PubMed Health⌕ Search

Biomedical subjects

D Antoniucci

Publications and source records attributed to D Antoniucci.

64 records · Page 4Linked to original sources
PubMed1988

[Study of myocardial perfusion at rest using technetium Tc 99m methoxy-isobutylisonitrile: comparison with labeled microspheres and thallium 201].

In order to evaluate the potential usefulness of 99m technetium (Tc)-methoxy-isobutyl-isonitrile (MIBI) as a myocardial perfusion tracer in man, its myocardial distribution at rest was compared with that of 201thallium (TI). Perfusion images obtained with 99mTc-labelled microspheres, whose myocardial distribution is exclusively coronary flow dependent, were used as reference. The study was performed on twelve patients (10 males and 2 females, mean age 55.4 +/- 6.4) with suspected effort angina and without a history of previous myocardial infarction. In the space of two weeks patients underwent rest and exercise 99mTc-MIBI myocardial scintigraphy, exercise-redistribution 201TI myocardial scintigraphy, 99mTc-labelled microsphere scintigraphy after microsphere injection in the left ventricle at rest during catheterization before performing left ventriculography and coronary angiography. The comparison with microsphere distribution was limited to rest 99mTc-MIBI scintigraphy and redistribution 201TI images. Single photon emission tomography (SPECT) was employed. SPECT was performed using a double-head Rotacamera with a 360 degrees rotation arc. Ninety projections of 20 seconds each were acquired; subsequently image reconstruction was performed using an iterative algorithm. To evaluate regional perfusion the left ventricular wall was divided into 18 segments; the uptake pattern of each segment was graduated according to a qualitative score (0: severe defect; 1: moderate defect; 2: normal uptake). The quality of tomographic myocardial 99mTc-MIBI and 99mTc-microspheres images was higher than that of 201TI tomograms in account of the different physical characteristics of the two radionuclides.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1981

[Echocardiographic features of the St. Jude Medical valve prosthesis (author's transl)].

The St. Jude Medical (SJM) valve is a new low-profile bileaflet prosthesis with central flow, low transvalvular gradients and low thrombogenicity. Echocardiographic features of 212 correctly functioning SJM prostheses implanted in 160 patients were studied. A SJM prosthesis echogram is unique for the presence of echoes from two hemidisks that come together when the valve opens and separate when the valves close. The movement of the two hemidisks is not always synchronous. A little asynchronism (less than 0.01 sec.) is possible as the valve begins to open. More pronounced asynchronisms are recorded in prostheses implanted in mitral position and specially when the R-R interval is longer than 1 sec. In this case partial or definitive mid-diastolic closure of the posterior hemidisk is frequent. On the contrary the anterior hemidisk always remains in maximum open position for the complete duration of the diastole. Opening and closing velocities of the valve are extremely variable. However, opening velocity, independent of where the prosthesis is implanted, is always slower than the closing one. The opening valve interval is 0.06-0.10 sec. in mitral position and 0.03-0.05 sec. in aortic position. Echocardiography is a very useful diagnostic tool for evaluating the efficiency of SJM prosthesis. Data obtained from echograms of prostheses implanted in mitral position prove that the inertia of the valve hemidisks is similar to that of natural valve leaflets.

Aortic Valve↗
PubMedDate not supplied

Predictive value of sequential testing in screening for silent myocardial ischemia in asymptomatic middle-aged men (the ECCIS Project).

The accuracy of sequential testing in the noninvasive diagnosis of coronary artery disease has been established in the symptomatic clinical populations, while little is known about its value when applied to low prevalence groups, such as totally asymptomatic men. To evaluate the accuracy of noninvasive sequential testing in the diagnosis of silent myocardial ischemia, data were collected from exercise electrocardiogram, 201Tl perfusion scintigraphy and radionuclide angiography for 62 totally asymptomatic middle-aged men who underwent coronary arteriography because they were positive for two or more markers of myocardial ischemia as determined by a diagnostic screening of a nonbiased population consisting of 4,842 presumably healthy men aged 40-59 years (the ECCIS Project). The predictive value of serial testing procedures for significant coronary artery obstruction was 35%. Predictive values of an abnormal electrocardiogram associated with either an abnormal 201Tl scintigram, an abnormal isotopic ventriculography, or both were 33, 38 and 31%, respectively. In asymptomatic middle-aged men, there is at least a 50% likelihood that an abnormal radionuclide test is a false-positive result, and the positive predictive value is not enhanced by the concordance of an abnormal 201Tl scintigraphy with an abnormal isotopic ventriculography. Thus, the application of noninvasive sequential testing in screening for asymptomatic coronary artery disease is limited by its low predictive value in accordance with the Bayesian probability theory.

Adult↗