PubMed Health⌕ Search

Biomedical subjects

E Pisano

Publications and source records attributed to E Pisano.

At least 19 recordsLinked to original sources
PubMed2000

First human experience with pulmonary vein isolation using a through-the-balloon circumferential ultrasound ablation system for recurrent atrial fibrillation.

BACKGROUND: Standard mapping and ablation of focal sources of atrial fibrillation are associated with very long procedure times and low efficacy. An anatomic approach to complete pulmonary vein isolation could overcome these limitations. METHODS AND RESULTS: Fifteen patients with atrial fibrillation refractory to medication underwent circumferential isolation of the pulmonary veins by using a novel catheter, with an ultrasound transducer (8-MHz) mounted near the tip, in a saline-filled balloon. Twelve atrial foci and/or atrial fibrillation triggers were identified in 9 patients (pulmonary vein locations: left upper, 3; right upper, 6; right middle, 1; right lower, 1; and left inferior, 1). In 5 patients, lesions were placed in the absence of any mapped triggers. Irrespective of trigger mapping, circumferential isolation of both upper pulmonary veins was attempted in all patients. The lower pulmonary veins were ablated when sinus rhythm activation mapping revealed evidence of a sleeve of atrial muscle in the vein. The median number of lesions per patient required to isolate 1 pulmonary vein was 4 (range, 1 to 29). After ablation, no evidence of narrowing was seen with repeat venography or follow-up computed tomography scan. After a mean follow-up of 35+/-6 weeks, 5 patients had recurrence of atrial fibrillation. Three responded to drugs that were previously ineffective, and 2 remained in atrial fibrillation. CONCLUSIONS: This novel ultrasound ablation system can successfully isolate multiple pulmonary veins. At early follow-up, this approach seems to be effective in preventing recurrent atrial fibrillation in a significant number of patients.

Adult↗
PubMed2000

Prior hrt use, ethnicity and mammographic density.

PURPOSE: Mammographic density has been strongly associated with breast cancer risk in several studies. To clarify possible pathogenic mechanisms underlying this relationship, we assessed factors affecting mammographic density in postmenopausal women.METHODS: Percent density (PD) was measured on pre-randomization mammograms from 425 participants in the Women's Health Initiative clinical trial; no women were currently using HRT. Trained observers used a previously validated computer-assisted thresholding technique to measure PD (ratio of dense areas to breast area) on craniocaudal films. Univariate relationships were assessed between PD and age, parity, education, history of HRT use, age at first birth, abortion history, alcohol use, serum cholesterol, physical activity, smoking, dietary fat intake, body-mass index (BMI), and waist-to-hip ratio (WHR). Multivariable regression was used to identify predictors of PD (log transformed), controlling for confounders.RESULTS: PD ranged from 0-60% with mean 8%. Age, gravidity, BMI, and WHR were negatively associated with PD. Mean PD in the highest tertiles of BMI and WHR was nearly half that in the lowest. Ethnicity (50% white, 28% black, and 19% Hispanic) and hysterectomy status (50% had intact uterus) were unassociated with PD. Controlling for age, BMI, WHR, smoking, hysterectomy status, prior HRT, and nulliparity, mean PD differed significantly by ethnicity, with black women having highest PD. However, the effect of prior HRT use differed by uterine status. In women with uteri intact, ethnicity, but not prior HRT use, was related to PD after controlling for age, BMI, and WHR. In hysterectomized women, ethnicity was unrelated to PD, while previous HRT was associated with lower PD.CONCLUSIONS: Gravidity, ethnicity and body shape and size are associated with mammographic density in postmenopausal women. Previous hormone use predicts lower PD, but only among hysterectomized women. This may be due to the higher frequency of oophorectomies in this group, which may lower PD and increase likelihood of HRT use. Planned analyses of entire sample of 1050 women will clarify the effect of these and other factors on density, and on density change in followup mammograms.

Journal Article↗
PubMed2000

Catheter ablation approach on the right side only for paroxysmal atrial fibrillation therapy: long-term results.

We report the long-term follow-up of a right side only catheter ablation approach for paroxysmal AF. Eighteen patients with AF refractory to drugs entered the study. Ablation was attempted in the right atrium only by creating linear lesions based on a specific design including from two to four linear lesions. Induction of AF was attempted before ablation and after placement of the lesions. A septal lesion was performed in nine patients. In ten patients atrial defibrillation thresholds (ADFTs) before ablation and following creation of the linear lesions were compared. After a mean follow-up of 22 +/- 11 months, seven patients had recurrence of AF, and another nine patients experienced atrial flutter or atrial tachycardia. Five patients remained in sinus rhythm without medications and four required the use of drugs. Three patients had sporadic AF and six were in chronic AF. The recurrence rate was similar in patients with and without the septal lesion. However, a cure with right side ablation appeared to be predicted by the presence of disorganized and earlier activity in the high right atrium and crista terminalis. Linear lesions in the right atrium were associated with a lower ADFT (pre 2.6 +/- 04 J vs post 1.7 +/- 0.6 J). In conclusion, in a small number of patients, control of AF can be obtained with a right side only approach. Certain activation patterns may identify patients suitable to this approach. No specific lesion pattern appeared more effective. Right atrial linear lesions resulted in lower ADFT.

Atrial Fibrillation↗
PubMed1999

AV node ablation and pacemaker implantation after withdrawal of effective rate-control medications for chronic atrial fibrillation: effect on quality of life and exercise performance.

We assess whether AV node ablation and pacemaker implantation after discontinuation of effective rate-control medical therapy for chronic atrial fibrillation had a positive impact on quality of life and exercise performance. To assess the possibility of a placebo effect following pacemaker implantation, the study included three groups of patients. Group 1 underwent an echocardiogram, treadmill exercise, and quality of life measurement 1 month prior to and 6 months following AV node ablation and pacemaker implantation associated with discontinuation of rate-control medications. Group 2 underwent AV node ablation and pacemaker implantation without discontinuation of antiarrhythmic rate-control drugs. Group 3 underwent pacemaker implantation without performing AV node ablation and continuing rate-control medical therapy. At the 1- and 6-month evaluation, the patients in group 1 showed a significant improvement of left ventricular ejection fraction, quality of life, and activity scores. The exercise duration and the maximal VO2 consumption, however, did not change significantly. A slight improvement of the quality of life and physical activity scores was observed in the group undergoing AV node ablation without withdrawal of medications. However, no significant changes were observed in the group receiving only the pacemaker without modification of medical therapy and with intact AV node conduction. In conclusion, in patients with chronic atrial fibrillation, discontinuation of effective rate-control medical therapy followed by AV node ablation and permanent pacing appeared to improve quality of life and activity scores despite no change in exercise duration. The improvement observed does not seem to reflect a placebo effect.

Aged↗
PubMed1999

[Timely detection of premature closure of the ductus arteriosus in a full-term fetus. Important role of fetal echocardiography].

Patency of the ductus arteriosus (DA) is maintained during gestation by locally produced and circulating prostaglandins (PGE's). As gestation proceeds, the ductus becomes less sensitive to dilating prostaglandins and more sensitive to constricting factors such as PGE's synthetase inhibitors. This case report describes a fetus at term (38 weeks) with signs of severe right ventricular failure due to constriction of DA. Maternal history documented 5 day assumption of a non-steroid antiinflammatory agent to relieve skeletal-muscle pain. Careful echocardiogram ruled out a structural heart disease, such as coarctation of the aorta. A gradient of 41 mmHg across the ductus was recorded. A cesarean section delivery was immediately undertaken. The 3.5 kg newborn delivered appeared to be in good health, with Apgar score of 8/9 at 1 and 5'. There were no signs of congestive heart failure and mild respiratory distress. An echocardiogram showed a dilated, well contractile right ventricle, with a pressure of 50 mmHg. DA was already closed. The fetal echocardiogram was the most relevant investigation in the decision-making process of this case treatment. Any different evaluation of this fetal heart, delaying the delivery would have very seriously compromised the survival of the fetus. Fetal echocardiography is the most important diagnostic tool in the evaluation of the fetal heart; non steroid antiinflammatory drugs to mother at term should be avoided or given with close echocardiographic assessment of DA patency.

Adult↗
PubMed1997

Diffraction enhanced x-ray imaging.

Diffraction enhanced imaging is a new x-ray radiographic imaging modality using monochromatic x-rays from a synchrotron which produces images of thick absorbing objects that are almost completely free of scatter. They show dramatically improved contrast over standard imaging applied to the same phantom. The contrast is based not only on attenuation but also the refraction and diffraction properties of the sample. This imaging method may improve image quality for medical applications, industrial radiography for non-destructive testing and x-ray computed tomography.

Biophysical Phenomena↗
PubMed1996

Ribosomal RNA location in the Antarctic fish Champsocephalus gunnari (Notothenioidei, Channichthyidae) using banding and fluorescence in situ hybridization.

A biotinylated 28S rDNA probe was prepared from the genomic DNA of the Antarctic ice-fish Champsocephalus gunnari and hybridized to metaphase chromosomes of the same species by fluorescence in situ hybridization (FISH). The hybridization signal appeared over the whole heterochromatic arm of the submetacentric chromosomes bearing the nucleolar organizer regions. The results of rDNA/FISH are compared with those coming from classical cytogenetic (C, Q, Ag-NOR, chromomycin A3) banding techniques. The in situ detection of a specific DNA sequence offers a new more precise perspective for understanding the evolving process in chromosomes of Antarctic fish and will provide an interesting contribution to comparative cytogenetics of lower vertebrates.

Animals↗
PubMed1996

Safety of nurse-administered deep sedation for defibrillator implantation in the electrophysiology laboratory.

UNLABELLED: Implantation of implantable cardioverter defibrillators (ICDs) in the electrophysiology (EP) laboratory has been shown to be safe. However, general endotracheal anesthesia and/or administration of sedatives is mostly performed by anesthesiologists. In 53 patients undergoing ICD implantation in the EP laboratory, we prospectively assessed whether deep sedation without endotracheal intubation can be administered by nursing personnel under medical supervision. The mean patient age was 67 +/- 7 years, and the mean ejection fraction was 32 +/- 8%. All ICDs were placed in the abdomen requiring lead tunneling. Patients were monitored with pulse oximetry and noninvasive blood pressure recordings. The level of consciousness and vital signs were evaluated at 5-minute intervals. Deep sedation was induced with phenergan and midazolam and maintained with either meperidine or fentanyl. The mean doses given were as follows: phenergan 0.33 +/- 0.15 mg/kg, midazolam 0.05 +/- 0.03 mg/kg, meperidine 0.46 +/- 0.10 mg/kg per hour, and fentanyl 1.94 +/- 0.71 micrograms/kg per hour. None of the patients required intubation during or after the procedure. No death occurred and no patient had any recollection of the procedure. In three patients, O2 desaturation was easily managed by transient reversion of the effects of meperidine or fentanyl with naloxone. No patient experienced prolonged hospitalization after the implant (mean 2.4 +/- 0.5 days). IN CONCLUSION: (1) adequate sedation for ICD implantation and testing can be administered safely by nursing staff in the EP lab; (2) optimum sedation protocols should include drugs easy to reverse in case of excessive respiratory depression; and (3) this may represent a more cost-effective approach to ICD implantation.

Aged↗
PubMed1996

Mammographic phantom studies with synchrotron radiation.

PURPOSE: To explore the potential improvement in image contrast for breast imaging with use of monoenergetic photons. MATERIALS AND METHODS: The x-ray energy available from the National Synchrotron Light Source is from 5 to over 50 keV. A specific energy is selected with a tunable crystal monochromator. The object is scanned with a narrow beam of 80.0 x 0.5 mm. Mammography phantoms were imaged with plate and film as the imaging detectors. Phantom images were obtained at 16-24 keV and compared with images obtained with a conventional mammographic unit. RESULTS: Preliminary findings indicate improved image contrast of the monoenergetic images compared with that obtained from the conventional x-ray source, particularly at 18 keV and below. CONCLUSION: Pilot results are encouraging, and the authors presently continue to explore monoenergetic photon imaging with improved instrumentation, scatter rejection, and use of tissue samples.

Breast Neoplasms↗
PubMed1994

Abdominal aortic hypoplasia: clinical and technical considerations.

Hypoplasia of the distal abdominal aorta, first described by Quain in 1847, is rarely associated with atherosclerotic occlusive disease. The condition usually occurs early in life; the principal clinical features are hypertension and arterial insufficiency of the lower extremities which is often well tolerated. Some 20 patients had operations for abdominal aortic hypoplasia; 16 underwent prosthetic reconstruction and four had aortoiliac endarterectomy with angioplasty. Reconstructive techniques were influenced by narrow renal arteries and by the presence of extensive atheroma. The long-term prognosis is often poor, especially in patients with extensive disease.

Adult↗
PubMed1994

Late occlusion of aortofemoral bypass graft: surgical treatment.

Surgical treatment for graft thrombosis is often difficult and its outcome is complicated by a high incidence of rethrombosis. The records of 803 patients (1261 limbs) treated with aortofemoral bypass graft for peripheral vascular disease were reviewed. Among these, 71 patients (63 men and eight women with a mean age of 60.2 years) needed an overall number of 125 reoperations. The mean follow-up was 6.3 years. Smoking was significantly higher in these patients compared with those who were not reoperated on. Intimal hyperplasia was the most common lesion responsible for graft thrombosis. Before 'redo' surgery 20 patients with recent thrombosis received thrombolytic treatment; one was subsequently treated with percutaneous transluminal angioplasty and the others underwent reoperation. The best patency rates were achieved with reconstruction of the distal anastomosis with a graft interposition or with a patch angioplasty. Isolated thrombectomy was complicated by early rethrombosis in 53.3% of cases. The overall amputation rate was 14%, the operative mortality rate 5.6%, and the incidence of complications 16.8%. At follow-up a cumulative secondary patency rate of 81.7% at 5 years (74.5% at 10 years), a limb salvage rate of 80.5%, and a survival rate of 89.2% at 10 years were recorded. It is concluded that the only indications for redo surgery following graft thrombosis are severe limb ischaemia or disabling claudication.

Adult↗
PubMed1994

Ischemia-reperfusion syndrome: an alternative experimental model.

OBJECTIVE: To design an alternative experimental model of ischemia-reperfusion syndrome. Our model mimics the clinical pattern of the syndrome and also assesses the efficacy of therapeutical protocols. EXPERIMENTAL DESIGN: Ischemia was induced under general anaesthesia in the posterior limbs of 10 sheep by occluding the aorta and vena cava by means of two-way balloon catheters. Ischemia was stopped after 4 hours and blood and histologic parameters determined in the first three hours of revascularization. The animals were divided into three groups: a group of 3 sheep in which a sham operation was performed; a control group (5) to assess the efficacy of induced ischemia; the third group (5) to determine the effect of antioxidant and membrane protective drugs to assess the reliability of the model to study the ischemia-reperfusion syndrome. RESULTS: At the end of ischemia, skin temperature was decreased (p < 0.04) both in control and treated groups, pH decreased significantly soon after reperfusion in the control group (p < 0.04). Reperfusion in control sheep, compared with treated animals, was followed by a significant increase in CPK blood levels (p < 0.009), related to marked muscle damage, in particular after reperfusion. Tissue damage detected at TEM was less severe in treated animals. CONCLUSIONS: This model is an effective experimental strategy and a means of assessing preventive treatment.

Animals↗
PubMed1993

Prevention of reperfusion syndrome in acute muscular ischaemia with free radical scavengers and membrane-protecting compounds: an experimental study.

The prevention of oxidant-induced damage following reperfusion was experimentally evaluated. Two pharmacological regimens containing different combinations of antioxidant factors and membrane-stabilizing compounds, such as alpha-tocopherol (vitamin E), methionine, dexamethasone, mannitol and cysteine, were administered. The reduced/oxidized glutathione (GSH/GSSG) ratio in muscle was used to evaluate oxidative stress. Ischaemia was induced by occluding the aorta and the inferior vena cava with an irrigation-occlusion catheter. After 4 h of ischaemia, five sheep were reperfused without any treatment (control group) and five treated with an endoaortic bolus administered at declamping (treatment 1). In five other sheep, treatment started during ischaemia (treatment 2). Ischaemia and, in particular, reperfusion significantly reduced the muscle GSH content, compared with the basal value in the control group; thus the GSH/GSSG ratio decreased significantly in the control group from 10.5(2.2) (mean(s.e.) basal value) to 0.687(0.3) at reperfusion (P < 0.009). Both treatments 1 and 2 significantly prevented a reduction in GSH content induced by reperfusion following ischaemia; the GSH/GSSG ratio (10.5(2.2) basal value) increased to 19.67(4.6) with reperfusion in the treatment group 1, mainly because of a lower decrease of GSH and a lower level of GSSG while it did not change in treatment group 2 (10.7(5.0)). Levels of creatine phosphokinase did not change in the treated groups, although they increased significantly in the control group (P < 0.006). Although oxidative stress is not the only cause of damage in revascularization, this study confirms the protective ability of treatment with free radical scavengers and membrane-stabilizing compounds.

Animals↗
PubMed1993

Natural history of patients with carotid stenosis waiting for surgical treatment.

BACKGROUND AND PURPOSE: The natural history of carotid lesions has generally been evaluated in anedoctal series or in clinical trials. The purpose of this study was to evaluate clinical and pathological modifications linked to an increasing waiting list in our region and the related medico-legal implications. METHODS: Neurological symptoms that occurred during the waiting period were evaluated in 282 out of 491 patients placed on the waiting list for a carotid stenosis less than 80% or without an unstable plaque. The other 202 patients cancelled their booking. Progression of carotid disease was evaluated by duplex scanning in 116 patients who had a duplex evaluation in our Department both at booking and at the time of operation. RESULTS: The incidence of stroke in a mean waiting period of 8.9 months was 2.6% in symptomatic patients and 1.5% in asymptomatic, respectively; 39 (13.8%) patients experienced an ipsilateral TIA and 4.2% a carotid thrombosis (25% of which symptomatic). The crude mortality-rate was 2.4% with a 1% of related deaths. The cumulative actuarial hard end points rate (stroke, carotid thrombosis and related death) was 7.8% at 12 months and 19.8% at 18 months. CONCLUSIONS: This study gives us data about the natural history of carotid stenosis in our country. The high morbidity and mortality-rate related to this lesion and particularly their occurrence within the first 3 months stress the urgency of treatment, and of the planning of specialized Departments in relation to the real incidence of the pathology in order to avoid medico-legal consequences.

Aged↗
PubMed1992

Local haemofiltration with free radical scavenger treatment during revascularisation of severe muscular ischaemia induced in sheep limbs.

Many treatments have been proposed for the prevention of the revascularisation syndrome following embolectomy or thrombectomy in patients with severe ischaemia. These include the administration of diuretics, bicarbonate, buffer solutions, free radical scavengers, washing out the venous blood from the ischaemic leg, or systemic dialysis. The aim of our study was to investigate the effect of combining haemofiltration with a treatment using compound oxy-radical scavengers in order to prevent or to reduce the appearance of the revascularisation syndrome. The study was performed on 13 sheep. Eight animals underwent 4 h of aortic and vena cava occlusion using irrigation-occlusion catheters, followed by normal reperfusion (control group). Five sheep underwent the same period of ischaemia, followed by 1 h of local haemofiltration and re-oxygenation and 2 h of normal revascularisation. The priming solution for the ECC circuit consisted of 500 ml of 20% mannitol and 500 ml of 18/1000 HCO3- contained: superoxide dismutase (150,000 I.U.), methylprednisolone, 1 g, and heparin, 10,000 I.U. After the 3rd h of ischaemia, 2.1 g of acetate alpha-tocopherol (30 mg kg-1) were injected i.m. The treatment produced good protection against oxidative stress, shown by an increase in the glutathione ratio (GSH/GSSG), and reduced muscular damage, confirmed by a moderate increase in creatine phosphokinase (CPK) levels (significantly higher in the control group). Diuresis was significantly higher in the treated group, and the acid-basic and potassium balance returned to normal more rapidly. Our data suggest that this combined treatment could be effective in the prevention of the ischaemia-reperfusion syndrome.

Animals↗
PubMed1984

Adrenal and testicular function in boys affected by thalassemia.

The adrenal androgen secretion and testicular function were studied in 6 thalassemic boys aged between 16 and 20 years. Six normal boys of the same age and 6 at the same pubertal stage (P1 according to Tanner) were also studied as controls. Plasma testosterone levels were found significantly lower (p less than 0.001) in the thalassemic boys (0.8 +/- 0.1 ng/ml) than in healthy boys of the same age (3.4 +/- 1.01 ng/ml), but within the range of the healthy boys at the same pubertal stage (0.69 +/- 0.1 ng/ml). DHA-S, a marker of adrenal maturation, showed a similar pattern. The hCG test showed a significant (p less than 0.001) testosterone response in all 3 groups. The response of thalassemic boys (1.5 +/- 0.18 ng/ml) was similar to that of normal boys at stage P1 (1.8 +/- 0.31 ng/ml), but significantly lower (p less than 0.001) than the group of normal boys of the same age (12.5 +/- 3.2 ng/ml). The impaired adrenal and testicular activity is probably due to iron deposits in the endocrine glands.

Adolescent↗