Different effects of baclofen on LH and cortisol responses to naloxone in normal men.

The possible involvement of GABAergic B receptors in the control of LH and ACTH/cortisol secretion in response to naloxone was evaluated in seven normal men. Subjects were tested with naloxone (4 mg IV bolus plus 10 mg infused over 2 hr) with or without previous treatment with the gamma-aminobutyric acid (GABA)-ergic B receptor agonist, baclofen (5, 10 or 15 mg PO 30 min before naloxone). In additional experiments, six normal men were tested with 15 mg baclofen or placebo 30 min before a 2-hr infusion of normal saline. Plasma cortisol levels rose 70% in response to naloxone. The naloxone-induced cortisol rise was not modified by pretreatment with baclofen (5, 10 or 15 mg). Plasma LH concentrations rose 66% in response to naloxone. When the lowest dose of baclofen (5 mg) was administered, the LH response to naloxone remained unchanged. In contrast, 10 mg baclofen produced a significant reduction, and 15 mg baclofen completely abolished the naloxone-induced LH rise. The administration of baclofen or placebo alone did not change basal plasma levels of cortisol and LH. These data suggest that, in normal men, GABA B receptors participate in the endogenous opioidergic control of LH secretion, but not of ACTH/cortisol secretion.

[High-resolution electrocardiography evaluation of late potentials. A comparison between Frank XYZ orthogonal leads and standard precordial electrocardiographic leads]. / Determinazione mediante elettrocardiografia ad alta risoluzione dei potenziali tardivi. Confronto fra le derivazioni ortogonali XYZ di Frank e le derivazioni elettrocardiografiche precordiali standard.

High-resolution electrocardiography has been used as a non-invasive method for the study of delayed potentials in order to evaluate the risk of the onset of ventricular arrhythmia first in ischaemic cardiopathy and then in various cardiopathies, generally using XYZ orthogonal derivations. The aim of this study was to compare the results obtained with those using standard precordial leads, in particular V4 and V6 leads. A group of 28 patients, males and females, aged between 15 and 55 years of age, was examined. All patients were suffering from different cardiopathies. Subjects with delayed right and left ventricular activation on the surface ECG tracing were excluded from the study. A 60-200 Hertz bandpass filter and time averaging of 300 consecutive complexes were used to analyse tracings. Dual recordings were performed for each patient. The following parameters were examined: total duration of filtered QRS complex and root-mean-square voltage of potentials in the last 40 msec of filtered QRS (RMS). In particular, the comparison between RMS using Frank's method and those obtained using V4 and V6 precordial leads provided a coefficient of correlation of r = 0.91 with p < 0.001 and r = 0.92 with p < 0.001 respectively, and the comparison between QRS obtained using the same method and that obtained using V4-V6 precordial leads gave a coefficient of correlation of R = 0.80, p < 0.001 and r = 0.77 and p < 0.001 respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Echocardiographic study in acromegalic patients.

To assess left ventricular function in acromegaly, M-mode echocardiograms were obtained from 25 patients with acromegaly (A). Echocardiographic tracings of the septum, posterior wall and anterior mitral valve leaflet were analyzed by computer and compared with those of 25 age matched normal subjects (C). Acromegalic patients had a marked increase of the septum, posterior wall thickness and left ventricular muscular mass (p < 0.001). Furthermore, in A an increased change of left ventricular dimension during isovolumic relaxation period (IRP) (p < 0.001), e prolongation of the duration of the IRP (p < 0.001 and a reduction of the percentage dimension change during the rapid filling period (p < 0.01) were shown. We suggest that impairment of some aspects of diastolic function is common and may be the primary abnormality in left ventricular function in acromegaly.

[Echocardiographic changes in patients with polycystic nephropathy]. / Alterazioni ecocardiografiche in pazienti affetti da nefropatia policistica.

We have studied with the echocardiography M-Mode, 2-D, Doppler three groups of 15 subjects for testing the presence of cardiac abnormalities probably related to primary collagen defect in patients with autosomal dominant polycystic kidney disease (ADPKD) The first group was made up of patients with ADPKD and normal renal function, the second of patients with ADPKD in hemodialysis (HD), the last one of patients in HD for other renal disease. In the first group we found no cardiovascular abnormalities while we found an increased incidence of valvular disease (p = 0.016) in patients with ADPKD in HD and an increased incidence in valvular disease (p = 0.016) and left atrial dilatation (p = 0.006) in patients in HD for different renal disease. When we estimated the cases on the ground of dialytic age uncorrelated with the initial renal disease, only the incidence of valvular calcifications was increased in patients on HD more than 3 years (p = 0.034). In our group of patients the echocardiographic abnormalities seem to be related more to uremic cardiomyopathy even if we cannot deny the existence of primary cardiac disease in patients with ADPKD.

Effect of potentiation of cholinergic tone by pyridostigmine on the GH response to GHRH in elderly men.

The plasma GH response to GHRH (100 micrograms i.v.) was evaluated either alone or after pretreatment with pyridostigmine (120 mg orally 1 h prior to GHRH) in 9 younger men (age range: 22-39 years) and in 9 healthy elderly men (age range: 63-77 years). On a different occasion, subjects were tested with pyridostigmine alone. Basal concentrations of glucose, cortisol, androgens, estrogens, thyroid hormones and GH were similar in all subjects, whereas insulin-like growth factor was lower in elderly men. The GH response to GHRH was significantly lower in the older (mean peak was 6 times higher than baseline) than in the younger group (mean peak was 11.3 times higher than baseline). The pretreatment with pyridostigmine induced a striking increase in the GH response to GHRH in the younger subjects (mean peak was 26 times higher than baseline), whereas it produced only a slight increase in the GHRH-induced GH response in elderly men (mean peak was 8.7 times higher than baseline). When pyridostigmine was given alone, plasma GH levels rose significantly in both groups; however, the pyridostigmine-stimulated GH response was significantly higher in younger (mean peak was 6 times higher than baseline) than in older subjects (mean peak was 2.5 times higher than baseline). These data indicate that the cholinergic stimulatory regulation of GH release is reduced in elderly subjects. Since acetylcholine inhibits hypothalamic somatostatin release, the reduced cholinergic tone in elderly subjects may result in an increased somatostatinergic tone.

[Late potentials in patients with prolapse of the mitral valve]. / Studio dei potenziali tardivi in pazienti con prolasso della valvola mitrale.

Recently published reports have highlighted the presence of a high incidence of late potentials in patients with mitral valve prolapse. In order to verify this observation 29 patients suffering from this pathology were studied using high-resolution electrocardiography. Late potentials were present in 24% of patients with mitral valve prolapse in comparison to 5% of control subjects (p less than 0.05); no correlation was found however in patients with mitral valve prolapse between the presence of late potentials and Holter's ventricular hyperkinetic tachycardia. At a follow-up after 16 +/- 4 months no patient presented persistent ventricular tachycardia or sudden death. The presence of late potentials might be yet symptom of the mitral prolapse syndrome whose prognostic role, although not yet clear, does not appear to represent a negative factor in relation to major tachycardia attacks.

Restoration of normal growth hormone responsiveness to GHRH in normal aged men by infusion of low amounts of theophylline.

In order to establish whether the age-related reduced growth hormone (GH) responsiveness to GH-releasing hormone (GHRH) could be improved by treatment with low amounts of theophylline, a drug mainly acting through cyclic adenosine 3', 5'-monophosphate (cAMP), and calcium-mediated mechanisms, eight adult subjects (aged 20-37) and eight elderly men (aged 64-79) were tested with GHRH (50 micrograms in an iv bolus), theophylline (1.67 mg/min for 3 h), or the combination of both drugs. The GH response to GHRH was significantly lower in the older than in the younger group (mean peaks were 4.5 and 7.5 times higher than baseline, respectively). Theophylline did not change basal GH levels in any subjects and GHRH-induced GH rise in the younger group, whereas it restored normal GH responses to GHRH in the older subjects (mean peak responses were eight times higher than baseline in both groups). These data show that in elderly subjects the mechanism underlying the GHRH-induced GH secretion may be fully activated by GHRH during treatment with low amounts of theophylline.

Restoration of normal gonadotropin responses to naloxone by chronic bromocriptine treatment in elderly men.

Naloxone is unable to stimulate FSH and LH secretion in elderly men, suggesting a reduced endogenous opioid control of gonadotropin secretion in senescence. In the present study, we examined whether in elderly men a chronic dopaminergic stimulation with bromocriptine (5 mg/day for 7 days) modifies the gonadotropin response to naloxone (4 mg as an i.v. bolus plus 10 mg infused in 2 h). Eleven younger men (group 1, 22-40 years old) participated as controls. Twenty-two elderly men were selected from a larger population and were divided into two groups: subjects with compensated gonadal failure (normal blood testosterone and elevated gonadotropin concentrations; group 2, n = 11; 62-80 years old) and men with normal gonadal function (normal blood testosterone and gonadotropin levels; group 3, n = 11; 61-82 years old). Naloxone induced a striking LH and a slight but significant FSH increase in group 1, but was unable to change serum gonadotropin concentrations in elderly subjects of both groups 2 and 3. When experiments were repeated after bromocriptine treatment, no significant differences in LH and FSH responses to naloxone were observed in the younger subjects. On the other hand, bromocriptine restored significant gonadotropin responses to naloxone in elderly men. In fact, after bromocriptine, naloxone-induced FSH and LH increments in groups 2 and 3 were indistinguishable from those observed in group 1. These data suggest that in men age-related dopaminergic alterations may underlie the defective endogenous opioid control of gonadotropin secretion.

[A case of rupture of the tendinous cord caused by infective endocarditis]. / Considerazioni su un caso di rottura di corda tendinea da endocardite infettiva.

The paper reports a case of infective endocarditis of the valve, with an insidious and slow onset accompanied by low fever, debility, loss of weight, anemia, and the concomitant echocardiographic observation of pericardial effusion. Subsequent echocardiographic tests produced images which probably referred to valvular vegetation. As a matter of fact these findings proved to be result of the rupture of the latero-posterior tendinous cord of the mitral flap and other similar cords whose stumps, covered in fibrin, had adhered to the edge of the anterior cups. This finding was discovered during surgery, which was performed early and successfully, and was followed by excellent long-term results.

Evaluation of noninvasive alternatives to right heart catheterization.

We mechanocardiographically evaluated 50 patients with acute myocardial infarction, invasively monitored by Swan-Ganz catheters, in order to assess if mechanocardiography could provide reliable hemodynamic informations. The last 25 subjects were also studied by pulsed Doppler echocardiography. Our results confirm the high precision of apexcardiography in assessing mean pulmonary capillary wedge pressure (r = 0.91) while Doppler echocardiography proved itself better than mechanocardiography in assessing cardiac output (r = 0.82 vs r = 0.78). Moreover, Doppler echocardiography allowed a good estimation of mean pulmonary artery pressure (r = 0.81) which cannot be assessed by other noninvasive methods. However, we could not find any clinically useful relationship between Doppler mitralic flow characteristics and mean pulmonary capillary wedge pressure. Therefore noninvasive methods could represent a valid alternative to right heart catheterization provided that an integrated Doppler echocardiographic and mechanocardiographic approach is used.

Different effects of aging on the opioid mechanisms controlling gonadotropin and cortisol secretion in man.

The present study was undertaken in order to assess the influence of aging on the endogenous opioid control of gonadotropin and adrenocorticotropin/cortisol secretion in man. For this purpose, the capability of the opioid antagonist naloxone to increase circulating levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and cortisol was tested in male subjects of different ages. Thirty normal men were randomly chosen and divided into 3 groups by age: group I = 22-40 years (n = 10); group II = 41-59 years (n = 10); group III = 62-80 years (n = 10). Since the men of group III showed higher basal serum gonadotropin concentrations than the subjects of group I and group II, we selected from a large population a fourth group of elderly men with normal basal LH and FSH levels: group IV = 61-82 years (n = 7). All subjects were tested for 120 min during the intravenous administration of naloxone (4 mg given in an intravenous bolus at time 0, plus 10 mg infused for 2 h). Control tests with normal saline instead of naloxone were performed in all groups. All subjects had similar blood testosterone and cortisol levels, whereas LH and FSH concentrations were significantly higher in group III than in groups I, II and IV. Naloxone increased plasma cortisol concentrations by 50% in all groups. The cortisol secretory response followed a similar pattern regardless of age.(ABSTRACT TRUNCATED AT 250 WORDS)

Impaired left ventricular diastolic function in acromegaly: an echocardiographic study.

To study diastolic function we digitized M-mode echocardiograms in 18 acromegalic patients (A) and compared them to an age matched control population (C). Wall thickness and left ventricular (LV) mass index are frankly increased in A (p less than 0.001). Filling pattern of the LV shows in A a prolongation of the isovolumic relaxation period (IRP) (p less than 0.001), an increase of the percentage dimension change of LV during IRP (p less than 0.001) and a reduction of the percentage dimension change during the rapid filling period (p less than 0.01). Our results indicate that relaxation is abnormal in A; this abnormality should be interpreted as a mere consequence of LV hypertrophy.

[Cardiac involvement in Friedreich's heredo-ataxia]. / Interessamento cardiaco in corso di eredoatassia di Friedreich.

The frequency and characteristics of cardiac involvement have been evaluated in 22 patients with Friedreich's ataxia and in 10 patients with non Friedreich's ataxia (Strumpell-Lorraine 5 cases; Pierre Marie 5 cases), classified according to the severity and the lasting of neurological disease. In a high percentage (45%) of patients with Friedreich's ataxia, the results show left ventricular hypertrophy as proved echocardiographically by an increase of the interventricular septum thickness and of the posterior wall thickness. On the contrary, no patient with non Friedreich's ataxia had left ventricular hypertrophy. In the patients with Friedreich's ataxia, left ventricular hypertrophy was of concentric type in 27% of the cases and of asymmetric type in 18% of the cases; left ventricular systolic indexes were not reduced. The left ventricular end-diastolic diameter was normal in all the patients. Furthermore, in 4 patients with Friedreich's ataxia (18% of the cases) without left ventricular hypertrophy, mitral valve prolapse has been found. No correlation exists between the severity and the lasting of neurologic disease and the presence of cardiac hypertrophy. This supports the hypothesis that the cardiac abnormality is a primary expression of a genetic defect and not a secondary manifestation of spinocerebellar degeneration. It is therefore necessary to always consider a patient with Friedreich's ataxia as affected with a cardiac disease even if it is not clinically evident.

[Methods of determination of stroke volume from M-mode echocardiogram of the aortic valve and aortic root. A comparative evaluation]. / Metodi di determinazione della gettata sistolica dall'ecocardiogramma M-mode della valvola aortica e della radice aortica. Una valutazione comparativa applicata.

The purpose of this study is to evaluate four methods of determining left ventricular stroke volume (SV) from aortic valve (AV) and aortic root (AR) M-mode echocardiogram (Table I, formulas 1-4); secondly, to study relations between echocardiographic aortic variables and SV. We studied 20 patients (Pts) in our Coronary Unit, 14 men and 6 women; their ages ranged from 38 to 76 (mean 53.4) years. Seventeen Pts had acute myocardial infarction; two Pts had previous myocardial infarction and heart failure; one Pt had dilated cardiomyopathy and heart failure. Three out of the twenty Pts, had mitral insufficiency (Table II, clinical and hemodynamic data). Patients were studied with high quality M-mode echocardiography. Immediately after the examination repeated measurements of cardiac output by thermodilution technique (TD) were carried out, and values of SV calculated (SV-TD). Twenty-five complete procedures were accomplished. The formulas were applied to every patient's echocardiographic data, and results (SV-ECHO) compared with SV-TD (Table III). Echocardiographic variables, whether single or multiple (terms), were also studied with regard to their relation with SV-TD (Table IV). Mean +/- SD value of SV-TD of the study group was 60.3 +/- 24.7 ml; range 22.7 to 108 ml. Mean +/- SD values of SV-ECHO were as follows: Yeh's formula, based on squared mean AV opening and LVET, 56 +/- 22.6 (ml), r = 0.8278, SEE 12.98; Jacobs' formula, based on aortic box planimetry, 68 +/- 32.5 (ml), r = 0.7129, SEE 23.31.(ABSTRACT TRUNCATED AT 250 WORDS)