Biomedical subjects

C Benvenuti

Publications and source records attributed to C Benvenuti.

At least 73 records · Page 4Linked to original sources

PubMed1992

Pharmacokinetics of two oral liquid formulations of oxatomide in children.

A study on the pharmacokinetics of two suspensions of oxatomide at the concentrations of 25 and 2.5 mg/ml was carried out on 12 children (7M, 5F) with a mean age of 9 years and weight of 29 kg. The plasmatic concentration peak, the time to reach the peak and the area under the curve displayed no significant differences between the two formulations. The maximum concentrations and the peak time of oxatomide in children are similar to those observed in adults.

Administration, Oral↗

PubMed1992

[Can solid state Holter monitoring replace endomyocardial biopsy in patients with heart transplantation?].

Acute cardiac graft rejection after transplantation, the diagnosis of which is based on the findings of endomyocardial biopsy, is associated with a reduction in coronary reserve due to abnormalities of the microcirculation. But this reduction in coronary reserve cause silent myocardial ischaemia (SMI)? In order to assess the frequency of SMI and ventricular arrhythmias during rejection, 53 consecutive Holter recordings were performed in 32 patients (28 men, 4 women, average age 47 +/- 11 years) 11 months after transplantation and within 24 hours of endomyocardial biopsy. The recorder which was used (Monitor One TC) analysed the ST segment in 2 leads in real time: ST segment depression of more than 1 mm lasting over 40 ms, 0.08 s after the J point were considered to be diagnostic of myocardial ischaemia. Although the frequency of SMI is low and not specific for cardiac rejection, its duration was twice as long (80 mn vs 38 mn) in this condition. On the other hand, ventricular arrhythmias are common in cardiac rejection and correlated with its severity according to Billingham's classification (VES p = 0.045; doublets p = 0.035; non-sustained VT p = 0.006).

Adolescent↗

PubMed1992

[Cost and efficacy of therapeutic strategies in candidates for heart transplantation as salvage therapy].

A study of the real cost, the cost-effectiveness of treatment was performed in 31 cases of cardiogenic shock referred for cardiac transplantation, treated in a flexible therapeutic protocol associating implantation of an expensive mechanical circulatory support system (mechanical bridge) or treatment by drugs alone (pharmacological bridge) depending on the efficacy of IV enoximone. The average patient cost was 238,386 French Francs, ranging from 440,353 FF in patients receiving the mechanical bridge to 199,296 FF in those receiving the pharmacological bridge. The cost-effectiveness ratio expressed either as cost per patient surviving the different stages of the disease or as cost of obtaining an additional day of survival at the same intervals was twice as favourable in the group receiving the pharmacological treatment. This study suggests that IV enoximone and strict selection procedures for candidates for the more expensive option should help bring together the interest of the individual patient and of society as a whole.

Adult↗

PubMed1992

Prognostic value of cardiac metaiodobenzylguanidine imaging in patients with heart failure.

The prognostic value of 123I-metaiodobenzylguanidine (MIBG) imaging was compared with that of other noninvasive cardiac imaging indices in ninety patients (mean age = 52 +/- 7 yr) suffering from either ischemic (n = 24) or idiopathic (n = 66) cardiomyopathy. Patients had different measurements taken: cardiac MIBG uptake, radionuclide left ventricular ejection fraction, x-ray cardiothoracic ratio and echographic M-Mode data. Cardiac MIBG uptake was assessed as the heart-to-mediastinum activity ratio measured on the chest anterior view image obtained 4 hr after intravenous injection. The patients then had follow-up for 1-27 mo, at which time 10 patients had transplants, 22 had died and 58 were still alive. Data from patients with transplants were not used in the analysis, in which multivariate stepwise regression discriminant analysis showed that cardiac MIBG uptake was more potent to predict survival than other indices: H/M (p less than 0.0001), x-ray cardiothoracic ratio (p = 0.0017), echographic end-diastolic diameter (p = 0.0264) and radionuclide left ventricular ejection fraction (p = 0.0301). Moreover, multivariate life table analysis showed that cardiac MIBG uptake was also the best predictor for life duration: H/M (p = 0.0001), radionuclide left ventricular ejection fraction (p = 0.0098) and x-ray cardiothoracic ratio (p = 0.0139); echographic data were not useful. Thus, cardiac MIBG imaging may be helpful for heart transplantation decision making in patients with heart failure.

3-Iodobenzylguanidine↗

PubMed1992

[The echographic characterization of pancreatic pseudocysts].

The diagnosis of pancreatic pseudocyst is still troublesome. In 95% of cases a correct diagnostic evaluation can be achieved by means of ECT or CT scan, ERCP, NMR, EE etc.. ECT and CT scan in particular are the most specific and accurate techniques. ECT scan is currently the up-to-date method for initial diagnosis and continuous monitoring of the lesion. In fact, very interesting real-time data and exact features of the wall of the cysts may be obtained by ECT scanning also suggesting the best therapeutic choice.

Acute Disease↗

PubMed1991

[Coronary vascular reserve in heart transplantation. Normalization after therapy for rejection].

Acute rejection is associated with severe impairment of coronary reserve in heart transplants. To evaluate the effects of rejection therapy, coronary reserve was assessed in 6 patients before and after treatment of an acute episode of rejection. Coronary reserve was significantly enhanced after rejection therapy (4.7 +/- 0.8, vs 2.3 +/- 0.5, P less than 0.001) and was not significantly different from that of transplanted patients without rejection (5.4 +/- 0.8). This study provides evidence that alterations of coronary reserve due to acute rejection are reversible after treatment of the rejection episode.

Acute Disease↗

PubMed1991

[Neuroendocrine adaptations in chronic congestive heart failure].

Chronic congestive heart failure is typically accompanied by an abnormal production of vasoconstrictor antinatriuretic hormones and vasodilator natriuretic hormones. Decompensation occurs when the former prevail over the latter. These neuroendocrine abnormalities are increasingly taken into account to determine the prognosis and to decide on the best therapeutic approach in individual patients with chronic heart failure.

Adaptation, Physiological↗

PubMed1991

Recombinant alpha interferon in metastatic renal cell carcinoma. A cooperative phase II study.

A total of 61 evaluable patients with advanced renal cell carcinoma have been treated with 3 x 10(6) IU per square meter of body surface with recombinant alpha 2b interferon three times a week within a Cooperative Phase II Study. Toxic death for terminal renal failure occurred in 1 patient (1.63%), and toxicities greater than WHO grade 2 were present in 10 cases (16%). The overall response rate after six months of treatment was 13.1% (partial response 4, minor response 4). Two complete responses were obtained at nine and fifteen months (3.3%). Long-lasting stabilization of disease was 13.1 percent.

Adult↗

PubMed1991

Perforin and granzyme B as markers for acute rejection in heart transplantation.

Histological analysis of endomyocardial biopsies (EMB) is regarded as the most satisfactory technique for monitoring crisis of rejection in heart transplanted patients. In this study, 42 biopsies from 14 patients who underwent heart transplantation were examined. Three patients did not present any rejection crisis at the date of the biopsy analysis, six were examined during an early rejection crisis (day 7-70 post-graft), and five were examined during a late rejection crisis (day 74-960 post-graft). Since granzyme B and perforin are proteins associated with cell lysis histological grading and cell phenotype analysis, in situ hybridization using granzyme B and perforin [35S]RNA probes was performed on 30 EMB to characterize the cytolytic activation of heart infiltrating cells. Our data suggest that granzyme B and perforin could be used as predictive markers for acute rejection in patients with early rejection crisis. Their detection might be an indication to administrate corticoids to resolve an acute rejection crisis. In contrast, their absence in patients with late rejection crisis appears as a good prognostic factor for the outcome of rejection and raises the question of the necessity to treat such patients with additional corticoid treatment.

Biomarkers↗

PubMed1991

Hemodynamic response to intracoronary infusion of atrial natriuretic factor in patients with normal or altered left ventricular function.

To assess the effects of atrial natriuretic factor (ANF) on cardiac function, synthetic human ANF was infused directly into the left main coronary artery of eight patients with congestive heart failure (CHF) and six subjects with normal left ventricular (LV) function (controls) who underwent cardiac catheterization. ANF infusion at the incremental rates of 60, 125, 400, and 800 ng/min induced a dose-related increase in plasma ANF concentrations in the coronary sinus, from 1,223 +/- 590 to 3,923 +/- 1,123 pg/ml in patients with CHF (p less than 0.01) and from 1,041 +/- 605 to 2,710 +/- 1,741 pg/ml in controls (p less than 0.01). Peripheral plasma ANF concentrations (femoral artery) increased from 538 +/- 278 to 752 +/- 262 pg/ml (p less than 0.01) in patients with CHF and from 193 +/- 63 to 401 +/- 147 pg/ml (p less than 0.01) in controls. The increase in peripheral or coronary sinus plasma ANF concentrations did not differ between patients with CHF and controls. At the three lowest ANF infusion rates, cardiac index (CI), systemic vascular resistance (SVR), and LV contractility assessed by peak positive dP/dt remained unchanged both in patients with CHF and in controls. At the highest ANF infusion rate, CI increased from 2.18 +/- 0.53 to 2.54 +/- 0.49 L/min/m2 (p less than 0.01) and SVR decreased from 14.6 +/- 3.6 to 12.8 +/- 4.5 mm Hg.min/L (p less than 0.01) in patients with CHF. There was no associated change in heart rate (HR), mean arterial blood pressure (MAP), cardiac filling pressures, or peak positive dP/dt.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

[Percutaneous transluminal angioplasty of the common trunk during the acute phase of myocardial infarction].

The prognosis of cardiogenic shock in the acute phase of myocardial infarction has been transformed since the introduction of techniques of myocardial revascularisation. We report the case of a patient in cardiogenic shock after a large anterior myocardial infarct in whom failure of early thrombolytic therapy led to referral for emergency percutaneous transluminal coronary angioplasty. The success of the procedure on the patient's haemodynamic condition was life-saving. The originality of this case resides in the fact that revascularisation concerned the left main coronary stem.

Angioplasty, Balloon, Coronary↗

PubMed1991

[Heart transplantation in acute myocardial infarction].

Ten patients with cardiogenic shock after acute myocardial infarction were referred to the University Hospital Henri Mondor as candidates for cardiac transplantation. The period before transplantation was bridged by maximal pharmacological support including sympathomimetic and phosphodiesterase inhibitor inotropic agents and, in non-responders, by mechanical ventricular assist devices (1 case) or artificial hearts (2 cases). The 7 patients who improved with optimal pharmacological support alone had a good initial course. However, only two of these patients were finally transplanted, three died suddenly either in the intensive care unit or after withdrawal of intravenous drugs and hospital discharge. One patient remained well and after coronary bypass surgery, enjoys good quality life. One patient was found secondarily to be a poor candidate for transplantation and died shortly after. The outcome of 2 of the 3 patients who did not respond to pharmacological treatment and who required mechanical support was spectacularly good and enabled successful cardiac transplantation. Our experience underlines the numerous difficulties of different natures of cardiac transplantation in this indication, the value and risks of the new inotropic agents, and the real but limited role of heroic procedures such as the artificial heart.

Adult↗

PubMed1991

[Coronary disease in patient following heart transplantation].

Coronary artery disease is a common and particularly severe complication of cardiac transplantation because it may cause progressive destruction of the graft by acute or chronic ischemia. The ischemia is usually silent because of cardiac denervation. Cardiac failure related to graft dysfunction, asymptomatic infarction on the ECG, or sudden death, are sometimes the only signs of severe coronary disease. The prevalence of coronary lesions has been evaluated by coronary angiography at nearly 25% at 2 years and 50% at 5 years. The distribution and morphology of the lesions are characteristic: diffuse concentric, irregular and occlusive, predominantly distal stenoses, without a distal and usually without a collateral circulation. The histological features are variable: the association of medial necrosis, severe endothelial lesions and intense parietal inflammation are suggestive of acute arteriolitis, often present during acute rejection, may be related to a common pathological process. Diffuse obliterative arteriolar lesions with concentric proliferation of medial smooth muscle are the usual appearances in transplant patients who have died or been retransplanted. There is no non-invasive diagnostic method sufficiently sensitive of specific which justifies the practice of many groups of systematic annual coronary angiography in transplanted patients. The pathogenesis is poorly understood and probably multifactorial: disorders of lipid metabolism, immunological factors, the atherogenic role of Cytomegalovirus infection. The absence of an identifiable risk factor makes preventive measures difficult. The evolutive risk justifies retransplantation in selected patients, the results of which are less satisfactory but which reduces the risk of acute coronary events and sudden death.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Angiography↗

PubMed1991

Irreversible drop of systemic vascular resistances in patients implanted with a Jarvik total artificial heart.

Maintenance of the body's perfusion by a total artificial heart (TAH) may result in physiological alterations to the circulatory system. Little has been said about modifications to systemic vascular resistances (SVR) during TAH assistance. This paper reports on two patients implanted with a Jarvik - 70 cc TAH, who died after 1 and 3 days, both with an irreversible drop of SVR related to a complete loss of vascular tone but not related to sepsis. Activation of multiple cascades of inflammation, triggered by the extracorporeal circulation (ECC), is maintained during TAH support. Desperately sick patients might not be able to face the vaso-active situations created by the inflammatory response.

Adult↗

PubMed1991

Pharmacokinetics of fluocinolone acetonide in patch versus cream formulations.

The pharmacokinetics of the fluocinolone acetonide patch containing 8 mcg/cm2 and a 0.025% cream were studied in a cross-over trial in 12 healthy volunteers 6 male and 6 female mean age 24.9 years. Each subject was treated with 0.8 mg of both fluocinolone acetonide formulations for 12 h on non-consecutive days. The high performance liquid chromatography method was used to determine the plasma and urine levels of the drug. Minor fluctuations in the plasma profile after patch application were observed, even if no significant difference was found between the two formulations with regard to peak plasma concentration, time to reach peak levels, area under the concentration curve and half-life.

Administration, Topical↗

PubMed1991

Bioavailability of intranasal neostigmine: comparison with intravenous route.

The pharmacokinetics of intranasal (i.n.) neostigmine was compared with the intravenous (i.v.) route in 6 healthy volunteers with a mean age of 25.5 years and a mean weight of 65.8 kg in a crossover design. The doses used were 0.5 mg i.v. and 21.6 mg i.n. Neostigmine was determined by HPLC. The plasmatic profiles of the two routes were similar. An early peak of plasmatic concentration after i.n. administration was observed. The absolute bioequivalence of the i.n. route was ten-fold greater than the oral one.

Administration, Intranasal↗

PubMed1990

[Cardiac transplantation: indications and results].

Although many problems remain, cardiac transplantation is now associated with a 5 year survival rate of about 70 per cent which is a very acceptable therapeutic result in patients with cardiac failure and no other medical or surgical alternative. Parallel improvement in the medical management of chronic cardiac failure has prolonged survival of many patients. Transplantation should only be considered if the benefits not only in terms of survival but also in terms of quality of life, are greater than of survival but also in terms of quality of life, are greater than those of medical treatment of the cardiac disease. The indications and timing of cardiac transplantation are therefore based on a complex prognostic evaluation adapted to each individual case which may eventually need reconsideration. Satisfactory results depend on strict patient selection with respect for the surgical indications and contra-indications.

Adult↗

PubMed1990

Effect of plasma volume expansion on hemodynamics and atrial natriuretic factor release in heart-transplant recipients.

Plasma atrial natriuretic factor (ANF), plasma cyclic guanosine monophosphate (cGMP), plasma aldosterone, plasma-renin activity (PRA) and hemodynamic parameters were measured in heart-transplant recipients and control patients (chest pain syndrome) during right-sided heart catheterization under basal conditions and in response to an intravenous saline load. Basal plasma ANF and cGMP were higher in heart-transplant recipients than in control patients, whereas PRA and plasma aldosterone did not differ. The high plasma ANF levels in heart-transplant recipients did not result from high atrial pressures but appeared to be related with elevated atrial dimensions and cyclosporine-induced renal failure. During volume expansion, plasma ANF increased in control patients and remained elevated during the postinfusion period. In heart-transplant recipients, the changes in plasma ANF were less marked despite identical increases of atrial pressures. The sluggish response of plasma ANF in this group was associated in the postinfusion period with a nonreturn of the hemodynamic parameters to their basal values in contrast with what was observed in control patients.

Adult↗