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1.
Diastolic dysfunction refers to abnormal diastolic filling properties of the left ventricle regardless of whether systolic function is normal or the patient has symptoms. Diastolic heart failure (HF), or more accurately, HF with preserved systolic function, is a distinct clinical entity characterized by the presence of the triad of impaired diastolic function, normal systolic function (left ventricular ejection fraction > 50%), and symptoms of HF. Patients with HF with preserved systolic function are frequently symptomatic from both acute and chronic elevations in left ventricular end-diastolic pressure and/or left atrial pressure.  相似文献   

2.
Heart failure (HF) has been classified as systolic and diastolic based on the left ventricular ejection fraction. We hypothesized that left ventricular diastolic dysfunction is an important element of HF regardless of ejection fraction. Two hundred six patients who had clinical HF were compared with 72 age-matched controls. Diastolic dysfunction, as assessed by the mitral filling pattern and tissue Doppler imaging, was present in >90% of patients who had HF regardless of ejection fraction and was more frequent and severe than in age-matched controls (p <0.001). In patients who had HF, B-type natriuretic peptide correlated with diastolic dysfunction (r = 0.62, p <0.001) but not with ejection fraction or end-diastolic volume index (EDVI). The degree of diastolic dysfunction influenced survival rate (risk ratio 1.64, p <0.05), whereas ejection fraction and EDVI did not. Systolic function measured by systolic mitral annular velocity was decreased in patients who had HF and an ejection fraction /=0.50 (6.6 +/- 1.8 cm/s) compared with control subjects (8.0 +/- 2.1 cm/s, p <0.01). Patients who had HF and an ejection fraction >/=0.50 had an increased ratio of ventricular mass to EDVI. Patients who had HF and an ejection fraction /=0.50 is associated with mild systolic dysfunction and an increased ratio of left ventricular mass to EDVI. In HF with an ejection fraction 相似文献   

3.
There are many myocardial and non-myocardial conditions that cause heart failure with normal left ventricular ejection fraction (LVEF). Among them, diastolic heart failure (heart failure due to diastolic dysfunction) is the most common cause of heart failure with normal LVEF. Diastolic heart failure easily can be diagnosed by comprehensive two-dimensional and Doppler echocardiography, which can demonstrate abnormal myocardial relaxation, decreased compliance, and increased filling pressure in the setting of normal LV dimensions and preserved LVEF. Therefore, diastolic heart failure should always be considered when LVEF is normal on two-dimensional echocardiography in patients with clinical evidence of heart failure. The diagnosis can be confirmed if Doppler echocardiography and myocardial tissue imaging provide evidence for impaired myocardial relaxation (i.e., decreased longitudinal velocity of the mitral annulus during early diastole and decreased propagation velocity mitral inflow), decreased compliance (shortened mitral A-wave duration and mitral deceleration time), and increased filling pressure (shortened isovolumic relaxation time and an increased ratio between early diastolic mitral and mitral annular velocities). Early identification of diastolic dysfunction in asymptomatic patients by the use of echocardiography may provide an opportunity to manage the underlying etiology to prevent progression to diastolic heart failure.  相似文献   

4.
There are many myocardial and non-myocardial conditions that cause heart failure with normal left ventricular ejection fraction (LVEF). Among them, diastolic heart failure (heart failure due to diastolic dysfunction) is the most common cause of heart failure with normal LVEF. Diastolic heart failure easily can be diagnosed by comprehensive two-dimensional and Doppler echocardiography, which can demonstrate abnormal myocardial relaxation, decreased compliance, and increased filling pressure in the setting of normal LV dimensions and preserved LVEF. Therefore, diastolic heart failure should always be considered when LVEF is normal on two-dimensional echocardiography in patients with clinical evidence of heart failure. The diagnosis can be confirmed if Doppler echocardiography and myocardial tissue imaging provide evidence for impaired myocardial relaxation (i.e., decreased longitudinal velocity of the mitral annulus during early diastole and decreased propagation velocity mitral inflow), decreased compliance (shortened mitral A-wave duration and mitral deceleration time), and increased filling pressure (shortened isovolumic relaxation time and an increased ratio between early diastolic mitral and mitral annular velocities). Early identification of diastolic dysfunction in asymptomatic patients by the use of echocardiography may provide an opportunity to manage the underlying etiology to prevent progression to diastolic heart failure.  相似文献   

5.
Background: Diastolic heart failure (DHF) is reported to account for 30–50% of heart failure presentations, but its prevalence in the absence of overt coronary disease is unclear. Diastolic heart failure is usually defined by exclusion (heart failure with normal left ventricular (LV) systolic function), and few studies have sought a specific diagnosis of diastolic dysfunction. The objective of the present study was to determine the prevalence of isolated DHF and characterise LV diastolic function in patients without clinical evidence of coronary disease, who were referred for LV function assessment.

Methods: Among 938 consecutive patients referred for assessment of LV function, diastolic dysfunction was sought in patients with clinical heart failure, normal systolic function, and no valvular or coronary disease. The evaluation was based on measurement of early (E) and late (A) transmitral velocities and E wave deceleration time (DT). Pulmonary vein systolic, diastolic and atrial reversal velocities were used to differentiate pseudonormal filling in patients with normal E/A and DT.

Results: Normal LV systolic function was present in 331 patients (35%), of whom 53 (6%) met criteria for a clinical diagnosis of DHF. Diastolic dysfunction was confirmed by echocardiography in 38 patients (72% of clinical DHF patients), of whom 27 had impaired LV relaxation, 10 had pseudonormal filling, and one had restrictive filling. Diastolic function was normal in 13 and indeterminate in two patients. Pseudonormal or restrictive LV filling were more prevalent in patients with acute heart failure (7/20, P < 0.05).

Conclusions: Carefully defined, isolated DHF is uncommon, but most of these patients demonstrate echocardiographic evidence of diastolic dysfunction.  相似文献   


6.
Heart failure (HF) has traditionally been divided into HF with a reduced ejection fraction (EF; systolic HF) and HF with a normal EF (diastolic HF). Both groups have reductions in exercise tolerance, neurohumoral activation, and abnormal left ventricular (LV) filling dynamics and impaired relaxation. Although the normal EF indicates that pump performance is adequately compensated, some of the patients with HF and a normal EF have reduced longitudinal systolic velocity indicating cardiac muscular contractile dysfunction. Regardless of EF, the severity of HF and its prognosis and degree of exercise intolerance are closely related to the degree of diastolic filling abnormalities. Patients with HF and a reduced EF have ventricular dilatation and elongated myocytes, whereas patients with HF and a normal EF do not. Thus, patients with HF have diastolic abnormalities regardless of EF and many patients with HF and a normal EF have contractile abnormalities despite preserved systolic pump performance. Heart failure with a normal EF and a reduced EF differs in the systolic LV pump performance and the type of remodeling. The mechanism of the differing remodeling responses is not known, but aging, sex differences, and diabetes may contribute.  相似文献   

7.
Exercise-induced impairment of left ventricular (LV) ejection fraction is common in patients with acromegaly and normal resting systolic function. This study aimed to clarify whether diastolic dysfunction plays a role in the abnormal adaptation to exercise in these patients. Forty-eight patients with active acromegaly underwent LV radionuclide angiography at rest and during exercise. Doppler echocardiography was also performed to assess LV mass index and diastolic function by combined analysis of mitral and pulmonary flow velocity curves. LV ejection fraction at peak exercise was related to rest ejection fraction (r = 0.78; P < 0.001), peak filling rate (r = 0.55; P < 0.01), LV mass index (r = -0.56; P < 0.001), and the difference between duration of diastolic reverse pulmonary vein flow and mitral flow at atrial contraction (Delta duration) (r = -0.54; P < 0.01). At stepwise regression analysis, rest ejection fraction and Delta duration were the only variables that independently influenced (P < 0.001) ejection fraction at peak exercise. Diastolic dysfunction is important in determining cardiac performance during exercise in patients with acromegaly and normal resting systolic function. Combined analysis of pulmonary vein and mitral flow velocity curves allows the identification of impaired LV diastolic function in such patients.  相似文献   

8.
To evaluate the prevalence of left ventricular (LV) diastolic dysfunction in patients with type 2 diabetes mellitus free of cardiovascular disease, we studied 86 normotensive men and women (mean age 46 +/- 6 years) with Doppler echocardiography. All subjects were asymptomatic for ischemic heart disease or heart failure. The traditional transmitral filling patterns were used to characterize diastolic physiology. The Valsalva maneuver was used to differentiate normal from pseudonormal LV filling pattern. All patients had a normal electrocardiogram at rest and a negative result on exercise echocardiography for inducible wall motion abnormalities. Global LV systolic function was normal (mean LV ejection fraction 58%, range 53% to 76%). Diastolic dysfunction was found in 41 subjects (47%) of which 26 (30%) had impaired relaxation and 15 (17%) had a pseudonormal filling pattern. The mean LV mass index was 101 g/m2 (range 86 to 122). All patients with a normal-filling physiology had gender-adjusted normal LV mass index (mean 93 +/- 11 g/m2), whereas 62% of those with either abnormal relaxation (mean 103 +/- 12 g/m2, p <0.001) or a pseudonormal pattern (mean 110 +/- 12 g/m2, p <0.001) had increased LV mass index. No subject in this cohort had restrictive diastolic physiology. In conclusion, diastolic dysfunction in type 2 diabetes mellitus patients is often found despite adequate metabolic control and freedom from clinically detectable heart disease. The Valsalva maneuver can unmask an additional 17% of patients with subclinical abnormal LV filling pattern, who otherwise would be classified as having a normal diastolic physiology. Increased LV mass index is closely associated with abnormal LV filling characteristics.  相似文献   

9.
The association of asymptomatic left ventricular (LV) diastolic dysfunction with cardiovascular outcomes in ambulatory patients with coronary heart disease (CHD) and no history of heart failure (HF) was examined. LV diastolic HF predicts adverse cardiovascular outcomes. However, the prevalence and prognosis of asymptomatic LV diastolic dysfunction in patients with established CHD in the absence of clinical HF is unknown. Six hundred ninety-three patients with stable CHD, normal systolic function (LV ejection fraction>or=50%), and no history of HF were evaluated. Echocardiography was used to classify LV diastolic function, and Cox proportional hazards models were used to evaluate the association of LV diastolic dysfunction with cardiovascular outcomes during 3 years of follow-up. Of 693 subjects with normal systolic function and no history of HF, 455 (66%) had normal LV diastolic function, 166 (24%) had mild LV diastolic dysfunction, and 72 (10%) had moderate to severe LV diastolic dysfunction. After multivariable adjustment, the presence of moderate to severe LV diastolic dysfunction was strongly predictive of incident hospitalization for HF (hazard ratio 6.3, 95% confidence interval 2.4 to 16.1, p=0.0003) and death from heart disease (HR 3.9, 95% confidence interval 1.0 to 14.8, p=0.05). In conclusion, moderate to severe LV diastolic dysfunction was present in 10% of patients with stable CHD with normal ejection fraction and no history of HF and predicts subsequent hospitalization for HF and death from heart disease. Patients with asymptomatic LV diastolic dysfunction may benefit from more aggressive therapy to prevent or delay the development of HF.  相似文献   

10.
The quantification of left ventricular (LV) volumes and assessment of their relation to systolic and diastolic dysfunction, infarct size and anatomic location were performed in 54 patients with a first acute myocardial infarction (AMI). Blood pool radionuclide angiography was used to assess LV end-diastolic, end-systolic, and stroke volume indexes, ejection fraction and peak diastolic filling rate. Infarct size was estimated from plasma MB creatine kinase activity. Substantial LV dilation occurred within the initial 24 hours of AMI. The peak diastolic filling rate was low, even in those patients with a normal ejection fraction. In comparison with inferior AMI (n = 25), patients with anterior AMI (n = 29) had a larger end-diastolic volume index (105 +/- 8 vs 81 +/- 4 ml/m2, p less than 0.01) and end-systolic volume index (64 +/- 7 vs 37 +/- 4 ml/m2, p less than 0.001), but similar stroke volume index (41 +/- 3 vs 43 +/- 2 ml/m2, difference not significant). No significant relation was noted between infarct size estimated by MB creatine kinase and any volumetric index. On repeat study (day 10 after AMI), end-diastolic and end-systolic volume indexes increased further (p less than 0.05 vs day 1) but ejection fraction and peak diastolic filling rate were unchanged. It was concluded that: (1) LV dilation occurs within hours of AMI in both inferior and anterior AMI, but is more marked in the latter; (2) significant LV diastolic dysfunction is the rule, even in patients with preserved LV systolic function; and (3) LV dilation is an early compensatory mechanism that maintains normal stroke volume, even in patients with severely reduced LV function.  相似文献   

11.
BACKGROUND: Based on the hypothesis that it reflects left ventricular (LV) diastolic pressures, B-type natriuretic peptide (BNP) is largely utilized as first-line diagnostic complement in the emergency diagnosis of congestive heart failure (HF). The incremental diagnostic value of tissue Doppler echocardiography, a reliable noninvasive estimate of LV filling pressures, has been reported in patients with preserved LV ejection fraction and discrepancy between BNP levels and the clinical judgment, however, its clinical validity in such patients in the presence of BNP concentrations in the midrange, which may reflect intermediate, nondiagnostic levels of LV filling pressures, is unknown. METHODS: 34 patients without history of HF, presenting with acute dyspnea at rest, BNP levels of 100-400 pg/ml and normal LV ejection fraction were prospectively enrolled (17 with congestive HF and 17 with noncardiac cause). Tissue Doppler echocardiography was performed within 3 hours after admission. RESULTS: Unlike BNP (P = 0.78), Boston criteria (P = 0.0129), radiographic pulmonary edema (P = 0.0036) and average E/Ea ratio (P = 0.0032) were predictive of congestive HF by logistic regression analysis. In this clinical setting, radiographic pulmonary edema had a positive predictive value of 80% in the diagnosis of congestive HF. In patients without evidence of radiographic pulmonary edema, average E/Ea > 10 was a powerful predictor of congestive HF (area under the ROC curve of 0.886, P < 0.001, sensitivity 100% and specificity 78.6%). CONCLUSION: By better reflecting LV filling pressures, bedside tissue Doppler echocardiography accurately differentiates congestive HF from noncardiac cause in dyspneic patients with intermediate, nondiagnostic BNP levels and normal LV ejection fraction.  相似文献   

12.
B-type natriuretic peptide (BNP) levels increase in systolic heart failure (HF). However, the value of BNP in hypertensive patients with suspected diastolic HF (symptoms suggestive of HF but normal ejection fraction) and its relation to myocardial function in these patients is unclear. We prospectively studied 72 ambulatory hypertensive subjects (40 women, mean age 58 ± 8 years) with exertional dyspnea and ejection fraction ≥50%. Diastolic function was evaluated with transmitral and pulmonary venous Doppler, mitral annular velocities (pulsed-wave tissue Doppler), and flow propagation velocity (color M-mode). Systolic function was assessed with strain and strain rate derived from color tissue Doppler imaging. BNP was related to myocardial function and the presence or absence of global diastolic dysfunction. By conventional Doppler criteria, 34 patients had normal left ventricular diastolic function and 38 had isolated diastolic dysfunction. BNP values were higher in patients with diastolic dysfunction (46 ± 48 vs 20 ± 20 pg/ml, P = 0.004) and were related independently to blood pressure, systolic strain rate, left atrial function (p <0.01 for all), and age (p = 0.015). Patients with diastolic dysfunction and pseudonormal filling had higher BNP levels compared with impaired relaxation (89 ± 47 vs 35 ± 42 pg/ml, P = 0.001). However, 79% of patients with diastolic dysfunction had BNP levels within the normal range. We conclude that in ambulatory hypertensive patients with symptoms suggestive of mild HF and normal ejection fraction, BNP is related to atrial and ventricular systolic parameters, blood pressure, and age. Although elevated in the presence of diastolic dysfunction, the BNP level mostly is in the normal range and, therefore, has limited diagnostic value in stable patients with suspected diastolic HF.  相似文献   

13.
Diastolic dysfunction plays an important role in the pathophysiology of heart failure. Although it is still controversial whether or not patients with preserved ejection fraction have depressed left ventricular (LV) systolic function, LV filling pressures determine exercise tolerance independent of the severity of systolic dysfunction. Therefore, estimation of LV filling pressures is important not only for diagnosis, but also for management of patients with heart failure. The efficacy and limitations of different diagnostic approaches, including Doppler imaging, are discussed.  相似文献   

14.
Nearly half of patients with heart failure (HF) have a normal ejection fraction (EF) and have been labeled as having diastolic HF. Diastolic HF is characterized by a normal EF, a variable amount of concentric left ventricular hypertrophy, and abnormal diastolic function. Differentiating diastolic HF from HF with a reduced EF (systolic HF) is important because these two forms of HF have different pathophysiology and thus might require different therapeutic approaches. Nevertheless, patients with diastolic HF and those with systolic HF have similar clinical symptoms and signs. Thus, clinical history and physical examination do not differentiate between diastolic and systolic HF. There is accumulating evidence that diastolic dysfunction is related to the severity of HF and prognosis regardless of EF. Thus, it is important to evaluate both systolic and diastolic function not only to differentiate between diastolic and systolic HF but also to identify high-risk patients.  相似文献   

15.
In secondary hypertrophy from chronic pressure or volume overload, or both, systolic as well as diastolic abnormalities of left ventricular (LV) function have been described, but their relation has not been defined. In 58 patients with aortic valve disease (28 with aortic valve stenosis, and 30 with aortic regurgitation) and in 11 control subjects, LV biplane cineangiography was performed simultaneously with LV high-fidelity pressure measurements. LV ejection performance was assessed by ejection fraction, and diastolic function by the time constant of LV pressure decay, the early and late peak filling rates, and the constants of chamber (pressure-volume relation) and myocardial stiffness (stress-strain relation). In the entire cohort (n = 69), ejection fraction was inversely related to the time constant of LV relaxation (r = -0.58, p less than 0.001) and to the constant of myocardial stiffness (r = -0.62, p less than 0.001). Despite preserved systolic contractile function (as evaluated from the ejection fraction-mean systolic stress relation), abnormalities in LV diastolic function were present in 9 of 18 patients with pressure overload and 20 of 22 with volume overload. None of the 58 patients with aortic valve disease had a reduced early peak filling rate, whereas a reduction in late peak filling rate was observed in 3 with aortic stenosis, but in none with aortic regurgitation. This, it appears that abnormalities of relaxation and passive diastolic myocardial stiffness precede alterations in myocardial contractility. Assessment of peak filling rates is not helpful to detect diastolic dysfunction in patients with aortic valve disease.  相似文献   

16.
Abnormalities of left ventricular (LV) filling may occur prior to systolic dysfunction in patients with both coronary and noncoronary heart disease. To determine the incidence of diastolic dysfunction and to assess the relationship of such dysfunction to systolic performance, we measured systolic and diastolic function at rest in a series of healthy volunteers (n = 10) and in patients with cardiovascular disease (n = 42). Twenty patients had coronary artery disease (CAD) with prior myocardial infarction, six patients had CAD without myocardial infarction, and the remaining 16 patients had a variety of noncoronary heart diseases, including valvular heart disease, dilated cardiomyopathy, and hypertensive disease. The 42 patients manifested a wide variation in LV systolic function (ejection fractions ranged from 6% to 65%). Patients with reduced LV ejection fraction (EF) manifested a reduction in cardiac output and peak ejection rate proportionate to the reduction in EF. Diastolic function showed a fall in LV peak (PFR) and average (AFR) filling rates; these were reduced in proportion to the fall in EF. Heart rate was an insensitive index of the magnitude of impairment of LV systolic function. These data suggest that measurements of diastolic function do not provide additional information in patients with impaired systolic function.  相似文献   

17.
Background: Sickle cell disease (SCD) is a hemoglobinopathy that affects one in 500 African Americans. Although it is well established that patients with SCD have left ventricular (LV) diastolic dysfunction, it is not clear whether they have subtle LV systolic dysfunction despite preserved ejection fraction (EF). We used three-dimensional speckle tracking echocardiography (3DSTE) to assess changes in both systolic and diastolic LV function in SCD. Methods: Transthoracic real time 3D images were obtained (Philips iE33) in 56 subjects, including 28 stable outpatients with SCD (age 33 ± 7 years) and 28 normal controls (age 35 ± 9 years). 3DSTE was performed using prototype software (4DLV Analysis, TomTec) to obtain LV volume and deformation time curves, from which indices of systolic and diastolic LV function were calculated. Results: In SCD patients, 3DSTE-derived LV filling parameters were significantly different from normal controls, reflecting an increase in both rapid and atrial filling volumes and prolonged active relaxation, depicted by a decrease in filling volume fractions at fixed times and an increase in rapid filling duration. Global LV systolic function was not only preserved but increased compared to controls, as reflected by significantly increased global longitudinal strain. Importantly, twist angle and torsion as well as radial and circumferential components of 3D strain were similar in both groups. Conclusions: 3DSTE was able to confirm diastolic dysfunction, as expected in some patients with SCD. However, 3DSTE strain analysis did not reveal any changes in LV systolic function. These findings provide novel insight into the pathophysiology of the cardiovascular complications of SCD.  相似文献   

18.
Left ventricular (LV) diastolic filling is abnormal at rest in many patients with coronary artery disease (CAD), even in the presence of normal resting LV systolic function. To determine the effects of improved myocardial perfusion on impaired. LV diastolic filling, we studied 25 patients with one-vessel CAD by high-temporal-resolution radionuclide angiography before and after percutaneous transluminal coronary angioplasty (PTCA). No patient had ECG evidence of previous myocardial infarction. Despite normal regional and global LV systolic function at rest in all patents, LV diastolic filling was abnormal (peak LV filling rate [PFR] less than 2.5 end-diastolic volumes (EDV)/sec or time to PFR greater than 180 msec) in 17 of 25 patients. Twenty-three patients had abnormal LV systolic function during exercise. After successful PTCA, LV ejection fraction and heart rate at rest were unchanged, but LV ejection fraction during exercise increased, from 52 +/- 8% (+/- SD) to 63 +/- 5% (p less than 0.001). LV diastolic filling at rest improved: PFR increased from 2.3 +/- 0.6 to 2.8 +/- 0.5 EDV/sec (p less than 0.001) and time to PFR decreased from 181 +/- 22 to 160 +/- 18 msec (p less than 0.001). Thus, a reduction in exercise-induced LV systolic dysfunction after PTCA, reflecting a reduction in reversible ischemia, was associated with improved LV diastolic filling at rest. These data suggest that in many CAD patients with normal resting LV systolic function and without previous infarction, abnormalities of resting LV diastolic filling are not fixed, but appear to be reversible manifestations of impaired coronary flow.  相似文献   

19.
To define the prevalence and role of left ventricular (LV) systolic dysfunction, LV diastolic dysfunction and mitral regurgitation (MR) in patients with acute pulmonary edema, 40 patients with coronary artery disease and acute pulmonary edema were prospectively evaluated within 36 hours of presentation. LV ejection fraction and 3 parameters of LV diastolic function were measured with radionuclide ventriculography, whereas MR was assessed with Doppler echocardiography. LV ejection fraction was normal in 11 (27%) and depressed in 29 (73%) patients. Moderate or severe MR without LV diastolic dysfunction was common and equally prevalent in patients with and without LV systolic dysfunction (33 vs 38%; difference not significant). Diastolic dysfunction without MR was less frequent but equally prevalent in patients with and without systolic dysfunction (17 vs 27%; difference not significant). Two (18%) of 11 patients without and 12 (33%) of 36 patients with LV systolic dysfunction had both MR and LV diastolic dysfunction. Furthermore, MR was clinically silent and unsuspected in two-thirds of all patients with MR, regardless of a normal or depressed systolic function. These data show that there is a high prevalence of unrecognized moderate to severe MR in patients with acute pulmonary edema, regardless of the presence or absence of LV systolic dysfunction. Furthermore, the prevalence of LV diastolic dysfunction without MR is relatively low even in patients with normal LV systolic function and pulmonary edema. Thus, unrecognized MR may be an important contributor to the syndrome of acute pulmonary edema in patients with normal or depressed LV systolic function.  相似文献   

20.
Diastolic heart failure   总被引:13,自引:0,他引:13  
Primary diastolic failure is typically seen in patients with hypertensive or valvular heart disease as well as in hypertrophic or restrictive cardiomyopathy but can also occur in a variety of clinical disorders, especially tachycardia and ischemia. Diastolic dysfunction has a particularly high prevalence in elderly patients and is generally associated, with low mortality but high morbidity. The pathophysiology of diastolic dysfunction includes delayed relaxation, impaired LV filling and/or increased stiffness. These conditions result typically in an upward displacement of the diastolic pressure-volume relationship with increased end-diastolic, left atrial and pulmo-capillary wedge pressure leading to symptoms of pulmonary congestion. Diagnosis of diastolic heart failure requires three conditions: (1) presence of signs or symptoms of heart failure; (2) presence of normal or slightly reduced LV ejection fraction (EF > 50%) and (3) presence of increased diastolic filling pressure. Assessment of diastolic function can be performed with several non-invasive (2D- and Doppler-echocardiography, color Doppler M-mode, Doppler tissue imaging, MR-myocardial tagging, radionuclide ventriculography) and invasive techniques (micromanometry, angiography, conductance method). Doppler-echocardiography is the most useful tool to routinely measure diastolic function. Different techniques can be used alone or in combination to assess LV diastolic function, but most of them are dependent on heart rate, pre- and afterload. The transmitral flow pattern remains the starting point, since it is easy to acquire and rapidly categorizes patients into normal (E > A), delayed relaxation (E < A), and restrictive (E > A) filling patterns. Invasive assessment of diastolic function allows determination of the time constant of relaxation from the exponential pressure decay during isovolumic relaxation, and the evaluation of the passive elastic properties from the slope of the diastolic pressure-volume (= constant of chamber stiffness) and stress-strain relationship (= constant of myocardial stiffness). The prognosis of diastolic heart failure is usually better than for systolic dysfunction. Diastolic heart failure is associated with a lower annual mortality rate of approximately 8% as compared to annual mortality of 19% in heart failure with systolic dysfunction, however, morbidity rate can be substantial. Thus, diastolic heart failure is an important clinical disorder mainly seen in the elderly patients with hypertensive heart disease. Early recognition and appropriate therapy of diastolic dysfunction is advisable to prevent further progression to diastolic heart failure and death. There is no specific therapy to improve LV diastolic function directly. Medical therapy of diastolic dysfunction is often empirical and lacks clear-cut pathophysiologic concepts. Nevertheless, there is growing evidence that calcium channel blockers, beta-blockers, ACE-inhibitors and AT2-blockers as well as nitric oxide donors can be beneficial. Treatment of the underlying disease is currently the most important therapeutic approach.  相似文献   

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