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M Morpurgo

Publications and source records attributed to M Morpurgo.

At least 37 records · Page 2Linked to original sources
PubMed1997

[Electromechanical dissociation in myocardial infarction. Anatomical-clincal study of 82 cases].

UNLABELLED: In our experience electromechanical dissociation (EMD) is the most common mechanism of fatal cardiac arrest in patients with acute myocardial infarction (AMI). METHODS: We reviewed retrospectively 82 autopsy cases of AMI in whom the medical record documented EMD as terminal cardiac arrest in order to outline the clinical and pathologic features of different subgroups: 26 cases with external cardiac rupture (CR) were compared with 56 cases without CR. In turn, inside the latter series, 16 cases of sudden EMD were compared with 40 cases of EMD occurring in the terminal phase of cardiac shock. RESULTS: In comparison with those without CR, patients with CR showed at multiple regression analysis less evidence of left ventricular failure (p < 0.05); less extended infarct areas (p < 0.01); more frequent sudden EMD (p < 0.05). Most patients with CR had massive pericardial effusion; cardiac rhythm at the onset of EMD was seldom slow in those cases. In the group without CR no discriminant characteristics were found in cases of sudden EMD vs cases preceded by cardiac shock. CONCLUSIONS: In case of CR EMD occurs in less extensively damaged hearts and is generally sudden; in AMI without CR EMD may affect patients with severe depression of pump performance, but not necessarily in shock. EMD after an AMI may result from several factors: cardiac tamponade is prevalent in the presence of CR; in cases without CR our data don't permit to conjecture a distinct pathogenesis for sudden EMD in comparison with cases preceded by shock.

Aged↗
PubMed1996

Protective effect of superoxide dismutase and polyethylene glycol-linked superoxide dismutase against renal warm ischemia/reperfusion injury.

The protective effect of oxygen free radical scavenger superoxide dismutase (SOD) against the warm ischemic damage that occurs in kidneys harvested from non-heart-beating donors is controversial because of its short half-life. In this model, we compared the protective effect of SOD and two longer lasting polyethylene glycol (PEG)-linked forms of SOD in a model of renal ischemia induced by 60 min of arterial clamping in rats. Rats treated with PEG1-SOD and PEG2-SOD had a better renal function than controls, with significantly lower serum creatinine levels throughout the follow-up period and a significantly higher creatinine clearance on postoperative days 1, 2, and 4. In native SOD treated-rats, serum creatinine was lower than in controls, though not significantly so, and creatinine clearance was significantly higher on postoperative day 4. Our results indicate that the protective effect of SOD against renal warm ischemia can be enhanced by prolonging its half-life by binding the enzyme to PEG.

Animals↗
PubMed1996

The varying evolution of Friedreich's ataxia cardiomyopathy.

During a mean follow-up period of 8 years, 17% of 66 patients with Friedreich's ataxia developed hypokinetic-dilated cardiomyopathy; most patients originally had a hypertrophic left ventricle. The presence of pathologic Q waves identifies a subgroup of patients with wall motion abnormalities; these patients are more likely to develop a hypokinetic left ventricle, and the prognosis is ostensibly poorer.

Adolescent↗
PubMed1996

Covalent modification of mushroom tyrosinase with different amphiphic polymers for pharmaceutical and biocatalysis applications.

Two different poly(ethylene glycol) derivatives (linear, mol wt 5000 and a branched form, mol wt 10000) and a new polymer (poly-[acryloylmorfoline], mol wt 5500) were covalently bound to the enzyme tyrosinase. The polymer-protein conjugates were studied with a view to their potential pharmaceutical application and to their use for the bioconversion of phenolic substrates in organic solvents. Vmax and Km for the dopa-dopaquinone conversion, thermostability, stability toward inactivation by dopa oxidation products, half-life in blood circulation, and behavior in organic solvents for the different adducts were investigated. Arrhenius plots for the dopa-dopaquinone conversion were also obtained in order to study the effects of temperature on the different enzyme forms. Covalent attachment of the polymers increased enzyme stability in aqueous solution and the solubility in organic solvents. However, organic solvent solubilization brought about loss of enzyme conformation as assessed by CD measurements, which is accompanied by a nonreversible loss of catalytic activity.

Animals↗
PubMed1996

Does spontaneous respiration alter pulmonary artery input impedance?

The aim of this study was to determine whether spontaneous respiration influences pulmonary artery input impedance, a question that has received little attention in the literature. Impedance values were assessed during three different phases of the respiratory cycle, namely inspiration, expiration and postexpiration (i.e. the null respiratory flow period between expiration and the next inspiration) in five anaesthetized spontaneously breathing dogs. Firstly, impedance values during postexpiration were taken as the reference baseline, and compared with values obtained during inspiration and expiration. Then, differences between values in inspiration and in expiration were tested, taking impedance during inspiration as the baseline. Differences with respect to postexpiration were found for three parameters of input impedance: input resistance, characteristic impedance, and the frequency at the first zero-crossing of the impedance phase from negative to positive values (f(cross)). Input resistance was significantly lower in inspiration (85% of the baseline), characteristic impedance was significantly greater in inspiration and in expiration (112 and 119% respectively), and f(cross) was significantly lower in expiration (89%). By contrast, only input resistance differed significantly when inspiration was compared to expiration. Therefore, spontaneous respiration was shown to influence input impedance significantly. The observed changes in characteristic impedance and f(cross) might be explained by a stiffening of the pulmonary artery wall, due to neural and/or mechanical factors, during inspiration and expiration.

Animals↗
PubMed1995

The spectrum of pulmonary embolism. Clinicopathologic correlations.

Pulmonary embolism (PE) is still underdiagnosed even in hospitalized patients. In our recent experience, out of 92 postmortem cases of massive or submassive PE, only 28% were diagnosed before death, whereas the false-positives accounted only for 3% of cases. Similar conclusions have been drawn from large-scale autopsy studies performed in Norway and in the United States. The most important causes of an incorrect diagnosis are failure to suspect PE, and the protean nature of the disease. Remarkable differences actually exist concerning the point of origin and the final localization, as well as the size and age of thromboemboli, the presence or absence of pulmonary infarction, and the underlying pathology. Often a fatal embolus is relatively small but hardly tolerated because of the underlying cardiopulmonary situation. Attention should be called to the frequent autopsy finding of multiple PEs and pulmonary infarctions of apparently different age. This finding is important since it indicates that these patients suffered successive embolizations and the eventual death might have been prevented if an early diagnosis had been made.

Humans↗
PubMed1995

Pulmonary input impedance or pulmonary vascular resistance?

Pulmonary artery input impedance (PAII) expresses the opposition of pulmonary vessels to pulsatile blood flow, in the same way that vascular resistance expresses opposition to steady flow. PAII spectrum includes information concerning not only the mean blood flow, pressure and resistance, but also proximal vessels stiffness, pulse wave velocity and arterial wave reflection. It is an adequate expression of the right ventricular afterload, and it is quite suitable for the description of the right-ventricular-pulmonary arterial interaction. Pulsatile properties must be taken into account, for instance, to understand the effects of pulmonary vasodilation on cardiac output. Characteristic PAII is increased in pulmonary hypertension due to stenosis, pulmonary thromboembolic disease, and in unexplained pulmonary hypertension.

Blood Pressure↗
PubMed1994

[The early echocardiographic diagnosis of a massive pulmonary embolism].

BACKGROUND: In several cases of clinically suspected massive pulmonary embolism (MPE), a lung perfusion scanning and/or a pulmonary angiography are not quickly available or feasible. METHODS: Fifty patients admitted to our ICU with a clinically suspected MPE underwent an echocardiographic (Echo) investigation very shortly after onset (within 2 hours in 38 cases, and within 6 hours in 12). An Echo-Doppler study was also performed in 18 patients. RESULTS: Highly significant differences (p < 0.001) emerged between patients with PE and healthy age-mates for each type of Echo measurement and in all views. The RVDD/LVDD ratio turned out to be the most frequently affected parameter, being altered in 96% of cases. An abnormal diastolic leftward shift of the interventricular septum was detected in 81% of cases. Only one of our 50 patients failed to show any evidence of RV pressure overload; however, this was a patient with a severe dilated cardiomyopathy. In 22 cases in whom hemodynamic monitoring was performed, no significant correlation emerged between RVDD and LVDD, on one hand, mean PAP and cardiac index on the other. All 18 patients examined by Echo-Doppler had mild to moderate tricuspid regurgitation with a peak RV-RA gradient of 38 +/- 7 mm Hg (range 31-53 mm Hg). Seven patients (14%) were found to harbor right heart thrombi when first examined. Overall mortality in this uncommonly high risk population was as high as 28%. CONCLUSIONS: In a clinical setting suggesting a MPE, an Echo study conducted very shortly after onset may corroborate a tentative diagnosis of PE, thereby permitting timely fibrinolytic therapy pending a lung scan and/or angiography, or in situations where such imaging facilities are not available or readily usable.

Acute Disease↗
PubMed1994

[Heart arrest in acute pulmonary embolism. An anatomo-clinical study].

The Authors describe the modalities and mechanisms of cardiac arrest (CA) in the course of acute pulmonary embolism (PE). Clinical data refer to 39 CA episodes occurred in 28 patients with massive or submassive PE; autopsy data are from 26 of 28 patients of the same series. One-third of 39 CAs proved at least momentarily reversible; two-thirds were irreversible. Data analysis showed that most CA episodes, reversible or otherwise, seen in the course of PE were due to electromechanical dissociation (EMD). In fact, EMD was responsible for 12 of 13 reversible CAs and 22 of 26 irreversible arrests. EMD usually follows shock, but may occur unheralded. When EMD-induced CA is at least temporarily reversible, the heart rate is often normal or high and QRS complexes are narrow. In most cases the sudden rise of right ventricular afterload came on top of a pre-existing myocardial damage, for the most part of ischemic, sometimes necrotic, origin. In this series, therefore, it seems quite difficult to tell "primary" from "secondary" forms of EMD. External cardiac massage continued for as long as 40 minutes was associated in some cases with a bolus fibrinolytic infusion within minutes from occurrence of CA. Five of 7 patients so treated made a temporary recovery and two survived; at autopsy, none of the 5 patients who died showed any evidence of bleeding attributable to local injury.

Acute Disease↗
PubMed1992

Diagnosis, treatment, and prevention of pulmonary embolism. Report of the WHO/International Society and Federation of Cardiology Task Force.

To assess the state of the art of venous thrombosis and pulmonary embolism for the medical and other health-related professions, the World Health Organization (WHO) and the International Society and Federation of Cardiology (ISFC) convened a task force in Geneva, Switzerland. Members of the task force prepared position papers and presented brief oral presentations. A report was subsequently prepared by the task force members, who contributed sections in their areas of expertise. Revisions of the report occurred both during the task force meeting itself in Geneva and during the ensuing months. The final report was approved by the WHO-ISFC Task Force on Pulmonary Embolism Steering Committee. More quantitative information is needed on the frequency of venous thrombosis and pulmonary embolism in hospitalized medical patients as well as in outpatients at high risk. Population studies should focus on incidence, survival, and long-term complications in different parts of the world with respect to gender and race. Further educational efforts are needed to increase awareness about venous thrombosis and pulmonary embolism prophylaxis. Finally, research into effective techniques for changing physician practice would be useful.

Aged↗
PubMed1992

Role of echo/Doppler in the diagnosis of pulmonary embolism.

Echocardiography supplemented with pulsed and continuous wave Doppler facilities is a potent diagnostic tool in many cardiovascular disorders. Its potential role in the management of patients with suspected pulmonary embolism, though less extensively studied, deserves attention. Benefits of echo/Doppler in these patients are as follows: (1) Echo/Doppler is a noninvasive, relatively inexpensive technique, readily available and repeatable in critically ill patients at the bedside. (2) Echo/Doppler provides a number of independent parameters related to the pulmonary hemodynamics. These parameters include: (a) characteristics of blood flow velocity curves across the right heart valves as well as systolic and diastolic time intervals of the right ventricle (b) motion pattern of the interventricular septum (c) dimensions of the heart chambers and inferior vena cava (d) thickness of the right ventricular free wall (3) Echocardiography allows detection of thrombi within right heart chambers or in major branches of the pulmonary artery in some patients. (4) Echo/Doppler may disclose alternative abnormalities explaining symptoms found in a patient with suspected pulmonary embolism such as pericardial disease, myocardial infarction, aortic dissection, hypovolemic shock, etc.

Acute Disease↗
PubMed1992

Opposite hemispheric activations as a result of emotionally threatening and non-threatening words.

Twenty right-handed males participated in a tachistoscopic unilateral letter recognition task with three conditions. In the control condition, each trial consisted of three consonants that were flashed horizontally to the left or to the right visual field. In the threat and non-threat conditions, each lateral three-letter presentation was preceded by an emotionally threatening or non-threatening word presented in central fixation. Across conditions, subjects identified more letters correctly in the right visual field than in the left visual field. The concurrent presentation of threatening words resulted in a selective enhancement of left visual-field performances. The concurrent presentation of non-threatening words resulted in a selective right visual-field enhancement. Our conclusion is that threatening stimuli prime the right hemisphere and can alter predicted laterality patterns.

Animals↗
PubMed1991

Doppler echocardiographic evaluation of pulmonary artery pressure in chronic obstructive pulmonary disease. A European multicentre study. Working Group on Noninvasive Evaluation of Pulmonary Artery Pressure. European Office of the World Health Organization, Copenhagen.

The feasibility, reproducibility and reliability of Doppler echocardiography in evaluation of pulmonary artery pressure in patients with chronic obstructive pulmonary disease (COPD) were determined in a multicentre study. In 100 COPD patients with mean pulmonary artery pressure ranging from 10 to 62 mmHg at cardiac catheterization, pulmonary pressure estimation was attempted by four Doppler echocardiographic methods. These methods comprised the calculation of transtricuspid and transpulmonary pressure gradients from Doppler-detected tricuspid or pulmonary regurgitation, the evaluation of right ventricular outflow tract velocity profiles with the measurement of right ventricular systolic time intervals and the measurement of the right ventricular isovolumic relaxation time. In 98 (98%) patients at least one of the methods could be employed. A tricuspid regurgitation jet was detected in 47 (47%) patients but its quality was adequate for measurement in 30 (30%). Pulmonary regurgitation jet velocity was measured only in five cases. The standard error of estimate in testing intra- and interobserver reproducibility of Doppler systolic time intervals was less than 5%. The predictive value of right ventricular outflow tract acceleration time less than 90 ms in the identification of patients with mean pulmonary artery pressure greater than 20 mmHg was 80%. Of Doppler echocardiographic data, best correlations with mean pulmonary artery pressure were found for the transtricupid gradient (r = 0.73, SEE = 7.4 mmHg), for the right ventricular acceleration time (r = 0.65, SEE = 8 mmHg) and right ventricular isovolumic relaxation time (r = 0.61, SEE = 8.5 mmHg).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Pulmonary embolism in the coronary care unit].

Massive pulmonary embolism (MPE), as seen in cardiac care units (CCU), is almost invariably characterized by severe obstruction of the pulmonary vasculature and/or a background of poor cardiorespiratory conditions, all contributing their share to a grave overall situation, often compounded by cardiogenic shock and not exceptionally eventuating in cardiocirculatory arrest (CCA). In such circumstances, echocardiography offers both direct and indirect diagnostic elements that may help, among other things, differentiate pulmonary embolism from acute myocardial infarction--the latter not always easily identified, also in view of its possible occurrence in association with MPE. Conversely, some problems are still open concerning the meaning and treatment of right-sided intracavitary thrombus formations revealed by echocardiography. Among less familiar hemodynamic aspects we must consider right-sided pulsus alternans and the so-called ventricularization of pulmonary pressure curves--a phenomenon to be viewed with caution because of possible modifications imputable to the recording system. Bedside pulmonary angiography, now generally feasible with standard CCU equipment, may readily diagnose or rule out MPE in situations where an angiography room is not available or momentarily not accessible. Numerous personal anatomoclinical observations bear witness to the role of electromechanical dissociation (EMD) as a cause of CCA in patients with MPE. Such dissociation may prove at least temporarily reversible, especially in cases not featuring bradycardia and showing narrow QRS complexes; the concurrent administration of fibrinolytic agents along with cardiopulmonary resuscitation may prove successful while it does not seem to invite important hemorrhagic complications.

Angiography↗