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Biomedical subjects

M Morpurgo

Publications and source records attributed to M Morpurgo.

At least 55 records · Page 3Linked to original sources
PubMed1991

Myocardial perfusion in Friedreich's ataxia: assessment by dipyridamole thallium-201 imaging.

In order to assess myocardial perfusion in patients with Friedreich's ataxia, we carried out dipyridamole-thallium imaging in 13 cardiologically asymptomatic patients (aged 16 to 39; mean age 24) with various degrees of left ventricular hypertrophy; all showed electrocardiographic ST and/or T wave abnormalities before scintigraphy. After dosing with dipyridamole-201 thallium, we found: a completely reversible perfusion defect in the apical and a partially reversible defect in the posterolateral wall of the left ventricle in 1 case; a partially reversible perfusion defect in the anterior and posterior walls of the left ventricle in 1 case; and a persistent anterolateral perfusion defect in 1 case. The remaining 10 patients showed no scintigraphic abnormalities. The fact that only 1 of our patients showed a completely reversible perfusion defect, possibly consistent with regional myocardial ischemia, suggests that ischemia does not play a major role in the pathogenesis of the cardiac involvement in Friedreich's ataxia.

Adolescent↗
PubMed1991

[Non-invasive methods for determining the pulmonary blood pressure using ultrasonics in patients with chronic respiratory diseases].

Ultrasound techniques and especially Doppler echocardiography offer several approaches to non-invasive assessment of pulmonary arterial pressure. The method based on the measurement of the velocity of the jets of tricuspid or pulmonary regurgitation is the most straightforward one, in most cases allowing for reliable quantitative assessment of pulmonary hypertension and thus should be applied as a method of choice whenever possible. Unfortunately, its application in patients with lung hyperinflation is limited by topographic factors. Short acceleration time of flow velocity in the right ventricular outflow tract (AcT less than 70-75 msec), especially accompanied by midsystolic deceleration occurring at end-expiration, is a strong evidence of severe pulmonary hypertension. Long AcT (above 115-120 msec) is virtually diagnostic of normal pulmonary arterial pressure. If high speed Doppler tracings of both pulmonary and tricuspid valve flow are available right ventricular isovolumic relaxation time may be used for estimation of pulmonary systolic pressure. However, the elaboration of the laboratory's own regression formula rather than application of Burstin nomogram seems more advisable in such cases. The future of non-invasive assessment of pulmonary hemodynamics will depend on the reliability to monitor acute and chronic changes not only in pulmonary arterial pressure, but also in flow and resistance. At present, echocardiography should be considered as a good screening test allowing also to stratify moderate and severe pulmonary hypertension. The exact assessment of pulmonary hemodynamics, especially in patients with chronic respiratory disease, when needed for important therapeutic decisions, should in most cases rely on right heart catheterization.

Blood Pressure Determination↗
PubMed1990

[Progression of cardiopathology in Friedreich ataxia: clinico-instrumental study].

Clinical, electrocardiographic and echocardiographic 5-year follow-up was performed in our institution on 61 patients with Friedreich's ataxia. Cardiac failure was evident in 5% of the patients, and was the most common cause of death. Cardiac arrhythmias, most commonly supraventricular in origin, usually occurred together with the onset of cardiac failure and in 1 case resulted in sudden death. ST-T abnormalities were present in 91% of the cases, and were independent from other clinical parameters. On the contrary, pseudonecrotic (5%) and right ventricular hypertrophy pattern were associated with a poor prognosis. Left ventricular hypertrophy was evident at the echocardiogram in 75% of cases and remained unchanged throughout the entire follow-up period. In 1 case left ventricular hypertrophy turned to dilative cardiomyopathy. Autopsy was performed in 2 out of 4 decreased patients and revealed massive interstitial fibrosis with cellular degeneration in the absence of coronary lesions.

Adolescent↗
PubMed1989

Non-invasive assessment of pulmonary arterial hypertension in chronic lung disease (WHO study).

Methods for prolonged recording of pulmonary artery pressure (PAP) in unrestricted subjects have been developed. Although relatively safe, cardiac catheterization is invasive and expensive. By combining several non-invasive methods (NIM) aiming to predict the level of PAP, the extent of right ventricular (RV) hypertrophy and the degree of RV dysfunction, respectively, one can foresee the existence or the absence of pulmonary arterial hypertension (PAH), but not the precise level of PAP. This result is satisfactory in order to screen "at risk" populations, but not to obtain occasional readings from a patient with chronic obstructive lung diseases. In this type of patient PAP increase is not very marked and lung hyperinflation reduces the sensitivity of some NIM and precludes the correct execution of others. Increasing the number of investigation entails an increase of the cost-benefit ratio. NIM may help select risk patients for catheterization for suspected exercise PAH or mild PAH at rest. Some doubts exist as to whether the same methods can be used for exploring the effects of treatment in patients with chronic lung disease.

Echocardiography, Doppler↗
PubMed1988

Haemodynamic requirements for an ideal pulmonary vasodilator.

An ideal vasodilator should be selective for the pulmonary vascular bed, thus minimizing side-effects from reduced systemic resistance. It must achieve not only a drop in pulmonary vascular resistance but also a marked decrease in pulmonary arterial pressure. The ideal drug should increase cardiac output and pulmonary venous oxygen saturation. An increase in oxygen delivery to the peripheral tissues should be achieved at a lower right ventricular afterload both at rest and during exercise. Right ventricular function should be improved. The effects of vasodilator therapy should be so marked that it should be possible to follow them non-invasively by radionuclide methods and exercise tolerance tests. The aim of vasodilator therapy is a regression of pulmonary hypertension and of right ventricular hypertrophy, an improved quality of life, and above all a longer survival.

Blood Pressure↗
PubMed1988

Biventricular function in Friedreich's ataxia: a radionuclide angiographic study.

The systolic and diastolic function of both ventricles was assessed by radionuclide angiography in 21 patients with Friedreich's ataxia and hypertrophic cardiomyopathy. The indices of systolic function of the two ventricles and those of diastolic function of the right ventricle were generally normal. But in patients with Friedreich's ataxia the time to peak filling rate divided by the diastolic time of the left ventricle was significantly larger than normal. The increase correlated with the heart rate (r = 0.79) and this suggests an alteration in the timing of ventricle filling that is more evident at high heart rates. Movement of the left ventricle was little impaired; however, in 48% of the patients with Friedreich's ataxia the right ventricle showed evidence of hypokinetic segments. Because there is a tendency for congestive heart failure to develop in patients with Friedreich's ataxia, this hypokinesis of the right ventricle should be monitored at follow up.

Adolescent↗
PubMed1988

Progression of hypertrophic into a dilated left ventricle in Friedreich's ataxia.

The authors describe the case of a girl who developed Friedreich's ataxia at, approximately, the age of 7, with evidence of cardiac involvement being detected by electrocardiography and echocardiography at a later date. Cardiac function was moderately impaired and remained unchanged for a number of years, during which a picture of hypertrophic left ventricle seemed to be firmly established. Later still, however, the cardiac situation shifted gradually toward a hypokinetic form of the disease, with a progressive thinning of the interventricular septum and posterior wall of the left ventricle, associated enlargement of the ventricular chambers and increasingly severe hypokinesia leading to repeated episodes of heart failure.

Cardiomyopathy, Dilated↗
PubMed1988

[Which moments in the respiratory cycle have the most influence on right ventricular dynamics?].

The performance of the right heart during respiratory activity has mostly been studied in terms of changes in flow and pressure in pulmonary circulation. The aim of this study was to identify which moments of the respiratory cycle exert the greatest influence on right ventricular dynamics. Thus, the behaviour of the right ventricular systolic time intervals and pulmonary artery pressures, expressed both as intravascular (Piv) and transmural (Ptm), were investigated to this end. Investigations were carried out on 10 anesthetized spontaneously breathing beagle dogs using high-fidelity pressure transducers (MPC 500, Millar Instr.) and by making use of a computerized system of signal recording and analysis. Changes in right ventricular systolic time intervals were evident during transition from inspiration to expiration and at the beginning of expiration. In fact, compared to spontaneous post-expiratory pause values, the so-called Rapid Ejection and Slow Ejection Phases, and therefore the Total Ejection Period, were significantly shortened (p less than 0.01 for both) only at early expiration, whereas during the same phase of the respiratory cycle the Isovolumetric Contraction Time and the total Pre-ejection Period were significantly prolonged (p less than 0.01 for both). During the transition from inspiration to expiration, the right ventricular systolic "plateau" very often presented an ascending slant, i.e., reaching maximum pressure in late instead of early systole, as usually observed in the other moments of the respiratory cycle.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Echocardiographic evaluation of verapamil in Friedreich's ataxia.

Nine patients with hypertrophic cardiomyopathy associated with Friedreich's ataxia were treated with the calcium antagonist verapamil, which is known to reduce myocardial hypertrophy and improve diastolic function in patients with idiopathic hypertrophic cardiomyopathy. Daily oral doses of 7 mg/kg were given for a mean (SD) of 24 (8) months. M mode echocardiography performed at the start of the study and at the end of follow up showed no significant difference between the treated group and an untreated control group of nine patients. Verapamil produced no changes in left ventricular wall thickness, mass index, left ventricular internal diameter, fractional shortening, peak normalised lengthening rate, peak rate of septal and posterior wall thinning, and time from minimum ventricular cavity dimension to mitral valve opening. Myocardial calcium overload has been suggested as a cause of cardiac disease in Friedreich's ataxia; however, verapamil had no beneficial effect on these patients with established myocardial hypertrophy.

Adolescent↗
PubMed1985

[An unusual cause of arterial and venous pulmonary hypertension].

A 49 year old woman with syphilis of recent onset was repeatedly admitted to the hospital on account of recurrent dyspnoea and hemoptysis. The symptoms and radiological signs indicated the presence of a "cardiac lung". The ECG disclosed right ventricular overload which was confirmed by echocardiography. The left heart was normal, not only on echocardiography but also on cardiac catheterization, which documented severe pulmonary hypertension, partly precapillary, partly postcapillary. The presence of chronic lung congestion in the absence of pathological findings pertaining to the left heart lead to the diagnosis of pulmonary venous occlusive disease. However, pulmonary angiography showed notable and widespread arterial amputations which are not present in this syndrome. Autopsy provided the correct diagnosis: sclerosing mediastinitis localized at the hilum with prevalent involvement of both arterial and venous pulmonary vessels.

Female↗