue characterization directly related to morphometrically evaluated collagen in human beings. Our objective was to assess myocardial reflectivity pattern of patients with severe left ventricular hypertrophy caused by either aortic stenosis (AS) or aortic regurgitation (AR). Ten patients with AS, 10 patients with AR, and 10 closely age- and gender-matched healthy controls were studied by two-dimensional Doppler echocardiography. By using an echocardiographic prototype, we performed a radiofrequency analysis to obtain quantitative operator-independent measurements of the integrated backscatter signal of the ventricular septum and the posterior wall (integrated backscatter index: IBI, expressed in percentage). All patients with stenosis or aortic insufficiency showed a normal regional and global resting systolic function (fractional shortening: AS = 36.0 +/- 6.6 versus AR = 40.3 +/- 6.2 versus control = 40.2 +/- 8.7; p = not significant [NS]) Left ventricular mass index (Devereux's formula) was markedly increased in patients with stenosis or aortic insufficiency (AS = 199.3 +/- 18 versus AR = 208.8 +/- 60 versus control = 97.3 +/- 11 g/m2; p < 0.0001). Myocardial echo density was increased in patients with stenosis or aortic insufficiency in comparison with controls, both in the septum (IBI%: AR = 40.7 +/- 7.9 versus AS = 33.4 +/- 4.2 versus control = 23.0 +/- 6.2; p < 0.0001) and in the posterior wall (IBI%: AR = 27.1 +/- 4.3 versus AS = 23.0 +/- 2.6 versus control = 15.0 +/- 4.2; p < 0.0001). No significant correlations were found between septal and posterior wall IBI and their thickness. Abnormally increased myocardial echo density--possibly related to disproportionate collagen deposition--can be detected in patients with pressure or volume overload caused by aortic valve disease and without overt systolic dysfunction.  相似文献   

17.
To assess the usefulness of the tissue Doppler imaging variables for the evaluation of left ventricular (LV) systolic function, we compared variables obtained by the pulsed Doppler method with the LV ejection fraction (%EF) and the maximum value for the first derivative of LV pressure (peak dP/dt). We examined 65 patients, including 15 patients with noncardiac chest pain, 15 with ischemic heart disease, 15 with dilated cardiomyopathy, 10 with hypertensive heart disease, and 10 with asymmetric septal hypertrophic cardiomyopathy. The subendocardial systolic wall motion velocity patterns were recorded for LV posterior wall and ventricular septum in the parasternal LV long-axis view. The peak dP/dt was significantly lower in the hypertensive heart disease, hypertrophic cardiomyopathy, and dilated cardiomyopathy groups. The peak systolic velocity was lower and the time from the electrocardiographic Q wave to the peak of the systolic wave for the posterior wall was longer in the hypertensive heart disease (5.9 +/- 0.5 cm/sec and 215 +/- 21 msec, respectively), hypertrophic cardiomyopathy (6.2 +/- 0.9 cm/sec and 217 +/- 17 msec, respectively), and dilated cardiomyopathy (5.2 +/- 0.8 cm/sec and 235 +/- 26 msec, respectively) groups than in the noncardiac chest pain (7.7 +/- 0.9 cm/sec and 187 +/- 24 msec, respectively) and the ischemic heart disease (7.6 +/- 0.8 cm/sec and 184 +/- 22 msec, respectively) groups. In all groups, the peak systolic velocity and the time from the electrocardiographic Q wave to the peak of the systolic wave for the posterior wall correlated directly and inversely, respectively, with the %EF (r = 0.59, p < 0.0001; r = -0.59, p < 0.0001) and the peak dP/dt (r = 0.75, p < 0.0001; r = -0.68, p < 0.0001). Both tissue Doppler variables for the ventricular septum did not correlate with the %EF but roughly correlated with peak dP/dt. We conclude that the systolic LV wall motion velocity parameters obtained by pulsed tissue Doppler imaging may be useful for noninvasive evaluation of global LV systolic function in patients with no regional asynergy.  相似文献   

18.
Myocardial texture analysis of two-dimensional echocardiographic gray level distribution is abnormal in hypertensive patients with severe increase of left ventricular mass. The aim of this study was to investigate the behavior of this parameter in hypertensive patients with absent-to-moderate left ventricular hypertrophy, more representative of the overall hypertensive population. We compared male essential hypertensive patients, with absent or mild-to-moderate left ventricular hypertrophy, with normotensive sedentary healthy subjects as controls. The groups (n = 18 each) were age- (+/- 2 years) and sex-matched. All subjects performed ambulatory blood pressure measurements for the evaluation of 24 h mean systolic and diastolic blood pressure. Quantitative analysis of echocardiographic digitized imaging was performed through a calibrated 256 gray level digitization system to calculate midseptum and midposterior end-diastolic and end-systolic first and second order textural analysis. In particular were observed the mean gray level cyclic variations to deriving the cyclic variation index (CVI). The hypertensives showed a significantly lower CVI compared with controls both for septum (P < .001) and for posterior wall (P < .0001). No significant relationships were found between CVI and relative diastolic thickness both of septum and posterior wall. Conversely, a significant inverse relationship was found between systolic arterial pressure values and CVI both of septum and posterior wall. Abnormalities of two dimensional echocardiographic gray level distribution are present also in hypertensive patients with absent or with mild-to-moderate levels of left ventricular hypertrophy, but seem unrelated to the degree of echocardiographic hypertrophy as such. Changes in collagen network distribution or microcirculatory alterations, secondary to pressure-volume overload per se or to other complex humoral factors, could explain these abnormalities. Further work is needed to establish the clinical, therapeutic, and prognostic implications of these findings.  相似文献   

19.
STUDY OBJECTIVES: Pulmonary hypertension is the most important complication in patients with atrial septal defect (ASD), but its role in limiting exercise has not been examined. This study sought to evaluate exercise performance in adults with ASD and determine the contribution of elevated pulmonary artery pressure in limiting exercise capacity. DESIGN: We used Doppler echocardiography during exercise in 10 adults (aged 34 to 70 years) with isolated ASD (New York Heart Association class I, II) and an equal number of matched control subjects. Incremental exercise was performed on an electrically braked upright cycle ergometer. Expired gases and VE were measured breath-by-breath. Two-dimensional and Doppler echocardiographic images were obtained at rest prior to exercise to determine ASD size, stroke volume (SV), shunt ratio (Qp:Qs), right ventricular outflow tract (RVOT) size, and right ventricular systolic pressure at rest (RVSPr). Doppler echocardiography was repeated at peak exercise to measure right ventricular systolic pressure during exercise (RVSPex). RESULTS: Resting echocardiography revealed that RVOT was larger (21+/-4 vs 35+/-8 mm, mean+/-SD; p=0.0009) and RVSPr tended to be higher (17+/-8 vs 31+/-8 mm Hg; p=0.08) in ASD; however, left ventricular SV was not different (64+/-23 vs 58+/-23 mL; p>0.05), compared with control subjects. Despite normal resting left ventricular function, ASD patients had a significant reduction in maximum oxygen uptake (VO2max) (22.9+/-5.4 vs 17.3+/-4.2 mL/kg/min; p=0.005). RVSPex was higher (19+/-8 vs 51+/-10 mm Hg; p=0.001) and the mean RVSP-VO2 slope (1+/-2 vs 18+/-3 mm Hg/L/min; p=0.003) and intercept (17+/-4 vs 27+/-4 mm Hg; p=0.05) were higher in the ASD group. VO2max correlated inversely with both RVSPr (r=-0.69; p=0.007) and RVSPex (r=-0.67; p=0.01). CONCLUSION: These findings suggest that adults with ASD have reduced exercise performance, which may be associated with an abnormal increase in pulmonary artery pressure during exercise.  相似文献   

20.
BACKGROUND: Ethanol causes vasodilation, which might have an adverse effect, due to increased obstruction of the left ventricular outflow tract, in patients with hypertrophic obstructive cardiomyopathy. We assessed the hemodynamic effects of the ingestion of ethanol, in an amount commonly consumed socially, in patients with hypertrophic cardiomyopathy. METHODS: We performed echocardiography in 36 patients before and several times after the ingestion of either 50 ml of 40 percent ethanol or an isocaloric placebo with the aroma of rum. Each patient received both ethanol and placebo, on different days. The patients, but not the physicians, were blinded to the content of the drink. We measured the sizes of the left atrium and left ventricle, the left-ventricular-wall thickness, blood pressure, heart rate, the degree of systolic anterior motion of the mitral valve, and the pressure gradient across the left ventricular outflow tract. RESULTS: The ingestion of ethanol regulated in a significant drop in the mean (+/- SD) systolic blood pressure (from 130.5 +/- 18.6 to 122.5 +/- 20.3 mm Hg, P<0.001), a significant increase in systolic anterior motion of the mitral valve (from a grade of 2.1 to a grade of 2.5, P<0.001), and a 63 percent increase in the mean gradient across the left ventricular outflow tract (from 38.1 +/- 26.5 to 62.2 +/- 42.4 mm Hg, P<0.001). These changes, which were not associated with symptoms, did not occur after the ingestion of placebo. CONCLUSION: The ingestion of a small amount of ethanol caused an increase in the gradient across the left ventricular outflow tract in patients with hypertrophic obstructive cardiomyopathy, which could have and adverse clinical effect.  相似文献   

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