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1.
Left ventricular size, mass and function in relation to the duration and quantity of heavy drinking in alcoholics. 总被引:3,自引:1,他引:2
Left ventricular (LV) hypertrophy and mild dysfunction are frequently observed in alcoholics but little is known about how they relate to the duration and severity of alcohol abuse. LV size, mass and function were studied using echocardiography and systolic time intervals in 78 middle-aged male alcoholics who also gave detailed accounts of the duration of heavy drinking, the quantity of recent ethanol consumption and the duration of abstinence. Compared with 34 healthy nonalcoholics, alcoholics had a higher LV mass index (85 +/- 2 [mean +/- standard error] vs 77 +/- 2 g/m2, p = 0.001), a thicker posterior wall (11 +/- 0.2 vs 10 +/- 0.2 mm, p = 0.02), a longer end-systolic diameter index (18 +/- 0.3 vs 17 +/- 0.3 mm/m2, p = 0.02), and a higher preejection period/ejection time ratio (0.36 +/- 0.01 vs 0.33 +/- 0.01, p = 0.002). In multivariate linear regression models, these abnormalities proved independent of the drinking history, except that posterior wall thickness was weakly related to the duration of heavy drinking (standardized correlation coefficient 0.36, p = 0.01). Univariate analyses suggested that the LV mass index and systolic time interval ratio had, if anything, a curvilinear relation to the total duration of heavy alcohol consumption. It is concluded that the LV hypertrophy and dysfunction found in alcoholics are poorly related to the duration and severity of self-reported alcohol abuse. Together with other data, this suggests that there is no simple linear dose-injury relation in the long-term cardiotoxicity of ethanol. Factors modifying the myocardial effects of ethanol need to be studies more in the future. 相似文献
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Left ventricular function of a sample of subjects with chronic alcohol intake, in the form of wine, and without clinical or electrocardiographic signs of heart disease was compared with that of a sample of normal control subjects using non-invasive polygraphic recordings. The statistical analysis has shown significant prolongation of PEP, PEPI, an increase in PEP/LVET, and a shortening of LVET and LVETI in the alcoholic subjects compared with the controls. All these abnormalities may be ascribed to left ventricular malfunction. 相似文献
4.
Systolic left ventricular dysfunction is relatively common in even asymptomatic alcoholics, but whether diastolic function is also altered is much less well-studied. We used M-mode and Doppler echocardiography to study left ventricular size, mass, systolic function and diastolic filling in 32 alcoholics free of clinically detectable heart disease and in 15 healthy control subjects. Left ventricular mass index and posterior wall thickness were higher in alcoholics than in controls, but there was no statistically significant difference either in end-diastolic size or in systolic ventricular function. More abnormalities were found in the Doppler indexes of diastolic function, however. The alcoholics had a prolonged relaxation time (200 +/- 6 vs 184 +/- 5 ms [mean +/- standard error], p less than 0.05), a decreased peak early diastolic velocity (52 +/- 2 vs 60 +/- 3 cm/s, p less than 0.05), a slower acceleration of the early flow (410 +/- 18 vs 552 +/- 43 cm/s2, p less than 0.01), and a higher atrial-to-early peak velocity ratio (0.74 +/- 0.04 vs 0.60 +/- 0.05, p less than 0.05). This pattern of changes suggests a primary abnormality in the relaxation of the left ventricle. In multivariate analyses, the abnormalities in the Doppler indexes were independent of the duration of alcoholism, the quantity of the most recent ethanol exposure and the increased mass of the left ventricle. Impaired early filling of the left ventricle due to delayed relaxation is common in asymptomatic alcoholics and may in fact be the earliest functional sign of preclinical alcoholic cardiomyopathy. 相似文献
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Improvement of left ventricular function in chronic alcoholics following abstinence from ethanol 总被引:2,自引:0,他引:2
Preclinical abnormalities of left ventricular function are frequently found in chronic alcoholics. In 12 chronic alcoholics without cardiomyopathy and in 12 healthy controls, systolic time intervals and echocardiograms were investigated before and after 12 months of abstinence from alcohol. In chronic alcoholics, an increase was found in the PEP/LVET ratio (0.31 +/- 0.06; in controls 0.24 +/- 0.05; t = 3.11; p less than 0.005), the diastolic interventricular septal thickness (6.0 +/- 2.0 mm/m2; in controls 4.1 +/- 1.0; t = 2.95; p less than 0.01), the left ventricular wall thickness (6.3 +/- 1.0 mm/m2; in controls 4.9 +/- 1.0; t = 3.43; p less than 0.005) and the left ventricular diastolic dimension (29 +/- 4 mm/m2; in controls 26 +/- 3; t = 2.08; p less than 0.05). The left ventricular mass (135 +/- 33 g/m2; in controls 113 +/- 40; t = 1.47) did not differ from the controls. After 12 months of abstinence a significant decrease was found in the PEP/LVET ratio (0.26 +/- 0.05, i.e. -16%; t = 3.59; p less than 0.005), the diastolic interventricular septal thickness (4.7 +/- 0.9 mm/m2, i.e. -22%; t = 2.73; p less than 0.02), the left ventricular posterior wall thickness (5.6 +/- 1.0 mm/m2, i.e. -11%; t = 4.08; p less than 0.001) and the left ventricular mass (109 +/- 24 g/m2, i.e. -21%; t = 6.53; p less than 0.001). The left ventricular diastolic dimension (27 +/- 2 mm/m2, i.e. -7%; t = 1.3) did not change. In conclusion, in chronic alcoholics, the abstinence from alcohol can be followed by an improvement of left ventricular function. 相似文献
7.
G Pomini R Gribaldo F Bellavere M Lupia F Sale A Rugna L Costa G Molfese 《Giornale italiano di cardiologia》1986,16(4):295-300
Prolonged QT interval and arrhythmias have been reported to occur in chronic alcoholics. To investigate the role of chronic alcohol consumption in the onset of arrhythmias and the development of the preclinical left ventricular dysfunction, in a group of 12 asymptomatic chronic alcoholics with no clinical evidence of heart disease, with histologically proven hepatic damage, after a week of abstinence from alcohol, the following investigations were performed: measurements of the corrected QT interval (QTc), 24-hours Holter monitoring, systolic time intervals, M-mode echocardiograms. The results were compared to those of 10 normal subjects. Our data suggested no difference in QTc interval between chronic alcoholics and normal persons. The distribution of arrhythmias was not statistically different in the two groups, particularly frequent and complicated arrhythmias occurred in only one subject in each group. Preejection period corrected for heart rate (PEPI) was significantly longer in alcoholics (132 +/- 16 vs 119 +/- 11, p less than 0.05). All echocardiographic parameters examined were not significantly different in the two groups. On the basis of our results, our impression is that the arrhythmogenic role of alcohol, not under acute ingestion, is relatively unimportant and further studies are needed to become a definitive conclusion about subclinical alcoholic cardiomyopathy. 相似文献
8.
R N Sachs J R Attali F Crépin D Palsky S Lancrenon P Tellier P Aeberhard G Bedig J Fermanian M Vulpillat 《La Revue de médecine interne / fondée ... par la Société nationale francaise de médecine interne》1985,6(1):68-76
49 diabetics (D) (26 IDD and 23 NIDD) were compared to 32 controls (C). Absence of ischemic cardiopathy (IC) was confirmed by routine investigations and noninvasive cardiovascular techniques, including an exercise ECG using 12 leads and a thallium 201 scintigraphy. Our results show: a) a prolonged mean isovolumetric relaxation time (IVRT) as studied by the M mode echocardiography and phonomechanography: D = 0,10 sec +/- 0,04; C = 0,05 sec +/- 0,02; p less than 0,0001; b) a reduced mean EF slope: D = 97,48 +/- 37,08 mm / sec; C = 125,68 +/- 34,35; p less than 0,005; c) a high mean Weissler index (ratio of PEP to LVET): D = 40 +/- 0,08; C = 33 +/- 0,05; p less than 0,01. IVRT and EF slope abnormalities are related to increased myocardial stiffness and impaired LV compliance. In the absence of changes in preload and afterload, the high Weissler index reflects impaired contractility of the myocardium. These abnormalities are related neither to the duration of diabetes nor to the presence or severity of the complications. With the M mode echocardiography, mean diastolic and systolic thickness of the septum is greater in D with retinopathy than in C (p less than 0,005 and p less than 0,03 respectively); mean diastolic and systolic thickness of the posterior wall is greater in NIDD than in C (p less than 0,001 and p less than 0,025). We conclude that there is evidence of left ventricular functional abnormalities specific to diabetes and unrelated to IC and hypertension. Our findings support the hypothesis that they may be due to metabolic disorders and/or myocardial microangiopathy. 相似文献
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Charles A. Boucher John B. Bingham Mary D. Osbakken Robert D. Okada H.William Strauss Peter C. Block Frederick H. Levine Harry R. Phillips Gerald M. Pohost 《The American journal of cardiology》1981,47(5):991-1004
The ability to predict early postoperative left ventricular size and function in patients with isolated aortic or mitral regurgitation was determined utilizing multigated blood pool imaging before and 2 to 4 weeks after valve replacement (aortic valve, 20 patients; mitral valve, 20 patients). Early postoperatively, ejection fraction decreased significantly (p <0.001) in both patient groups (from 0.55 ± 12 to 0.40 ± 0.14 [mean ± 1 standard deviation] in patients with aortic regurgitation and from 0.66 ± 0.09 to 0.48 ± 0.11 in patients with mitral regurgitation). The decrease in ejection fraction was associated with a large decrease in stroke volume with minimal or no change in end-systolic volume; it was unrelated to the preoperative ejection fraction. Early postoperative ejection fraction correlated best with preoperative end-systolic volume and was normal in 14 (67 percent) of 21 patients with a preoperative ejection fraction above 0.60; 4 (27 percent) of 15 patients with a preoperative ejection fraction of 0.50 to 0.60; and in 0 of 4 patients with a preoperative ejection fraction below 0.50 (p <0.05). In addition, a repeated scan in 16 patients late (1 to 2 years) after operation showed a further reduction in endsystolic volume in patients with aortic regurgitation with an increase in ejection fraction toward preoperative values. There was no significant change in patients with mitral regurgitation.End-diastolic volume decreased significantly (p <0.001) early postoperatively (from 162 ± 60 to 102 ± 41 ml/m2 in patients with aortic regurgitation and from 131 ± 40 to 78 ± 30 ml/m2 in patients with mitral regurgitation). This decrease was closely related to a decrease in stroke volume and was unrelated to preoperative ejection fraction. Early postoperative end-diastolic volume correlated best with the preoperative end-systolic volume. The major part of the reduction in end-diastolic volume occurred within 2 weeks of valve replacement.Removal of chronic left ventricular volume overload due to aortic or mitral regurgitation produces a decrease in ejection fraction and end-diastolic volume. The early reduction is in part a result of altered loading conditions and may not necessarily imply alterations in myocardial contractile function. The reduction in ejection fraction appears to persist in patients with mitral regurgitation. 相似文献
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Hirokazu Miyoshi Yoshifumi Oishi Yukio Mizuguchi Arata Iuchi Norio Nagase Nusrat Ara Takashi Oki 《Journal of the American Society of Hypertension》2013,7(3):206-215
Our aim was to investigate the relationships between left atrial (LA) structural and functional changes and left ventricular (LV) dysfunction related to LV pressure overload in asymptomatic patients with hypertension. One hundred and twenty-six asymptomatic patients with hypertension and LV ejection fraction (EF) ≥60% were studied. Conventional, pulsed and tissue Doppler, and two-dimensional speckle-tracking echocardiography (2DSTE) were performed to seek the independent determinants for alterations in LA structure and function. LA volume index (LAVI) correlated with age, body mass index (BMI), end-diastolic ventricular septal thickness (VSth), end-diastolic LV posterior wall thickness, relative LV wall thickness (RWT), LV mass index, peak A velocity of transmitral flow, E/e’, and peak systolic and early diastolic LA strains and strain rates. Peak LA strain during ventricular systole (S-LAs) correlated with age, BMI, heart rate (HR), end-systolic LV diameter, LAVI, VSth, RWT, LVEF, e’, E/e’, peak systolic LV radial strain, and peak early diastolic LV longitudinal strain rate. Multivariate regression analyses indicated that LV mass index, peak A velocity, E/e’, and S-LAs are defined as strong predictors related to LAVI, and that BMI, HR, LAVI, and peak systolic LV radial strain are defined as strong predictors related to S-LAs. In conclusion, 2DSTE demonstrated that alterations in LA structure and function are mainly associated with LV diastolic and systolic dysfunction, respectively, in preclinical patients with hypertension. 相似文献
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R I Hamby W J Noble D H Murphy I Hoffman 《Journal of the American College of Cardiology》1983,1(4):1011-1017
The atrial contribution to ventricular stroke volume was evaluated in 50 patients with coronary artery disease and found to be related to left ventricular function. All patients underwent complete hemodynamic and angiographic studies. Angiographic volume studies were utilized to determine atrial contribution to the stroke volume, end-systolic volume and ejection fraction. In 11 patients without heart disease, atrial contribution to stroke volume was (mean value +/- standard deviation) 9.3 +/- 6 ml/m2 compared with 13.5 +/- 6 ml/m2 in the patients with coronary disease (probability [p] less than 0.05). The percent of atrial contribution to stroke volume was 20 +/- 7 and 33 +/- 11%, respectively, in normal subjects and patients with coronary disease (p less than 0.05). The combination of congestive heart failure and cardiomegaly was the only clinical aspect associated with a significantly higher (p less than 0.05) atrial contribution to stroke volume than that in the remaining patients with coronary disease (46 versus 31%). Relating the atrial contribution to stroke volume to the left ventricular end-diastolic pressure, stroke volume, end-systolic volume and ejection fraction revealed correlation coefficients of 0.30, -0.44, 0.56 and -0.64, respectively. No patient with a normal ejection fraction (greater than 0.50) had an atrial contribution greater than 40% of stroke volume. The ratio of peak left ventricular systolic pressure/end-systolic volume (mm Hg/ml) was 2.7 +/- 1.5 in patients (n = 14) with an atrial contribution greater than 40% of stroke volume compared with 5.3 +/- 3.4 in patients having an atrial contribution of 40% or less (p less than 0.01). These findings indicate that atrial contribution to stroke volume is inversely related to left ventricular function. 相似文献
14.
Early changes in left ventricular subendocardial function after successful coronary angioplasty.
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M Y Henein K Priestley T Davarashvili N Buller D G Gibson 《Heart (British Cardiac Society)》1993,69(6):501-506
OBJECTIVE--To study the early effects of coronary angioplasty on resting left ventricular long axis function, reflecting that of the subendocardium. DESIGN--Prospective echocardiographic and Doppler examination of patients with coronary artery disease, before and after single vessel coronary angioplasty. SETTING--A tertiary referral centre for cardiac diseases with facilities for invasive and non-invasive investigation. PATIENTS--23 patients with significant left coronary disease being considered for coronary angioplasty. RESULTS--Before angioplasty the mean (SD) isovolumic relaxation time was longer than normal (75(19) ms v 55 (10), p < 0.001) with a significant increase in transverse dimension change before mitral valve opening, and peak rate of early diastolic thinning (8(3) v 10.4 (2.6) cm/s (p < 0.001)) was reduced. Long axis motion was frequently abnormal. The interval from the onset of the Q wave to the onset of shortening was prolonged (118 (30) ms v 90 (19) at the left site and 115 (26) ms v 81 (9) at the septal site, p < 0.001) and the onset of early diastolic rapid lengthening delayed with respect to the aortic valve closure sound (A2) by 85 (34) ms v 58 (11) at the left site and 88 (33) ms v 60 (9) at the septal site (p < 0.001). Although overall amplitude was reduced at the septal site only (1.23 (0.3) cm v 1.5 (0.4), p < 0.05), the extent (0.8 (0.2) cm v 1.04 (0.3) at the left site and 0.66 (0.2) cm v 0.9 (0.3) at the septal site, p < 0.001) and peak rate (6.2 (2) cm/s v 10 (2.5) at the left site and 5.4 (2.3) cm/s v 8.5 (2) at the septal site, p < 001) of early diastolic lengthening were both much lower than normal. The E/A ratio on transmitral Doppler was modestly reduced (1.0 (0.7) v 1.4 (0.4), p < 0.05). After angioplasty: isovolumic relaxation time shortened to 64 (18) ms (p < 0.001) and left ventricular incoordination regressed. Long axis shortening with respect to Q (98 (32) ms v 118 (30) at the left site and 94 (23) ms v 115 (26) at the septal site, p < 0.01) and that of lengthening with respect to A2 both normalised. Early diastolic peak lengthening rate increased (7.5 (2.1) cm/s v 6.2 (2) at the left site, and 6.3 (2.4) cm/s v 5.4 (2.3) at the septal site, p < 0.001). The early diastolic peak thinning rate of the posterior wall significantly increased (10 (3.5) cm/s v 8 (3), p < 0.005) as did mitral E/A ratio 1.2 (0.7) v 1.0 (0.7), p < 0.05). CONCLUSION--Long axis motion, representing the function of longitudinally arranged subendocardial fibres, is consistently abnormal in the resting state in coronary artery disease. These systolic and diastolic abnormalities return towards normal after successful angioplasty, suggesting that they are the direct effect of coronary artery stenosis. 相似文献
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A Nagata T Homma K Ueno K Shimakura H Oguchi Y Tamura H Hirabayashi S Kawa S Furuta 《Gastroenterologia Japonica》1985,20(2):125-130
In order to elucidate the functional states of the pancreas in the asymptomatic latent stage of chronic alcoholic pancreatitis, 45 chronic alcoholics with no obvious pancreatic structural abnormalities judged by endoscopic pancreatography were studied by pancreozymin-secretin test. We found three patterns of exocrine pancreatic function in alcoholics with or without cirrhosis: normal secretion (40%), hyposecretion (29%) and hypersecretion (31%). In the hyposecretory group, the amylase output proved to be impaired more frequently. In the hypersecretory group increases were observed in one or more of the following parameters, volume, bicarbonate output and amylase output. However, increase in volume was a fundamental condition in this hypersecretion. This study confirmed that exocrine pancreatic hyposecretion and hypersecretion were almost equally frequent in asymptomatic chronic alcoholics with no obvious pancreatographic abnormalities. These results suggest that ongoing exocrine pancreatic dysfunctions exist in the subclinical stage of chronic alcoholic pancreatitis. 相似文献
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Early improvement in left ventricular diastolic function after relief of chronic right ventricular pressure overload 总被引:1,自引:0,他引:1
Chronic right ventricular pressure overload is associated with left ventricular diastolic dysfunction. Whether or not an abrupt reduction in pulmonary artery pressure in patients with chronic pulmonary hypertension results in early improvement of left ventricular diastolic function is unknown. To assess this, the Doppler indexes of left ventricular diastolic function and echocardiographic measures of left ventricular volume were analyzed in 22 patients (age, 41 +/- 14 years, mean +/- SD) before and within 1 week after pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension. Mean duration of cardiopulmonary symptoms was 37 months (range, 4 months to 9 years). After operation, mean pulmonary artery pressure and pulmonary vascular resistance decreased (50 +/- 13 to 29 +/- 9 mm Hg and 904 +/- 654 to 283 +/- 243 dynes.sec/cm5, respectively, both p less than 0.001), pulmonary artery wedge pressure was unchanged (11 +/- 5 to 12 +/- 5 mm Hg), and cardiac index increased (2.0 +/- 0.5 to 2.8 +/- 0.7 l/min/m2 p less than 0.001). Left ventricular end-diastolic volume and stroke volume increased significantly (58.5 +/- 18.0 to 76.6 +/- 25.0 ml and 30.3 +/- 12.3 to 41.8 +/- 12.5 ml, respectively, both p less than 0.001) after surgery.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
17.
Soo-Myoung Shin Wan-Joo Shim 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2014,36(7):517-523
The number of young adults with hypertension (HT) is increasing. We investigated the changes of left ventricular (LV) function and their relationship to the ambulatory blood pressure monitoring (ABPM) parameters in young adults with never-treated HT and no LV hypertrophy.Consecutive young patients (29.5?±?5.9 years) with first diagnosed primary HT and sex- and age-matched normotensive controls were enrolled. We excluded patients who had LV hypertrophy. ABPM was performed in all HT patients. LV strain values were obtained by two-dimensional speckle tracking imaging.There was no difference in LV ejection fraction and mass index between HT patients (n?=?40) and controls (n?=?40). LV global longitudinal strain (GLS) was lower (p?=?0.001) and twist was higher (p?=?0.002) in HT patients than in controls. LV GLS was significantly correlated to averaged and daytime diastolic BP and its variability and most related to daytime diastolic BP (β?=?0.33, p?=?0.03). Patients with high daytime diastolic BP and its variability showed lower GLS (both p?=?0.02) and higher twist (both p?=?0.04) than patients with low daytime diastolic BP.Early changes of LV function with decreased GLS and increased twist were shown in young HT patients even with no LV hypertrophy and daytime diastolic BP and its variability were related to the impairment of LV function. 相似文献
18.
Age-associated changes in left ventricular diastolic function are related to increasing left ventricular mass 总被引:5,自引:0,他引:5
Isometric exercise (IME) produces significant hemodynamic changes in the cardiovascular system. We have used IME to study the effect of age on diastolic left ventricular (LV) function in 100 normal volunteers. The E/A ratio (peak velocity of early/atrial filling phases), deceleration time (DT), and isovolumic relaxation time (IVRT) of the transmitral flow were assessed during echocardiography with pulsed-Doppler ultrasound at rest and at peak IME using handgrip. LV mass index (LVMI) and LV ejection fraction (LVEF) were also calculated. Both E/A and IVRT reduced significantly with increasing age. The LVEF decreased (P <.0001), whereas LVMI increased (P <.05) with advancing age. The LVEF was inversely related to LVMI (P <.05). An inverse relationship was noted between E/A and LVMI (P <.01) during IME. The contribution of the atrial contraction to the total diastolic flow increased significantly with advancing age (P <.02) and increased from 0.29 +/- 0.04 at rest to 0.34 +/- 0.08 during IME (P <.0001). It is concluded that with progressing age, the left ventricle becomes stiffer resulting in a reduction in early filling and a compensatory increase in flow due to atrial contraction. A progressive increase in LVMI, which accompanies aging may contribute to stiffening of the left ventricle and deterioration in diastolic function of the left ventricle. This is exaggerated by IME. 相似文献
19.
Decreased cardiac parasympathetic activity in chronic heart failure and its relation to left ventricular function. 总被引:1,自引:0,他引:1
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J Nolan A D Flapan S Capewell T M MacDonald J M Neilson D J Ewing 《Heart (British Cardiac Society)》1992,67(6):482-485
BACKGROUND--Activation of the sympathetic nervous system has been extensively studied in patients with chronic heart failure, but the parasympathetic nervous system has received relatively little attention. The objective in this study was to investigate cardiac parasympathetic activity in chronic heart failure and to explore its relation to left ventricular function. METHODS--Heart rate variability was measured from 24 hour ambulatory electrocardiograms by counting the number of times each RR interval exceeded the preceding RR interval by more than 50 ms (counts). This method provided a sensitive index of cardiac parasympathetic activity. RESULTS--Mean (range) of counts were: waking 48 (1-275)/h, sleeping 62 (0-360)/h, and total 1310 (31-7278)/24 h. These were lower than expected, and in 26 (60%) of the 43 patients counts fell below the lower 95% confidence intervals (95% CI) for RR counts in normal subjects. A significant correlation between total 24 hour RR counts and left ventricular ejection fraction was present (r = 0.49, p less than 0.05). CONCLUSIONS--These results indicate that most patients with chronic heart failure have reduced heart rate variability and therefore reduced cardiac parasympathetic activity. The degree of parasympathetic dysfunction is related to the severity of left ventricular dysfunction. This may be relevant to the high incidence of ventricular arrhythmias and poor prognosis of patients with chronic heart failure. 相似文献
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Decreased cardiac parasympathetic activity in chronic heart failure and its relation to left ventricular function. 总被引:6,自引:0,他引:6
J Nolan A D Flapan S Capewell T M MacDonald J M Neilson D J Ewing 《British heart journal》1992,67(6):482-485
BACKGROUND--Activation of the sympathetic nervous system has been extensively studied in patients with chronic heart failure, but the parasympathetic nervous system has received relatively little attention. The objective in this study was to investigate cardiac parasympathetic activity in chronic heart failure and to explore its relation to left ventricular function. METHODS--Heart rate variability was measured from 24 hour ambulatory electrocardiograms by counting the number of times each RR interval exceeded the preceding RR interval by more than 50 ms (counts). This method provided a sensitive index of cardiac parasympathetic activity. RESULTS--Mean (range) of counts were: waking 48 (1-275)/h, sleeping 62 (0-360)/h, and total 1310 (31-7278)/24 h. These were lower than expected, and in 26 (60%) of the 43 patients counts fell below the lower 95% confidence intervals (95% CI) for RR counts in normal subjects. A significant correlation between total 24 hour RR counts and left ventricular ejection fraction was present (r = 0.49, p less than 0.05). CONCLUSIONS--These results indicate that most patients with chronic heart failure have reduced heart rate variability and therefore reduced cardiac parasympathetic activity. The degree of parasympathetic dysfunction is related to the severity of left ventricular dysfunction. This may be relevant to the high incidence of ventricular arrhythmias and poor prognosis of patients with chronic heart failure. 相似文献