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P Buonamici

Publications and source records attributed to P Buonamici.

25 records · Page 2Linked to original sources

Preliminary evaluation in humans of Tc-99m-Q3, a new tracer for myocardial perfusion imaging.

Trans[99m-Tc-acac2en(TMPP)2]+, where acac2en is N,N'-ethylenebis(acetylacetone iminate) and TMPP is tris-(3 methoxy propyl) phosphine, (shortened Q3) is a new lipophilic Technetium-99m-labelled compound developed for myocardial perfusion imaging. Encouraging data were obtained in the experimental animal. Aim of this study was to perform a preliminary evaluation of Q3 imaging in humans and to compare it with a reference coronary flow tracer such as Tc-99m microspheres. Eight coronary artery disease patients (males, age 58.5 +/- 10 years) were studied. They were injected with 740 MBq of Q3 and single photon emission computed tomography (SPECT) was performed 90 minutes later. After 3 days 740 MBq of Tc-99m microspheres were injected through a pig-tail catheter in the left ventricle (LV), during heart catheterization, and SPECT was acquired 60 minutes later. Q3 images showed a good target/background activity ratio:LV wall/LV cavity = 4.16 +/- 1.2; myocardium/lung = 3.95 +/- 0.52; the related values with microspheres were 6.36 +/- 2.48 (N.S.) and 4.57 +/- 1.07 (N.S.), respectively. Q3 was cleared by the liver and at the moment of SPECT collection the myocardium/liver activity ratio was 1.54 +/- 0.32. The Q3 LV lateral wall/septum activity ratio showed a good correlation with the corresponding microspheres ratio: Q3 ratio = 0.027 + 0.95 microspheres ratio, r = 0.89, SEE = 1.12, p < 0.005.

Coronary Disease↗

[Myocardial scintigraphy using 99m-technetium pyrophosphate in the diagnosis of acute myocardial infarct. Comparison of planar and tomographic imaging].

The aim of the study was to compare the effectiveness of planar and single photon emission computed tomography (SPECT) imaging with 99mTc-pyrophosphate in the verification of acute myocardial infarction. The study was performed on 39 patients (26 males, 13 females) aged between 41-76 years (mean 61 +/- 9) admitted to CCU for acute myocardial infarction. Patients underwent planar and SPECT imaging using a double-head-camera with a 360 degrees rotation arc within 6 days of admission. Planar images were obtained in three standard projections (anterior, LAO 45 degrees, LAO 75 degrees) with acquisitions of 500000 counts each. To obtain SPECT images ninety projections, each lasting 20 seconds, were taken; subsequently images reconstruction was performed using an iterative algorithm. Positive planar images were found in 21 out of 39 patients; SPECT images were positive in 33 patients. In "Q wave" myocardial infarctions planar images were positive in 13 out of 15 patients, whereas SPECT images were positive in all subjects; in "non-Q wave" myocardial infarctions planar images were positive in 6 out of 22 patients whereas SPECT images were positive in 16 patients (p less than 0.005); in 2 patients with left bundle branch block both planar and SPECT images were positive. A bidimensional echocardiogram was carried out on 38 patients: an alteration of left ventricular regional wall motion was present in 30 subjects; in one patient diffuse hypokinesia was present.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Chronobiological study of ischemic attacks in angina pectoris at rest].

The aims of this study were to determine if the hourly distribution of ischaemic episodes differed as regards ST segment elevation or ST segment depression during ischaemic attacks and differed as regards the degree of coronary atherosclerotic involvement. Twenty-four in-patient drug free subjects with angina at rest underwent ECG continuous Holter monitoring for periods varying from 24 to 168 hours. Four groups of patients were identified: group 1A: 6 patients with ST elevation and 0-1 vessel disease; group 1B: 6 patients with ST elevation and 2-3 vessel disease; group 2A: 3 patients with ST depression and 0-1 vessel disease; group 2B: 9 patients with ST depression and 2-3 vessel disease. During Holter monitoring, 301 ischaemic episodes were registered in group 1A during 576 hours; 173 episodes were registered in group 1B during 624 hours; 41 episodes were registered in group 2B during 528 hours. Using the single and population mean cosinor tests on the episodes of each group, considered as a whole, the following results were found: group 1A showed a circadian rhythm with acrophase at 4:03 a.m. (Fig. 2), group 1B showed a circadian rhythm with acrophase at 10:51 a.m. (Fig. 3), group 2A showed a circadian rhythm with acrophase at 11:15 p.m. (Fig. 5), while group 2B showed ultradian rhythms which lasted 7 and 13 hours (Fig. 6). The chronobiologic analysis of the distribution of the ischaemic attacks confirmed the existence of a circadian rhythm of ischaemic episodes in patients with ST elevation.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗

[Comparative evaluation of 3 calcium antagonist drugs in patients with stable angina of effort. Double-blind placebo-controlled randomized study].

A study was undertaken in order to compare the effects of Diltiazem, Nifedipine and Verapamil on 11 male adults (aged 44 to 70 yrs: mean age 60 yrs) affected by effort angina with a stable exercise threshold. The study was carried out according to a 4 week double-blind randomized protocol. Diltiazem (300 mg/die), Nifedipine (50 mg/die), Verapamil (400 mg/die) and placebo were administered each for 7 day periods. An ergometric test was performed on the last of each therapeutic cycle in order to evaluate the effects of the treatments. The three active drugs globally provoked an increased tolerance to physical effort with respect to placebo (p less than 0.01); no significant differences, as regards physical performance, could be detected among the three drugs. Treatment with Nifedipine significantly increased heart rate at rest (p less than 0.05), under submaximal (p less than 0.05) and maximal load (p less than 0.05), with respect to treatment with Diltiazem and Verapamil. Systolic and diastolic arterial blood pressure did not vary significantly with any of the three drugs. Rate pressure product under submaximal load (p less than 0.05) and at the end of the exercise (p less than 0.05) was higher with Nifedipine than with the other two drugs. These results show that patient response to Nifedipine is different from that to Verapamil and Diltiazem and suggest that the three drugs exert their anti ischemic effect through different mechanisms. The evaluation of individual response revealed that only one patient showed no increased tolerance to physical effort with any of the drugs.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Ambulatory electrocardiography in the evaluation of anti-ischemic therapy].

The role of ambulatory ECG monitoring (AEM) in the evaluation of anti-ischemic therapy is different in relation to the pathogenesis of myocardial ischemia. In spontaneous angina, caused by a primary reduction of coronary blood flow, the AEM represents the most efficient method to evaluate treatment results. In fact ECG monitoring permits the real evaluation of quantitative therapeutic effects, that is the reduction of the number of ischemic episodes or their abolition; besides it gives information about the treatment effects on the ischemic episodes duration, the ST dislocation entity, the incidence of asymptomatic episodes, the presence of ventricular arrhythmias and the possible different effect of treatment on the ischemic episodes characterized by ST elevation or depression. In patients undergoing anti-ischemic therapy AEM allows to study the temporal course of drug effect in order to achieve the best personal dosage schedule. While no doubt exists about Holter usefulness in the short-term control of the treatment, further data are needed to verify the role of AEM in predicting long-term efficacy of therapy. The role of Holter monitoring in the control of treatment efficacy in effort angina is more limited. However this method can be useful in those patients whose stress test shows only a partial protection in spite of anti-ischemic treatment: in these subjects the application of AEM permits to verify the presence of asymptomatic ischemic episodes that can occur either at rest or because of minimal activity.

Angina Pectoris↗

Head-to-head comparison of exercise stress testing, pharmacologic stress echocardiography, and perfusion tomography as first-line examination for chest pain in patients without history of coronary artery disease.

BACKGROUND: To overcome the relatively low accuracy of exercise stress testing (EST) in detecting coronary artery disease (CAD), both echocardiography and perfusion scintigraphy have been evaluated in conjunction with pharmacologic stress, but there is still uncertainty of the relative value of these tests as possible first-line examinations for suspected CAD. This study evaluated the accuracy of EST, dipyridamole and dobutamine stress echocardiography (DIP-ECHO, DOB-ECHO), and dipyridamole and dobutamine technetium 99m sestamibi tomography (DIP-MIBI, DOB-MIBI) for the detection of CAD in patients evaluated for the first time because of chest pain. METHODS AND RESULTS: Sixty patients underwent EST, DIP-ECHO, DOB-ECHO, DIP-MIBI, and DOB-MIBI. Echocardiographic images were acquired simultaneously with sestamibi injections, and the scintigraphic images were collected 1 hour later. Coronary angiography was performed within 15 days. Out of 33 patients with significant (>70%) coronary stenoses, 19 (58%) were correctly identified by EST, 18 (55%) by DIP-ECHO, 20 (61%) by DOB-ECHO, 32 (97%) by DIP-MIBI, and 30 (91%) by DOB-MIBI (p < 0.005 for MIBI vs EST and ECHO). The specificity of EST was 67% (p < 0.05 vs ECHO and MIBI), 96%, 96%, 89%, and 81%, respectively. Of the 62 stenotic coronary arteries, 20 (32%) were correctly identified by DIP-ECHO, 24 (39%) by DOB-ECHO, 48 (77%) by DIP-MIBI, and 45 (73%) by DOB-MIBI. The sensitivity of the imaging techniques in predicting the presence of multivessel disease was 14% and 29% for DIP and DOB-ECHO compared with 48% and 57% for DIP and DOB-MIBI. CONCLUSIONS: Our results confirm the limited reliability of EST in detecting CAD and the good diagnostic value of DIP and DOB-MIBI. Conversely, the lower sensitivity and the poorer capability to recognize multivessel CAD do not support the role of either DIP or DOB-ECHO as first-line examination for suspected CAD.

Chest Pain↗