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PubMed1994

Diagnosis and treatment of heart failure based on left ventricular systolic or diastolic dysfunction.

Data from large and small clinical trials reflect major differences in the pathophysiology, treatment, and prognosis of left ventricular (LV) systolic and diastolic dysfunction. These studies also indicate that medical therapy can benefit patients with LV dysfunction regardless of whether or not they are symptomatic. Because the descriptive term congestive heart failure does not provide for these important distinctions, a new classification of LV dysfunction has been developed in which patients with LV dysfunction are categorized on the basis of normal or abnormal systolic function. This classification is based on a simple assessment of LV function, it is applicable to patients without symptoms, and it reflects differences in treatment and prognosis. Those with clinically significant LV systolic dysfunction (ie, an LV ejection fraction < 40%) benefit from therapy whether or not they have symptoms of heart failure. Those with LV dysfunction and a normal LV ejection fraction (ie, diastolic dysfunction) also benefit from medical therapy. Annual mortality is higher in those with systolic dysfunction than in those with diastolic dysfunction, but within each of these categories mortality is higher in those with symptoms than in those without. This classification can be useful in the diagnosis and treatment of individual patients as well as in epidemiologic surveys designed to assess medical practice patterns.

Diastole↗
PubMed1996

Improvement of left ventricular diastolic dysfunction in hypertensive patients 1 month after ACE inhibition therapy: evaluation by ultrasonic automated boundary detection.

The purpose of this study was to detect any improvement in left ventricular diastolic dysfunction in hypertensive patients 1 month after cilazapril therapy. Twenty-three patients, 5 men and 18 women (mean age, 53.52 +/- 9.10 years), with mild or moderate hypertension (160 +/- 13/98 +/- 10 mm Hg), and free of other cardiac or systemic diseases, were studied using ultrasonic automated boundary detection (ABD) and pulsed Doppler echocardiography, before and 1 month after a daily dose of 2.5 mg of cilazapril. The following new ABD diastolic indices were determined: the time rate of area change in early diastole (dA/dt)E, that in late diastole (dA/dt)A, and their ratio (dA/dt)E/(dA/dt)A, while Doppler transmitral flow measurements of left ventricular diastolic filling were also simultaneously recorded. The ABD results showed left ventricular diastolic dysfunction (LVDD) in 9 of 23 patients (39%) compared with the ABD values of 12 normal volunteers. Neither method revealed any significant difference before and after treatment in the patient group as a whole. However, in the group of 9 patients with diastolic dysfunction, the ABD ratio (dA/dt)E/(dA/dt)A was significantly improved after cilazapril therapy (1.20 +/- 0.21 versus 1.41 +/- 0.17; P < 0.05). We concluded that a large percentage (39%) of patients with mild or moderate hypertension had reduced diastolic performance of the left ventricle at a stage of the disease when systolic dysfunction and/or hypertrophy were not evident. Significant improvement of diastolic dysfunction in hypertensive patients could be detected by the proposed ABD new diastolic indices 1 month after cilazapril therapy. In conclusion, automatic boundary detection should be a useful non-invasive modality for the early diagnosis of left ventricular diastolic dysfunction, as well as early recognition of its improvement.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1997

Diastolic dysfunction of the left ventricle. A review of the physiology, causes, diagnosis, treatment and implications.

Diastolic dysfunction of the left ventricle frequently occurs in people with left ventricular hypertrophy and coronary artery disease. It is a common cause of congestive heart failure, especially in the elderly. The mechanism of diastolic dysfunction, its causes, diagnosis and treatment, are reviewed. These are important factors to a Medical Director who must assess the results of non-invasive studies. Alerted by the possibility of diastolic dysfunction, the Medical Director can be more sensitive to other signs and symptoms that may represent early signs of congestive heart failure or ischemia.

Aged↗
PubMed1993

Reversible left ventricular diastolic dysfunction resulting from frequent supraventricular tachycardia.

In two patients with frequent supraventricular tachycardia, echocardiograms revealed remarkable left ventricular systolic and diastolic dysfunction, associated with an absence of left ventricular filling during the early diastolic phase. This dysfunction was detected during normal sinus rhythm as well as tachycardia. By treatment with propafenone, both patients showed dramatic and rapid improvement of symptoms and the left ventricular dysfunction. Left ventricular diastolic dysfunction as well as systolic dysfunction were detected in patients with supraventricular tachycardia, suggesting that frequent supraventricular tachycardia results in severe left ventricular diastolic dysfunction which is reversible after control of the tachycardia.

Aged↗
PubMed1999

Congestive heart failure arising from diastolic dysfunction in the presence of normal left-ventricular systolic function.

Congestive heart failure due to diastolic dysfunction is a common clinical entity, particularly in the elderly. As outlined, such patients fall into a larger group of all patients with CHF symptoms and normal systolic function. When finding "normal" systolic function, the clinician should embark upon a carefully outlined diagnostic work-up geared toward eliminating confounding or treatable contributing causes of dyspnea or typical CHF symptoms. The prognosis for CHF patients with primarily diastolic dysfunction is not as poor as for those with LV systolic dysfunction, although the prevalence, associated morbidity, and costs are great. In contrast to the large number of successful clinical trials that have guided treatment of LV systolic failure, an extremely limited number of trials have specifically addressed themselves to diastolic dysfunction. Marked symptomatic relief can often be provided with careful attention to tailored therapy, although little is known with regard to outcome. Refinements in noninvasive imaging methods and hemodynamic indices of diastolic function may lead to improved patient care.

Diastole↗
PubMed1995

Diastolic dysfunction in patients on thyroid-stimulating hormone suppressive therapy with levothyroxine: beneficial effect of beta-blockade.

Thyroid-stimulating hormone (TSH) suppressive therapy with levothyroxine (L-T4) may cause adverse cardiac effects such as rhythm disturbances and ventricular hypertrophy. The latter is a predisposing condition to diastolic dysfunction. Thus, this study was designed to assess the effect of long-term TSH suppressive therapy on cardiac diastolic function. Because beta-blockade is known to reduce ventricular hypertrophy in patients on L-T4 therapy, we also tried to determine whether the addition of a beta-blocker to L-T4 improved diastolic function. Twenty-five patients (21 female and 4 male; mean age 41 +/- 10 yr) on TSH suppressive therapy for 3-9 yr (9 for differentiated carcinoma and 16 for nontoxic goiter) and 20 control subjects were studied. A subgroup of 10 patients, selected for the presence of symptoms and signs of adrenergic overactivity, was treated for 4 months with the beta-blocker bisoprolol (4.25 +/- 1.2 mg/day), and their maintaining L-T4 therapy was unchanged. In the patient group, left ventricular mass was significantly increased (P < 0.001), isovolumic relaxation time was prolonged (P < 0.001), and early diastolic filling velocity was markedly reduced (P < 0.001), whereas late diastolic filling was increased (P < 0.005). Consequently, the early-to-late diastolic flow velocity ratio was markedly decreased (P < 0.001). These alterations were more pronounced in the subgroup of patients with evidence of adrenergic overactivity. In these patients, beta-blockade induced a significant regression of cardiac hypertrophy and improved diastolic dysfunction. In particular, isovolumic relaxation time decreased (P < 0.01) and the early-to-late flow velocity ratio increased significantly (P < 0.01). Both indices reached values after beta-blockade that were no longer different from those of asymptomatic patients. It is concluded that long-term L-T4 therapy increases myocardial mass and causes relevant diastolic dysfunction, particularly in those patients with evidence of mild hyperthyroidism and adrenergic overactivity. Both myocardial hypertrophy and diastolic dysfunction are significantly improved by adrenergic beta-blockade.

Adult↗
PubMed1993

Isolated diastolic dysfunction of the myocardium and its response to CoQ10 treatment.

Symptoms of fatigue and activity impairment, atypical precordial pain, and cardiac arrhythmia frequently precede by years the development of congestive heart failure. Of 115 patients with these symptoms, 60 were diagnosed as having hypertensive cardiovascular disease, 27 mitral valve prolapse syndrome, and 28 chronic fatigue syndrome. These symptoms are common with diastolic dysfunction, and diastolic function is energy dependent. All patients had blood pressure, clinical status, coenzyme Q10 (CoQ10) blood levels and echocardiographic measurement of diastolic function, systolic function, and myocardial thickness recorded before and after CoQ10 replacement. At control, 63 patients were functional class III and 54 class II; all showed diastolic dysfunction; the mean CoQ10 blood level was 0.855 micrograms/ml; 65%, 15%, and 7% showed significant myocardial hypertrophy, and 87%, 30%, and 11% had elevated blood pressure readings in hypertensive disease, mitral valve prolapse and chronic fatigue syndrome respectively. Except for higher blood pressure levels and more myocardial thickening in the hypertensive patients, there was little difference between the three groups. CoQ10 administration resulted in improvement in all; reduction in high blood pressure in 80%, and improvement in diastolic function in all patients with follow-up echocardiograms to date; a reduction in myocardial thickness in 53% of hypertensives and 36% of the combined prolapse and fatigue syndrome groups; and a reduced fractional shortening in those high at control and an increase in those initially low.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Left ventricular diastolic dysfunction as a cause of congestive heart failure. Mechanisms and management.

OBJECTIVE: To define the mechanisms underlying left ventricular diastolic dysfunction in patients with congestive heart failure and normal systolic function and to identify the patients at risk for this syndrome. STUDY SELECTION: Studies were selected that describe the clinical observations of congestive heart failure with normal systolic function and that provide experimental and clinical insights into the mechanisms responsible for ventricular diastolic dysfunction. DATA SYNTHESIS: Recent studies indicate that a large number of patients (up to 40% in some series) presenting with congestive heart failure have preserved left ventricular systolic function. The factors contributing to altered left ventricular diastolic function include fibrosis, hypertrophy, ischemia, and increased afterload. The latter three factors, alone or in combination, predispose to impaired left ventricular relaxation, an active energy-requiring process. Thus, decreased left ventricular diastolic distensibility (increased diastolic pressure at any level of diastolic volume) may arise not only from altered passive elastic properties stemming from fibrosis or increased muscle mass but also from derangements in the dynamics of ventricular relaxation. RESULTS: In patients with essential hypertension, all four of the above mechanisms may be operative. Considering the prevalence of hypertension in the general population, hypertension appears to be an important underlying factor in many patients with heart failure on the basis of diastolic mechanisms. In the patient presenting with dyspnea and elevated filling pressures, but with a nondilated, normally contracting ventricle, treatment with standard heart failure medications (such as digitalis, diuretics, and vasodilators) is often ineffective and may be deleterious. Such patients may respond more favorably to beta-blockers and calcium-channel blockers. CONCLUSIONS: Diastolic dysfunction should be considered in the patient presenting with heart failure symptoms but with normal systolic function, particularly in hypertensive patients with left ventricular hypertrophy.

Diastole↗
PubMed1998

Postoperative pulmonary edema secondary to diastolic dysfunction in a patient with a previous heart transplant.

Left ventricular diastolic dysfunction with preserved contractility is being recognized with increasing frequency. We describe a 53-year-old man who had undergone heart transplantation 10 years previously, who was now scheduled for renal biopsy for progressive and unexplained decline in renal function. Hypertension from pain or a stress response, increases in preload, and tachycardia predispose patients with chronic left ventricular diastolic dysfunction to pulmonary edema. Prompt and accurate diagnosis is essential for treatment. We recommend echocardiographic assessment of diastolic function when preoperative evaluation of left ventricular function is considered for these patients.

Biopsy↗
PubMed1992

Exacerbation of left ventricular ischemic diastolic dysfunction by pressure-overload hypertrophy. Modification by specific inhibition of cardiac angiotensin converting enzyme.

Hearts with compensatory pressure-overload hypertrophy show an increased intracardiac activation of angiotensin II that may contribute to ischemic diastolic dysfunction. We studied whether pressure-overload hypertrophy in response to aortic banding would result in exaggerated diastolic dysfunction during low-flow ischemia and whether the specific inhibition of the cardiac angiotensin converting enzyme by enalaprilat would modify systolic and diastolic function during ischemia and reperfusion in either hypertrophied or nonhypertrophied hearts. Isolated, red blood cell-perfused isovolumic nonhypertrophied and hypertrophied rat hearts were subjected to enalaprilat (2.5 x 10(-7) M final concentration) infusion during 20 minutes of baseline perfusion and during 30 minutes of low-flow ischemia and 30 minutes of reperfusion. Coronary flow per gram was similar in nonhypertrophied and hypertrophied hearts during baseline perfusion, ischemia, and reperfusion. At baseline, left ventricular developed pressure was higher in hypertrophied than nonhypertrophied hearts in untreated groups (224 +/- 8 versus 150 +/- 9 mm Hg; p less than 0.01) and in enalaprilat-treated groups (223 +/- 9 versus 145 +/- 8 mm Hg; p less than 0.01). During low-flow ischemia, left ventricular developed pressure was depressed but similar in all groups. All groups showed deterioration of diastolic function; however, left ventricular end-diastolic pressure increased to a significantly higher level in untreated hypertrophied than in nonhypertrophied hearts (65 +/- 7 versus 33 +/- 3 mm Hg; p less than 0.001). Enalaprilat had no effect in nonhypertrophied hearts, but it significantly attenuated the greater increase in left ventricular end-diastolic pressure in hypertrophied hearts treated with enalaprilat compared with no drug (65 +/- 7 versus 50 +/- 5 mm Hg; p less than 0.01). The beneficial effect could not be explained by differences in coronary blood flow per gram left ventricular weight, glycolytic flux as reported by lactate production, myocardial water content, oxygen consumption, and tissue levels of glycogen and high energy phosphate compounds. During reperfusion, all hearts showed a partial recovery of developed pressure to 70-74% of initial values. No effect of enalaprilat could be detected during reperfusion on systolic and diastolic function or restoration of tissue levels of high energy compounds. In conclusion, our experiments show that hypertrophied red blood cell-perfused hearts manifest a severe impairment of left ventricular diastolic relaxation in response to low-flow ischemia in comparison with control hearts. Further, our experiments support the hypothesis that the enhanced conversion of angiotensin I to angiotensin II in rats with pressure-overload hypertrophy contributes to the enhanced sensitivity of hypertrophied hearts to diastolic dysfunction during low-flow ischemia.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1986

Alpha-adrenergic mechanisms in the pathophysiology of left ventricular heart failure--an analysis of their role in systolic and diastolic dysfunction.

Alpha-adrenoceptor (alpha-AR) mechanisms may contribute to systolic and diastolic dysfunction of the left ventricle. Centrally acting alpha 2-AR agonist drugs, including methyldopa, clonidine, and guanabenz, activate brainstem alpha 2-AR and this activation results in a decrease in overall sympathetic tone and an increase in parasympathetic tone. Peripherally acting alpha 1-AR antagonists, such as prazosin, inhibit the actions of catecholamines at post-synaptic receptor sites. Heart failure is characterized by hyperactivity of sympathetic pathways and parasympathetic withdrawal. In this situation, alpha 2-agonists reduce sympathetic activity and improve hemodynamic parameters of cardiac function; both acute and chronic administration of alpha 2-AR have been demonstrated to reduce serum catecholamine levels, heart rate, and arterial blood pressure, and to improve exercise performance. Diastolic dysfunction of the left ventricle is characterized by a marked decrease in ventricular compliance, often a result of hypertension and left ventricular hypertrophy; the end result is an increase in left ventricular filling pressure and pulmonary venous pressure. Treatment with alpha 2-AR, by decreasing sympathetic tone and blood pressure, and alpha 1-AR antagonists, by reducing blood pressure and by directly inhibiting the actions of catecholamines at alpha 1-AR, may produce a reduction in the degree of ventricular hypertrophy and improve diastolic performance of the left ventricle. Thus, therapeutic intervention in heart failure with either alpha 2-AR agonists or alpha 1-AR antagonists may favorably modulate these alterations in sympathetic tone and improve ventricular function.

Adrenergic alpha-Antagonists↗
PubMed1988

Effects of increasing afterload on early diastolic dysfunction in hypertrophic non-obstructive cardiomyopathy.

The effects of increasing afterload on early diastolic dysfunction in 10 patients with hypertrophic non-obstructive cardiomyopathy were studied by computer assisted analyses of digitised M mode echocardiograms. Infusion of angiotensin II increased the end systolic pressure by a mean (SD) of 36.2 (10.3) mm Hg. As the afterload increased early diastolic dysfunction tended to become more normal: the interval and the change in dimension between minimal cavity dimension and mitral valve opening decreased and the duration of rapid diastolic filling and the accompanying change in dimension increased. None the less, the end diastolic dimension and thus the overall diastolic filling remained unchanged. Impaired early diastolic function in hypertrophic cardiomyopathy is at least partly caused by altered loading conditions.

Adult↗
PubMed1996

Echocardiographic assessment of left ventricular hypertrophy diastolic dysfunction and pericardial disease in patients on maintenance haemodialysis.

Echocardiographic study of sixty patients on maintenance haemodialysis (MHD) was undertaken to determine the prevalence and factors associated with left ventricular (LV) hypertrophy (LVH), LV diastolic dysfunction and pericardial disease. The mean age was 34.4 (standard deviation 13.0), range 14-66 years with 31 (51.7%) men. LVH was found in 41 (68%) patients. Of the factors analysed, serum calcium and calcium-phosphate product were significantly associated with LVH (t = 2.01, df = 58, p = 0.046; t = 2.18, df = 58, p = 0.032 respectively). Hypertension in this study was not significantly associated with LVH (p = 0.169). LV diastolic dysfunction was found in 23/41 (56%) patients with LVH, and in 9/19 (47%) patients without LVH (difference is not statistically significant, X2 = 0.12, df = 1, p = 0.725). Small pericardial effusions were detected in 4/60 (7%) patients and two patients had pericardial thickening. We conclude that in our MHD patients LVH, is very common and that diastolic dysfunction is observed equally in patients with and without LVH. However, haemodynamically significant pericardial effusions are rare in patients who have been on dialysis for at least six months.

Adolescent↗
PubMed1991

Doppler echocardiographic evaluation of diastolic dysfunction.

Recently, considerable effort has been directed toward the application of Doppler methods for detecting diastolic dysfunction. Recordings of transmitral filling velocity as obtained from pulsed-wave Doppler have been extensively investigated as a noninvasive method for determining left ventricular diastolic filling properties. Although Doppler parameters appear to reflect volumetric transmitral flow, close correlations with invasive descriptors of diastolic performance have not been found. Furthermore, Doppler transmitral velocities are sensitive to changes in ventricular preload, afterload, and heart rate. However, at least two distinct Doppler spectral patterns have been identified that are associated with impaired ventricular relaxation and restrictive physiology. Thus, Doppler recordings have proven to be of value in identifying the presence and type of diastolic dysfunction, and in the future they may be helpful in following the response to therapeutic interventions. The purpose of this paper is to review the available information relating Doppler transmitral recordings with catheterization and clinical descriptors of diastolic function. Additionally, the aim is to provide an understanding of the value and limitations of these noninvasive measurements in identifying and treating patients with diastolic abnormalities.

Amyloidosis↗
PubMed1993

Diastolic dysfunction as a cause of heart failure.

Diastolic dysfunction is an important cause of symptoms in patients with various types of cardiac disease. Increased left ventricular diastolic pressure may lead to pulmonary congestion, even in the setting of normal left ventricular systolic function. Although the physiology of diastolic function is complex, left ventricular diastolic pressure may become elevated through one of three broad mechanisms. Abnormalities intrinsic to the left ventricle may include 1) impaired left ventricular relaxation, a finding that is common in most cardiac diseases and may be particularly important during ischemia; 2) increased left ventricular wall thickness relative to cavity volume, which will shift the diastolic pressure-volume relation such that the same volume is associated with a higher pressure; and 3) increased myocardial stiffness, which is thought to be associated with interstitial fibrosis or scar tissue formation. In addition, diastolic pressures may become elevated because of factors extrinsic to the left ventricle. These may include 1) increased central blood volume, which will increase left ventricular pressure without altering the left ventricular pressure-volume relation; and 2) ventricular interaction mediated by pericardial restraint, which may cause a parallel upward shift of the diastolic pressure-volume relation. Treatment of the factors extrinsic to the left ventricle tends to be much more successful than treating abnormalities that are intrinsic to the ventricle. Improved understanding of myocardial relaxation at the cellular level and delineation of the molecular regulation of myocyte hypertrophy and fibroblast proliferation may lead to new and innovative approaches to the treatment of heart failure.

Animals↗
PubMed1992

Comparison of simultaneous Doppler echo and apexcardiogram in detecting left ventricular diastolic dysfunction in patients with systemic hypertension.

Patient with systemic hypertension have often abnormalities of left ventricular (LV) diastolic function. Although pulsed Doppler echocardiography (PDE) is at present time the only simple widely used noninvasive method for evaluating such LV diastolic dysfunction, LV apexcardiogram (ACG) reflecting LV pressure curve changes can also be useful for evaluating LV diastolic events. In order to compare the validity of these two methods in assessing LV diastolic dysfunction, PDE and ACG were simultaneously obtained in 29 patients with chronic systemic hypertension and in 61 controls. As diastolic indices of PDE served the peak early (E) and late atrial (A) diastolic transmitral flow velocities, the A/E ratio and the deceleration time; and of the ACG the relative A-wave to total height (A/H), the total relaxation time (TART), the heart rate corrected TART and the combined index DATI (= diastolic amplitude time index). In patients with hypertension, from the PDE only A and A/E ratio were significantly different from the controls, whereas all mentioned ACG indices showed an abnormal mean value. Thus, the less widely used ACG appears to be a more accurate method in the noninvasive evaluation of diastolic mechanical events than the routinely used PDE in patients with chronic hypertension.

Chronic Disease↗
PubMed1997

Role of MgADP in the development of diastolic dysfunction in the intact beating rat heart.

Sarcomere relaxation depends on dissociation of actin and myosin, which is regulated by a number of factors, including intracellular [MgATP] as well as MgATP hydrolysis products [MgADP] and inorganic phosphate [Pi], pHi, and cytosolic calcium concentration ([Ca2+]c). To distinguish the contribution of MgADP from the other regulators in the development of diastolic dysfunction, we used a strategy to increase free [MgADP] without changing [MgATP], [Pi], or pHi. This was achieved by applying a low dose of iodoacetamide to selectively inhibit the creatine kinase activity in isolated perfused rat hearts. [MgATP], [MgADP], [Pi], and [H+] were determined using 31P NMR spectroscopy. The [Ca2+]c and the glycolytic rate were also measured. We observed an approximately threefold increase in left ventricular end diastolic pressure (LVEDP) and 38% increase in the time constant of pressure decay (P < 0.05) in these hearts, indicating a significant impairment of diastolic function. The increase in LVEDP was closely related to the increase in free [MgADP]. Rate of glycolysis was not changed, and [Ca2+]c increased by 16%, which cannot explain the severity of diastolic dysfunction. Thus, our data indicate that MgADP contributes significantly to diastolic dysfunction, possibly by slowing the rate of cross-bridge cycling.

Adenosine Diphosphate↗
PubMed1999

Diastolic dysfunction and collagen structure in canine pacing-induced heart failure.

Heart failure is characterized not only by systolic, but also by diastolic dysfunction. The present study tested whether or not diastolic dysfunction is associated with changes in tissue properties and collagen network structure. Heart failure was induced in seven chronically instrumented, conscious dogs by rapid left ventricular pacing (2 50 min(-1)). After 2-5 [mean: 4+/-1 (S.D.)] weeks pacing, heart failure was apparent from clinical symptoms (ascites, cachexia, edema, exercise intolerance) and hemodynamic parameters (significant increases of heart rate and left ventricular end-diastolic pressure and decreases of left ventricular maximal pressure, dP/dtmax and systolic wall thickening). The left ventricle was dilated, as indicated by a decrease of end-diastolic wall thickness (6.3+/-2.0 v 7.2+/-2.1 mm; P<0.05; sonomicrometry). The left ventricular end-diastolic pressure-strain relation (strain: relative change of end-diastolic wall thickness) was obtained during alterations of loading conditions by inferior caval vein and descending thoracic aortic occlusion. The slope of this relation increased from 85+/-20 to 428+/-188 in heart failure, indicating an increase of left ventricular stiffness. Collagen was stained with picrosirius red and analyzed using polarized light microscopy. In heart failure, the collagen volume fraction remained unchanged (1.9+/-1.2 v 2.3+/-1.3%; N.S.), while the nonuniformity of collagen orientation, as reflected by its standard deviation, was increased (11.1+/-1.8 v 6.1+/-0.4 o; P<0.05). The nonuniformity of collagen fiber orientation correlated with left ventricular stiffness [r=0.75].

Animals↗