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G Bisi

Publications and source records attributed to G Bisi.

At least 55 records · Page 3Linked to original sources
PubMed1995

[Long-term cyclic and periodic omeprazole in the prevention of recurrences of duodenal ulcer].

The aim of this study was to establish if the discontinuous assumption of omeprazole was effective to reduce the recurrence of duodenal ulcer disease as the cyclic periodical assumptions of the same drug. Consequently two different posologies, after duodenal ulcer recovery, were compared, both based on omeprazole. In the first trial 20 mg/die were administrated for the first 15 days of every month, for 1 year. In the second, the same dose were administrated for 15 days only when symptoms occurred. It was not utilised a comparison with placebo or other drugs. Symptomatic score and recurrence rate were evaluated by means of EGDS after 6 months and 1 year. In some patients were also controlled the gastrinemia. Both trials were effective in the prevention of duodenal ulcer relapse, without increasing gastrinemia. Nevertheless patients assuming omeprazole only when symptomatic, showed a greater symptomatic score. Concluding, the assumption of omeprazole only when symptoms occur is effective in the prevention of relapse but require a close relation between patients and the medical team.

Adult↗
PubMed1995

Assessment of myocardial viability after thallium-201 reinjection or rest-redistribution imaging: a multicenter study. The Italian Group of Nuclear Cardiology.

UNLABELLED: To establish the real nature of 201Tl defects in the assessment of myocardial viability (e.g., fixed versus reversible), 201Tl reinjection was evaluated in a multicenter trial involving 402 consecutive patients with ischemic heart disease and exercise 201Tl defects. METHODS: Twelve hospitals, using the same type of gamma camera and computer software, adopted one of the two most widely used reinjection protocols. In 230 patients (Group A), reinjection was performed immediately after stress-redistribution planar imaging; in 172 patients (Group B), reinjection was performed on a separate day and followed by rest-redistribution imaging. The images were interpreted by three blinded observers in a core laboratory on a five-point qualitative scale; the reproducibility in visual scoring was excellent. RESULTS: Groups A and B had a similar prevalence of myocardial segments with abnormal uptake at stress (39%, 40%), as well as with reversible (16%, 17%), partially reversible (21%, 19%) and irreversible (63%, 64%) defects at redistribution. After reinjection, 201Tl uptake improved in 27% and 36% of both partially reversible and irreversible defects in Groups A and B. No differences were found when comparing early and delayed reinjection imaging in Group B. CONCLUSION: This study confirms the validity of 201Tl reinjection in a large, unselected population, but the discordance with stress/redistribution is less than has been previously reported for both 201Tl reinjection protocols, the prevalence of improved segments after reinjection was higher with the separate day approach.

Exercise Test↗
PubMed1994

Rest technetium-99m sestamibi tomography in combination with short-term administration of nitrates: feasibility and reliability for prediction of postrevascularization outcome of asynergic territories.

OBJECTIVES: This study investigated the role of nitrate technetium-99m sestamibi imaging in predicting the postrevascularization outcome of chronically hypoperfused asynergic territories. BACKGROUND: Rest technetium-99m sestamibi myocardial scintigraphy underestimates the presence of viable myocardium in asynergic territories. Stimulation that improves coronary blood flow could increase tracer uptake in hibernating territories. METHODS: Nineteen patients with a previous myocardial infarction and left ventricular dysfunction scheduled for revascularization underwent quantitative technetium-99m sestamibi tomography under baseline conditions and during isosorbide dinitrate infusion. Global and regional function were assessed, respectively, before and after revascularization by radionuclide angiocardiography and two-dimensional echocardiography. RESULTS: Seven patients (group A) showed postrevascularization regional function recovery, and 12 (group B) showed no significant changes. In group A, nitrate infusion induced a decrease in the extent of the global uptake defect ([mean +/- SD] -37.4 +/- 21.6% of baseline value); in group B, no change or a slight increase was observed (+5.8 +/- 8.4%, p < 0.0005 vs. group A). The nitrate-induced changes in the extent of uptake defect correlated with postrevascularization changes in ejection fraction (r = -0.94, SEE 7.6). After revascularization, 11 asynergic vascular territories showed improvement (hibernating), and 34 remained unchanged (fibrotic). With administration of nitrates, 10 hibernating territories had a decrease in the extent of uptake defect, whereas only 4 of 34 of the fibrotic territories showed a nitrate-induced uptake improvement. CONCLUSIONS: Short-term administration of isosorbide dinitrate immediately before injection of technetium-99m sestamibi increases tracer uptake in some chronically hypoperfused asynergic territories. This finding correlates with the observation of post-revascularization functional recovery. Nitrate technetium-99m sestamibi myocardial scintigraphy could be a promising method for the noninvasive detection of viable hibernating myocardium.

Coronary Angiography↗
PubMed1994

Coenzyme Q10 in essential hypertension.

This study was undertaken to clarify the mechanism of the antihypertensive effect of coenzyme Q10 (CoQ10). Twenty-six patients with essential arterial hypertension were treated with oral CoQ10, 50 mg twice daily for 10 weeks. Plasma CoQ10, serum total and high-density lipoprotein (HDL) cholesterol, and blood pressure were determined in all patients before and at the end of the 10-week period. At the end of the treatment, systolic blood pressure (SBP) decreased from 164.5 +/- 3.1 to 146.7 +/- 4.1 mmHg and diastolic blood pressure (DBP) decreased from 98.1 +/- 1.7 to 86.1 +/- 1.3 mmHg (P < 0.001). Plasma CoQ10 values increased from 0.64 +/- 0.1 microgram/ml to 1.61 +/- 0.3 micrograms/ml (P < 0.02). Serum total cholesterol decreased from 222.9 +/- 13 mg/dl to 213.3 +/- 12 mg/dl (P < 0.005) and serum HDL cholesterol increased from 41.1 +/- 1.5 mg/dl to 43.1 +/- 1.5 mg/dl (P < 0.01). In a first group of 10 patients serum sodium and potassium, plasma clinostatic and orthostatic renin activity, urinary aldosterone, 24-hour sodium and potassium were determined before and at the end of the 10-week period. In five of these patients peripheral resistances were evaluated with radionuclide angiocardiography. Total peripheral resistances were 2,283 +/- 88 dyne.s.cm-5 before treatment and 1,627 +/- 158 dyn.s.cm-5 after treatment (P < 0.02). Plasma renin activity, serum and urinary sodium and potassium, and urinary aldosterone did not change. In a second group of 11 patients, plasma endothelin, electrocardiogram, two-dimensional echocardiogram and 24-hour automatic blood pressure monitoring were determined.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Late thrombolysis in acute myocardial infarct. Demonstration of myocardial tissue salvage by the assessment of pre- and post-thrombolytic perfusion and left ventricular function].

BACKGROUND: Pre and post treatment perfusion scintigraphy with Tc-99m-sestamibi is an accurate method to evaluate the effectiveness of thrombolytic therapy in patients with acute myocardial infarction. In the present study this method was used to verify whether thrombolytic therapy performed late (6 to 24 hours) after symptoms onset was still able to produce significant salvage of jeopardized myocardial tissue. METHODS: Fifteen patients (mean age 60.9 +/- 9 years) admitted to CCU 8-23 hours (mean 13.2 +/- 4 hours) after symptoms onset of their first acute myocardial infarction were studied. Both myocardial perfusion and left ventricular function were assessed before and after thrombolysis. Myocardial perfusion was studied using Tc-99m-sestamibi Single Photon Emission Tomography (SPET) before (pre-lysis SPET), 4.4 +/- 0.9 days (post-lysis SPET A) and 32 +/- 6 days (post-lysis SPET B) after thrombolysis. Uptake defects were graded from 0 to 4 using a 20-segment scheme. Regional ventricular function was evaluated using two-dimensional echocardiography before (pre-lysis ECHO), simultaneously with post-lysis SPET A (post-lysis ECHO A) and 32 +/- 4 days after treatment (post-lysis ECHO B); asynergy was graded from 1 to 4. Global left ventricular function was estimated using gated blood pool imaging and measuring the ejection fraction (EF) 5.3 +/- 1 (GBP 1) and 32 +/- 4 days after treatment (GBP 2). Within 6-9 days of admission all patients underwent coronary angiography. RESULTS: In pre-lysis SPET all patients had uptaken defects (score range 17-52, mean 34.6 +/- 12). According to the comparison between pre-lysis SPET and post-lysis SPET A, patients were divided into two groups: 7 patients with perfusion recovery (Group I) and 8 patients with absent or minimal perfusion recovery (Group II). In Group I the mean uptaken score decreased significantly (from pre-lysis SPET 34.2 +/- 12 to post-lysis SPET A 21.7 +/- 7, p < 0.05); in Group II the uptaken score remained unchanged (from pre-lysis SPET 34.8 +/- 12 to post-lysis SPET A 33.6 +/- 12, ns). In post-lysis SPET B both groups showed a defect reduction compared to post-lysis SPET A; however, the defect score of SPET B in Group I was significantly lower than that in Group II (18.7 +/- 16 vs 30.1 +/- 10, p < 0.05). The asynergic score in pre-lysis ECHO was the same in the two groups (19.5 +/- 4); in post-lysis ECHO A no significant decrease was observed in the two groups. In post-lysis ECHO B a significant decrease was seen in Group I (14.8 +/- 5, p < 0.05 vs pre-lysis ECHO and vs post-lysis ECHO A), but not in Group II (19.8 +/- 5, ns); the asynergic score in post-lysis ECHO B was significantly lower in Group I than in Group II (p < 0.05). In GBP 1 the EF was 38% +/- 6 in Group I and 40% +/- 6 in Group II (ns). In GBP 2 a significant increase was registered in Group I (47% +/- 10, p < 0.05), whereas in Group II the EF remained unchanged (40% +/- 6, ns). Coronary angiography showed a patent infarct related vessel in all Group I patients and in 2 Group II patients (p < 0.05). CONCLUSIONS: These results show that in patients with acute myocardial infarction treated with thrombolysis late after symptoms onset it is still possible to obtain an effective reperfusion and the consequent salvage of jeopardized tissue, as demonstrated by the recovery of both regional and global left ventricular function.

Aged↗
PubMed1994

Maldistribution of regional myocardial perfusion at rest in patients with coronary artery disease and no previous myocardial infarction, evidenced by 99mTc-Sestamibi scintigraphy.

Since myocardial 99mTc-Sestamibi uptake is closely related to coronary blood flow and the tracer does not redistribute, resting perfusion defects may be observed even in viable regions supplied by vessels with severe stenosis. The incidence and the clinical significance of 99mTc-Sestamibi uptake defects at rest were investigated in 60 men with suspected coronary artery disease and no previous myocardial infarction, in a multicenter study. Of 60 patients, 12 showed normal coronary arteries and 48 significant coronary artery disease (> 50% luminal narrowing). Based on the presence or absence of tracer uptake defects at resting planar scans, the patients were divided into Group 1 (27 patients) and Group 2 (33 patients), respectively. A greater incidence of coronary artery disease (100% versus 64%, p < 0.01) and of multivessel disease (70% versus 36%, p < 0.05) was observed in patients of Group 1. All patients underwent dipyridamole (up to 0.84 mg/kg in 10 min) 99mTc-Sestamibi scintigraphy, which more frequently induced transient 99mTc-Sestamibi uptake defects in Group 1 than in Group 2 (85% versus 42%, p < 0.001). A high incidence of resting 99mTc-Sestamibi uptake defects was observed in patients without previous myocardial infarction; this identified a subset of patients with a higher prevalence of coronary artery disease and multivessel involvement and with a greater impairment of the coronary reserve, as evidenced by a dipyridamole test.

Coronary Circulation↗
PubMed1994

L-carnitine adjuvant therapy in essential hypertension.

This study was undertaken to demonstrate L-carnitine therapeutical effect in patients with essential hypertension. Two groups were tested, A and B. First group (A) was split in two subgroups, A1 and A2. Subgroup A1 included 14 patients with essential hypertension, they were treated with antihypertensive drugs and L-carnitine. Subgroup A2 included 14 patients with essential hypertension, that were treated with antihypertensive drugs only. Group B included 9 patients with essential hypertension and they were treated with L-carnitine only. Subgroup A1 patients were treated with oral L-carnitine 2 gm per day for 22 weeks; group B patients were treated with the same dose for 10 weeks. The asthenia symptom was evaluated, a resting and dynamic E.C.G. was carried out, serum triglycerides, serum total and high-density lipoprotein (HDL) cholesterol, serum sodium and potassium, serum creatinine, serum glucose and blood pressure were determined before and at the end of test in group A patients. Test procedure of group B patients included also serum evaluation of apolipoproteins A1 and B and radionuclide angiocardiography. In subgroup A1 patients extrasystoles as well as some electrocardiographic signs of minor changes of ventricular repolarization reversed or diminished, the asthenia symptom was improved significantly and triglyceride values decreased from 148 +/- 15.8 mg/dl to 121 +/- 14.3 mg/dl (p < 0.025).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Evaluation of coronary artery disease using technetium-99m-sestamibi first-pass and perfusion imaging with dipyridamole infusion.

UNLABELLED: The aims of this study were: (1) to test whether first-pass radionuclide angiocardiography (FPRNA) adds useful information to perfusion scintigraphy; and (2) to assess the relative accuracy of perfusion and functional imaging in combination with dipyridamole for the evaluation of CAD. METHODS: Thirty patients with angiographically proven CAD (17 with prior infarction) were studied on separate days at rest and with dipyridamole infusion (0.7 mg/kg over 4 min). Tomographic images were evaluated using an uptake score. Dipyridamole FPRNA was considered positive in case of stress-induced wall motion abnormality or ejection fraction decrease. RESULTS: The CAD detection rate of perfusion imaging was 100%, while that of FPRNA was 70% using wall motion criteria, 63% using ejection fraction response and 77% considering any abnormality. For CAD localization, perfusion imaging showed 76% sensitivity, 96% specificity and 82% accuracy. FPRNA results were 50%, 100% and 60%, respectively. Perfusion imaging was significantly superior to FPRNA also excluding from the analysis the infarct-related vessels. FPRNA did not identify multivessel CAD, which was correctly detected by perfusion imaging in most cases. Both techniques were more sensitive in case of > or = 90% stenosis, but the difference was more remarkable for FPRNA (sensitivity 65% versus 14%, p < 0.0005). CONCLUSIONS: Dipyridamole FPRNA did not add noteworthy clinical information to perfusion imaging regarding CAD detection and evaluation of disease extent. The main contribution of a positive FPRNA was its relation with coronary obstruction severity. These results confirm the superiority of perfusion over functional imaging in combination with coronary vasodilators.

Coronary Angiography↗
PubMed1994

Sublingual isosorbide dinitrate to improve technetium-99m-teboroxime perfusion defect reversibility.

UNLABELLED: Previous studies demonstrate perfusion defect reversibility in 201Tl reinjection imaging performed after the administration of nitrates. This study tests whether the acute sublingual administration of isosorbide dinitrate (ISDN) could improve the capability of 99mTc-teboroxime to detect reversibility in exercise-induced perfusion defects. METHODS: Ten patients with previous myocardial infarction underwent exercise, redistribution and reinjection 201Tl imaging, 99mTc-teboroxime exercise and rest scans. Following the latter, 5 mg sublingual ISDN were given, 99mTc-teboroxime was reinjected and images collected. RESULTS: The total defect score/patient in the 201Tl images was 10.5 +/- 3.1 (mean +/- s.d.), decreasing to 7.4 +/- 2.7 after redistribution (p < 0.02) and to 4.8 +/- 2.1 after reinjection (p < 0.01 versus redistribution). The total defect score in 99mTc-teboroxime exercise images was 12.7 +/- 3.1 (p < 0.05 versus 201Tl exercise), decreasing to 7.3 +/- 3.3 at rest (p < 0.01 versus exercise, NS versus 201Tl redistribution) and to 5.6 +/- 2.6 in ISDN images (p < 0.02 versus rest, p < 0.05 versus 201Tl redistribution, NS versus reinjection). Of the 44 abnormal segments in 201Tl exercise images, the redistribution scan identified 26 defects as reversible and 18 as fixed. After reinjection, 37 defects appeared reversible and only seven fixed (p < 0.005 versus redistribution). Stress-rest 99mTc-teboroxime classified 33 segments as reversible and 11 as fixed (NS versus both 201Tl protocols). After ISDN, the uptake score increased in 19 segments. Therefore, 37 were classified as reversible and seven as fixed defects (p < 0.01 versus 201Tl redistribution, NS versus 201Tl reinjection). CONCLUSIONS: Sublingual ISDN before 99mTc-teboroxime rest injection seemed to improve the tracer capability of detecting reversibility in exercise-induced perfusion defects.

Administration, Sublingual↗
PubMed1993

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↗
PubMed1993

Evaluation of 99Tcm-teboroxime scintigraphy for the differentiation of reversible from fixed defects: comparison with 201T1 redistribution and reinjection imaging.

The aim of this study was to compare 99Tcm-teboroxime and 201T1 myocardial studies with particular regard to the classification of perfusion defects as reversible or fixed. Twenty patients with a history of previous myocardial infarction and suspected effort ischaemia underwent exercise 201T1 scintigraphy with early (4 h) redistribution and reinjection scans, exercise and rest 99Tcm-teboroxime imaging and coronary angiography. Using a qualitative scoring of static planar images, the perfusion defects were classified as reversible or fixed. 201T1 and 99Tcm-teboroxime gave comparable results in the evaluation of the individual vessels (sensitivity 65%, specificity 80% and 85%, respectively). The stress-redistribution 201T1 sequence classified 45 defects as reversible and 28 as fixed, the stress-rest 99Tcm-teboroxime studies classified 47 as reversible and 26 as fixed (NS). The stress-reinjection 201T1 images, however, characterized 64 defects as reversible and nine as fixed (P < 0.005 versus 201T1 redistribution, P < 0.0005 versus 99Tcm-teboroxime rest). In conclusion, this study shows that rest 99Tcm-teboroxime and 201T1 redistribution give comparable results but that significantly more defects are classified as fixed by 99Tcm-teboroxime than by 201T1 if reinjection of the latter tracer is performed.

Humans↗
PubMed1993

Evaluation of coronary artery disease extent using 99Tcm-sestamibi: comparison of dipyridamole versus exercise and of planar versus tomographic imaging.

The aim of this study was to compare the reliability of 99Tcm-sestamibi myocardial scintigraphy for the assessment of coronary artery disease extent using two different stresses (exercise and dipyridamole) and imaging techniques (planar versus single photon emission tomography, SPET) in a patient population of 20 subjects, all also studied with coronary angiography. The agreement of exercise and dipyridamole was good for the visual uptake score (planar kappa = 0.71, SPET kappa = 0.64) and for abnormal segment detection (planar and SPET both kappa = 0.76). For the recognition of the individual diseased vessel, the results of exercise and dipyridamole planar scans were equal (sensitivity 49%, specificity 90%, accuracy 63%); those of exercise and dipyridamole SPET were also similar and were both better than the related planar data (sensitivity 79% and 74%, P < 0.005 and < 0.02, respectively, versus planar; specificity 95% and 100%; accuracy 85 and 83%, P < 0.001 and < 0.02 versus planar). Both stresses and imaging techniques were less sensitive in cases of mild (50 to 70%) obstructions. In conclusion, exercise and dipyridamole appear equally effective stresses for 99Tcm-sestamibi scintigraphy; with both of them, however, SPET allows significantly better results than planar imaging and therefore should be recommended.

Adult↗
PubMed1993

[Myocardial scintigraphy with Tc-99m-MIBI for assessing the extent and severity of coronary disease: a comparison with thallium-201 and equilibrium angiocardioscintigraphy].

BACKGROUND: The aim of this study was to compare in the same population of patients affected by coronary artery disease (CAD), the accuracy in the assessment of CAD extent and severity achieved by myocardial scintigraphy, performed using Tc-99m-MIBI with two different imaging techniques (planar and single photon emission tomography--SPECT) and using TI-201 SPECT and by equilibrium radionuclide angiography (RNV). METHODS: We studied 20 patients (18 men and 2 women, age range 42-74) without prior myocardial infarction, but with effort angina. Seven had one-vessel and 13 multi-vessel disease; coronary artery stenosis was > or = 70% and < 80% in 18 arteries and > or = 80% in 19. After therapy withdrawal, all patients underwent (in different days, within 2 weeks): SPECT exercise TI-201 myocardial scintigraphy (early and redistribution images), planar and SPECT Tc-99m-MIBI myocardial scintigraphy (exercise and rest imaging 24 hours apart) and RNV (baseline and exercise studies). RESULTS: All methods were highly sensitive for the diagnosis of CAD: TI-201 SPECT 95%, Tc-99m-MIBI planar 95%, Tc-99m-MIBI SPECT 100%, RNV 100%. For the recognition of the involvement of more than one territory (multi-vessel disease) myocardial scintigraphy with Tc-99m-MIBI SPECT was the most sensitive (92%, p < 0.05 vs Tc-99m-MIBI planar and p < 0.01 vs RNV) and accurate (75%) method, while regional wall motion analysis with RNV showed the highest specificity (100%, p < 0.02 vs TI-201 SPECT, p < 0.05 vs Tc-99m-MIBI SPECT). For the recognition of the involved vessels Tc-99m-MIBI SPECT had the highest sensitivity (89%, p < 0.02 vs Tc-99m-MIBI planar, p < 0.002 vs RNV) and global accuracy (80%), while regional wall motion analysis with RNV had the highest specificity (96%, p < 0.02 vs Tc-99m-MIBI planar and SPECT, p < 0.001 vs TI-201 SPECT). The degree of obstruction (< 80% vs > or = 80%) significantly influenced the rate of positive RNV results (7/18 vs 14/19, p < 0.05), but not those of the different myocardial perfusion studies. CONCLUSIONS: Our data show that clear differences among the tested methods are present with respect to the assessment of disease extent and severity. SPECT myocardial scintigraphy with Tc-99m-MIBI appears more accurate than the other methods for assessing the extent of CAD. RNV wall motion analysis shows a very good specificity for the recognition of multi-vessel CAD and for the detection of high grade obstructions. This encourages the efforts for studying, whenever possible, not only myocardial perfusion, but also ventricular function and regional wall motion. To this aim the collection of first-pass radionuclide angiocardiography at the moment of Tc-99m-MIBI injection could be particularly advantageous.

Adult↗
PubMed1992

[Myocardial scintigraphy with Tc-99m-teboroxime: its feasibility and the evaluation of its diagnostic reliability. A comparison with thallium-201 and coronary angiography].

BACKGROUND: Tc-99m-teboroxime is a new tracer for myocardial perfusion scintigraphy. Its more remarkable features are the high myocardial extraction fraction, which is well correlated with the coronary blood flow, and the extremely rapid myocardial washout. This makes it necessary to complete the image collection shortly after the injection; on the other hand, repeated scans can be easily performed by renewed Tc-99m-teboroxime administrations. The aim of the present study was to test the feasibility of Tc-99m-teboroxime imaging and to evaluate its accuracy by comparing it with thallium-201 (TI-201) scintigraphy and coronary angiography. METHODS: The patient population included 16 male patients (mean age 57.8 +/- 6.3 years) affected by suspect effort angina and/or with signs of exercise-induced ischemia; 12 of them had history of previous myocardial infarction. They underwent effort TI-201 and Tc-99m-teboroxime myocardial scintigraphy within 48 hours; left heart catheterization and coronary angiography were performed within 5 days. Scintigraphic images were collected in 3 planar views; each projection was divided in 3 segments, with the apical one shared by all views, for a total of 7 segments/study. Tracer uptake was qualitatively assessed and graduated according to a scoring scheme (from 0 = normal through 4 = absent uptake). RESULTS: Tc-99m-teboroxime scans could be accomplished without major problems in all subjects. The image quality was comparable to TI-201 in 8 patients and poorer in the remaining 8. Coronary angiography showed 50% obstructions in 15 patients; of them 1 subject had a normal scintigraphic pattern with both TI-201 and Tc-99m-teboroxime. The presence of previous infarction was recognized by both tracers in the 12 patients with infarct history. The number of abnormal segments and the uptake score were not significantly different in the Tc-99m-teboroxime rest and in the TI-201 redistribution images (segments: 2.8 +/- 1.4 vs 2.8 +/- 1.6; score: 5.6 +/- 4.2 vs 6 +/- 4.5). The diagnosis of effort ischemia was made in 13 patients with Tc-99m-teboroxime and in 12 patients with TI-201. The number of abnormal segments in the exercise Tc-99m-teboroxime and TI-201 myocardial scintigraphy was not significantly different (3.3 +/- 1.3 vs 3.3 +/- 1.5); on the contrary the defect score was significantly higher with Tc-99m-teboroxime than with TI-201 (9.5 +/- 4.3 vs 8.4 +/- 4.6, p < 0.03). Therefore the ischemic score (exercise defect score minus rest defect score) of Tc-99m-teboroxime was significantly higher than that of TI-201 (3.9 +/- 2.8 vs 2.4 +/- 2.2, p < 0.02). The two tracers gave comparable results in terms of recognition of patients with one-vessel or multi-vessel coronary artery disease. CONCLUSIONS: Planar myocardial scintigraphy with Tc-99m-teboroxime can be performed without major problems. In terms of clinical reliability the results are comparable to those of TI-201 scans. On the other hand, taking into account the poor image quality of Tc-99m-teboroxime scintigraphy, it is still impossible to predict its future role in the radionuclide imaging of coronary artery disease.

Adult↗
PubMed1991

Accuracy and safety of technetium-99m hexakis 2-methoxy-2-isobutyl isonitrile (Sestamibi) myocardial scintigraphy with high dose dipyridamole test in patients with effort angina pectoris: a multicenter study. Italian Group of Nuclear Cardiology.

Clinical and physiologic evidence indicates that maximal coronary vasodilation is not achieved in a large number of patients with use of the standard dose of dipyridamole (0.56 mg/kg body weight over 4 min). The feasibility, safety and accuracy of technetium-99m hexakis 2-methoxy-2-isobutyl isonitrile (Sestamibi) scintigraphy associated with intravenous high dose dipyridamole (0.56 mg/kg over 4 min followed 4 min later by an additional 0.28 mg/kg over 2 min) were evaluated in a multicenter study. Planar myocardial perfusion images were obtained at rest and after dipyridamole in 101 patients with effort chest pain and no prior myocardial infarction. High dose dipyridamole (62 patients) was used when typical chest pain or electrocardiographic (ECG) signs of ischemia, or both, did not occur during or after the standard dose (39 patients). With high dose dipyridamole, 34 patients had pain (18 patients) or ECG signs of ischemia (ST depression greater than or equal to 2 mm) (8 patients), or both (8 patients), whereas the other 28 patients had Sestamibi injection in the absence of symptoms or ECG changes. All patients underwent coronary angiography: 81 had significant coronary artery disease (greater than or equal to 50% reduction of lumen diameter) (affecting one vessel in 38, two vessels in 19 and three vessels in 24 patients) and 20 patients had normal coronary arteries. The overall sensitivity, specificity and predictive accuracy of Sestamibi scintigraphy were 81%, 90% and 83%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗