Short bowel disease after emergency surgery for massive intestinal infarction. A case report and review of the literature.

Mesenteric ischemia is an infrequent diagnosis, although it carries substantial morbidity and mortality. In adults, the massive resection of small bowel leaving less than 150 cm of intestine results in malabsorption and diarrhoea and defines the short bowel syndrome (SBS). In this report, we present a case of emergency surgery with a near total enterectomy due to superior mesenteric ischemia with a long time of survival. KEY WORDS: Case report, General surgery, Mesenteric ischemia, Small intestine.

Chemotherapy-Induced Neurotoxicity: Evidence of a Protective Role of CC Homozygosis in the Interleukin-1ß Gene-511 C>T Polymorphism.

We hypothesized that the IL-1ß-511 C>T polymorphism could be associated with the development of neurotoxicity and that it could be a possible biomarker to rate the risk of occurrence of neurotoxicity in cancer patients. Genomic DNA was extracted from 85 cancer patients: 49 received systemic chemotherapeutic treatment (CHT) and 36 patients did not receive it (No-CHT). All subjects were genotyped for the functionally active polymorphisms of IL-1ß-511 C>T. We estimated neurotoxicity with the evaluation of neurological deficits. CHT patients showed erythrocytopenia, neurological deficit and a slight lowering of cognitive performance. The subgroup of patients carrying the CC genotype of the IL-1ß-511 C>T gene showed lesser neurological deficits. In the context of cancer treatment, we suggested the potential value of IL-1ß-511 C>T as genetic biomarkers to identify patients with higher risk to develop neurological deficits.

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.

Prognostic implications of Tc-99m sestamibi viability imaging and subsequent therapeutic strategy in patients with chronic coronary artery disease and left ventricular dysfunction.

OBJECTIVES: The aim of the study was to verify the prognostic implications of viability detection using baseline-nitrate sestamibi imaging in patients with left ventricular (LV) dysfunction due to chronic coronary artery disease (CAD) submitted to different therapeutic strategies. BACKGROUND: The prognostic meaning of preserved viability in these patients is still debated. Sestamibi is increasingly used for myocardial perfusion scintigraphy and is being accepted also as viability tracer, but no data are available about the relationship between viability in sestamibi imaging, subsequent treatment, and patient's outcome. METHODS: Follow-up data were collected in 105 CAD patients with LV dysfunction who had undergone baseline-nitrate sestamibi perfusion imaging for viability assessment and had been later treated medically (group 1), or submitted to revascularization, which was either complete (group 2A) or incomplete (group 2B). RESULTS: Eighteen hard events (cardiac death or nonfatal myocardial infarction) were registered during the follow-up. A significantly worse event-free survival curve was observed in the patients of group 1 (p < 0.0002) and group 2B (p < 0.03) compared to those of group 2A. Using a Cox proportional hazard model, the most powerful prognostic predictors of events were the number of nonrevascularized asynergic segments with viability in sestamibi imaging (p < 0.003, risk ratio [RR] = 1.4), and the severity of CAD (p < 0.02, RR = 1.28). CONCLUSIONS: Viability detection in sestamibi imaging has important prognostic implications in CAD patients with LV dysfunction. Patients with preserved viability kept on medical therapy or submitted to incomplete revascularization represent high-risk groups.

Single photon emission computed tomography with technetium-99m hexakis 2-methoxyisobutyl isonitrile in acute myocardial infarction before and after thrombolytic treatment: assessment of salvaged myocardium and prediction of late functional recovery.

Single photon emission computed tomography (SPECT) with technetium-99m hexakis 2-methoxyisobutyl isonitrile was investigated as a method to evaluate the results of intravenous thrombolytic treatment in 14 patients (11 men and 3 women) with acute myocardial infarction admitted to the coronary care unit within 4 h of the onset of symptoms. All patients received an injection of 740 MBq of the tracer before starting the thrombolytic therapy, and isonitrile tomography was performed 3 to 4 h later. The tomographic study was repeated 5 days after the acute event. The results of thrombolytic treatment were independently evaluated taking into account the clinical, electrocardiographic (ECG) and enzymatic data and the findings of left ventricular and coronary angiography. Furthermore, all patients were studied with two-dimensional echocardiography on admission, 5 days later and 1 month later. The site and extent of the perfusion defects on admission scintigraphy were consonant with the ECG and echocardiographic findings. A good correlation could be established between the 5 day scintigraphic estimate of infarct dimension and the enzymatic infarct size (r = 0.907, p less than 0.00002). The comparison between pre- and postthrombolytic treatment images enabled the identification of successful and unsuccessful reperfusion even in patients whose other noninvasive findings were inconclusive. Finally, the reduction in defect size predicted late functional improvement that was demonstrated by echocardiography performed 1 month later (r = 0.89, p less than 0.00005). The results of the study suggest the feasibility and the possible usefulness of isonitrile tomography in demonstrating the presence and size of myocardial damage and in assessing the extent of myocardial salvage after thrombolytic therapy in acute myocardial infarction.

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)

Comparison of baseline-nitrate technetium-99m sestamibi with rest-redistribution thallium-201 tomography in detecting viable hibernating myocardium and predicting postrevascularization recovery.

OBJECTIVES: This study aimed to define the optimal criteria for detecting viable myocardium with rest-redistribution thallium-201 (Tl-201) or baseline-nitrate technetium-99m (Tc-99m) sestamibi single-photon emission computed tomography (SPECT) using discriminant analysis and to compare the accuracy of the two tracers in predicting postrevascularization recovery. BACKGROUND: Rest-redistribution Tl-201 imaging is currently used for detection of myocardial viability, but the optimal variables for territory classification have not yet been defined. Although Tc-99m sestamibi is reportedly less effective than Tl-201, its reliability can be increased by injecting it during nitrate infusion. METHODS: In 35 patients with left ventricular (LV) dysfunction, tracer activity within asynergic coronary territories was quantified on rest and redistribution Tl-201 and baseline and nitrate Tc-99m sestamibi SPECT. Asynergic territory viability was evaluated on the basis of the postrevascularization functional outcome. RESULTS: Percent activity within asynergic territories was significantly influenced by their viability (p < 0.005) and the type of acquisition (p < 0.0001) but not by the tracer used. Discriminant analysis identified redistribution Tl-201 activity and nitrate-induced Tc-99m sestamibi activity change as the two most significant predictors of postrevascularization recovery. The discriminant function defined for Tl-201, including redistribution activity and reversibility, correctly classified 38 of 56 asynergic territories, whereas that for Tc-99m sestamibi, including nitrate-induced activity change and activity in nitrate images, correctly classified 43 territories. CONCLUSIONS: Redistribution activity is more important than reversibility when differentiating viable from nonviable territories using rest-redistribution Tl-201. In Tc-99m sestamibi SPECT, nitrate-induced activity changes are particularly useful in identifying myocardial viability. Baseline-nitrate Tc-99m sestamibi SPECT appears no less effective than rest-redistribution Tl-201 in predicting postrevascularization recovery.

Using PET-CT in the restaging of primitive mediastinal B-cell lymphoma (PMBCL) after chemotherapy: which criteria should we use?

AIM: Primitive mediastinal B-cell lymphoma (PMBCL) is a relatively rare form of non-Hodgkin lymphoma (NHL), typically concerning the youngster, with an aggressive course and poor prognosis. The therapy generally consists of high dose chemotherapy followed by radiotherapy. PET-CT is used at staging, restaging after chemotherapy and after radiotherapy, or when relapse is suspected. Aim of the study was to compare different criteria in the evaluation of response to chemotherapy in this setting. METHODS: Thirty-eight patients with PMBCL (15 M, 23 F, median age 33 yrs [range 18-79]), all treated with chemo-immunotherapy and radiotherapy, who had undergone baseline (b-PET) and end of chemotherapy (f-CHT-PET) 18F-FDG-PET-CT scans at our institution between July 2004 and September 2014 were retrospectively re-evaluated; the median follow-up was 42 months (range 4-109), at which 4/38 (11%) had died, 5/38 (13%) were in partial response (PR) and 29/38 (76%) were in complete response (CR). The primary endpoint was progression-free survival (PFS), while the secondary one was overall survival (OS), according to the Cheson criteria. SUV max of the mediastinal disease mass at staging, of the residual mass at CT after chemo-immunotherapy, SUV max of the liver and of the mediastinal blood pool (MBP) were calculated for all patients. RESULTS: In our population, we observed that: 1) visual criteria performs better when positivity-negativity threshold is set at point 3 of the 5-point scale (5-PS); 2) semiquantitative approach by use of Δ SUV max performs better when the threshold is set at 66% decrease: in fact, at Δ SUV max analysis with 66% decrease, 9 patients resulted positive at the test (Δ SUV max ≤66%), 29 negative (Δ SUV max >66%). CONCLUSION: In our population Δ SUV max could be working well in these patients because the baseline values are very high and very homogeneous. Our data, though limited in numerosity of patients and events, suggests that in this particular setting the use of the 5-PS reporting system could not be the best tool available; on the other hand, Δ SUV max could prove to be reliable in the evaluation of response to chemotherapy.

The Neurobiological Basis of the Distress Thermometer: A PET Study in Cancer Patients.

The objective of this study was to investigate the possible associations between the Distress Thermometer (DT) scores and the brain metabolism of structures involved in stress response. Twenty-one cancer patients were assessed using the DT, Problem Checklist and Hospital Anxiety and Depression Scale (HADS). The psychological measures were correlated with [18 F]PET-FDG brain glucose metabolism. Multiple and linear regression and binary logistic regression were run to analyse data. The DT and HADS scores illustrated that 48% of patients were distressed, 19% were depressed and 48% were anxious. Results showed that some subcortical areas activity, such as part of midbrain and of hypothalamus, was correlated with the DT scores. The Problem Checklist scores correlated with the activity of the same areas and included more regions in the limbic forebrain and brainstem. Compared with the DT and Problem Checklist, HADS-Depression scores showed a more extensive pattern of correlation with brain activity, including limbic and cortical areas. The results highlighted that the DT scores correlated with the activity of brain areas typically involved in stress response. Indeed, hypothalamus metabolism was found to be the best predictor of distressed patients.

Cardiovascular effects of brain natriuretic peptide in essential hypertension.

We evaluated the cardiovascular effects of pathophysiological plasma levels of brain natriuretic peptide in seven patients with mild to moderate essential hypertension by performing equilibrium radionuclide angiocardiography at baseline and during brain natriuretic peptide infusion at increasing doses (4, 8, 10, and 12 pmol/kg per minute for 20 minutes each). Brain natriuretic peptide induced a progressive reduction of left ventricular end-diastolic volume (from 107.5 +/- 10.3 to 89.0 +/- 11.0 mL at the end of all infusion periods) and end-systolic volume, whereas stroke volume did not show any significant change (from 64.9 +/- 5.9 to 62.7 +/- 7.8 mL). Cardiac output, arterial pressure, and peripheral vascular resistance did not change significantly. The lack of effects on systemic hemodynamics was probably due to compensatory activation of the sympathetic nervous system, as indicated by the significant increase in plasma norepinephrine levels (from 1.75 +/- 0.18 to 2.19 +/- 0.21 nmol/L), heart rate (from 68 +/- 6 to 81 +/- 6 beats per minute), peak ejection rate, and peak filling rate. These results indicate that brain natriuretic peptide, at the pathophysiological plasma concentrations reached in this study, influences cardiovascular homeostasis mainly by reducing cardiac preload.

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)

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.

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.

Rest-redistribution thallium-201 SPECT to detect myocardial viability.

UNLABELLED: Rest-redistribution 201Tl imaging is currently being used for myocardial viability detection, but the ideal parameters for territory classification have not yet been defined. The aim of this study was to define the optimal criteria for detecting viable myocardium and predicting postrevascularization recovery with rest-redistribution 201Tl SPECT. METHODS: In 29 patients with left ventricular dysfunction, tracer activity within asynergic segments was quantified on rest and redistribution 201Tl SPECT. Viability was defined by the presence of functional recovery, which was detected by comparing wall motion in baseline and follow-up echocardiography. Discriminant function analysis and receiver operating characteristic (ROC) curve analysis were used to evaluate the relationship between 201Tl data and viability. RESULTS: Of 214 dysfunctioning segments (135 a-/dyskinetic), viability was demonstrated in 115 (75 a-/dyskinetic). Both rest and redistribution 201Tl activity in these segments were significantly higher than they were in the nonviable segments (p < 0.0001). Significant (> 10%) reversibility was observed in 39% of the viable and in 36% of the nonviable segments (p = 0.81). Discriminant analysis identified redistribution activity, followed by rest activity, as the most effective predictors of functional recovery. Similar areas were found under the ROC curve for rest (0.68 +/- 0.037) and for redistribution activity (0.70 +/- 0.036) (p = 0.13). ROC curve analysis identified the optimal cutoff for redistribution activity at < 60%, with 147 of 214 (69%) segments correctly classified (sensitivity = 78% and specificity = 58%). In the subset of a-/dyskinetic segments, redistribution activity presented a significantly larger ROC curve area (0.81 +/- 0.038 compared to 0.77 +/- 0.042, p < 0.05), and 103 of 135 (76%) segments were correctly classified (sensitivity = 81% and specificity = 70%). CONCLUSION: Redistribution activity is the most important parameter to be considered in rest-redistribution 201Tl to differentiate viable from nonviable segments; rest activity is also valuable, whereas the meaning of reversibility appears limited. Cutoff values about 60% appear to give the most reasonable balance between sensitivity and specificity.

Technetium-99m-sestamibi imaging with nitrate infusion to detect viable hibernating myocardium and predict postrevascularization recovery.

UNLABELLED: We tested the relationship of nitrate-induced changes in 99mTc-sestamibi perfusion tomography and first-pass radionuclide angiocardiography (FPRNA) with postrevascularization functional recovery of asynergic territories. METHODS: Twenty-eight patients, all with prior infarction and left ventricular dysfunction, underwent two 99mTc-sestamibi rest studies: one under baseline conditions and the other with nitrate infusion. The baseline study was repeated after revascularization. Changes in global and regional perfusion and ventricular function were evaluated by perfusion tomography and FPRNA. Hibermating myocardium was identified by functional recovery in postrevascularization FPRNA. RESULTS: Eleven patients and 31 segments in 19 coronary territories had functional recovery. Nitrate-induced FPRNA changes showed poor agreement with postrevascularization modifications: kappa = 0.24, ns, for the global and kappa = 0.32, p < 0.01 for regional function. The agreement between nitrate-induced and postrevascularization perfusion changes was good both considering the patients (k = 0.57, p < 0.01) and the abnormal coronary territories (k = 0.63, p < 0.0005). The agreement of nitrate-induced perfusion changes with postrevascularization functional outcome was excellent on a patient (k = 1, p < 0.0005), and coronary territory basis (k = 0.82, p < 0.0005). Conversely, the agreement between nitrate and postrevascularization FPRNA was poor: k = 0.18, ns. CONCLUSION: These data suggest that the nitrate-induced changes in 99mTc-sestamibi perfusion imaging are useful to detect hibernating myocardium which recovers its function after revascularization.

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.

Left ventricular cavity-to-myocardium count ratio in technetium-99m-sestamibi SPECT in the detection of resting left ventricular dysfunction.

UNLABELLED: The aim of this study was to assess the value of the cavity-to-myocardium count ratio (C/M ratio) calculated in resting 99mTc-sestamibi SPECT images to identify patients with depressed left ventricular ejection fraction (LVEF). METHODS: In the 95 patients studied, the C/M ratio was calculated from the midventricular short-axis slice using regions of interest drawn in the center of the cavity and in the most active area of the ventricular wall; its value was compared with LVEF measured using two-dimensional echocardiography. RESULTS: The C/M ratio correlated with LVEF (r = 0.6, p < 0.000001) and was significantly lower in patients with abnormal LVEF than those with normal LVEF: 0.026 +/- 0.028 versus 0.125 +/- 0.093, p < 0.000001. In the entire patient population, a C/M ratio < 0.07 identified the patients with depressed LVEF with a 94% sensitivity, 71% specificity and 82% accuracy. CONCLUSION: The resting 99mTc-sestamibi C/M ratio is a useful parameter in identifying patients with depressed LVEF directly from the SPECT perfusion images.

Radionuclide angiocardiographic evaluation of the cardiovascular effects of recombinant human IGF-I in normal adults.

OBJECTIVE: IGF-I possesses specific myocardial receptors and is able to promote cardiac remodelling and even inotropic effects in both humans and other animals. In fact, reduced cardiac mass and performance are present in GH deficiency and these alterations are counteracted by recombinant human (rh) GH replacement, restoring IGF-I levels. Recently, the acute administration of 60 microg/kg rhIGF-I has also been reported to be able to improve cardiac performance evaluated by echocardiography or impedance cardiography in normal subjects. The aim of our study was to verify the effects of a subcutaneous low dose of rhIGF-I (20 microg/kg) on cardiac performance in humans. METHODS: In six healthy male adults (mean+/-S. e.m.: 35.7+/-4.3 years of age), the effects of rhIGF-I on left ventricular function evaluated by radionuclide angiocardiography and on circulating IGF-I, GH, insulin, glucose and catecholamines levels were studied. RESULTS: Administration of rhIGF-I increased circulating IGF-I (peak at +150 min vs baseline: 330.2+/- 9.6 vs 199. 7+/-8.7 microg/l, P<0.03) to levels which persisted similarly up to +180min. Neither GH nor catecholamine levels were modified by rhIGF-I administration, while insulin and glucose levels showed a slight but significant decrease. Basal left ventricular ejection fraction (61.8+/-2.0%) significantly increased at +180 min after rhIGF-I (65.3+/-2.7%, P<0.03). No change was recorded in mean blood pressure while a non-significant trend towards a reduction of heart rate was present by +120 min. CONCLUSIONS: These findings indicate that even subcutaneous administration of a low dose of rhIGF-I has acute inotropic effects as evaluated by radionuclide angiocardiography in healthy adults.

Magnetic resonance imaging of blood flow in thoracic vessels of patients with impaired left ventricular function.

In order to test the ability of magnetic resonance (MR) in the detection of pathologic flow conditions in man, we imaged 10 normal volunteers and 10 patients with congestive heart failure (CHF) with ECG-gated MR. We used a single spin-echo sequence on a transverse plane through the main vessels of the upper chest. The analysis of the variation of the mean signal intensity vs time from the ascending aorta (AA), descending aorta (DA), and pulmonary artery (PA) of the ten normal volunteers on the TE = 30 ms images, showed a common pattern characterized by an end-diastolic intraluminal signal not present in other moments of the cardiac cycle. On the contrary, in patients with CHF, we did not observe the systolic disappearance of the intraluminal MR signal. The main difference between CHF patients and control subjects was found in the DA where an abnormally high signal intensity was present for the whole cardiac cycle. The MR imaging can offer blood flow information underlying the behavior of intraluminal signal intensity and could provide functional information in patients with heart failure.