PubMed Health⌕ Search

Biomedical subjects

M Manfrin

Publications and source records attributed to M Manfrin.

At least 19 recordsLinked to original sources
PubMed2000

Periodic alternating nystagmus and vestibulo-spinal system facilitating activity.

OBJECTIVE: Periodic alternating nystagmus has been associated with the instability of the velocity storage mechanism, which is known to play an important role in both the vestibulo-oculomotor and the optokinetic systems. In the present study we looked for a possible spinal equivalent to PAN. METHODS AND RESULTS: In 3 PAN patients, the H-reflex amplitude proved to be slightly but significantly influenced by nystagmus direction, in that it was greater when the nystagmus was beating toward the stimulation side. CONCLUSIONS: This finding suggests that projections from velocity storage may play a role not only in the ocular motor but also in assisting postural stability through the vestibulo-spinal system.

Adolescent↗
PubMed1999

[Postoperative follow-up of type A aortic dissectionexperience with 67 patients].

BACKGROUND: The surgical treatment of type A aortic dissection is usually palliative and most surviving patients remain at considerable risk to develop late postoperative complications; consequently, there is the need for careful long-term follow-up. The present study reports on our experience in the postoperative follow-up of a consecutive series of patients with type A aortic dissection. METHODS: Between January 1986 and December 1996, 89 patients underwent emergency surgery for type A acute aortic dissection; the overall hospital mortality rate was 22% (20/89). This study includes the 69 hospital survivors (49 men and 20 women). Forty-six patients had ascending aortic graft replacement, 13 patients underwent replacement of aortic valve and ascending aorta by a composite graft. The surgical repair was extended to the aortic arch in 5 patients. All patients were serially evaluated by clinical examination and imaging techniques (transthoracic echocardiography in all patients, magnetic resonance imaging in 40, transesophageal echocardiography in 33 and computed tomography in 25). Follow-up was complete in 97% of patients (two patients were lost to follow-up and excluded from the study) and extended to a maximum of 152 months (mean 74 +/- 39 months). The postoperative quality of life was assessed by a questionnaire in 51 current survivors. Risk factors for cardiovascular death, reoperation and poor quality of life were investigated with univariate and multivariate analysis. RESULTS: During the follow-up period 15 patients (22%) died; in 13 cases death was due to cardiovascular causes and in 6 of them it was related to aortic disease. The Kaplan-Meier survival was 92 +/- 3%, 87 +/- 5%, 78 +/- 6% and 70 +/- 8% at 2, 4, 6 and 8 years, respectively. A persistent aortic dissection was demonstrated in 50 patients (75%) and 42 of them showed the presence of flow in the false lumen. A dilatation of one or more aortic segments was found in 59 patients (88%), with a diameter > or = 50 mm in 17 and > or = 60 mm in 8. In 30 patients who underwent transesophageal echocardiography the relation between aortic dimensions and flow pattern in the false lumen was examined; the presence of aneurysmal dilatation with a diameter > or = 50 mm was significantly correlated with a "high flow" pattern. Ten patients (15%) underwent reoperation from 13 to 83 months postoperatively. Reoperation was indicated for: sinus of Valsalva aneurysm and severe aortic regurgitation (2 patients), severe aortic regurgitation (2 patients), aneurysm of the arch (1 patient), thoracoabdominal aneurysm (1 patient), periprosthetic pseudoaneurysm (4 patients). The hospital mortality rate was 20% (2 patients). Sixty-two% of current survivors are asymptomatic; 30 patients returned to their predissection status. Quality of live is judged "good" by 23 patients, "fairly good" by 21 patients and "poor" by 7 patients. No significant independent risk factor for cardiovascular death, reoperation and poor quality of life was identified. CONCLUSIONS: The long-term prognosis after surgical treatment of type A aortic dissection is not satisfactory because of a significant risk of late complications. However, the results of our study can be judged fairly good, particularly if we consider the natural history of the disease.

Aged↗
PubMed1998

Evaluation of mean right atrial pressure by two-dimensional and Doppler echocardiography in patients with cardiac disease.

BACKGROUND: Several approaches have been used for noninvasive estimation of right atrial pressure (RAP), but, no currently available method has gained any definite validation. The purpose of this study was to evaluate the accuracy of two-dimensional and Doppler echocardiography in estimating mean RAP in patients with cardiac disease. METHODS: We examined the relation of mean RAP to right atrial size and function, size and respiratory changes of inferior vena cava and Doppler parameters of tricuspid and hepatic vein flow in 114 consecutive patients (77 men, 37 women; mean age 57 +/- 12 years) with various cardiac diseases undergoing cardiac catheterization. Echocardiographic studies were performed within 24 hours before catheterization (mean interval 6 +/- 3 hours). Patients were assigned to 3 groups according to the values of mean RAP (group 1, < or = 8 mmHg; group 2, between 9 and 12 mmHg; group 3, > 12 mmHg). RESULTS: Mean RAP ranged from 3 to 20 mmHg (mean 9.1 +/- 4.3 mmHg). It correlated most strongly with the collapsibility index of inferior vena cava (IVCCI) (r = -0.76), minimal inspiratory diameter of inferior vena cava (r = 0.72) and deceleration time of early tricuspid flow (DT) (r = -0.61). Discriminant analysis demonstrated that IVCCI and DT were major determinants of mean RAP with 81.6% of cases correctly assigned to study groups: 96% of patients of group 1 and 87% of patients of group 3 were identified, whereas the accuracy in identifying the patients of group 2 was lower (46%). An IVCCI > 45% was the best cutoff point in predicting a mean RAP < or = 8 mmHg; an IVCCI < 35% and a DT < 150 msec were the best cutoff points in predicting a mean RAP > or = 15 mmHg. The best multivariate equation predicting mean RAP was: mean RAP = 23.3 - 0.2 IVCCI -0.026 DT (r = 0.80, R2 = 0.64). This equation was 81% sensitive and 84% specific in detecting a mean RAP < or = 8 mmHg and 74% sensitive and 97% specific in detecting a mean RAP > 12 mmHg. CONCLUSIONS: Mean RAP can be estimated noninvasively by two-dimensional and Doppler echocardiography. The combined analysis of IVCCI and DT provides an accurate prediction on mean RAP < or = 8 mmHg and > 12 mmHg, whereas the prediction of intermediate values is less accurate.

Adult↗
PubMed1998

Constrictive pericarditis presenting as unexplained recurrent pleural effusion: a case report.

Constrictive pericarditis may exceptionally present as pleural effusion of unknown origin and this form of presentation may cause diagnostic problems. We report a case of subacute constrictive pericarditis in which there were recurrent pleural effusion with no other signs of the disease and the initial echocardiographic study was nondiagnostic. For this reason the patient was initially considered to have primary pulmonary or pleural disease. On the basis of the subsequent development of signs of systemic congestion and the results of computed tomography, Doppler echocardiography and cardiac catheterization, which were consistent with constriction, it was concluded that the patient had constrictive pericarditis. A complete resolution of pleural effusion and signs of systemic congestion was observed following pericardiectomy.

Acute Disease↗
PubMed1995

Osmolar changes and neural activity in frog vestibular organs.

The effects of hypotonic and hypertonic solutions (the normal value was 240 mOsm) on posterior canal resting and evoked discharge were studied in isolated labyrinth preparations. Hypotonic solutions (60-180 mOsm) were obtained by reducing the perilymphatic NaCl content. Hypertonic solutions (300-420 mOsm) were obtained by adding to normal perilymphatic solutions suitable amounts of NaCl, glucose, sucrose, glycerol, mannitol and urea. The results demonstrated that any kind of receptor activity was inhibited by hypotonic solutions. On the contrary, hypertonic solutions produced different effects on resting and evoked activity. The resting discharge was, with the exception of urea, constantly increased whereas the evoked responses were constantly decreased by all the hypertonic solutions tested. The possible effects of media with changed osmolarity in Meniere's patients is also discussed.

Animals↗
PubMed1994

Benign paroxysmal vertigo of childhood: a long-term follow-up.

We examined clinical aspects of Benign Paroxysmal Vertigo (BPV) in infancy and its most frequent differential diagnosis, in particular analogies and differences with forms of "migrainous vertigo" (MV) of later onset. During a long-term follow-up of 7 cases of BPV, diagnosed according to the Basser criteria, 5 of 7 BPV cases spontaneously resolved and 6 of 7 patients later developed migraine and other migraine-related symptoms. This course differs from that described for MV only in the age of onset of headache and in the chronological relationship with vertigo. The authors suggest that BPV can be interpreted as a migraine precursor and MV as a migraine equivalent.

Age of Onset↗
PubMed1994

[The false image of a left atrial mass due to a hiatal hernia: a case report].

We report the case of a 69-year-old woman with a history of hypertension and transient ischemic attack who was admitted because of a diagnosis of left atrial mass on transthoracic echocardiography. Monoplane transesophageal echocardiography showed an extracardiac mass compressing the left atrium posteriorly and an apparent intraatrial mass. As the procedure did not clarify the nature of the masses, a thoracic magnetic resonance imaging was performed. This technique revealed a large hiatal hernia impinging on the left atrium without evidence of an upper gastrointestinal tract. Our experience confirm that hiatal hernia may mimic an echocardiographic left atrial mass and should be considered in the differential diagnosis of this finding.

Aged↗
PubMed1991

Effects of hydrostatic pressure on sensory discharge in frog semicircular canals.

The effects of endolymphatic and perilymphatic pressure changes on resting and mechanically evoked responses were studied in isolated posterior semicircular canals of the frog. The results demonstrated that ampullar receptors are extremely sensitive to hydrostatic pressure changes (0.25 mm H2O were sufficient to produce distinct changes), being inhibited by endolymphatic pressure increases and facilitated by perilymphatic ones. Intracellular recordings from single afferent axons showed that the effects of hydrostatic pressure result from a modified transmitter release from the synaptic pole of the hair cells. Unlike resting activity, mechanically evoked activity was always depressed in the presence of a hydrostatic pressure. This indicates that the sensitivity of ampullar receptors to mechanical stimuli, i.e. the gain of the conversion process, is maximal when no pressure is present between the inner and the outer fluid. The possible action of hydrostatic pressure on vestibular receptors is discussed.

Afferent Pathways↗
PubMed1991

[Competitive sports activity in subjects undergoing the surgical correction of an ostium-secundum type of interatrial defect: the experience of 9 cases].

Patients who have undergone surgical repair of congenital heart diseases are usually not allowed to participate in competitive sports. In the present study we report our long-term experience with 9 male athletes aged 17 to 23 years who participate in competitive sports after undergoing surgical repair of ostium secundum atrial septal defect at a median age of 9 years; six of them play football and three of them volleyball. Competitive sport activities began 1 to 5 years after surgical repair. The mean duration of follow-up is 88 +/- 26 months. Sport fitness was granted on the basis of the following criteria: 1) a normal physical examination; 2) a normal working capacity on exercise test; 3) no arrhythmias on exercise test and Holter monitoring, recorded also during sport activities; 4) a normal M-mode and two-dimensional echocardiography, including the normalization of right ventricular size; the persistence of an abnormal ventricular septal motion did not exclude sport fitness. Recently we also performed Doppler and color Doppler echocardiography and gated equilibrium radionuclide angiography at rest and during exercise. We studied left ventricular diastolic filling through the pulsed wave Doppler evaluation of transmitral flow and measured cardiac output by continuous wave Doppler echocardiography during exercise test in the supine position. We also performed exercise test and M-mode, two-dimensional, Doppler and color Doppler echocardiography in a control group made up of 15 athletes (10 football players and 5 volleyball players). The exercise duration at graded treadmill exercise test (according to the Carù protocol), the maximal heart rate and the maximal systolic blood pressure were, respectively, 12.9 +/- 0.8 min, 192 +/- 10 beats/min and 198 +/- 12 mmHg. Left ventricular end-diastolic dimension, mass and ejection fraction (single-plane area-length method) were 50.3 +/- 2.8 mm, 210 +/- 38 g and 65 +/- 6%. M-mode right ventricular diastolic dimension was 23.4 +/- 1.6 mm; the right ventricular maximal diastolic diameter and area obtained on two-dimensional echocardiography from the apical four chamber view were 44.1 +/- 3.6 mm and 25 +/- 3.8 cm2 respectively. The evaluation of transmitral flow showed the following data: E velocity 77 +/- 12 cm/sec, A velocity 45 +/- 6 cm/sec, E/A ratio 1.7 +/- 0.3, the isovolumic-relaxation period 72 +/- 8 m/sec and the deceleration half-time of the early rapid filling 71 +/- 10 m/sec. A trivial tricuspid regurgitation was detected in 6 subjects; the peak velocity of the regurgitant jet was less than 2.1 m/sec.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1990

Expert systems as a diagnostic aid in otoneurology.

Expert systems (ES) are a new tool for information processing developed by the branch of computer science known as artificial intelligence. ES are capable of solving problems in a given domain by using the knowledge and emulating the behaviour of specialists in that field. ES can be used as powerful tools for education since they are able to justify their own conclusions and to make the underlying reasoning explicit. This paper presents 'Vertigo', an ES aimed at the classification and diagnosis of different forms of dizziness. It has been conceived mainly as a teaching tool in otoneurological departments. The rationale of this project, its development, the structure and the use of the system are described. So far, 'Vertigo' has been tested on more than 200 cases of dizziness and is presently being used by ENT residents during their otoneurology stage.

Diagnosis, Computer-Assisted↗
PubMed1983

[Multiple lentiginosis and hypertrophic obstructive cardiomyopathy].

Two patients with Multiple Lentiginosis (ML) had hypertrophic cardiomyopathy with severe obstruction of the right and left ventricular outflow tracts. ML is a rare syndrome in which there is a typical skin pigmentation disorder together with various other abnormalities like slight mental retardation, sensorineural deafness, genital and skeletal anomalies and sometimes a characteristic facies. Obstruction of the right ventricular outflow tract is frequent in such patients. The association of ML and obstructive hypertrophic cardiomyopathy has been recently reported. A critical examination of the literature in addition to our clinical observations suggests that the biventricular obstructive hypertrophic cardiomyopathy may play a major role in the clinical feature of ML syndrome.

Cardiomegaly↗