Our operative technique for inguinal hernia.

The most commonly used methods of hernia repair are either Bassini repair or modifications of Bassini repair in fact each sutures, with different methods, the three anatomical coats (transversalis fascia, transversus abdominis and internal oblique muscles, external oblique muscle aponeuroses). Here we propose a different operative technique that sutures only two aponeurotic coats (transversalis fascia and over external oblique muscle aponeuroses). The second sutured coat supports the posterior wall of the inguinal canal. Between 1984 and 1989 we operated about 1100 patients with this method and the recurrence rate is in accordance with the incidence of the other usual types of hernia repair.

["Incomplete closure" of the mitral valve: the relationships to valvular regurgitation and to the morphofunctional characteristics of the left ventricle]. / "Chiusura incompleta" della mitrale: rapporti con il rigurgito valvolare e con le caratteristiche morfofunzionali del ventricolo sinistro.

OBJECTIVES: The present study was designed in order to evaluate the prevalence of mitral regurgitation in patients with the "incomplete mitral leaflet closure" echocardiographic pattern, to verify whether the amount of "incomplete mitral leaflet closure" is related to the severity of mitral regurgitation and, last, to verify the relation between the "incomplete mitral leaflet closure" and left ventricular morphology and function. METHODS: We studied 80 patients (14 patients with dilatative cardiomyopathy, 26 patients with coronary artery disease, and 40 patients with hypertensive heart disease or aortic valve disease) showing the "incomplete mitral leaflet closure" pattern, retrospectively selected from a population composed of 1700 consecutive patients routinely examined in our echocardiographic laboratory. In all patients we evaluated the presence and the severity of mitral regurgitation, the morphological and functional parameters of the left ventricle, the systolic diameter of the mitral annulus, the distance between the point of mitral leaflet coaptation and the annular plane, and the incomplete mitral closure area, assuming the last two parameters as indexes of the severity of incomplete closure of the mitral valve. RESULTS: We observed the presence of mitral regurgitation in 51 out of 80 patients (64%). The valvular insufficiency was considered mild in 78% of the patients. We observed no significant difference between patients with mitral regurgitation and without, as regards the diameter of the mitral annulus, the distance between the point of mitral leaflet coaptation and the annular plane, and the incomplete mitral closure area in different types of heart diseases. The incomplete mitral closure area and the diameter of the mitral annulus showed a significant, although not elevated, correlation with the severity of the mitral regurgitation (r = 0.36 and r = 0.32, respectively). The severity of mitral regurgitation showed significant correlations with all of the left ventricular morphological and functional parameters evaluated. Finally, we observed significant correlations between the incomplete mitral closure area and all of the morphological and functional parameters of the left ventricle. CONCLUSIONS: On the basis of the results obtained we can conclude that: 1) the "incomplete mitral leaflet closure" pattern does not appear to be a highly specific marker of mitral regurgitation, 2) this pattern appears to be related to the morphology and function of the left ventricle, and 3) the severity of the incomplete mitral valve closure is more easily evaluated by a parameter that takes into account the numerous factors acting on the mitral apparatus, that is the incomplete mitral closure area.

[Myocardial response to ischemia produced by repeated coronary occlusions: an experimental study]. / Risposta miocardica all'ischemia prodotta da occlusioni coronariche ripetute: studio sperimentale.

BACKGROUND: The fact that brief repeated episodes of ischemia may induce prolonged functional depression of the left ventricle is still a matter of debate. During an angioplasty several brief (20-90 sec) coronary occlusions are performed, with the potential risk of inducing myocardial jeopardy. METHODS: We performed 4 repeated LAD occlusions in 7 open chest pigs under general anesthesia and controlled ventilation. The following parameters were evaluated: mean systemic arterial pressure (MAP), left ventricular peak systolic pressure (LVPSP), heart rate (HR), and peak negative and positive dP/dt (dP/dt- and +). Each parameter was measured in the basal state and every 4 sec, in the expiratory phase, during the coronary occlusion, the first min and after 10 min of reperfusion. The percent change from control values for each parameter was also calculated and, by means of the ANOVA test, the differences among the 4 consecutive occlusions for each parameter were tested. RESULTS: The results showed that: 1) coronary occlusions significantly depressed dP/dt + and -, MAP and LVPSP, while HR did not change; 2) each variable returned to control values within 1 min of reperfusion; 3) the response to ischemia (percent change) was the same in each of the 4 consecutive occlusions for all parameters at every recording time. CONCLUSIONS: We can conclude that: 1) each experimental coronary occlusion induces a depression of myocardial function that is reversible in 1 min of reperfusion; 2) four repeated 2 minutes coronary occlusions do not induce cumulative effects on myocardial response to ischemia.

Hemodynamic effects of nifedipine in patients with asymptomatic aortic regurgitation: evaluation by Doppler echocardiography.

Nineteen asymptomatic patients affected by isolated chronic aortic regurgitation received 20 mg of nifedipine sublingually: the acute hemodynamic effects of nifedipine were evaluated by combined cross-sectional and Doppler echocardiography. To assess variations in the regurgitant flow volume, the flow volume across the mitral and aortic valves was calculated as the product of velocity-time integral multiplied by the orifice valve area. Flow volume across these valves represented the total stroke volume, and forward stroke volume, respectively: the regurgitant volume was obtained by calculating the difference between total and forward stroke volume. Nifedipine induced a redistribution of the two components of the total left ventricular stroke volume: regurgitant stroke volume decreased from 57 +/- 22 ml/beat to 46 +/- 21 ml/beat (P < 0.002), while forward stroke volume increased from 83 +/- 12 to 93 +/- 15 ml/beat (P < 0.0005), as a consequence of the reduction in systemic vascular resistance from 1513 +/- 378 to 1092 +/- 307 dynes.sec.cm-5 (P < 0.0001). The reduction of regurgitant volume was due to either a 24.8% decrease of the aortic-left ventricular mean pressure gradient during diastole (P < 0.008) or a 6% decrease of the diastolic time interval (P < 0.04). The effect of these acute changes on left ventricular loading was to induce a reduction in oxygen consumption which was expressed by a decrease in the double product (from 10176 +/- 1767 to 9444 +/- 1559 mmHg.beats/min; P < 0.002), in spite of a significant increase in heart rate. This study, therefore, shows the beneficial acute hemodynamic effect induced by nifedipine in asymptomatic patients affected by chronic aortic regurgitation and shows that Doppler-echocardiography is a useful instrument for the evaluation of hemodynamic changes immediately after the administration of drugs.

Effects of venous return reduction in hypertensive patients: is there a Doppler diastolic dysfunction index independent of preload reduction?

The aim of this study was to evaluate the effects of preload reduction on the Doppler transmitral flow pattern in the presence of diastolic dysfunction (hypertensive patients) and normal diastolic function (normal subjects) to identify, if present, one or more indexes of abnormal diastolic ventricular filling independent of variations in preload. For this purpose Doppler echocardiography was performed in 17 patients with hypertension and in 18 normal subjects under basal conditions and after 5 minutes of blood pressure cuff inflation at the root of the four limbs. The two groups showed a similar response to preload reduction: a significant reduction in peak velocity and the time-velocity integral of the E wave and in the ratio of peak velocities of E and A waves. Therefore the differences in left ventricular filling patterns between hypertensive and normal subjects observed under basal conditions were still present after preload reduction. The comparison between normal subjects after preload reduction and hypertensive patients in the basal state showed a higher peak velocity and time-velocity integral of the A wave in the latter (61.2 +/- 16.2 vs 46.2 +/- 9 cm/sec [p less than 0.002] and 5.4 +/- 1.8 vs 3.7 +/- 1 cm [p less than 0.002], respectively) with no differences in the ratios of peak velocities and time-velocity integrals of the E and A waves.(ABSTRACT TRUNCATED AT 250 WORDS)

New perspectives in the assessment of cardiac chamber dimensions during development and adulthood.

The use of body surface area to assess the normalcy of cardiac dimensions has several limitations. To determine whether cardiac dimensions can be assessed by other indexes of body size and growth, this study evaluated the relations between cardiac dimensions assessed by two-dimensional echocardiography and age, height, weight and body surface area. The study group included 268 normal persons aged 6 days to 76 years of age. The dimensions examined included the aortic anulus, left atrium and left ventricular end-diastolic diameter, each measured in the parasternal long-axis plane, and left ventricular length measured from the apical two-chamber view. The analysis confirmed that the heart and great vessels grow in unison and at a predictable rate after birth, reaching 50% of their adult dimensions at birth, 75% by 5 years and 90% by 12 years. Although each cardiac dimension related linearly with height (aortic anulus, r = 0.96; left atrium, r = 0.91; left ventricular diameter, r = 0.94; left ventricular length, r = 0.93), the relations among age, weight and body surface area were best expressed by quadratic equations. Multiple regression confirmed that after adjustment for height, other indexes including age, gender, weight and body surface area had no independent effect on the prediction of each dimension. Therefore, because height is a nonderived variable that relates linearly with cardiac dimensions independent of age, it offers a simple yet accurate means of assessing the normalcy of cardiac dimensions in children and adults.

[Effects of low-dose diltiazem on isovolumetric relaxation and contraction]. / Effetti del diltiazem, a basse dosi, su rilasciamento e contrazione isovolumetrica.

Calcium entry blockers are commonly believed to have a direct negative inotropic effect, but systolic function of the left ventricle (LV) can be improved when the peripheral vasodilator activity of the drug is present. The aim of our study was to evaluate the effect of diltiazem (D) on isovolumic contraction (IC) and relaxation (IR) at a dosage which is not effective on the peripheral vascular bed. We infused 10 micrograms/Kg/min i.v. of D for a 30 min period in to 12 pigs, anesthetized with ethyl urethane (1250 mg/Kg) and under artificial ventilation. The following variables were evaluated: left ventricular systolic (LVSP) and end-diastolic (LVEDP) pressure, peak - and + dP/dt, mean arterial pressure (MAP), heart rate (HR) and double product. The recordings were obtained in the control condition and 5, 10, 15, 20, 25 and 30 minutes after beginning the infusion. The statistical analysis was performed using the one-way ANOVA test. Our results show: 1) a maximal increase in the peak + dP/dt from 2228 +/- 501 to 2448 +/- 576 mmHg/sec (p less than or equal to 0.01) and of the peak . dP/dt from 1262 +/- 260 to 1348 +/- 272 mmHg/sec (p less than or equal to 0.05); 2) and increase in LVSP from 86 +/- 13 to 90 +/- 10 mmHg (p less than or equal to 0.01) and 3) no changes in HR, PAM, LVEDP and double product. As the indices representing afterload and preload (PAM and LVEDP) remained unchanged during the infusion, we suggest that the increase in dP/dt + and - are due to a direct effect of diltiazem on myocardial function.(ABSTRACT TRUNCATED AT 250 WORDS)

Left atrial dimensions in growth and development: normal limits for two-dimensional echocardiography.

Reference values for normal left atrial dimensions have been based primarily on blind M-mode measurements, with no reports based on two-dimensional echocardiography to provide a comprehensive analysis of the two-dimensional measurements from infancy to old age. This report analyzes the left atrial dimensions from two-dimensional echocardiographic studies in 268 normal healthy subjects to determine normal limits and relations among linear, area and volume measurements of the left atrium. The group mean values change with body size, fitting well to the exponential growth model (r = 0.78 to 0.92). The variance about the mean (which determines normal limits) is represented effectively by a quadratic function of body surface area (r = 0.84 to 0.99). The variables determined by this modeling simplify evaluation of normal limits for any body size at any desired level of confidence, and the data are useful reference standards for interpretation of two-dimensional echocardiograms.

Effects of preload reduction on mitral flow velocity pattern in normal subjects.

In the last few years, alterations in transmitral diastolic flow pattern have been used to assess changes in left ventricular diastolic properties. However, since diastolic flow primarily reflects the atrioventricular pressure gradient, loading conditions, as well as intrinsic left ventricular properties, should be able to affect this pattern. This study was selectively designed to decrease preload (a major determinant of the atrioventricular pressure gradient) in normal subjects to observe the effects on the Doppler transmitral flow pattern without pharmacologic interventions that may also affect left ventricular diastolic properties. In 12 normal subjects, preload was reduced by inflation of blood pressure cuffs placed at the level of the root of the 4 limbs. The peak velocity of early mitral flow (E wave) decreased from 62 +/- 8 to 51 +/- 7 cm/s (p less than 0.001), while no changes were found in the maximal velocity after atrial contraction; this caused a significant decrease in the ratio of these 2 velocities (the E to A ratio) from 1.5 +/- 0.3 to 1.1 +/- 0.1 (p less than 0.001). The time-velocity integral of early diastolic inflow decreased from 7.8 +/- 1.3 to 6.1 +/- 1.3 cm (p less than 0.001) with no significant changes of the time-velocity integral of inflow after atrial contraction. Therefore, preload reduction in normal subjects significantly reduces transmitral flow in early diastole with preserved late ventricular filling, producing a pattern that can mimic the changes previously described in left ventricular diastolic dysfunction.

[A comparison between mitral and aortic outputs evaluated by Doppler echocardiography in a group of healthy subjects: false regurgitation]. / Confronto tra portata mitralica ed aortica valutate con eco-Doppler in un gruppo di soggetti sani: il falso rigurgito.

Doppler echocardiography is a potentially useful tool for the non invasive evaluation of cardiac output and, therefore, for the quantitative assessment of valvular regurgitation. The aim of our study was to establish the presence of possible pitfalls in the evaluation of mitral and aortic regurgitant fraction obtained by Doppler echocardiography comparing the cardiac output measured at the level of the mitral and aortic valve. For this purpose 19 healthy volunteers, aged between 14-68 years, were studied. Stroke volume and cardiac output were calculated at the level of the mitral and aortic valve. The methods we used for the measurement of both the mitral and aortic cardiac output had already been validated and presumes that the shape of the valve annulus, is circular. No statistically significant differences were found between the parameters obtained at the two different valvular levels. Furthermore, cardiac output values correlated fairly well (r = 0.83, ESS = 0.78 l/min). In 9 subjects the aortic cardiac output was greater than the mitral one, while in the others mitral cardiac output was greater. The average of the differences between the two cardiac outputs was 0.58 +/- 0.48 l/min with a regurgitation fraction of 9.5 +/- 7.9%. Our results show that the mitral and aortic stroke volume and cardiac output, as measured by Doppler echocardiography (considering a circular shaped valve annulus, are not statistically different and correlate fairly well in our normal subjects. Nevertheless, we observed a certain degree of variability between the mitral and the aortic cardiac output.(ABSTRACT TRUNCATED AT 250 WORDS)

[Model for an epidemiological study of the health status of a population of health workers]. / Contributo per un modello d'indagine epidemiologica sullo stato di salute di una popolazione di operatori sanitari.

The authors describe a model of retrospective research on the state of health in a sample of the staff in a big hospital. The sample was composed of selected sub-groups taken from professional categories notoriously exposed to risk at work. The aim was to help define a model in simple ad versatile epidemiologic research and by applying it to a sample population of health operators, to verify the extent, the prevalence and incidence, the evolution in pathologies in order to make comparisons with the normal population, thus making it easier, for future research, to study casual phenomena and correlate between them. General criteria of retrospective "control case" have been adopted and the anamnestic data gather in has been done by filling in the "health book of individual risk", together with special questionnaires for this investigation. The originality of this work consists in its having abandoned the concept of pre-determine the nature and size of the test sample. In fact, considering the large number of variables, they should have made use of much bigger dimensions than the ones of the population examined with the elaborated original model. Which mean it is possible to obtain significant and reliable results by operating on a reduced but statistically valid sample, chosen with random method and whose entity has been determined with support from others experience in different sector. Therefore it is reasonable to consider the described model as a simple, agile and economic instrument adaptable to other cases, although still to be perfected. In particular it underlines the possibility of testing the state of health of categories at risk before stating complicated analysis (and organi) or big populations, thus improving instruments ad organization. To accomplish a continuous system of data in a short time thus verifying the stages of development and application of more complex projects of epidemiologic research aimed at entire populations. To obtain useful information wherever it's not possible to conduct complete and rapid research on workers' health in an on going way.

Calculation of transmitral flow by Doppler echocardiography: a comparison of methods in a canine model.

Although several Doppler echocardiographic methods for measuring transmitral flow have been described, the optimal method for calculation of flow remains unclear. Seven time/shape combinations were tested in an experimental preparation in which mitral flow could be precisely controlled and measured. Annular shape was considered to be either circular or elliptical, and the mitral orifice area was calculated from the anteroposterior and/or the mediolateral dimension(s) recorded at early and middiastole. In addition the orifice area was calculated from the maximal mitral leaflet area corrected for diastolic variation. Transmitral flow ranged between 0.4 and 4.6 L/min. Good correlations with measured transmitral flow (r = 0.83 to 0.92) were observed for all methods of calculating the mitral orifice area. Methods that assumed a circular geometry and used the mediolateral annular diameter overestimated flow. Conversely, flows calculated by means of the anteroposterior diameter with the assumption of a circular anulus underestimated flow. The best approximations of transmitral flow were obtained with the assumption of an elliptical configuration that used measurements made in early diastole (Y = 1.04x + 0.2) and with the Fisher method (y = 0.94x + 0.08). Thus in the canine model approximation of the mitral orifice as an ellipse provides the most accurate measurement of transmitral flow.

[The "diagnostic day hospital." A proposal for functional support by hospital services and primary care]. / Il day hospital diagnostico. Una proposta di supporto funzionale dei servizi ospedalieri e di assistenza di base.

The general lack of nurses and the attention due to the purposes of efficiency, effectiveness and economy of hospital services oblige to better the cooperation between attending and family physicians, to improve the resources, the productiveness of clinicopathology, the use of daily hospital services (such as ambulatories, daily hospitalization and treatments) and emergencies. For this end the authors propose the realization of a day hospital which mainly aim is the diagnostic (D.H.D.) of internal medicine. The admission will be acted by a doctor of the emergency department and of the reception. The day hospital will be functionally linked up with the services of emergency dpt. and reception and with the outpatients' department. Therefore useful both for the attending and family physicians. This kind of day hospital shouldn't substitute the specialities (such as hematology, oncology, psychiatry, dialysis, rehabilitation, etc.) which finalities are principally the therapy and check-up of known patients who follow a treatment by a specialistic department. The D.H.D. should grant the following functions: --Diagnosis or provable orientation in case the doctor of the emergency dpt. or the specialist in ambulatory shouldn't be able to perform them immediately; --Clinical control of cases coming from the emergency dpt.; --Planning of therapeutic program and carrying out of ambulatory therapies that cannot be deferred, of cases coming from the emergency dpt. or reception. Then, is attributable to the D.H.D. the hospital statistics that: --requires clinical observation that cannot be deferred; --requires unerring, prompt and complex diagnostic orientation in order to decide the kind of ward where the hospitalization should be done; --if needed, hospital therapeutic intervention that cannot be deferred, incompatible with the operative possibilities of the D.H.D. The authors also deal with operative relations between D.H.D. and other hospital services, the staff organization, the location, dimension and functional attribution of the head office, the purchases and availability of sanitary fittings and furnishings. Finally, the authors estimate the effectiveness of D.H.D. as far as the reduction of continuative hospitalization is concerned.

Limits of normal left ventricular dimensions in growth and development: analysis of dimensions and variance in the two-dimensional echocardiograms of 268 normal healthy subjects.

The majority of studies generating normal echocardiographic reference values for left ventricular dimensions have been based on blindly performed M-mode measurements, and there are no previous reports based on two-dimensional echocardiography that provide a comprehensive analysis of the two-dimensional measurements from infancy to old age. This report presents the results of analyzing the left ventricular internal dimensions from cross-sectional echocardiographic studies on 268 normal healthy subjects (none were hospitalized for any reason) whose ages ranged from 6 days to 76 years. The mean data are reported as functions of body surface area and, in addition, the variance is modeled as a function of body surface area to provide an accurate and clinically useful determination of normal limits and to model changes in the cardiac dimensions and in their variance representing normal growth and development. The data fit well to the exponential growth model (r values 0.85 to 0.95). Variance about the central values also depended significantly on body size; that relation is represented effectively by a quadratic function of body surface area (r values 0.82 to 0.98). The model parameters allow calculation of normal limits at any desired level of confidence. Areas determined by hand planimetry have significantly greater variance compared with variance of linear dimensions, and also compared with variance of cross-sectional area using ellipses generated from the anteroposterior and mediolateral dimensions. This implies that either biologic variations in the amount of infolding or errors in freehand planimetry constitute a significant source of variance; this may be remedied by filtering out high frequency oscillations of contour. There is no significant difference in midnormal values and confidence limits for corresponding dimensions measured from orthogonal views. Furthermore, the anteroposterior and mediolateral dimensions of the left ventricle superimpose at each body size, consistent with circular cross section for normal subjects throughout growth and development. The data presented should comprise a useful set of reference standards for interpretation of cross-sectional echocardiograms.

[First seconds after acute experimental ischemic: changes in isovolumic contraction and relaxation]. / Primi secondi dopo ischemia acuta sperimentale: modificazioni della contrazione e rilasciamento isovolumetrici.

The purpose of this study was to answer the following questions: 1) are isovolumic contraction and relaxation affected in a different way by LAD occlusion? 2) Does proximal and distal LAD coronary occlusion induce different changes in isovolumic contraction and relaxation? In 22 pigs, LAD coronary artery was dissected free right after the first or third diagonal branch and occluded by ligation. The following variables were evaluated: left ventricular systolic and end-diastolic pressure; peak - and + dP/dt, mean arterial and pulmonary pressure. All our data were obtained in the first minute following the occlusion.(ABSTRACT TRUNCATED AT 250 WORDS)

The relationship of mitral annular shape to the diagnosis of mitral valve prolapse.

The geometric or anatomic diagnosis of mitral valve prolapse, as opposed to the pathologic diagnosis of myxomatous valve disease, is based on the relationship of the mitral leaflets to the surrounding anulus. Current echocardiographic criteria for this diagnosis include leaflet displacement above the annular hinge points in any two-dimensional view; implicit in this equivalent use of intersecting views is the assumption that the mitral anulus is a euclidean plane. Prolapse by these criteria is found in a surprisingly large proportion of the general population. In most of these individuals, however, prolapse is present in the apical four-chamber view and absent in roughly orthogonal long-axis views of the left ventricle. This frequently observed discrepancy between leaflet-annular relationships in intersecting views suggests an underlying geometric property of the mitral apparatus that would produce the appearance of prolapse in one view without actual leaflet distortion. To address this possibility, a model of the mitral valve and anulus was constructed. When the model anulus was given a nonplanar, saddle-shaped configuration, the clinical observations were reproduced: the leaflets appeared to lie above the low points of the anulus in one plane, and below its high points in a perpendicular plane. Therefore, the appearance of mitral valve prolapse can occur without actual leaflet displacement above the most superior points of the mitral anulus if the anulus is nonplanar. To determine whether this pattern is reflected in the human mitral anulus, two-dimensional echocardiographic views of the mitral apparatus were obtained by rotation about the cardiac apex in 20 patients without evident annular or rheumatic valvular disease. In all cases the mitral anulus, as reconstructed from these views, had a nonplanar systolic configuration, with high points located anteriorly and posteriorly. This is consistent with the findings of other groups in animals, and would favor the appearance of prolapse in the four-chamber view and its absence in long-axis views that are oriented anteroposteriorly. This model can therefore explain the frequently observed discrepancy between leaflet-annular relationships in roughly orthogonal views. It challenges the assumption that the mitral anulus is planar as well as the diagnosis of prolapse in many otherwise normal individuals based on that assumption.

[Anti-hepatitis B vaccination in health personnel at the Ospedale Maggiore of Milan]. / Vaccinazione anti-epatite B nel personale sanitario dell'Ospedale Maggiore di Milano.

The paper deals with the screening of the staff at the Ospedale Magiore of Milan within the Region-wide program of recommended B Hepatitis vaccination. The HBsAg positive subjects are 3.1% and antiHBs are 32.7%; the susceptibility of the infection decreases with age and working seniority; infection markers are found most frequently in subjects working in the Dialysis Ward. The health staff informed about the professional risk of infection is still reluctant for this immunization; in fact only 62.5% of susceptible accepted the vaccine. Seroconversion was observed in 89.8%; collateral reactions to vaccine were of minor importance and short duration.

[Functional evaluation of the autonomic regulation in mitral valve prolapse]. / Valutazione funzionale della regolazione neurovegetativa nel prolasso valvolare mitralico.

We examined fifty patients aged from 15 to 35 years, mean 23 +/- 5, with mitral valve prolapse (MVP) documented by two-dimensional echocardiography in the apical 4-chamber view as well as in the parasternal-long axis. The patients have been submitted to 4 tests: Valsalva maneuver, standing and exercise test and 24 hours ambulatory ECG monitoring. Fourty-five healthy subjects of similar age and sex served as controls. During the standing test the patients with MVP showed a significantly faster heart rate than the control subjects both in resting and in the standing position; during the exercise test they exhibited higher prevalence of ST segment and T wave abnormalities disappearing at the peak of the exercise. These observations support the hypothesis of a hyperadrenergic state. The greater bradycardia showed during the Valsalva maneuver, the lower heart rate and the higher incidence of bradyarrhythmias and A-V blocks during the sleeping period suggest an increased vagal tone. Our results suggest therefore that in subjects with MVP a dysfunction of both, sympathetic and parasympathetic nervous system is present.