Serum and tissue magnesium concentrations in patients with heart failure and serious ventricular arrhythmias.

Objective: To compare magnesium concentrations in serum and tissue from patients with heart failure. Two groups of patients were compared, those with or without serious ventricular arrhythmias.

Design: Consecutive enrollment.

Influence of positive inotropic therapy on pulsatile hydraulic load and ventricular-vascular coupling in congestive heart failure.

The aortic input impedance spectrum provides a description of the total hydraulic load imposed on the left ventricle and may be used to assess the coupling of the ventricle to the vasculature. The adaptation of the vasculature to positive inotropic intervention was examined in 10 patients with idiopathic dilated cardiomyopathy to test the hypothesis that increased myocardial contractility is matched by complementary changes in aortic impedance that optimize ventricular-vascular coupling and maximize power transfer to the circulation. High fidelity intravascular recordings of aortic pressure and flow were obtained at baseline study and during infusion of dobutamine to derive the aortic input impedance spectrum.

Rest and exercise cardiovascular effects of terazosin in congestive heart failure.

This study investigated the acute effects of the alpha 1 antagonist terazosin on myocardial circulatory responses at rest and during exercise. Ten patients with congestive heart failure (class III and IV) underwent hemodynamic evaluation before and after a 5-mg oral dose of terazosin. At rest and during exercise, terazosin significantly decreased pulmonary capillary wedge pressure, systemic vascular resistance and mean arterial pressure while cardiac index increased.

[Prophylactic irradiation of blood components with conventional radiotherapy devices].

The irradiation of blood components is supposed to be the safest way of the graft versus host reaction prophylaxis. The radiotherapy facilities and compact irradiators for blood preparations and biological materials are used for prophylactic irradiations, practically. The radiotherapy machines allow a homogeneous dose application, but need a high organizing effort.

Magnesium content of serum, circulating mononuclear cells, skeletal muscle, and myocardium in congestive heart failure.

Deranged magnesium concentrations in serum and cardiovascular structures have been implicated in the pathophysiology of hypertension, ischemic heart disease, arrhythmias, and sudden death. This study was conducted to determine the status and interrelation of serum and tissue concentrations of magnesium in patients with congestive heart failure, a clinical setting purportedly predisposed to the development of depleted levels of this cation. Magnesium concentrations of serum, circulating mononuclear cells, skeletal muscle, and myocardium were measured in 23 patients with heart failure on standard therapy.

[Unusual site of misinterpreted bone metastases in irradiated stage IIb cervix cancer].

Bone metastases from cervical carcinoma are rare. Their frequency is reported to be 1.9-4.

Late systolic indices of ventricular function: noninvasive derivation in congestive heart failure.

The slopes of end-systolic pressure/end-systolic dimension and volume relations have been found to be relatively load-independent indices of left ventricular contractility. Noninvasive determination of these relationships has been performed in normal subjects and has been found to reflect baseline and drug-induced changes in ventricular contractility. Three late systolic indices of ventricular contractility were noninvasively determined in subjects with chronic congestive heart failure to determine the feasibility of the method and to assess the linearity and slopes of the relationships in this population.

Cardiovascular pharmacology of dopexamine in low output congestive heart failure.

Dose-response infusions (0.25 to 4.0 micrograms/kg/min) and extended infusions of dopexamine, a new synthetic catechol with beta 2 adrenergic and dopaminergic agonist effects, were performed in 12 patients with low output congestive heart failure (CHF).

Preservation of the end-systolic pressure/end-systolic dimension relation following pindolol in congestive heart failure.

Beta blockade may adversely affect inotropic state of the ventricle, resulting in exacerbation of congestive heart failure in subjects with reduced ventricular function. In normal subjects, ventricular contractility appears to be preserved following administration of beta blockers with intrinsic sympathomimetic activity (ISA). The inotropic state of the ventricle was assessed in seven subjects with congestive heart failure (mean ejection fraction = 23 +/- 5%) before and after administration of the ISA beta blocker, pindolol, with the use of the noninvasively derived end-systolic pressure/end-systolic dimension (ESP/ESD) relation.

Central and regional hemodynamic effects of oral enoximone in congestive heart failure: a double-blind, placebo-controlled study.

Twelve patients with congestive heart failure underwent a double-blind, placebo-controlled study for the purpose of examining the central and regional hemodynamic effects of first-dose (1 and 2 mg/kg) oral enoximone, a new phosphodiesterase III inhibitor. Enoximone augmented cardiac output, generally through a positive chronotropic response. Indices of left ventricular contractility, specifically stroke volume, delta P/delta t, fractional shortening rate, and the duration of the preejection period, were only modestly enhanced by enoximone.

Neurohumoral profile in congestive heart failure: response to beta-blockade.

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.

Extraction and measurement of myocardial nucleotides, nucleosides, and purine bases by high-performance liquid chromatography.

Nucleotides, nucleosides, and purine bases were extracted from human endomyocardial biopsies, freeze-clamped rat hearts, and porcine coronary sinus plasma. Perchloric acid extracts were neutralized with Freon-trioctylamine and analyzed at 250 nm by reverse-phase ion-pairing high-performance liquid chromatography. To achieve the sensitivity necessary for analyzing small (1-3 mg wet wt) tissue samples, a small-bore, 2.

Pulsus alternans induced by inferior vena caval occlusion in man.

To assess the effect of rapid preload reduction on left ventricular performance in nonischemic cardiomyopathy, 11 patients were studied during inferior vena caval (IVC) balloon occlusion. Five developed sustained pulsus alternans. During pulsus alternans, the strong beats demonstrated systolic performance characteristics similar to baseline values, despite a drop in both left ventricular (LV) end-diastolic diameter (66 +/- 13 to 61 +/- 13 mm; p less than 0.

Hemodynamic responses to different levels of alpha-adrenergic interruption in congestive heart failure.

The effects of prazosin, clonidine, and indoramin on central and regional hemodynamic parameters and left ventricular performance were analyzed in a congestive heart failure population to compare the pharmacodynamic responses to different levels of alpha-adrenergic interruption in this condition. The sympathetic nervous system is blocked at the peripheral alpha1-receptor by prazosin, at central nervous system alpha-receptor sites (via alpha-adrenoceptor agonism) by clonidine, and at peripheral and central sites by indoramin. Prazosin and indoramin produced reductions in total systemic and pulmonary vascular resistances, mean systemic and pulmonary artery pressures, and pulmonary capillary wedge pressure with little change in heart rate.

Human myocardial adenosine triphosphatase activities in health and heart failure.

This study was designed to determine: (1) the myocardial adenosine triphosphatase (ATPase) activities of normal humans and patients with dilated cardiomyopathy and (2) whether ATPase activity is related to age, cause and severity of heart failure, and digitalis therapy. Endomyocardial biopsies were performed in 32 subjects. Results from six were normal.

Diastolic time in congestive heart failure.

Diastolic perfusion time is an important determinant of coronary blood flow and subendocardial perfusion. It has been proposed that subendocardial ischemia may exacerbate and perpetuate left ventricular dysfunction in congestive heart failure. Diastolic perfusion time in relation to heart rate was analyzed in 29 digitalized (group 1) and 12 nondigitalized patients (group 2) with heart failure and in 58 normal control subjects.

A preliminary report of the effects of orally administered enoximone on regional hemodynamics in congestive heart failure.

Twelve patients with moderately severe congestive heart failure underwent the simultaneous determination of central and regional hemodynamics after administration of placebo and enoximone. The regions examined hemodynamically included renal, hepatic-splanchnic and upper limb. Enoximone was studied in 2 doses, 1 and 2 mg/kg, and administered in a double-blind, placebo-controlled, crossover design.

Hemodynamic and metabolic responses of the exercising lower limb of humans.

This study was performed to determine the hemodynamic and metabolic responses of the human lower limb during exercise. Blood flow to the lower extremity was measured and sampled for lactate, catecholamines, and oxygen content in 12 normal men at rest, at all stages of bicycle ergometry, and during the postexercise recovery period. Whole body oxygen consumption and cardiac output were recorded throughout the experiment.

An analysis of the determinants of exercise performance in congestive heart failure.

Twenty-nine patients with chronic congestive heart failure underwent symptom-limited maximal exercise to define the determinants and predictors of exercise capacity in this condition. Clinically, the combination of age, cardiothoracic ratio, and left ventricular displacement was moderately predictive of exercise capacity (R2 = 0.44, p = 0.

Safety and efficacy of inferior vena caval occlusion to rapidly alter ventricular loading conditions in idiopathic dilated cardiomyopathy.

To investigate the safety and efficacy of inferior vena caval (IVC) balloon occlusion for preload alteration in humans, 13 patients with dilated cardiomyopathy were studied before and during repeated (total of 78) IVC occlusions. Left and right ventricular (LV and RV) micromanometer pressures were simultaneously measured and M-mode and 2-D echocardiograms were recorded at end expiration. Complications were limited to abdominal discomfort in 2 patients.

Regional myocyte hypertrophy and increased interstitial myocardial fibrosis in hypertrophic cardiomyopathy.

The purpose of this study was to determine if the thickened cardiac walls of patients with hypertrophic cardiomyopathy (HC) are due to increased size or number of myocytes or increased amounts of fibrous tissue. Eight patients, aged 18 to 42 years, who died from complications of HC and 8 age-matched control subjects without heart disease were studied. A 1.