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 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Doppler echocardiographic indexes of ventricular inflow have been used clinically to characterize left ventricular (LV) diastolic function. The reliability of these indexes as markers for intrinsic myocardial diastolic properties has been questioned. Micro-manometer left atrial (LA) and LV pressures as well as transmitral Doppler flow velocity signals and M-mode and 2-dimensional echocardiograms were simultaneously recorded. These unique measurements were acquired in patients with dilated cardiomyopathy under baseline conditions and during infusion of high dose amrinone. The response to amrinone was chosen as a hemodynamic model because this drug has previously been described as having beneficial effects on overall LV systolic and diastolic performance. At peak amrinone effect, LV contractility increased (as assessed using load independent end-systolic indexes) and early diastolic relaxation improved whereas passive chamber stiffness, heart rate and stroke volume were unchanged. There was a significant decrease in LV end-diastolic pressure as well as a parallel downward shift of the entire LV diastolic pressure-dimension relation. These findings, which indicated an improvement in overall LV diastolic properties, probably represent the combination of more rapid early diastolic relaxation in conjunction with a reduction in venous return, the relief of pericardial restraint or the reduction in right ventricular-LV interaction. In contrast, the ratios of Doppler-determined peak transmitral early-to-late flow velocities and early-to-late diastolic flow velocity integrals decreased with amrinone infusion, thereby suggesting a drug-induced decrease in LV diastolic compliance. Thus, in patients with idiopathic dilated cardiomyopathy, administration of amrinone has a complex effect on LV diastolic properties.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Comparison of Doppler indexes of left ventricular diastolic function with simultaneous high fidelity left atrial and ventricular pressures in idiopathic dilated cardiomyopathy. 281 70

This study was performed to examine the influence of time during the day and of meals on left ventricular performance in patients with dilated cardiomyopathy and chronic congestive heart failure. Systolic time intervals and echocardiography were performed at set intervals with concomitant hemodynamic measurements in nine patients with chronic congestive heart failure over a 15 hour daytime period and during the three meals. Pulmonary capillary wedge pressure decreased (p less than 0.05) from a non-meal resting peak of 18 +/- 8 mm Hg at 1500 hours to 16 +/- 7 mm Hg at 2200 hours. The other non-meal cardiovascular variables, invasive and noninvasive, did not change significantly during the course of the day. Cardiac output and stroke volume rose and pulmonary and systemic vascular resistances, systemic blood pressure, pulmonary artery pressure, and pulmonary capillary wedge pressure generally fell significantly after meals. Although mean PEP/LVET tended to decrease and delta p/delta t increase after meals, these numerical changes were not statistically significant and none of the other noninvasive variables were affected by meals. Patients with dilated cardiomyopathy and chronic congestive heart failure have modest changes in central hemodynamics over the course of a day with rather striking changes with food ingestion. These alterations are generally not reflected in noninvasive cardiovascular parameters.
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PMID:Left ventricular performance during the course of a day and meals in dilated cardiomyopathy and heart failure. 281 84

The efficacy of dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP) was evaluated in eight patients with heart failure unresponsive to catecholamine therapy. Seven patients who were hemodynamically at Forrester's hemodynamic subset stage H-IV and had a left ventricular stroke work index (LVSWI) of less than 20 g-m/m2 despite administration of unloading drugs and catecholamines were studied both hemodynamically and clinically. Another patient with dilated cardiomyopathy, in whom invasive hemodynamic monitoring could not be carried out, was studied clinically. The DBcAMP was administered intravenously at a mean (+/- SD) of 0.05 +/- 0.036 mg/kg/min, and hemodynamic measurements were made 63 +/- 37 min after administration. The cardiac index (CI) increased from 1.92 +/- 0.22 to 2.49 +/- 0.59 L/min/m2, and LVSWI from 14 +/- 4.0 to 18 +/- 5.1 g-m/m2, both significantly (CI, P less than 0.01; LVSWI, P less than 0.025). The total systemic vascular resistance index (TSVRI) decreased significantly from 2,746 +/- 427.2 to 2,218 +/- 582.6 dan.sec.cm-5.m2 ( P less than 0.01). The increase in CI was accompanied by a proportional decrease in TSVRI in all patients. Left ventricular function, which was estimated by the relation between pulmonary arterial end-diastolic pressure and LVSWI, was improved in five of seven patients after administration of DBcAMP. Two patients in whom DBcAMP was given intermittently improved clinically and survived. The authors conclude that DBcAMP has powerful vasodilating and mild positive inotropic effects and hence can be useful for treating heart failure unresponsive to catecholamines.
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PMID:Efficacy of dibutyryl cyclic AMP in heart failure unresponsive to catecholamines. 282 47

This study was undertaken to clarify the relationship between mild transient hypertension and dilated cardiomyopathy. Fifty-five patients were studied: group 1--controls (12 patients), group 2--hypertensives without clinical evidence of heart failure (14 patients), group 3--patients with hypertensive heart failure and diastolic blood pressure above 100 mmHg (10 patients), group 4--patients with possible dilated cardiomyopathy with mild hypertension, i.e. diastolic blood pressure of 90-100 mmHg (8 patients), group 5--patients with dilated cardiomyopathy and normal blood pressure (11 patients). The haemodynamic status and cardiac contractility indices were measured in each patient on admission, using M-mode echocardiography. Serum sodium and potassium as well as the urinary sodium, potassium and vanillyl mandelic acid excretions were also measured. The stroke volume, cardiac output and cardiac index fell with heart failure, but much more remarkably in group 4. The peripheral vascular resistance was higher in groups 2, 3 and 4 than in groups 1 and 5; so also were the aortic diameter, left posterior wall thickness and left ventricular mass. The plasma volume, aldosterone and cortisol levels were higher and the urinary sodium and potassium excretion lower in patients with heart failure (groups 3, 4 and 5). It is concluded that the raised blood pressure found in some patients suspected to have dilated cardiomyopathy is not due to the haemodynamic and biochemical changes that occur in heart failure. Such patients are 'chronic' hypertensives with hypertensive heart failure. Their presenting blood pressure is low because of their markedly reduced cardiac output.
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PMID:Mild hypertension in patients with suspected dilated cardiomyopathy: cause or consequence? 284 18

The effects of acute intravenous administration of ICI 118,587 (Corwin), a partial beta 1 agonist, were studied in nine patients with dilated cardiomyopathy and symptomatic congestive heart failure. Hemodynamic and metabolic parameters were measured using Swan-Ganz, arterial, and coronary sinus catheters. Repeated doses of Corwin produced no significant change in left ventricular performance, while a trend towards decreased blood pressure and stroke work was seen. No change occurred in coronary sinus blood flow, transmyocardial lactate extraction, or catecholamine release. One patient had significant depression of left ventricular function with hypotension. Thus, acute infusion of Corwin produced no beneficial inotropic responses, but rather produced features suggestive of further myocardial depression.
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PMID:Acute hemodynamic and metabolic effects of ICI 118,587 (Corwin), a selective partial beta 1 agonist, in patients with dilated cardiomyopathy. 286 73

Beta-blockade has been reported to have beneficial hemodynamic effects in chronic congestive heart failure that may be related to alterations in the abnormal neurohumoral profile characteristic of this population. To determine the relationship of the neurohumoral profile to the hemodynamic response to beta-blockade in patients with chronic congestive heart failure, neurohumoral and hemodynamic variables were measured in 10 subjects having congestive cardiomyopathy at baseline and after administration of the beta-blocker pindolol. Baseline stroke index was noted to have an inverse curvilinear relation with plasma norepinephrine (r = -0.69) and renin (r = -0.71) concentration. Pulmonary vascular resistance demonstrated a direct logarithmic relation with plasma norepinephrine concentration (r = 0.68). Increases in norepinephrine, dopamine, and epinephrine concentrations after dosing were noted, with the most marked increase in norepinephrine concentration being coincident with a significant decline in stroke volume index. Two patients not tolerating beta-blockade were characterized by having baseline norepinephrine concentrations 3 SD higher than those of the remaining patients, more marked increases in epinephrine concentration after dosing, and the most profoundly decompensated heart failure at baseline, as defined by the relationship between neurohumoral and hemodynamic variables. These observations suggest that increases in catecholamines after dosing reflect a compensatory response to the adverse hemodynamic-inotropic effects of beta-blockade in congestive heart failure. The neurohumoral profile and the relationship of neuroendocrine to hemodynamic parameters may be useful in delineating patients at risk for adverse hemodynamic effects of beta-blockade.
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PMID:Neurohumoral profile in congestive heart failure: response to beta-blockade. 289 55

Atrial filling fraction, or the fraction of stroke volume resulting from atrial contraction, was measured by Doppler echocardiography from the time-velocity integral of mitral anulus inflow with a method that allows separation of conduit or passive flow from flow resulting from the atrial contraction. The method was validated in 17 patients with externally programmable ventricular demand pacemakers by showing that the time-velocity integral of passive flow (excluding the A wave) during sinus or sequential atrioventricular pacing was almost identical to the time-velocity integral during ventricular pacing. Atrial filling fractions were then measured in 41 normal subjects, aged 20 to 80 years; 28 patients with echocardiographic evidence of concentric left ventricular hypertrophy; 24 with dilated cardiomyopathy (13 of whom had an ischemic origin); and 19 with acute myocardial infarction. Atrial filling fraction increased significantly with age in normal subjects (r = 0.77; p less than 0.001) and ranged from 12% in a 20-year-old man to 46% in a normal 80-year-old woman. In the hypertrophy group, atrial filling fraction had a weak relation with age (r = 0.47; p = 0.006), and the values were significantly higher than in normal subjects. In patients with cardiomyopathy or infarction, atrial filling fraction varied over a wide range and showed no relation to age. Thus, atrial filling fraction as determined by Doppler echocardiography is significantly altered by both age and left ventricular disease. Age-corrected nomograms are essential when assessing atrial filling fraction in individual patients.
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PMID:Quantification of atrial contribution to left ventricular filling by pulsed Doppler echocardiography and the effect of age in normal and diseased hearts. 295 29

Dilated cardiomyopathy, owing to any cause, usually culminates in the clinical syndrome of congestive heart failure. Heart failure is characterized by exertional dyspnea and fatigue, but the precise mechanisms that produce these symptoms are still not clear. Sodium retention occurs early in heart failure, but this disturbance is dynamic in nature and is not always present in the patient. The mechanism of early salt and water retention in heart failure is not defined. Gross edema and ascites occur much later, undoubtedly owing to the convergence of a number of factors. The peripheral adaptations to heart failure include activation of the renin-angiotensin system and the sympathetic nervous system, and the release of AVP. The result is an increase in preload with a resultant increase in stroke volume for some patients, but the price is paid in the form of heightened impedance to ejection and circulatory congestion. The sympathetic nervous system disturbances in heart failure are striking, as disturbances in both circulating and myocardial NE levels are consistently found. Vasorelaxant and natriuretic hormones, as well as certain prostaglandins, may be released in an attempt to offset excessive "compensatory" pressor-sodium retentive mechanisms, but the net result seems to be excessive peripheral vasoconstriction and a downward spiral of deterioration in many patients. One would hope that an unraveling of the complex pathophysiology of heart failure would lead to therapy that would change the natural history of the disease. The results of the first V-HeFT trial give room for cautious optimism in this regard.
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PMID:Pathophysiology of congestive heart failure secondary to congestive and ischemic cardiomyopathy. 304 87

The causes of vascular ischaemic accidents are numerous, and when the brain is involved management is limited to the prevention of similar events. Since cardiac sources of embolism potentially curable, we have prospectively analyzed the results of cardiovascular examinations (including ECG and radiography of the chest) and of echocardiography in 102 patients with cerebral or peripheral vascular ischaemic event in order to determine the impact of echocardiography and the influence of different diagnoses on the need for anticoagulant therapy. Intracardiac thrombi, mitral stenosis, dilated cardiomyopathy, severe left ventricular dysfunction with or without aneurysm and cardiac valve vegetations were regarded as diseases carrying a high risk of embolism, the low risk diseases being mitral valve prolapse, mitral annulus calcification and isolated left atrial dilatation. Atrial fibrillation was treated separately, as it may be associated with several of the diseases listed above. We found 14 diseases with a high risk of embolism (14 p. 100) and 35 diseases with a low risk of embolism (34 p. 100). 10/91 patients with cerebral vascular accident (11 p. 100) and 4/11 patients with peripheral vascular accident presented with a heart disease carrying a high risk of embolism. The most common heart disease with a high risk of embolism (10/14, 71 p. 100) was severe left ventricular dysfunction secondary to a coronary disease or a dilated cardiomyopathy. We did not find more cases of mitral valve prolapse or mitral annulus calcification than in the normal population. 20/29 patients with normal cardiac examination had a normal echocardiogram. The anticoagulant treatment was modified after echocardiography in only one case.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Echocardiographic discoveries in 102 patients with vascular cerebral accidents]. 311 39

There are few data available about the hemodynamic effects of isometric handgrip in severe congestive heart failure and its role in the evaluation of vasodilatory therapy. Therefore, we studied 20 patients with dilated cardiomyopathy at rest, during isometric handgrip, and during supine bicycle exercise before and after a single 25-mg dose of captopril. During handgrip, heart rate (p less than 0.001); systemic vascular resistance (p less than 0.01); systolic, mean, and diastolic pulmonary artery pressure (p less than 0.01) increased significantly; stroke volume index fell (p less than 0.05); whereas mean arterial pressure showed only a small increase, and cardiac index did not change. In contrast, mean arterial pressure and cardiac index increased during dynamic exercise (p less than 0.001), and peripheral resistance decreased (p less than 001). During both handgrip and bicycle exercise, captopril induced a decrease of arterial pressure (p less than 0.01 and p less than 0.001; respectively), peripheral resistance (p less than 0.001 and p less than 0.01; respectively), and systolic (p less than 0.01 and p less than 0.001, respectively) mean (p less than 0.001), and diastolic pulmonary artery pressure (p less than 0.001). Captopril induced and increase in stroke volume index (p less than 0.01) and cardiac index (p less than 0.001 and p less than 0.01 respectively) during both types of exercise.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Isometric exercise for the evaluation of vasodilatory therapy in severe congestive heart failure. 315 12


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