Biomedical subjects

A Scialdone

Publications and source records attributed to A Scialdone.

At least 19 recordsLinked to original sources

PubMed2001

Atrial natriuretic factor and mitral valve prolapse syndrome.

Mitral valve prolapse (MVP), is the most frequent valvulopathy, although it is difficult to evaluate its incidence since this pathology is often asymptomatic. However, in some patients a rich variety of symptoms such as chest pain, dyspnea, palpitations, syncope, dizziness, panic attacks and autonomic dysfunctions have been found. The pathogenesis of these symptoms, incompletely understood, appears to be multifactorial, related to altered autonomic function, adrenergic responsiveness and to combinations of these factors. In patients with MVP a variety of neuroendocrine anomalies has been found: high epinephrine and norepinephrine plasma levels, altered rennin-angiotensin-aldosteron (RAA) response to volume depletion and orthostatic stimulation, and high plasma levels of atrial natriuretic factor (ANF) especially in hypovolaemic individuals. The role of ANF could be important in the genesis of MVP syndrome, it could contribute to determine: the imbalance between the sympathetic and parasympathetic system, the altered RAA response to orthostatic stimulus, the volemic and venous flow reductions (with a direct action, other than diuretic and natriuretic action). Factors that can determine ANF secretion abnormality in MVP could be: 1) Mitral regurgitation; 2) increased heart rate and the high incidence, in MVP syndrome, of arrhythmias; 3) central nervous system neuroendocrine imbalance; 4) increased catecholamines secretion.

Atrial Natriuretic Factor↗

PubMed2000

[TNF alpha and heart failure].

Tumor necrosis factor alpha (TNF alpha) is a cytokine with proinflammatory properties which produces negative inotropic effects on the heart. It is produced in a variety of conditions such as septic shock, acute myocarditis, reperfusion injury, and congestive hear failure (CHF). This production is probably due to activation of immune elements localized in the heart or periphery, or both. TNF alpha acts by binding to two specific receptors: TNF-R1 and TNF-R2. These two proteins have different effects. TNF-R1 has cytotoxic and antiviral activity, induces fibroblast proliferation, and mediates apoptosis. TNF-R2 is involved in septic shock and in lymphocyte proliferation. They both have negative inotropic effect on the heart. It has been showed that these receptors are down-regulated in congestive heart failure, while their soluble forms (sTNF-R1 and sTNF-R2) increase with the severity of symptoms. However the significance of this increase is still unclear. The role of Fas, a receptor protein that induces apoptosis, is also examined. Fas and its ligand have homologies respectively with TNF alpha and TNF-R. Also the soluble form of Fas (sFas) increases in relation to heart failure and is related to soluble forms of the similar receptor family, therefore it is possible that the same stimuli lead the three receptors to act together. SFas, as well as sTNF receptors, may play an important role in CHF.

Heart Failure↗

PubMed1998

Electrophysiologic significance of leftward QRS axis deviation in bifascicular and trifascicular blocks.

BACKGROUND: Intraventricular conduction disturbances determine complete impairment of impulse propagation along the right or left bundle branch or the two left fascicles. HYPOTHESIS: This study was undertaken to investigate the electrophysiologic significance of QRS axis (QRSA) orientation in bifascicular and trifascicular blocks. METHODS: A group of 76 subjects, 43 with right bundle-branch block (RBBB) and left anterior hemiblock (LAH) (Group A), and 33 with left bundle-branch block (LBBB) (Group B), was submitted to electrophysiologic evaluation. RESULTS: In Group A, QRSA was inversely related only to intraventricular conduction, while in Group B, QRSA inversely related to infrahisal conduction times. A value of < -60 degrees was considered the cut-off point for determining subjects with a considerable leftward QRSA deviation. Of the 27 Group A patients with a QRSA < -60 degrees, 38.5% developed an infrahisal second-degree atrioventricular (AV) block during incremental atrial stimulation (IAS) in comparison with 11.1% of those with QRSA > -60 degrees. Of the 9 Group B patients with a QRSA < -60 degrees, 44.4% exhibited severe impairment of infrahisal conduction at baseline and 66.6% developed an infrahisal second-degree AV block during IAS, whereas among the remaining 24 with a QRSA > -60 degrees, in only 8.3% were both infrahisal (HV1 and HV2) intervals dangerously prolonged, and 23.8% encountered an infrahisal second-degree AV block during IAS. In Group A, atrioventricular conduction time > 200 ms exhibited a better predictive accuracy than QRSA < -60 degrees for the development of an infrahisal second-degree AV block during IAS, whereas the latter appeared the best noninvasive predictor in Group B with a slightly lesser predictive accuracy than HV > 80 ms. CONCLUSION: The degree of leftward QRSA deviation seems to reflect the entity of intraventricular conduction delay in patients with RBBB + LAH, while it appears to be directly related to infrahisal conduction prolongation in those with LBBB.

Aged↗

PubMed1997

A motorized hand piece for injectable lenses.

Foldable lenses represent a major breakthrough in the effort to achieve ever smaller incisions. The plate-haptic or "taco-style" lenses are folded and implanted by a device called an injector. Although customized for each manufacturer's lens, the injectors all have a common design principle: the intraocular lens (IOL) is folded within a funnel-like structure of the tip and is advanced by a plunger that pushes and delivers the lens. To maintain optimal hand stabilization and injector management, both hands are usually required. This does not leave a hand to help with IOL positioning. To improve handling, a simple, mechanized system has been created for a new injector system that allows the delivery of the plate-haptic lens with one hand, in a pen-like fashion.

Equipment Design↗

PubMed1997

[Electrophysiological analysis of atrioventricular and intraventricular conduction in bi- and tri-fascicular blocks].

We have evaluated, at baseline and during incremental atrial pacing (AP), intracardiac conduction features of 53 patients with electrocardiographic diagnosis of bifascicular or trifascicular block, free from any pharmacological treatment potentially able to affect atrioventricular (AV) conduction system properties. The patients have been subdivided in the following groups: group A (13 patients), with LBBB and a PQ interval > or = 200 msec; group B (14 patients), with RBBB, LAH with a PQ interval > or = 200 msec; group C (8 patients), with LBBB and a PQ < 200 msec; group D (15 patients), with RBBB, LAH and a PQ < 200 msec; group E (3 patients), with RBBB, LPH and a PQ < 200 msec. In group A, 31% presented a long AH interval (> 140 msec), while 85% showed an increased infra-his conduction time (HV > 55 msec). During AP, only 38.5% maintained a 1:1 AV conduction ratio up to 140 bpm, while 30.8% developed an infra-his Mobitz 2 2nd degree AV block. 15.4% an infrahis 2:1 2nd degree AV block, 15.4% an AV nodal Mobitz 2 2nd degree AV block. In group B, 64% and 29% exhibited respectively an AV nodal and an infrahis conduction delay. During AP, 57.1% maintained a 1:1 AV conduction ratio up to 140 bpm, 14.3% developed an AV nodal Mobitz 1 2nd degree AV block, 14.3% an infrahis Mobitz 1 2nd degree AV block, 7.1% an AV nodal 2:1 2nd degree AV block, 7.1% an infrahis Mobitz 2 2nd degree AV block. In group C, no patient manifested a prolonged AH interval, while 50% exhibited a HV > 55 msec. 62.5% maintained a 1:1 AV conduction ratio up to 140 bpm, 25% developed an AV nodal Mobitz 1 2nd degree AV block and 12.5% an infrahis 2:1 2nd degree AV block. In group D, no patient showed an increased AH interval and only 13% presented a HV interval exceeding 55 msec. During AP, 86.7% maintained a 1:1 AV conduction ratio up to 140 bpm, 6.6% developed an AV nodal Mobitz 1 2nd degree AV block, 6.6% an infrahis 2:1 2nd degree AV block. In group E, no patient showed a prolonged AH interval, while 2/3 (66.6%) exhibited an infrahis conduction delay. During AP, 100% developed an infrahis 2:1 2nd degree AV block. Considering all patients with LBBB (groups A+C) and with RBBB+LAH (groups B+D), no differences were found in terms of PQ, PA and AH intervals, even though, concerning patients with a long PQ (group A vs group B), AH interval resulted significantly longer in patients with RBBB+LAH (121.85 +/- 36.4 msec vs 163.29 +/- 55.96 msec, p = 0.031). Infrahis conduction, independently from the measurement adopted (HVI interval: from the beginning of the His to the onset of the ventricular electrogram recorded at the His region; HV2 interval: from the beginning of the His to the onset of the surface QRS), resulted more compromised in patients with LBBB than in patients with RBBB+LAH (HVI: 75.24 +/- 40.23 msec vs 50.79 +/- 25.16 msec, p = 0.011; HV2: 77.24 +/- 38.12 msec vs 53.92 +/- 29.3 msec, p = 0.015). Such a difference became even more significant when comparing the percentage of patients with a prolonged HV interval (average value > 55 msec) in the above mentioned groups: 71.4% in case of LBBB, 20.7% in case of RBBB+LAH (p < 0.001). Regarding intraventricular conduction (IV), no statistically significant differences were found. In patients with RBBB+LAH, IV was not related to infrahis conduction time and PQ interval appeared more related to AH (r = 0.838, p < 0.001) than to HV (PQ-HV1: r = 0.381, p = 0.041, PQ-HV2: r = 0.474, p = 0.009). Conversely, in patients with LBBB infrahis and IV conduction appeared linearly related (HVI-V: r = 0.416, p = 0.06; HV2-V: r = 0.445, p = 0.043). As for PQ interval, it resulted more closely related to infrahis conduction (PQ-HVI: r = 0.626, p = 0.002; PQ-HV2: r = 0.674, p < 0.001), than to AH (r = 0.533, p = 0.013). In conclusion, infrahis conduction resulted more impaired in patients with LBBB. In this group, differently from patients with RBBB+LAH, infrahis conduction seems to affect the degree of IV conduction delay. (ABST

Aged↗

PubMed1996

[Sotalol, propafenone, and flecainide: compared multiparametric analysis of ventricular repolarization in subjects without organic cardiopathy].

Antiarrhythmic drugs are known to affect depolarization and repolarization time in a different fashion. The aim of the present study was to compare the effects of sotalol, flecainide and propafenone on some common (mean QT and QTc, mean JT and JTc), or uncommon (QTc dispersion, T-peak to T-end interval-Tp-Te) electrocardiographic parameters in order to evaluate the effects of these antiarrhythmic drugs on repolarization time. QTc dispersion, defined as the difference between maximum and minimum QTc calculated from the standard 12 ECG leads, and the average Tp-Te interval, reflect regional variation in ventricular repolarization. We have analyzed retrospectively the standard 12-lead electrocardiograms of 28 patients (15 females and 13 males, age 36.11 +/- 16 years, range 11-67 years), recorded in the free-drug state and at the steady state after oral treatment with sotalol (160 mg/ die), flecainide (200 mg/die) and propafenone (450 mg/die). These drugs were prescribed, separately, for the treatment of patients with supraventricular tachycardia without underlying structural heart disease. Sotalol treatment prolongs ventricular repolarization times (QT, p = 0.0001; JT, p = 0.0001 and JTc, p = 0.0001) in an homogeneous fashion, as showed by the significant decrease in QTc dispersion (p = 0.026) and Tp-Te interval (p = 0.011). On the contrary, flecainide treatment is associated with an increase in QTc dispersion (p = 0.039) and Tp-Te interval (p = 0.0001), mean QT (p = 0.0001), QTc (p = 0.0001) and QRS (p = 0.0001), with no significant changes in JT and JTc (NS). Propafenone treatment does not affect repolarization time indexes, affecting only depolarization time as expressed by an increase in QRS (p = 0.046).

Adolescent↗

PubMed1993

[ST elevation during ergometric test: correlation with coronary angiography].

BACKGROUND: ST elevation during ergometric stress test (EST) is relatively rare. Its prevalence depends upon the tested population but occurs more frequently in patients who have had myocardial infarction or variant angina. This phenomenon is very rare in patients with typical exertional angina and its pathogenesis is still unclear. MATERIAL AND METHODS: We studied a group of 75 consecutive patients with exertional angina who underwent EST and coronary angiography. A symptom limited EST was performed in the upright position on a cycloergometer with load increases of 25 watts every 3 minutes and 12 leads were monitored during all test. Coronary angiography was performed according to Judkins technique. From these patients, according to Froelicher's criteria, a group of 49 patients (age 32-68, mean 51.6 years), without myocardial infarction and/or left ventricular asynergy, was selected. RESULTS: All patients had a coronary artery disease (16 patients with 3 vessels, 11 patients with 2 vessels and 22 patients with 1 vessel disease). The EST was positive for ST depression in 31 patients (63.3%) and for ST elevation in 5 patients (10.1%), while 13 patients (26.6%) had a non diagnostic EST. The ST elevation occurs in V1-V2 and it was associated in all cases with a stenosis in the left anterior descending (LAD) artery. Therefore we divided the 19 patients with LAD stenosis into two subgroups: subgroups A (9 patients, mean age 49.6 years) with LAD stenosis > or = 90% and subgroups B with LAD stenosis between 70% and 90%. ST elevation occurs in 5 patients (55.5%) of subgroup A and in no patient of the subgroup B. Moreover, in the subgroup A ST elevation seems to be related to the anatomic localization of the stenosis: in fact it appears in 83.3% of patients with LAD stenosis located before the onset of the first diagonal branch. CONCLUSIONS: From these data it can be desumed that ST elevation in V1-V2 that occurs in patients with exertional angina and without myocardial infarction or variant angina is strongly predictive of a very important LAD stenosis.

Adult↗

PubMed1993

[Evolution of pacing modes in patients with implanted pacemakers. Personal considerations on a case load of 171 patients].

In this study retrospectively analyse pacemaker-implantation activity carried out during the last 5 years at the Laboratory of Electrophysiology, affiliated with the Cattedra di Cardiologia of the University of Naples--II Ateneo. Evolution in pacing modes is considered with regard to the patient age, the underlying pathologies and the technical progress in the field. The study has been performed in our laboratory, which is fit up for electrophysiologic studies and implantation of either temporary or permanent pacemakers. Patients included in this study have been implanted in our laboratory either for urgency or for election. They have been retrospectively divided into two groups (age < 65 yrs, 129 patients, and age < 65 yrs, 42 patients); in addition the patients have been classified according to the pathology leading to the implantation: atrio-ventricular block (second degree or third degree), low frequency fibrillation, sick sinus syndrome and carotid sinus syndrome. 171 patients have been examined, of whom 129 > 65 yrs. and 42 < 65 yrs. As for the pacing indication, 54 were atrio-ventricular block (56.1%), 50 were sick sinus syndrome (31.6%), 20 low frequency fibrillation (11.7%), and 1 was carotid sinus syndrome (0.6%). The ratio between single- and dual-chamber pacemakers has been progressively changing: in 1987 we implanted 33 single-chamber and no dual-chamber pacemaker, compared to 7 single- and 23 dual-chamber pacemaker implanted in the last year. This trend is in good agreement with literature data.

Aged↗

PubMed1992

Excimer laser ablation of a corneal protuberance.

The ablation of a post-traumatic superficial corneal nodule with an argon fluoride excimer laser is reported. Three months postoperatively the area had a smooth surface with no distortion of adjacent cornea.

Adult↗

PubMed1992

Bifocal versus monofocal intraocular lenses in bilateral pseudophakia.

After a mean follow up of 19 months, the visual characteristics of eyes with bifocal diffractive intraocular lenses (IOLs) ("bifocals") in one eye were compared with those of fellow eyes with monofocal IOLs ("monofocals") in 29 bilateral pseudophakic patients. All of the eyes had a distance-corrected acuity of 0.6 or more, but 24.1% of the bifocals and 48.3% of the monofocals had an acuity of 1.00. Near acuity with distance correction was J2 or more in 93.1% of the bifocals and in 17.4% of the monofocals (without correction: 79.3% and 41.4%, respectively). In 55.2% of the bifocals and 20.7% of the monofocals, the combined uncorrected acuity was 0.5 or more for distance and J2 or more for near. Fogging revealed a similar depth of focus in the monofocals and a similar distance focus in the bifocals. The bifocals had two peaks of acuity but no "plateau" between them. The eye with the monofocal IOL was preferred by 37.9% and the eye with the bifocal IOL by 10.3%. Vision in no eye was rated "poor." Visual disturbances were more frequent in the bifocals. No glasses were prescribed for 20.7% of all of these patients; 65.5% required bifocal glasses; 44.8% managed most of daytime without glasses.

Cataract Extraction↗

PubMed1991

Unilateral proliferative diabetic retinopathy and uveitis in the fellow eye: report of a case.

We report the case of a young man with a 20-year history of insulin-dependent diabetes mellitus, proliferative diabetic retinopathy OD, and uveitis OS. None of the common reported causes contributing to this difference between eyes was present. No features of diabetic retinopathy appeared OS after a follow-up of 36 months. This is the first case, to our knowledge, in which uveitis appeared to be associated with an asymmetric presentation in diabetes.

Adult↗

PubMed1991

[EGG and arrhythmia in subjects with implanted dual-chamber VDD and DDD pacemakers].

The ECGs of four patients with implanted dual chamber VDD and DDD PMKs are shown to demonstrate the difficulty of their interpretation and show some arrhythmias related to dual chamber pacing. In the first patient the DDD PMK caused a high ventricular frequency synchronizing on the atrial fibrillation "f" waves which occurred suddenly some time after PMK implantation; this problem was solved by programming the PMK in VVI. The second and third case, with implanted DDD and VDD PMK respectively, exemplify atrial sensing dysfunction due to atrial catheter displacement. In the fourth patient, with implanted VDD PMK, VDD stimulation periods and VVI ones alternated due to non-adjusted programming. Therefore, the paper re-emphasizes the need for accurate and periodic controls of patients with implanted PMK to correct dysfunction or undesirable patterns of stimulation.

Aged↗

PubMed1990

Argon versus krypton panretinal photocoagulation side effects on the anterior segment.

The modification of corneal sensitivity, accommodation, pupillary diameter and endothelial cell density after argon versus krypton panretinal photocoagulation were studied prospectively in 88 eyes of 64 diabetic patients with proliferative diabetic retinopathy, randomized for one of the two laser treatments. In both groups a marked internal ophthalmoplegia and reduction of corneal sensitivity occurred after laser photocoagulation. At no time, 2, 90 and 180 days after PRP, were these parameters significantly different. Endothelial cell loss was non significantly greater in the krypton group. The results indicated that the side effects commonly observed on the anterior segment after PRP are comparable using argon or krypton lasers.

Accommodation, Ocular↗

PubMed1990

[Iris vascular anomalies: angiographic aspects].

The authors report five cases of abnormal iris vessels observed in patients, without evident local or systemic pathology. These vessels, are dilated channels. On iris fluorescein angiography their filling appeared earlier than in normal stromal vasculature and was synchronous with that of conjunctival vessels. No dye leakage was present. Two functional angiographic pictures are observable: 1) vessels with abnormal diameter and path, approximately following normal iris vessel arrangement (case 1 and 2); 2) atypical vessels with wide communicating shunt between artery and vein without collaterals (cases 3, 4 and 5). These vessels are very tortuous and do not show any abnormality. The authors suggest to consider these anomalous vessels as anatomic abnormalities comparable with the arterio-venous communications of the retina.

Aged↗

PubMed1989

Prevalence of retinopathy in diabetic subjects from out-patient clinics in Lombardy (Italy), and associated risk factors. A multicentre epidemiologic study.

There is little information on the prevalence of diabetic complications in Italy. For this reason, a multicentre population-based study was carried out in 1983-1985 in 12 representative out-patient clinics for the treatment of diabetes in the Lombardy region. Out of a total population of 17,704 patients 1160 diabetic subjects were randomly selected within strata based on their duration of disease (less than or equal to 5; 6-10; 11-20; greater than 20 years). Eight hundred and thirty-eight responders were examined using standardised protocols. The estimated prevalences (adjusted for duration of disease) for the total population involved in the study were 29.7% and 7.6% for background and proliferative retinopathy respectively. The overall standardised rates were higher in insulin-dependent diabetes mellitus (IDDM) (53.6%) than in non-insulin-dependent diabetes mellitus (NIDDM) (34.7%) for both background (41.1%, 28.4% respectively) and proliferative (12.5%, 6.2% respectively) retinopathy, and increased with the duration of disease. The analysis of the relationship between diabetic retinopathy and the calculated risk factors did not show any association with hypertension or metabolic control, except for post-prandial blood glucose in subjects with durations 6-10 and greater than 20 years; an association with azotaemia was found in subjects with durations less than or equal to 5 and 11-20 years. Diabetic retinopathy appeared to be independently associated with the type of treatment and not with the type of diabetes, metabolic control, or hypertension.

Diabetic Retinopathy↗

PubMed1989

Clinical evaluation of the effect of acetylcholine on the corneal endothelium.

A transient corneal edema is often seen after the injection of acetylcholine solution in the anterior chamber during cataract surgery. Ninety eyes of 90 patients scheduled for extracapsular cataract extraction with posterior chamber intraocular lens implantation were randomly assigned to two groups: one which received acetylcholine solution in the anterior chamber and one, a control group, which received only external conjunctival pilocarpine drops as a miotic. At three days, endothelial folds (P = .04) and corneal edema (P = .01) were more pronounced in the acetylcholine group; at seven days, endothelial folds were more severe (P = .04) in the acetylcholine group. At 30 days, the acetylcholine group showed a 37.2% increase (P = .01) of the endothelial cell area, whereas the control group showed a 7.08% increase. The difference between the groups was statistically significant (P = .05). Anterior chamber fluorophotometry at 30 days showed an increase of the corneal transfer coefficient that was higher but not significant in the acetylcholine group. We suggest caution in the intraoperative use of acetylcholine solution, particularly in those eyes showing a preoperative compromise of the endothelium.

Acetylcholine↗

PubMed1989

[Clinical usefulness of the Doppler-echocardiographic method for evaluating intracardiac shunts. Combined Doppler and hemodynamic study].

The purpose of this study was to assess the accuracy of a quantitative two-dimensional Doppler echocardiographic method for estimating systemic and pulmonary blood flows in atrial and ventricular septal defects. Twenty-eight patients (mean age 22 +/- 14), with atrial septal defect (ADS) or ventricular septal defect (VSD) underwent Doppler-echocardiography and cardiac catheterization in order to assess pulmonary blood flow (QP), systemic blood flow (QS), the left to right shunt (SH) and the ratio of pulmonary to systemic flow (QP/QS ratio). Cardiac output was also determined by the oximetry method according to Fick principle. Pulmonary output assessed by Doppler was 7.9 +/- 0.61/min, by catheterization 9.0 +/- 3.9. Linear regression analysis showed a low correlation coefficient (r = 0.10; p = NS). Systemic output evaluated by Doppler resulted 4.6 +/- 1.4 l/m, while at catheterization 5.1 +/- 1.5 l/min (r = 0.25; p = NS). Doppler evaluation of left-to right shunt was 3.3 +/- 1.5 l/min, at catheterization 3.9 +/- 3.1 (r = 0.74; p less than 0.001). Doppler QP/QS ratio resulted 1.7 +/- 0.5, at catheterization 1.8 +/- 0.5 (r = 0.96; p less than 0.0010. The results showed that, in spite of the lack of correlation between the pulmonary and systemic outputs assessed by Doppler vs catheterization, QP/QS ratio, as well as SH, are useful noninvasive indexes in order to evaluate intracardiac shunts.

Adolescent↗

PubMed1988

Bullous retinal detachment in diffuse retinal pigment epitheliopathy.

Central serous choroidopathy can occur in an atypical, severe clinical expression also known as diffuse retinal pigment epitheliopathy. We report two cases in which this affection was complicated by a bullous retinal detachment of the lower quadrants. In one case the subretinal leaking point was photocoagulated. The evolution was favourable in both cases with resolution of the detachment and partial recovery of the visual acuity.

Adult↗