10-year follow-up of a prospective randomized trial comparing bare-metal stenting with internal mammary artery grafting for proximal, isolated de novo left anterior coronary artery stenosis the SIMA (Stenting versus Internal Mammary Artery grafting) trial

OBJECTIVES: This study was designed to compare the long-term clinical outcome of coronary artery bypass grafting (CABG) with intracoronary stenting of patients with isolated proximal left anterior descending coronary artery. BACKGROUND: Although numerous trials have compared coronary angioplasty with bypass surgery, none assessed the clinical evaluation in the long term. METHODS: We evaluated the 10-year clinical outcome in the SIMA (Stent versus Internal Mammary Artery grafting) trial. Patients were randomly assigned to stent implantation versus CABG. RESULTS: Of 123 randomized patients, 59 underwent CABG and 62 received a stent (2 patients were excluded). Follow-up after 10 years was obtained for 98% of the randomized patients. Twenty-six patients (42%) in the percutaneous coronary intervention group and 10 patients (17%) in the CABG group reached an end point (p < 0.001). This difference was due to a higher need for additional revascularization. The incidences of death and myocardial infarction were identical at 10%. Progression of the disease requiring additional revascularization was rare (5%) and was similar for the 2 groups. Stent thrombosis occurred in 2 patients (3%). Angina functional class showed no significant differences between the 2 groups. CONCLUSIONS: Both stent implantation and CABG are safe and highly effective in relieving symptoms in patients with isolated, proximal left anterior descending coronary artery stenosis. Stenting with bare-metal stents is associated with a higher need for repeat interventions. The long-term prognosis for these patients is excellent with either mode of revascularization.

Symptom-triggered vs fixed-schedule doses of benzodiazepine for alcohol withdrawal: a randomized treatment trial.

BACKGROUND: In alcohol withdrawal, fixed doses of benzodiazepine are generally recommended as a first-line pharmacologic approach. This study determines the benefits of an individualized treatment regimen on the quantity of benzodiazepine administered and the duration of its use during alcohol withdrawal treatment. METHODS: We conducted a prospective, randomized, double-blind, controlled trial including 117 consecutive patients with alcohol dependence, according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, entering an alcohol treatment program at both the Lausanne and Geneva university hospitals, Switzerland. Patients were randomized into 2 groups: (1) 56 were treated with oxazepam in response to the development of signs of alcohol withdrawal (symptom-triggered); and (2) 61 were treated with oxazepam every 6 hours with additional doses as needed (fixed-schedule). The administration of oxazepam in group 1 and additional oxazepam in group 2 was determined using a standardized measure of alcohol withdrawal. The main outcome measures were the total amount and duration of treatment with oxazepam, the incidence of complications, and the comfort level. RESULTS: A total of 22 patients (39%) in the symptom-triggered group were treated with oxazepam vs 100% in the fixed-schedule group (P<.001). The mean oxazepam dose administered in the symptom-triggered group was 37.5 mg compared with 231.4 mg in the fixed-schedule group (P<.001). The mean duration of oxazepam treatment was 20.0 hours in the symptom-triggered group vs 62.7 hours in the fixed-schedule group (P<.001). Withdrawal complications were limited to a single episode of seizures in the symptom-triggered group. There were no differences in the measures of comfort between the 2 groups. CONCLUSIONS: Symptom-triggered benzodiazepine treatment for alcohol withdrawal is safe, comfortable, and associated with a decrease in the quantity of medication and duration of treatment.

Ventricular but not atrial electro-mechanical delay of the embryonic heart is altered by anoxia-reoxygenation and improved by nitric oxide.

BACKGROUND/AIM: Excitation-contraction coupling is modulated by nitric oxide (NO) which otherwise has either beneficial or detrimental effects on myocardial function during hypoxia-reoxygenation. This work aimed at characterizing the variations of electromechanical delay (EMD) induced by anoxia-reoxygenation within the developing heart and determining whether atrial and ventricular EMD are modulated by NO to the same extent. METHODS: Hearts of 4 or 4.5-day-old chick embryos were excised and submitted in vitro to normoxia (45 min), anoxia (30 min) and reoxygenation (60 min). Electrocardiogram and atrial and ventricular contractions were simultaneously recorded throughout experiment. Anoxia-reoxygenation-induced chrono-, dromo-and inotropic disturbances and changes in EMD in atrium (EMDa) and ventricle (EMDv) were investigated in control hearts and in hearts exposed to 0.1, 1, 10, 50 and 100 microM of DETA-NONOate (a NO donating agent) or to 50 microM of L-NAME (a NOS inhibitor). RESULTS: Under normoxia, heart rate, PR interval, ventricular shortening velocity, EMDa and EMDv were similar in control, L-NAME-treated and DETA-NONOate-treated hearts. Under anoxia, cardiac activity became markedly erratic within less than 10 min in all groups. At the onset of reoxygenation, EMDv was increased by about 300% with respect to the preanoxic value while EMDa did not vary significatively. Compared to control conditions, L-NAME or DETA-NONOate had no influence on the negative chrono-, dromo- and inotropic effects induced by anoxia-reoxygenation. However, L-NAME prolonged EMDv during anoxia and delayed EMDv recovery during reoxygenation while 100 microM DETA-NONOate had the opposite effects. EMDa was neither affected by NOS inhibitor nor NO donor. At the end of reoxygenation, all the investigated parameters returned to their basal values. CONCLUSION: This work provides evidence that a NO-dependent pathway is involved in regulation of the ventricular excitation-contraction coupling in the anoxic-reoxygenated developing heart.

Ranibizumab versus Bevacizumab for Neovascular Age-related Macular Degeneration: Results from the GEFAL Noninferiority Randomized Trial.

OBJECTIVE: To evaluate the relative efficacy and safety profile of bevacizumab versus ranibizumab intravitreal injections for the treatment of neovascular age-related macular degeneration (AMD). DESIGN: Multicenter, prospective, noninferiority, double-masked, randomized clinical trial performed in 38 French ophthalmology centers. The noninferiority limit was 5 letters. PARTICIPANTS: Patients aged ≥50 years were eligible if they presented with subfoveal neovascular AMD, with best-corrected visual acuity (BVCA) in the study eye of between 20/32 and 20/320 measured on the Early Treatment of Diabetic Retinopathy Study chart and a lesion area of less than 12 optic disc areas (DA). METHODS: Patients were randomly assigned to intravitreal administration of bevacizumab (1.25 mg) or ranibizumab (0.50 mg). Hospital pharmacies were responsible for preparing, blinding, and dispensing treatments. Patients were followed for 1 year, with a loading dose of 3 monthly intravitreal injections, followed by an as-needed regimen (1 injection in case of active disease) for the remaining 9 months with monthly follow-up. MAIN OUTCOME MEASURES: Mean change in visual acuity at 1 year. RESULTS: Between June 2009 and November 2011, 501 patients were randomized. In the per protocol analysis, bevacizumab was noninferior to ranibizumab (bevacizumab minus ranibizumab +1.89 letters; 95% confidence interval [CI], -1.16 to +4.93, P < 0.0001). The intention-to-treat analysis was concordant. The mean number of injections was 6.8 in the bevacizumab group and 6.5 in the ranibizumab group (P = 0.39). Both drugs reduced the central subfield macular thickness, with a mean decrease of 95 μm for bevacizumab and 107 μm for ranibizumab (P = 0.27). There were no significant differences in the presence of subretinal or intraretinal fluid at final evaluation, dye leakage on angiogram, or change in choroidal neovascular area. The proportion of patients with serious adverse events was 12.6% in the bevacizumab group and 12.1% in the ranibizumab group (P = 0.88). The proportion of patients with serious systemic or ocular adverse events was similar in both groups. CONCLUSIONS: Bevacizumab was noninferior to ranibizumab for visual acuity at 1 year with similar safety profiles. Ranibizumab tended to have a better anatomic outcome. The results are similar to those of previous head-to-head studies. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

The synthetic Plasmodium falciparum circumsporozoite peptide PfCS102 as a malaria vaccine candidate: a randomized controlled phase I trial.

BACKGROUND: Fully efficient vaccines against malaria pre-erythrocytic stage are still lacking. The objective of this dose/adjuvant-finding study was to evaluate the safety, reactogenicity and immunogenicity of a vaccine candidate based on a peptide spanning the C-terminal region of Plasmodium falciparum circumsporozoite protein (PfCS102) in malaria naive adults. METHODOLOGY AND PRINCIPAL FINDINGS: Thirty-six healthy malaria-naive adults were randomly distributed into three dose blocks (10, 30 and 100 microg) and vaccinated with PfCS102 in combination with either Montanide ISA 720 or GSK proprietary Adjuvant System AS02A at days 0, 60, and 180. Primary end-point (safety and reactogenicity) was based on the frequency of adverse events (AE) and of abnormal biological safety tests; secondary-end point (immunogenicity) on P. falciparum specific cell-mediated immunity and antibody response before and after immunization. The two adjuvant formulations were well tolerated and their safety profile was good. Most AEs were local and, when systemic, involved mainly fatigue and headache. Half the volunteers in AS02A groups experienced severe AEs (mainly erythema). After the third injection, 34 of 35 volunteers developed anti-PfCS102 and anti-sporozoite antibodies, and 28 of 35 demonstrated T-cell proliferative responses and IFN-gamma production. Five of 22 HLA-A2 and HLA-A3 volunteers displayed PfCS102 specific IFN-gamma secreting CD8(+) T cell responses. Responses were only marginally boosted after the 3(rd) vaccination and remained stable for 6 months. For both adjuvants, the dose of 10 microg was less immunogenic in comparison to 30 and 100 microg that induced similar responses. AS02A formulations with 30 microg or 100 microg PfCS102 induced about 10-folds higher antibody and IFN-gamma responses than Montanide formulations. CONCLUSIONS/SIGNIFICANCE: PfCS102 peptide was safe and highly immunogenic, allowing the design of more advanced trials to test its potential for protection. Two or three immunizations with a dose of 30 microg formulated with AS02A appeared the most appropriate choice for such studies. TRIAL REGISTRATION: Swissmedic.ch 2002 DR 1227.

A phase 2 randomized trial of radiotherapy (RT) plus panitumumab compared to chemoradiotherapy in patients with unresected, locally advanced squamous cell carcinoma of the head and neck (SCCHN): interim pooled safety analysis

Background: Panitumumab (pmab), a fully human monoclonal antibody against the epidermal growth factor receptor (EGFR), is indicated as monotherapy for treatment of metastatic colorectal cancer. This ongoing study is designed to assess the efficacy and safety of pmab in combination with radiotherapy (PRT) compared to chemoradiotherapy (CRT) as initial treatment of unresected, locally advanced SCCHN (ClinicalTrials.gov Identifier: NCT00547157). Methods: This is a phase 2, open-label, randomized, multicenter study. Eligible patients (pts) were randomized 2:3 to receive cisplatin 100 mg/m2 on days 1 and 22 of RT or pmab 9.0 mg/kg on days 1, 22, and 43. Accelerated RT (70 to 72 Gy − delivered over 6 to 6.5 weeks) was planned for all pts and was delivered either by intensity-modulated radiation therapy (IMRT) modality or by three-dimensional conformal (3D-CRT) modality. The primary endpoint is local-regional control (LRC) rate at 2 years. Key secondary endpoints include PFS, OS, and safety. An external, independent data monitoring committee conducts planned safety and efficacy reviews during the course of the trial. Results: Pooled data from this planned interim safety analysis includes the first 52 of the 150 planned pts; 44 (84.6%) are male; median (range) age is 57 (33−77) years; ECOG PS 0: 65%, PS 1: 35%; 20 (39%) pts received IMRT, and 32 (61%) pts received 3D-CRT. Fifty (96%) pts completed RT, and 50 pts received RT per protocol without a major deviation. The median (range) total RT dose administered was 72 (64−74) Gy. The most common grade _ 3 adverse events graded using the CTCAE version 3.0 are shown (Table). Conclusions: After the interim safety analysis, CONCERT-2 continues per protocol. Study enrollment is estimated to be completed by October 2009.

A Randomized Controlled Trial Comparing Intradermal vs. Intramuscular Influenza Vaccine in Lung Transplant Recipients

Background: Immunogenicity of standard infl uenza vaccine is suboptimal in lung transplant recipients. Intradermal vaccine may elicit stronger responses due to recruitment of local dendritic cells. We compared the immunogenicity of the infl uenza vaccine administered intradermally (ID) to the standard intramuscular (IM) vaccination. Methods: In this investigator-blinded, two-center, prospective trial, lung transplant patients were randomized to receive intradermal (6ug) or intramuscular (15ug) 2008/9 trivalent inactivated infl uenza vaccine. Immunogenicity was evaluated using a standard hemagglutination inhibition assay (HIA). Response to the vaccine was defi ned as a fourfold increase of the HIA levels for any of the 3 viral strains in the vaccine. Geometric mean titers (GMT) and seroprotection rate (HIA ≥32) were also analyzed. Patients were followed during 6 months for the development of infl uenza or acute rejection. Results: We randomized 84 patients to receive the ID (n=41) vs. IM (n=43) vaccine, respectively. Baseline characteristics were similar between groups. Median time from transplantation was 3.4 yrs (ID) vs. 3.3 yrs (IM) (p=0.84). Vaccine response to at least one antigen was seen in 6/41 (14.6%) patients in the ID vs. 8/43 (18.6%) in the IM group (p=0.77). In the ID group, GMTs (95% CI) after vaccination were 15.7 (11.1-22.3) for H1N1, 84.0 (52.0-135.7) for H3N2, and 14.5 (9.6-21.8) for B strains vs. in the IM group 17.5 (11.8-25.9) for H1N1, 108.9 (77.5-153.2) for H3N2, and 20.2 (12.8-31.9) for B (p=NS, all 3 strains). Seroprotection was 39% (H1N1), 82.9% (H3N2) and 29.3% (B strain) in the ID group vs. 27.9% (H1N1), 97.7% (H3N2) and 58.1% (B strain) in the IM group. No factors associated with vaccine response were identifi ed. Mild adverse events were seen in 44% of patients (ID) vs. 34% (IM) (p=0.38). Two patients (4.8%) in the ID group developed infl uenza infection compared to none in the IM group. Two patients in each group developed biopsy-proven acute rejection during follow-up. Conclusions: Immunogenicity of the 2008/09 infl uenza vaccine was poor in lung transplant recipients. ID administration of the vaccine elicited similar immune responses to standard IM vaccination. Novel strategies of vaccination are needed to protect lung transplant recipients from infl uenza.

Decoding stimulus-related information from single-trial EEG responses based on voltage topographies

Neuroimaging studies typically compare experimental conditions using average brain responses, thereby overlooking the stimulus-related information conveyed by distributed spatio-temporal patterns of single-trial responses. Here, we take advantage of this rich information at a single-trial level to decode stimulus-related signals in two event-related potential (ERP) studies. Our method models the statistical distribution of the voltage topographies with a Gaussian Mixture Model (GMM), which reduces the dataset to a number of representative voltage topographies. The degree of presence of these topographies across trials at specific latencies is then used to classify experimental conditions. We tested the algorithm using a cross-validation procedure in two independent EEG datasets. In the first ERP study, we classified left- versus right-hemifield checkerboard stimuli for upper and lower visual hemifields. In a second ERP study, when functional differences cannot be assumed, we classified initial versus repeated presentations of visual objects. With minimal a priori information, the GMM model provides neurophysiologically interpretable features - vis à vis voltage topographies - as well as dynamic information about brain function. This method can in principle be applied to any ERP dataset testing the functional relevance of specific time periods for stimulus processing, the predictability of subject's behavior and cognitive states, and the discrimination between healthy and clinical populations.

Achievement of VGPR to induction therapy is an important prognostic factor for longer PFS in the IFM 2005-01 trial.

In the 2005-01 trial, we have demonstrated that bortezomib-dexamethasone as induction therapy before autologous stem cell transplantation was superior to vincristine-adriamycin-dexamethasone. We conducted a post-hoc analysis to assess the prognostic impact of initial characteristics as well as response to therapy in patients enrolled in this study. Multivariate analysis showed that ISS stages 2 and 3 and achievement of response less than very good partial response (VGPR) both after induction therapy and after autologous stem cell transplantation were adverse prognostic factors for progression-free survival, the most important one being achievement of response less than VGPR after induction. Progression-free survival was significantly improved with bortezomib-dexamethasone induction therapy in patients with poor-risk cytogenetics and ISS stages 2 and 3 compared with vincristine-adriamycin-dexamethasone. In these 2 groups of patients, achievement of at least VGPR after induction was of major importance. This study is registered with EudraCT (https://eudract.ema.europa.eu; EUDRACT 2005-000537-38) and http://clinicaltrials.gov (NCT00200681).

Integrated Analysis of High-Resolution Gene Expression and Copy Number Profiling Identified Biallelic Deletion of CDKN2A/2B Tumor Suppressor Locus As the Most Frequent and Unique Genomic Abnormality in Diffuse Large B-Cell Lymphoma (DLBCL) with Strong Prognostic Value in Both GCB and ABC Subtypes and Not Overcome by a Dose-Intensive Immunochemotherapy Regimen Plus Rituximab. Results of a Prospective GELA Clinical Trial Program

Background and aim of the study: Genomic gains and losses play a crucial role in the development and progression of DLBCL and are closely related to gene expression profiles (GEP), including the germinal center B-cell like (GCB) and activated B-cell like (ABC) cell of origin (COO) molecular signatures. To identify new oncogenes or tumor suppressor genes (TSG) involved in DLBCL pathogenesis and to determine their prognostic values, an integrated analysis of high-resolution gene expression and copy number profiling was performed. Patients and methods: Two hundred and eight adult patients with de novo CD20+ DLBCL enrolled in the prospective multicentric randomized LNH-03 GELA trials (LNH03-1B, -2B, -3B, 39B, -5B, -6B, -7B) with available frozen tumour samples, centralized reviewing and adequate DNA/RNA quality were selected. 116 patients were treated by Rituximab(R)-CHOP/R-miniCHOP and 92 patients were treated by the high dose (R)-ACVBP regimen dedicated to patients younger than 60 years (y) in frontline. Tumour samples were simultaneously analysed by high resolution comparative genomic hybridization (CGH, Agilent, 144K) and gene expression arrays (Affymetrix, U133+2). Minimal common regions (MCR), as defined by segments that affect the same chromosomal region in different cases, were delineated. Gene expression and MCR data sets were merged using Gene expression and dosage integrator algorithm (GEDI, Lenz et al. PNAS 2008) to identify new potential driver genes. Results: A total of 1363 recurrent (defined by a penetrance > 5%) MCRs within the DLBCL data set, ranging in size from 386 bp, affecting a single gene, to more than 24 Mb were identified by CGH. Of these MCRs, 756 (55%) showed a significant association with gene expression: 396 (59%) gains, 354 (52%) single-copy deletions, and 6 (67%) homozygous deletions. By this integrated approach, in addition to previously reported genes (CDKN2A/2B, PTEN, DLEU2, TNFAIP3, B2M, CD58, TNFRSF14, FOXP1, REL...), several genes targeted by gene copy abnormalities with a dosage effect and potential physiopathological impact were identified, including genes with TSG activity involved in cell cycle (HACE1, CDKN2C) immune response (CD68, CD177, CD70, TNFSF9, IRAK2), DNA integrity (XRCC2, BRCA1, NCOR1, NF1, FHIT) or oncogenic functions (CD79b, PTPRT, MALT1, AUTS2, MCL1, PTTG1...) with distinct distribution according to COO signature. The CDKN2A/2B tumor suppressor locus (9p21) was deleted homozygously in 27% of cases and hemizygously in 9% of cases. Biallelic loss was observed in 49% of ABC DLBCL and in 10% of GCB DLBCL. This deletion was strongly correlated to age and associated to a limited number of additional genetic abnormalities including trisomy 3, 18 and short gains/losses of Chr. 1, 2, 19 regions (FDR < 0.01), allowing to identify genes that may have synergistic effects with CDKN2A/2B inactivation. With a median follow-up of 42.9 months, only CDKN2A/2B biallelic deletion strongly correlates (FDR p.value < 0.01) to a poor outcome in the entire cohort (4y PFS = 44% [32-61] respectively vs. 74% [66-82] for patients in germline configuration; 4y OS = 53% [39-72] vs 83% [76-90]). In a Cox proportional hazard prediction of the PFS, CDKN2A/2B deletion remains predictive (HR = 1.9 [1.1-3.2], p = 0.02) when combined with IPI (HR = 2.4 [1.4-4.1], p = 0.001) and GCB status (HR = 1.3 [0.8-2.3], p = 0.31). This difference remains predictive in the subgroup of patients treated by R-CHOP (4y PFS = 43% [29-63] vs. 66% [55-78], p=0.02), in patients treated by R-ACVBP (4y PFS = 49% [28-84] vs. 83% [74-92], p=0.003), and in GCB (4y PFS = 50% [27-93] vs. 81% [73-90], p=0.02), or ABC/unclassified (5y PFS = 42% [28-61] vs. 67% [55-82] p = 0.009) molecular subtypes (Figure 1). Conclusion: We report for the first time an integrated genetic analysis of a large cohort of DLBCL patients included in a prospective multicentric clinical trial program allowing identifying new potential driver genes with pathogenic impact. However CDKN2A/2B deletion constitutes the strongest and unique prognostic factor of chemoresistance to R-CHOP, regardless the COO signature, which is not overcome by a more intensified immunochemotherapy. Patients displaying this frequent genomic abnormality warrant new and dedicated therapeutic approaches.

Single-trial topographic analysis of human EEG: A new image of event-related potentials

We present a novel approach for analyzing single-trial electroencephalography (EEG) data, using topographic information. The method allows for visualizing event-related potentials using all the electrodes of recordings overcoming the problem of previous approaches that required electrode selection and waveforms filtering. We apply this method to EEG data from an auditory object recognition experiment that we have previously analyzed at an ERP level. Temporally structured periods were statistically identified wherein a given topography predominated without any prior information about the temporal behavior. In addition to providing novel methods for EEG analysis, the data indicate that ERPs are reliably observable at a single-trial level when examined topographically.

Robotic Gait Training Is not Superior to Conventional Treadmill Training in Parkinson Disease: A Single-Blind Randomized Controlled Trial.

BACKGROUND: The use of robots for gait training in Parkinson disease (PD) is growing, but no evidence points to an advantage over the standard treadmill. METHODS: In this randomized, single-blind controlled trial, participants aged <75 years with early-stage PD (Hoehn-Yahr <3) were randomly allocated to 2 groups: either 30 minutes of gait training on a treadmill or in the Lokomat for 3 d/wk for 4 weeks. Patients were evaluated by a physical therapist blinded to allocation before and at the end of treatment and then at the 3- and 6-month follow-up. The primary outcome measure was the 6-minute walk test. RESULTS: Of 334 screened patients, the authors randomly allocated 30 to receive gait training with treadmill or the Lokomat. At baseline, the 2 groups did not differ. At the 6-month follow-up, both groups had improved significantly in the primary outcome measure (treadmill: mean = 490.95 m, 95% confidence interval [CI] = 448.56-533.34, P = .0006; Lokomat: 458.6 m, 95% CI = 417.23-499.96, P = .01), but no significant differences were found between the 2 groups (P = .53). DISCUSSION: Robotic gait training with the Lokomat is not superior to treadmill training in improving gait performance in patients with PD. Both approaches are safe, with results maintained for up to 6 months.

Change in defense mechanisms and coping patterns during the course of 2-year-long psychotherapy and psychoanalysis for recurrent depression: a pilot study of a randomized controlled trial.

Very little research has been conducted so far to study the potential mechanisms of change in long-term active psychological treatments of recurrent depression. The present pilot randomized controlled trial aimed to determine the feasibility of studying the change process occurring in patients during the course of 2-year-long dynamic psychotherapy, psychoanalysis, and cognitive therapy, as compared with clinical management. In total, eight outpatients presenting with recurrent depression, two patients per treatment arm, were included. All patients were randomly assigned to one of the four treatment conditions. Defense mechanisms and coping patterns were assessed using validated observer-rated methodology based on transcribed, semistructured follow-along independent dynamic interviews. The results indicated that, whereas some patients in the active treatments changed on the symptomatic levels, some others remained unchanged during the course of their 2-year-long treatment. However, with regard to potential mechanisms of change in these patients, changes in defense mechanisms and coping patterns were revealed to be important processes over time in successful therapies and, to a lesser extent, in less successful treatments. No change was found either on outcome or on the process measure for the control condition, that is, clinical management. These results are discussed along with previous data comparing change in defense mechanisms and coping during the course of treatments.

Three-dimensional ordered-subset expectation maximization iterative protocol for evaluation of left ventricular volumes and function by quantitative gated SPECT: a dynamic phantom study.

The purposes of this study were to characterize the performance of a 3-dimensional (3D) ordered-subset expectation maximization (OSEM) algorithm in the quantification of left ventricular (LV) function with (99m)Tc-labeled agent gated SPECT (G-SPECT), the QGS program, and a beating-heart phantom and to optimize the reconstruction parameters for clinical applications. METHODS: A G-SPECT image of a dynamic heart phantom simulating the beating left ventricle was acquired. The exact volumes of the phantom were known and were as follows: end-diastolic volume (EDV) of 112 mL, end-systolic volume (ESV) of 37 mL, and stroke volume (SV) of 75 mL; these volumes produced an LV ejection fraction (LVEF) of 67%. Tomographic reconstructions were obtained after 10-20 iterations (I) with 4, 8, and 16 subsets (S) at full width at half maximum (FWHM) gaussian postprocessing filter cutoff values of 8-15 mm. The QGS program was used for quantitative measurements. RESULTS: Measured values ranged from 72 to 92 mL for EDV, from 18 to 32 mL for ESV, and from 54 to 63 mL for SV, and the calculated LVEF ranged from 65% to 76%. Overall, the combination of 10 I, 8 S, and a cutoff filter value of 10 mm produced the most accurate results. The plot of the measures with respect to the expectation maximization-equivalent iterations (I x S product) revealed a bell-shaped curve for the LV volumes and a reverse distribution for the LVEF, with the best results in the intermediate range. In particular, FWHM cutoff values exceeding 10 mm affected the estimation of the LV volumes. CONCLUSION: The QGS program is able to correctly calculate the LVEF when used in association with an optimized 3D OSEM algorithm (8 S, 10 I, and FWHM of 10 mm) but underestimates the LV volumes. However, various combinations of technical parameters, including a limited range of I and S (80-160 expectation maximization-equivalent iterations) and low cutoff values (< or =10 mm) for the gaussian postprocessing filter, produced results with similar accuracies and without clinically relevant differences in the LV volumes and the estimated LVEF.