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Ability of left ventricular stress-shortening relations, end-systolic stress/volume ratio and indirect indexes to detect severe contractile failure in ischemic or idiopathic dilated cardiomyopathy.

The ability of several proposed indirect and direct indexes of left ventricular LV) systolic performance and contractility to detect clinically important LV dysfunction was evaluated in 42 patients with refractory dilated cardiomyopathy studied with right-sided heart catheterization and M-mode echocardiography. Hemodynamic evaluation demonstrated elevated filling pressure (mean pulmonary artery wedge pressure 24 +/- 6 mm Hg) and depressed function (cardiac index 1.68 +/- 0.43 liters/min/m2). Echocardiographic LV end-diastolic dimension (7.3 +/- 1.0 cm), mass (182 +/- 60 gm/m2) and end-systolic stress (163 +/- 44 x 10(3) dynes/cm2) were increased whereas fractional shortening was depressed in all (mean 12 +/- 4%). During follow-up 88% of patients died at a median interval of 16 months after study. Indirect measurements of LV function (mitral E point-septal separation and the ratio of preejection period to LV ejection time) were abnormal in 100 and 88% of patients, respectively. Contractility was classified as depressed in 36 (86%) patients by the end-systolic stress volume index ratio and in 31 (74%) by the relation between fractional shortening and end-systolic stress. In contrast, the relation between end-systolic stress and velocity of circumferential shortening identified only 7 (17%) patients as having subnormal contractility and classified 9 (21%) as having supernormal contractility. Rate correction of velocity of circumferential shortening only modestly improved the ability of the relation to identify depressed contractility (abnormal in 16 patients or 38 percent).

Aged↗

Hemodynamic and renal effects of atrial natriuretic peptide in congestive heart failure.

The hemodynamic and renal effects of anaritide (human atrial natriuretic peptide 102-126), a synthetic analog of atrial natriuretic peptide, were evaluated in 35 patients with chronic New York Heart Association class II to IV heart failure. There were 32 men and 3 women, aged 33 to 75 (mean +/- standard error of the mean 56 +/- 2) years. In the first phase of the study, right-sided heart catheterization was performed, and anaritide was administered as 1-hour infusions. The rate of the infusion varied among patients from 0.03 to 0.3 micrograms/kg/min. In response to anaritide, there were decreases in mean systemic arterial (94 +/- 2 to 87 +/- 2 mm Hg), right atrial (10 +/- 1 to 8 +/- 1 mm Hg), mean pulmonary arterial (33 +/- 2 to 28 +/- 2 mm Hg) and pulmonary artery wedge (22 +/- 2 to 15 +/- 2 mm Hg) pressures (all p less than 0.05). Cardiac index increased (2.39 +/- 0.15 to 2.62 +/- 0.15 liters/min/m2, p less than 0.05) and heart rate was unchanged. Systemic vascular resistance decreased significantly, but pulmonary vascular resistance was unchanged. There were increases in urine volume (1.6 +/- 0.2 to 2.3 +/- 0.4 ml/min), sodium excretion (47 +/- 13 to 74 +/- 20 muEq/min) and fractional excretion of sodium (0.41 +/- 0.11 to 0.59 +/- 0.14%, all p less than 0.05), while potassium excretion and creatinine clearance did not change. In the second phase of the study, patients received 2-hour infusions of anaritide (0.03 to 0.6 micrograms/kg/min) and placebo with noninvasive monitoring.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Pharmacology of angiotensin-converting enzyme inhibitors as a guide to their use in congestive heart failure.

The pharmacokinetics of the angiotensin-converting enzyme (ACE) inhibitors are difficult to assess for several reasons. First, these compounds exert their influence by inhibiting an intermediary enzyme of a cascade of enzymatic events, whose rate-limiting enzyme (renin) is not directly affected by ACE inhibition. Second, renin and angiotensin I accumulate during ACE inhibition and a change in the dose of an ACE inhibitor could produce sudden shifts of angiotensin I to angiotensin II. Third, components of the circulating renin system require the interaction of several organ systems and effector sites. Fourth, the kinetics of ACE inhibitors can be influenced by the organ systems responsible for drug absorption, metabolism and excretion, and the functional status of these systems can be affected by the heart failure process. Fifth, at least some portion of the cardiovascular effects of ACE inhibitors is influenced by the contributions of other systems whose physiologic effects may be of importance in some patients with congestive heart failure. Sixth, the potential impact of tissue-bound ACE is not yet fully understood. Finally, for appropriate drug dosing, the effects of aging on the heart failure process, the extent of renin system activity, and the disposition of ACE inhibitors need to be considered. Because of their complex pharmacokinetics, treatment with ACE inhibitors has been guided by their pharmacodynamic and clinical characteristics.

Age Factors↗

Hemodynamic effects of oral nicorandil in congestive heart failure.

Twenty-five patients with congestive heart failure (CHF) underwent a double-blind randomized study of the acute hemodynamic effects of orally administered nicorandil, a newly developed vasodilator drug. A dose range of 10 to 60 mg was studied. Nicorandil, at a dose of 60 mg, caused statistically significant decreases in systemic systolic and diastolic blood pressure, right atrial pressure, pulmonary capillary wedge pressure, systemic and pulmonary vascular resistance and systolic and diastolic pulmonary arterial pressure. A brief increase in cardiac index attributable to an increase in stroke volume without a change in heart rate was also observed. A dose of 40 mg produced similar results in cardiac index and systemic and pulmonary vascular resistance, but changes in other hemodynamic parameters were much smaller in magnitude and usually not of statistical significance. No significant hemodynamic response was seen to doses of 10 and 20 mg of nicorandil. Duration of action was short with nearly all hemodynamic parameters returning close to baseline within 3 hours. This rapid decrease in activity occurred in concert with a rapid plasma clearance of nicorandil as determined by serial measurements of plasma drug concentration. This study suggests that first-dose orally administered nicorandil elicits favorable, but brief, hemodynamic effects in CHF at doses greater than or equal to 40 mg.

Administration, Oral↗

Exercise-induced secretion of atrial natriuretic factor and its relation to hemodynamic and sympathetic stimulation in untreated essential hypertension.

This study evaluates the release of atrial natriuretic factor (ANF) during maximal exercise in 7 patients with untreated moderate to severe hypertension with invasive monitoring of hemodynamic characteristics in relation to sympathetic activity. Peripheral venous ANF (fmol/ml) was determined at rest and maximal exercise producing a respiratory exchange ratio of 1.14 +/- 0.10. In 5 of 7 patients, simultaneous right ventricular and peripheral venous ANF samples could be obtained to assess exercise myocardial secretion of ANF. With exercise, mean blood pressure increased from 150 +/- 26 to 192 +/- 29 mm Hg (p less than 0.001), pulmonary wedge pressure increased from 7 +/- 3 to 18 +/- 10 mm Hg (p less than 0.05) and ANF increased from 11.7 +/- 8.2 to 25.7 +/- 15.9 (p less than 0.02). This ANF response correlated weakly with pulmonary wedge pressure (r = 0.497, p = not significant), since patients without an increase in pulmonary wedge pressure had no increase in ANF. However, changes in pulmonary wedge pressure and plasma norepinephrine during exercise were inversely correlated (r = -0.811, p less than 0.02), with the greatest increase in norepinephrine occurring with a minimal increase in pulmonary wedge pressure. Similarly, ANF and plasma norepinephrine were inversely correlated during exercise (r = -0.869, p less than 0.05). A significant increase in right ventricular ANF indicated myocardial secretion. Plasma ANF therefore increased because of active myocardial production during exercise in patients with moderate to severe hypertension. These findings further suggest a directionally opposing relation between ANF release resulting from increased atrial tension and sympathetic nervous system influence on cardiac performance during exercise.

Adult↗

Preserved atrial natriuretic peptide secretory function after cardiac transplantation.

The purpose of this investigation was to determine whether atrial natriuretic peptide (ANP) secretory function is preserved after cardiac transplantation. Thirteen hemodynamically stable outpatients performed supine exercise on a bicycle an average of 7 months after orthotopic cardiac transplantation. Right atrial pressure increased 2.2-fold (6 +/- 1 to 13 +/- 2 mm Hg) and pulmonary artery wedge pressure 2.1-fold (11 +/- 1 to 23 +/- 7 mm Hg) with exercise in the transplant recipients. Resting venous ANP level (114 +/- 19 pg/ml) and peak exercise venous level (373 +/- 61 pg/ml) was elevated in transplant recipients (p less than 0.001) compared with control subjects (21 +/- 1 and 92 +/- 14 pg/ml, respectively. This represents a 3.3-fold (114 +/- 19 to 373 +/- 61 pg/ml) increase in the ANP level from resting to exercise in transplant recipients and a 4.4-fold (21 +/- 1 to 92 +/- 14 pg/ml) increase in control subjects. A correlation between venous ANP levels and hemodynamics (right atrial pressure) was observed r = 0.49 p = 0.01. It is concluded that ANP levels at rest are elevated after cardiac transplant, the levels correlate with the intracardiac hemodynamics, and exercise-induced augmentation of plasma levels occurs.

Adult↗

Maintenance of forearm vasodilator action of atrial natriuretic factor in congestive heart failure secondary to ischemic or idiopathic dilated cardiomyopathy.

Infusions of atrial natriuretic factor (ANF) are frequently associated with attenuated natriuretic and diuretic responses in patients with congestive heart failure. However, ANF infusions result in systemic vasodilation, suggesting that end organ responsiveness to ANF may not be uniformly decreased. To determine if the vasodilator effects of ANF were altered in heart failure, strain-gauge plethysmography was utilized to measure forearm blood flow responses to the intraarterial infusion of ANF using a dose range that was low enough to avoid systemic effects. In 9 control subjects, ANF infusions of 0.5, 1.0, 2.0 and 4.0 micrograms/min/100 ml forearm volume significantly increased forearm blood flow from 3.21 +/- 1.71 to 5.69 +/- 3.14, 6.20 +/- 2.57, 6.64 +/- 2.53 and 6.97 +/- 2.49 ml/min/100 ml forearm volume, respectively (all p less than 0.01). In 7 patients with heart failure, ANF infusion significantly increased forearm blood flow from 2.19 +/- 0.98 to 3.18 +/- 1.70, 3.76 +/- 2.0 and 4.42 +/- 2.80 ml/min/100 ml forearm volume for the 0.5, 1.0 and 2.0 micrograms doses, respectively (all p less than 0.05). By analysis of variance, the forearm blood flow responses pooled over all doses were not significantly different between the 2 groups. At the 2.0 micrograms dose, the peak increase in forearm blood flow in normal subjects represented a 107% increase over baseline compared with a 102% increase in patients with heart failure. In summary, these data demonstrate that intraarterial administration of ANF in patients with heart failure resulted in dose-related increases in forearm blood flow. The responses were not significantly different from normal subjects expressed both as an absolute response and as a percent increase.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Management of refractory congestive heart failure.

Despite recent advances in the treatment of congestive heart failure (CHF), many patients continue to present with symptoms refractory to digoxin, diuretic, and vasodilatory therapy. Since it is unlikely that this population will decrease in the near future, practical approaches to management of refractory CHF are reviewed. Refractory CHF here is defined as New York Heart Association (NYHA) functional class III-IV heart failure, despite maximal drug therapy. Before such a diagnosis is made, the patient should be treated with digoxin, diuretics, and a vasodilator. Approach to therapy requires assessment of changing clinical status and pathophysiology, optimizing oral drug treatment, and providing temporary parenteral support when indicated. Specific attention should be given to factors that influence the optimal response to each of these 3 treatment classes. A theoretical, but unproven, concept suggests that combined vasodilatory therapy may be appropriate as long as excessive hypotension is avoided. In the course of management, a decision is required as to whether further optimization of therapy can be achieved on an outpatient basis. Hospital-based intravenous inotropic support given for 2-4 days will often provide the opportunity to restructure patient therapy.

Administration, Oral↗

Effects of successful cardiac transplantation on plasma endothelin.

After cardiac transplantation, cyclosporine-treated patients exhibit a high incidence of systemic hypertension, the mechanism of which is not known. Endothelin, a potent vasoconstrictor peptide of endothelial origin, may be activated by cyclosporine-induced endothelial injury and therefore may mediate post-transplant hypertension. In the present study, we tested whether immunoreactive endothelin-1 could be detected by radioimmunoassay in the plasma of cardiac transplant recipients and if levels correlated with hemodynamic characteristics, cyclosporine level, or renal function as assessed by serum creatinine. Plasma endothelin was measured in 22 stable cyclosporine-treated patients 9 days to 3 years after successful orthotopic cardiac transplantation before routine hemodynamic assessment and surveillance endomyocardial biopsy. Fifteen patients were receiving chronic therapy for hypertension. Plasma endothelin-1 was 5.2 +/- 1.8 pg/ml (range 3.1 to 10.5), which was increased compared with that in 12 normal subjects (1.9 +/- 0.3 pg/ml; range 1.4 to 2.4); the difference was statistically significant (p < 0.0001). Repeated sampling in 8 patients at weekly intervals identified a persistent increase in endothelin with only modest variability. Endothelin-1 did not correlate with any hemodynamic variable, serum creatinine or cyclosporine level. Thus, endothelin-1 is increased after successful orthotopic cardiac transplantation. In the absence of discrete correlations with hemodynamic variables, serum creatinine or cyclosporine levels, both the characteristics and mechanisms for increased endothelin in recipients of cardiac transplants require further evaluation.

Cyclosporine↗

Long-term control of blood pressure by rilmenidine in high-risk populations.

Efficacy and acceptability of rilmenidine in populations with high cardiovascular risk has been established in short- or mid-term studies (1.5-6 months) enrolling relatively small numbers of patients. The present open study was undertaken to compare, on a larger scale, the efficacy and acceptability of a 12-month rilmenidine treatment in high-risk outpatients versus the results obtained in the general population and to check for unexpected adverse events. A total of 2,635 hypertensive patients (supine diastolic blood pressure [SDBP] > 90 mm Hg) were enrolled, including a high-risk population with 1,591 patients aged > 60 (60.3%), 1,007 patients with dyslipidemia (38.2%), 393 with diabetes (14.9%), 328 with chronic renal failure (12.4%), 301 with angina pectoris (11.4%), and 84 with chronic heart failure (3.2%). All patients were treated by rilmenidine 1 mg/day during the first 6 weeks; then (at 1.5 months), if SDBP was > 90 mm Hg, dosage of rilmenidine was 1 mg twice daily during the following 6 weeks. From month 3 to month 12, any other antihypertensive drugs could be added if SDBP remained > 90 mm Hg. In comparison with the general population, the percentage of high-risk patients whose monotherapy normalized blood pressure (SDBP < or = 90 mm Hg) was slightly lower at month 1.5 (58-66%, according to the risk group, vs 68% in the general population) and month 3 (73-82% vs 85%). At month 12, all treatments taken as a whole (monotherapy and combination therapy) led to the normalization of blood pressure in 94% of patients in the general population and in populations at risk.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

Cardiovascular reflexes during long-term converting enzyme inhibition and sodium depletion. The response to tilt in hypertensive patients.

The reflex hemodynamic and humoral response to postural change during long-term renin-angiotensin blockade (captopril) was assessed in sodium-depleted hypertensive patients. Orthostatic hypotension was not observed with head-up tilt or repeated pressure recordings. During tilt, a reflex increase of heart rate occurred (76 +/- 2 to 98 +/- 4 bpm, p less than 0.001). Home recordings demonstrated only minor changes in blood pressure with standing. To evaluate these observations, hemodynamic studies were performed during tilt at three stages of therapy: control, administration of captopril, and administration of captopril plus diuretic. With tilt, no orthostatic hypotension was noted at all three stages of therapy, despite similar peripheral pooling (-22 percent cardiac index). Maintenance of blood pressure was due to reflex increase of heart rate (44, 45 and 38 percent) and systemic resistance (34, 38 and 37 percent). The response to tilt of plasma renin activity was modified by drug therapy, but not completely blocked. This study indicated that long-term converting enzyme inhibition and sodium depletion were safe and did not appreciably blunt the cardiovascular reflexes responsible for prevention of orthostatic hypotension.

Blood Pressure↗

Sympathetic responsiveness and plasma norepinephrine during therapy of chronic congestive heart failure with captopril.

The interaction of cardiac function and sympathetic tone in severe chronic heart failure was evaluated in 24 patients by assessing the cardiac index/plasma norepinephrine relationship. Potential changes were assessed during first-dose and long-term captopril therapy including sympathetic responsiveness to the gravitational stress of head-up tilt. Because cardiac index and norepinephrine levels demonstrated a significant inverse correlation (r = -0.640, p less than 0.001). Norepinephrine decreased from 803 +/- 116 to 635 +/- 76 pg/ml following first-dose captopril therapy (p less than 0.02), with overall hemodynamic improvement. However significant first-dose correlations were not observed. During long-term therapy, norepinephrine decreased from 694 +/- 118 to 457 +/- 106 pg/ml, associated with improvement of symptoms and exercise tolerance. The extent of cardiac index increase was matched by norepinephrine reduction, so that their correlation was maintained (r = -0.540, p less than 0.02). First-dose and long-term therapy were associated with improved responsiveness of sympathetic tone to the reduction of cardiac index induced by the gravitational stress of tilt. In summary, sympathetic tone was increased in severe heart failure, correlating inversely with cardiac function. Although there was improvement of cardiac function with first-dose captopril therapy, significant correlations of supine improvement with reduction of sympathetic tone were noted primarily with long-term therapy. Responsiveness of sympathetic tone to the stress of tilt however, was evident during first-dose and long-term therapy.

Adult↗

Suppression of the renin-angiotensin system by intravenous digoxin in chronic congestive heart failure.

Recent studies have demonstrated that therapy with digitalis preparations may be of inconsistent benefit in the treatment of chronic congestive heart failure. One explanation may be a varying effect on vasoconstrictor hormones, as digoxin has been shown to suppress plasma renin activity in normal and hypertensive persons. Therefore, the effect of short-term digoxin administration on plasma renin activity and plasma aldosterone in six patients with compensated, severe, chronic congestive heart failure was evaluated. Intravenous administration of digoxin (0.50 mg) resulted in a reduction of plasma renin activity from 4.3 +/- 0.9 to 2.0 +/- 0.9 ng/ml per hour and plasma aldosterone from 34 +/- 16 to 14 +/- 6 ng/dl (both p less than 0.05). Maximal response occurred at three hours after administration, with return to baseline by seven hours. Therefore, evaluation of the role of digitalis in chronic heart failure requires consideration of its direct or indirect effect on angiotensin-mediated vasoconstriction and aldosterone-mediated sodium retention, as well as other neurohormonal mechanisms of vasoconstriction.

Adult↗

Evaluation of calcium-mediated vasoconstriction in chronic congestive heart failure.

Intercellular vascular smooth muscle calcium results in vasoconstriction and is therefore a potentially adverse mechanism of increased afterload in chronic congestive heart failure. Therefore, an evaluation was made of supine and tilt hemodynamic data, sympathetic reflexes, and the hormonal response to calcium channel antagonism after administration of nifedipine in nine patients with severe chronic congestive heart failure. After a 10 mg oral dose, the peak hemodynamic response occurred at 30 minutes and was characterized primarily by afterload reduction, improvement of systemic flow, and reduction of pulmonary hypertension. Despite reduction of supine blood pressure, there was no orthostatic hypotension during head-up tilt at the same time of peak response. Reflex responses to sympathetic stimulation (cold pressor test) were improved but still attenuated when compared with normal responses. Plasma renin activity increased significantly, but a dissociation of the aldosterone response was observed. Plasma catecholamine levels were not significantly altered. In summary, calcium antagonism resulted in significant afterload reduction and hemodynamic improvement in chronic congestive heart failure. This was associated with improved reflex responsiveness and, potentially, altered other vasoconstrictor hormones independently of the hemodynamic response. Calcium antagonism may provide a means to further understand vasoconstrictor mechanisms in heart failure and enhance therapy in appropriate patient subsets.

Adult↗

Adverse influence of baroreceptor dysfunction on upright exercise in congestive heart failure.

To test the hypothesis that baroreceptor autoregulation is an important determinant of exercise performance, the hemodynamic responses to the gravitational stress of head-up tilt and upright exercise were assessed in 41 patients with severe chronic congestive heart failure. Three patterns of autonomic dysfunction during head-up tilt were identified. Group A patients had near-normal circulatory reflexes whereas Group B patients experienced orthostatic hypotension and Group C patients lacked the afferent stimulus of venous pooling. Group A patients had a significantly longer exercise duration than both Groups B and C (607 +/- 104 versus 330 +/- 86 and 365 +/- 53 seconds, respectively, p less than 0.05) and a significantly higher double product at peak exercise (17,779 +/- 956 versus 12,235 +/- 869 and 13,760 +/- 998, respectively, p less than 0.05). Thus, baroreceptor abnormalities in the autoregulatory response to postural change are important determinants of the cardiovascular responses required during exercise and influence exercise performance. These abnormalities may help clarify the discrepancies between supine and upright exercise performance and may influence the long-term efficacy of vasodilator therapy in chronic congestive heart failure.

Adult↗

Cellulitis after axillary lymph node dissection for carcinoma of the breast.

We present a series of patients who developed cellulitis following axillary lymph node dissection for carcinoma of the breast. Bacterial cultures were not helpful in making a diagnosis for the majority of the cases. The clinical scenario of upper extremity cellulitis after axillary dissection mimics the presentation of cellulitis in the lower extremity. Until diagnostic methods or treatment advances can eliminate the indications for axillary lymphadenectomy, many women treated for breast cancer will be at long-term risk for the development of cellulitis due to localized immune impairment. Patient and physician awareness of this syndrome is the best available tool to prevent secondary exacerbation of lymphedema. Prompt treatment with appropriate antibiotics appears universally successful. Antistreptococcal antibiotics should not be withheld pending results of blood or tissue cultures, since in only a few cases will a pathogen be isolated. Although there are no studies confirming the concept, it is likely that appropriate treatment for lymphedema may reduce the risk of infection.

Adult↗