Single Photon Emission Computed Tomography Results Research Articles

Comparative Effectiveness of PET and SPECT MPI for Predicting Cardiovascular Events After Kidney Transplant.

Advanced chronic kidney disease is associated with high cardiovascular risk, even after kidney transplant. Pretransplant cardiac testing may identify patients who require additional assessment before transplant or would benefit from risk optimization. The objective of the current study was to determine the relative prognostic utility of pretransplant positron emission tomography (PET) and single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) for posttransplant major adverse cardiovascular events (MACEs). We retrospectively followed patients who underwent MPI before kidney transplant for the occurrence of MACE after transplant including myocardial infarction, stroke, heart failure, and cardiac death. An abnormal MPI result was defined as a total perfusion deficit >5% of the myocardium. To determine associations of MPI results with MACE, we utilized Cox hazard regression with propensity weighting for PET versus SPECT with model factors, including demographics and cardiovascular risk factors. A total of 393 patients underwent MPI (208 PET and 185 SPECT) and were followed for a median of 5.9 years post-transplant. Most were male (58%), median age was 58 years, and there was a high burden of hypertension (88%) and diabetes (33%). A minority had abnormal MPI (n=58, 15%). In propensity-weighted hazard regression, abnormal PET result was associated with posttransplant MACE (hazard ratio, 3.02 [95% CI, 1.78-5.11]; P<0.001), while there was insufficient evidence of an association of abnormal SPECT result with MACE (1.39 [95% CI, 0.72-2.66]; P=0.33). The explained relative risk of the PET result was higher than the SPECT result (R2 0.086 versus 0.007). Normal PET was associated with the lowest risk of MACE (2.2%/year versus 3.6%/year for normal SPECT; P<0.001). Kidney transplant recipients are at high cardiovascular risk, despite a minority having obstructive coronary artery disease on MPI. PET MPI findings predict posttransplant MACE. Normal PET may better discriminate lower risk patients compared with normal SPECT, which should be confirmed in a larger prospective study.

Microstructural alterations in white matter and related neurobiology based on the new clinical subtypes of Parkinson's disease.

The advent of new clinical subtyping systems for Parkinson's disease (PD) has led to the classification of patients into distinct groups: mild motor predominant (PD-MMP), intermediate (PD-IM), and diffuse malignant (PD-DM). Our goal was to evaluate the efficacy of diffusion tensor imaging (DTI) in the early diagnosis, assessment of clinical progression, and prediction of prognosis of these PD subtypes. Additionally, we attempted to understand the pathological mechanisms behind white matter damage using single-photon emission computed tomography (SPECT) and cerebrospinal fluid (CSF) analyses. We classified 135 de novo PD patients based on new clinical criteria and followed them up after 1 year, along with 45 healthy controls (HCs). We utilized tract-based spatial statistics to assess the microstructural changes of white matter at baseline and employed multiple linear regression to examine the associations between DTI metrics and clinical data at baseline and after follow-up. Compared to HCs, patients with the PD-DM subtype demonstrated reduced fractional anisotropy (FA), increased axial diffusivity (AD), and elevated radial diffusivity (RD) at baseline. The FA and RD values correlated with the severity of motor symptoms, with RD also linked to cognitive performance. Changes in FA over time were found to be in sync with changes in motor scores and global composite outcome measures. Furthermore, baseline AD values and their rate of change were related to alterations in semantic verbal fluency. We also discovered the relationship between FA values and the levels of α-synuclein and β-amyloid. Reduced dopamine transporter uptake in the left putamen correlated with RD values in superficial white matter, motor symptoms, and autonomic dysfunction at baseline as well as cognitive impairments after 1 year. The PD-DM subtype is characterized by severe clinical symptoms and a faster progression when compared to the other subtypes. DTI, a well-established technique, facilitates the early identification of white matter damage, elucidates the pathophysiological mechanisms of disease progression, and predicts cognitively related outcomes. The results of SPECT and CSF analyses can be used to explain the specific pattern of white matter damage in patients with the PD-DM subtype.

Myocardial Flow Assessment After Heart Transplantation Using Dynamic Cadmium-Zinc-Telluride Single-Photon Emission Computed Tomography With 201Tl and 99mTc Tracers and Validated by 13N-NH3 Positron Emission Tomography.

Cardiac allograft vasculopathy (CAV) is an obliterative and diffuse form of vasculopathy and is the most common cause of long-term cardiovascular mortality in heart transplant patients. This study aimed to investigate the diagnostic performance of 99mTc and 201Tl tracers in the assessment of CAV using cadmium-zinc-telluride (CZT) single-photon emission computed tomography (SPECT) for myocardial blood flow (MBF) and myocardial flow reserve (MFR) quantification, which was further validated using 13 N-NH3 positron emission tomography (PET). Thirty-eight patients with prior heart transplantation who underwent CZT SPECT and 13 N-NH3 PET dynamic scans were included in this study. CZT SPECT with 99mTc-sestamibi was used in the first 19 patients and 201Tl-chloride for the remaining patients. To determine the diagnostic accuracy of angiographically defined moderate-to-severe CAV, the analysis included patients who underwent angiographic examinations within 1 year of their second scan. There were no significant differences in the patient characteristics between the 201Tl and 99mTc tracer groups. Both 201Tl and 99mTc CZT SPECT-derived stress MBF and MFR values globally and in 3 coronary territories showed good correlations with 13 N-NH3 PET. The 201Tl and 99mTc cohorts did not differ significantly in the correlation coefficients of CZT SPECT versus PET for MBF and MFR, except for stress MBF (201Tl:0.95 versus 99mTc:0.80, P=0.03). 201Tl and 99mTc CZT SPECT were satisfactory for detecting PET MFR <2.0 (201Tl area under the curve, 0.92 [0.71-0.99], 99mTc area under the curve, 0.87 [0.64-0.97]) and angiographically defined moderate-to-severe CAV, and CZT SPECT results were comparable to that of 13 N-NH3 PET (CZT area under the curve, 0.90 [0.70-0.99], PET area under the curve, 0.86 [0.64-0.97]). This small study suggests that CZT SPECT using 201Tl and 99mTc tracers showed comparable MBF and MFR, and the results correlated well with those of 13 N-NH3 PET. Hence, CZT SPECT with 201Tl or 99mTc tracers can be used to detect moderate-to-severe CAV in patients with prior heart transplantation. However, validation using larger studies is warranted.

The impact of cardiac SPECT in risk stratification for women with suspected coronary artery disease in a very high cardiovascular risk country

Abstract Funding Acknowledgements Type of funding sources: None. Background Risk stratification has become increasingly important in the management of women with coronary artery disease (CAD). Population based cross-sectional study of cardiovascular risk (CVR) factors in Latvia revealed that women in age 25 -74 are in a very high CVR group: more than 60% of women have dyslipidemia, 30% have arterial hypertension (AH) and are overweight. Purpose To evaluate CVR factor profile in women with suspected CAD and performed cardiac single photon emission computed tomography (SPECT) and to prove the need of perfusion imaging for women in a very high cardiovascular risk population. Methods Cardiac SPECT for women with suspected CAD and positive or non-informative exercise test was performed in a single center from 2018 till 2022. The patients were analyzed by risk factors and perfusion test result, divided into 2 groups: normal myocardial perfusion or true myocardial perfusion defect. Results 466 patients without known CAD were analyzed. The mean age of cohort patients was 59.3±10.9 years. 28 (6.0%) patients had no CVR factors, 90 (19.3%) women had only 1, but the rest of them (348, 74.7%) had 2 or more CVR factors. Dyslipidemia was present in 358 (76.8%), AH in 282 (60.5%) and type 2 Diabetes mellitus (T2DM) in 27 (5.8%) patients. More than half of patients (n=303, 65.0%) were overweight (BMI&amp;gt;25.0 kg/m2). 65 (13.9%) women were current or ex-smokers. True myocardial perfusion defect was detected in 96 patients (20.6%). There was no statistically significant difference between CVR risk factor count and cardiac SPECT result (p=0.229), although there were patients with significant perfusion defect without any risk factor present. However, significant correlation between risk factors and detection of obstructive coronary artery disease (CAD) after positive cardiac SPECT was found (p&amp;lt;0.001). Totally in study was detected 71 patients with suspected ischemia with non-obstructive CAD (INOCA), but further investigation with intracoronary physiology measurements – coronary flow reserve (CFR), index of microvascular resistance (IMR) and acetylcholine provocation test is required to define INOCA endotype. Conclusions The cardiac SPECT is an appropriate diagnostic method for women patients with suspected CAD. Even in patients with no CVR factors, but with positive or non-informative exercise test, the CAD is present, therefore they should be referred to cardiac SPECT in a very high CVR country. In patients with significant perfusion defect and absence of obstructive CAD, the performance of intracoronary physiology measurements is required.

Localization of epileptic focus in children with intractable epilepsy

Background Epilepsy is a common neurological disorder. Preoperative evaluation of intractable epileptic patients requires identification of the brain area that is responsible for generating seizure activity. The developments of functional brain imaging with positron emission tomography, single-photon emission computed tomography (SPECT), and functional magnetic resonance imaging (MRI) have ensured its clinical relevance. Aim The aim of this work was to evaluate the role of Tc-99m hexamethylpropylene amine oxime brain-perfusion SPECT and comparing it with MRI) and electroencephalogram (EEG) in the localization of epileptic focus in children with medically intractable epilepsy. Patients and Methods The study population consisted of twenty children with medically intractable epilepsy. They were subjected to complete history taking, clinical assessment, laboratory assessment, and radiological assessment, including EEG, traditional MRI, and SPECT. Results Medically intractable epilepsy is more likely to occur in children with early age of onset, high frequency of seizures per month, more reliability of febrile seizures, and having associated neurological abnormalities. It is more likely to occur in focal forms of seizures than in generalized forms. Children with focal EEG activity and focal seizures are the most likely group to have abnormal brain MRI results and abnormal cerebral perfusion in SPECT. MRI is very important in the localization of structural lesions, but SPECT in localization of functional lesions. Conclusion Interictal SPECT results were nearly the same as the MRI results.

Using 3D Medical Modeling to Evaluate the Accuracy of Single-Photon Emission Computed Tomography (SPECT) Bone Scintigraphy in Diagnosing Condylar Hyperplasia

To evaluate the accuracy of single-photon emission computed tomography (SPECT) in diagnosing unilateral condylar hyperplasia (UCH) and to describe the condylar growth of patients with UCH. Using a retrospective study design, patients with UCH who had undergone SPECT and cone-beam computed tomography (CBCT) examinations at the same time were included in the study. We used 3D medical models based on CBCT data as the gold standard. The SPECT results were compared with the model data, and the sensitivity and specificity were calculated. To further describe the condylar growth activity, statistical analysis was performed, and the P value was set at 0.05. The sample was composed of 75 patients. The sensitivity of SPECT was 55.3%, the specificity was 48.6%, and the area under the receiver operating characteristic curve was 0.53. There was no significant difference in sex between patients with and without active growth. The sensitivity and specificity of SPECT are poor, and SPECT alone is not suitable for evaluating the active stage of condylar growth. 3D medical modeling has good prospects for application in the diagnosis of condylar hyperplasia.

Three-dimensional quantitative assessment of myocardial infarction via multimodality fusion imaging: methodology, validation, and preliminary clinical application.

The precise assessment of myocardial infarction (MI) is crucial both for therapeutic interventions in old MI and the development of new and effective techniques to repair injured myocardium. A novel method was developed to assess left ventricular (LV) quantitatively infarction through three-dimensional (3D) multimodality fusion based on computed tomography angiography (CTA) and technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) single-photon emission computed tomography (SPECT) images. This study sought to develop a 3D quantitative method for MI for pre-clinical study and clinical application. Three months after the MI models were established in 20 minipigs, CTA and SPECT images were acquired separately, which were then aligned automatically with the constraints of the shape and the whole heart and LV myocardium position. Infarct ratios were quantified based on the 3D fusion images. The quantitative assessment was then experimentally validated via an ex vivo histology analysis using triphenyl-tetrazolium-chloride staining and subsequently applied to post-MI patients (n=8). The location of an infarct identified by the SPECT was consistent with that identified by an ex vivo heart in a 3D space. Infarct size determined by CTA-SPECT was correlated with infarct size assessed by triphenyl-tetrazolium-chloride pathology {27.6% [interquartile range (IQR) 17.1-34.7%] vs. 24.1% (IQR 14.7-32.5%), r2=0.99, P<0.01}. In clinical cases, the CTA-SPECT 3D fusion quantitative results were significantly correlated with the quantitative perfusion SPECT results (r=0.976, P<0.01). The proposed 3D fusion quantitative assessment method provides reliable and intuitive evaluations of infarction. This novel quantification technique enables whole heart quantification for the pre-operation evaluation and post-diagnosis management of old MI patients. It could also be applied to the design of 3D-printed cardiac patches.

Diagnosing Transthyretin Cardiac Amyloidosis by Technetium Tc 99m Pyrophosphate: A Test in Evolution

ObjectivesThis study aimed to characterize trends in technetium Tc 99m pyrophosphate (99mTc-PYP) scanning for amyloid transthyretin cardiac amyloidosis (ATTR-CA) diagnosis, to determine whether patients underwent appropriate assessment with monoclonal protein and genetic testing, to evaluate use of single-photon emission computed tomography (SPECT) in addition to planar imaging, and to identify predictive factors for ATTR-CA. Background99mTc-PYP scintigraphy has been repurposed for noninvasive diagnosis of ATTR-CA. Increasing use of 99mTc-PYP can facilitate identification of ATTR-CA, but appropriate use is critical for accurate diagnosis in an era of high-cost targeted therapeutics. MethodsPatients undergoing 99mTc-PYP scanning 1 h after injection at a quaternary care center from 2010 to 2019 were analyzed; clinical information was abstracted; and SPECT results were analyzed. ResultsOver the decade, endomyocardial biopsy rates remained stable with scanning rates peaking at 132 in 2019 (p < 0.001). Among 753 patients (516 men, mean age 77 years), 307 (41%) had a visual score of 0, 177 (23%) of 1, and 269 (36%) of 2 or 3. Of 751 patients with analyzable heart to contralateral chest ratios, 249 (33%) had a ratio ≥1.5. Monoclonal protein testing status was assessed in 550 patients, of these, 174 (32%) did not undergo both serum immunofixation and serum free light chain analysis tests, and 331 (60%) did not undergo all 3 tests—serum immunofixation, serum free light chain analysis, and urine protein electrophoresis. Of 196 patients with confirmed ATTR-CA, 143 (73%) had genetic testing for transthyretin mutations. In 103 patients undergoing cardiac biopsy, grades 2 and 3 99mTc-PYP had sensitivity of 94% and specificity of 89% for ATTR-CA with 100% specificity for grade 3 scans. With respect to SPECT as a reference standard, planar imaging had false positive results in 16 of 25 (64%) grade 2 scans. ConclusionsUse of noninvasive testing with 99mTc-PYP scanning for evaluation of ATTR-CA is increasing, and the inclusion of monoclonal protein testing and SPECT imaging is crucial to rule out amyloid light chain amyloidosis and distinguish myocardial retention from blood pooling.

Efficient 1-Hour Technetium-99 m Pyrophosphate Imaging Protocol for the Diagnosis of Transthyretin Cardiac Amyloidosis.

Technetium-99 m pyrophosphate protocols for transthyretin cardiac amyloidosis diagnosis have variably used 1- and 3-hour imaging time points. We investigated whether imaging at 1 hour with superior efficiency had comparable diagnostic accuracy as 3-hour imaging. This is a registry analysis of patients with suspected transthyretin cardiac amyloidosis referred for technetium-99 m pyrophosphate at a single tertiary center from June 2015 through January 2019. Patients underwent planar and single-photon emission computed tomography (SPECT) imaging at 1 and 3 hours. A positive Tc-99m pyrophosphate study was defined by the presence of diffuse myocardial tracer uptake on SPECT. For planar imaging, visual semiquantitative (grades 0-3, ≥2 considered positive) and quantitative heart to contralateral ratios (≥1.5 considered positive) were used. Two hundred thirty-three patients (69% men; median age, 77 [69-83] years) underwent the study protocol. There were 60 (25.8%) patients with diffuse myocardial uptake, 1 (0.4%) with regional uptake, and 172 (73.8%) with no myocardial uptake. Results of SPECT were identical at 1 and 3 hours. Planar imaging at 1 hour had 98% sensitivity and 96% specificity. Planar grade 0 uptake or heart to contralateral ratio ≤1.2 and planar grade 3 uptake or heart to contralateral ratio ≥2.0 were always associated with negative and positive SPECT, respectively. For planar grades 1 and 2 uptake and heart to contralateral ratio 1.3 to 1.9, SPECT was needed to make a diagnosis. No patient with light-chain cardiac amyloidosis had positive SPECT. An efficient 1-hour technetium-99 m pyrophosphate protocol had comparable diagnostic performance to a 3-hour protocol.

Correlation between electromechanical parameters (NOGA XP) and changes of myocardial ischemia in patients with refractory angina.

IntroductionCell therapy has the potential to improve symptoms and clinical outcomes in refractory angina (RFA). Further analyses are needed to evaluate factors influencing its therapeutic effectiveness.AimAssessment of electromechanical (EM) parameters of the left ventricle (LV) and investigation of correlation between EM parameters of the myocardium and response to CD133+ cell therapy.Material and methodsThirty patients with RFA (16 active and 14 placebo individuals) enrolled in the REGENT-VSEL trial underwent EM evaluation of the LV with intracardiac mapping system. The following parameters were analyzed: unipolar voltage (UV), bipolar voltage (BV), local linear shortening (LLS). Myocardial ischemia was evaluated with single-photon emission computed tomography (SPECT). The median value of each EM parameter was used for intra-group comparisons.ResultsGlobal EM parameters (UV, BV, LLS) of LV in active and placebo groups were 11.28 mV, 3.58 mV, 11.12%, respectively; 13.00 mV, 3.81 mV, 11.32%, respectively. EM characteristics analyzed at global and segmental levels did not predict response to CD133+ cell therapy in patients with RFA (Global UV, BV and LLS at rest R = –0.06; R = 0.2; R = –0.1 and at stress: R = 0.07, R = 0.09, R = –0.1, respectively; Segmental UV, BV, LLS at rest R = –0.2, R = 0.03, R = –0.4 and at stress R = 0.02, R = 0.2, R = –0.2, respectively). Multiple linear regression of the treated segments showed that only pre-injection SPECT levels were significantly correlated with post-injection SPECT, either at rest or stress (p < 0.05).ConclusionsElectromechanical characteristics of the left ventricle do not predict changes of myocardial perfusion by SPECT after cell therapy. Baseline SPECT results are only predictors of changes of myocardial ischemia observed at 4-month follow-up.

Does SPECT Provide Incremental Value to CT or MRI in Assessing Mandibular Invasion by Oral Squamous Cell Carcinoma?

Single photon emission computed tomography (SPECT) has been commonly used as an additional method to assess mandibular bone invasion in patients with oral squamous cell carcinoma (OSCC). In the present study, we measured the diagnostic validity of SPECT findings compared with the histologic findings. We implemented a retrospective cross-sectional study and enrolled a sample of patients with OSCC adjacent to the mandible. The staging examinations included magnetic resonance imaging (MRI) and/or computed tomography (CT) and additional SPECT. The patients' medical records and imaging data were reviewed by 2 readers, and bone invasion was classified as positive or negative for each diagnostic method. The predictor was bone invasion found on CT and/or MRI compared with the combination of CT and/or MRI with either positive or negative SPECT results. The primary outcome variable was histologic bone invasion. Other variables of interest were clinicopathologic data, type of mandibular resection, and resection margin status. Bivariate tests were used to compare the diagnostic specificity, sensitivity, and accuracy of each imaging modality. The study enrolled 122 patients, with a mean age of 67years (55% male; study period, January 2010 to December 2017). In 60 patients (49%), segmental mandibular resection was performed. The sensitivity and specificity for bone invasion were 100% and 39% for SPECT and 84% and 75% for CT and/or MRI. The negative results for bone invasion using SPECT did not match the false-positive CT and/or MRI results in 5% (n=6 of 122). Positive SPECT findings, in addition to positive CT and/or MRI findings increased the sensitivity to 100% but decreased the specificity to 29% (P<.001). Considering only negative SPECT findings increased the specificity to 85% (P=.03), sensitivity remaining unaffected. The accuracy of CT and/or MRI alone was 80% and was 84% when combining CT and/or MRI and negative SPECT findings (P=.03). In oncologic staging with CT and/or MRI, the addition of SPECT provided only small benefits. Only negative SPECT results allowed for greater specificity and accuracy. The use of SPECT could be considered to rule out bone invasion in cases of radiologic uncertainty of positive CT or MRI findings.

SPECT imaging of lung ischemia-reperfusion injury using [99mTc]cFLFLF for molecular targeting of formyl peptide receptor 1.

Primary graft dysfunction after lung transplantation, a consequence of ischemia-reperfusion injury (IRI), is a major cause of morbidity and mortality. IRI involves acute inflammation and innate immune cell activation, leading to rapid infiltration of neutrophils. Formyl peptide receptor 1 (FPR1) expressed by phagocytic leukocytes plays an important role in neutrophil function. The cell surface expression of FPR1 is rapidly and robustly upregulated on neutrophils in response to inflammatory stimuli. Thus, we hypothesized that use of [99mTc]cFLFLF, a selective FPR1 peptide ligand, would permit in vivo neutrophil labeling and noninvasive imaging of IRI using single-photon emission computed tomography (SPECT). A murine model of left lung IRI was utilized. Lung function, neutrophil infiltration, and SPECT imaging were assessed after 1 h of ischemia and 2, 12, or 24 h of reperfusion. [99mTc]cFLFLF was injected 2 h before SPECT. Signal intensity by SPECT and total probe uptake by gamma counts were 3.9- and 2.3-fold higher, respectively, in left lungs after ischemia and 2 h of reperfusion versus sham. These values significantly decreased with longer reperfusion times, correlating with resolution of IRI as shown by improved lung function and decreased neutrophil infiltration. SPECT results were confirmed using Cy7-cFLFLF-based fluorescence imaging of lungs. Immunofluorescence microscopy confirmed cFLFLF binding primarily to activated neutrophils. These results demonstrate that [99mTc]cFLFLF SPECT enables noninvasive detection of lung IRI and permits monitoring of resolution of injury over time. Clinical application of [99mTc]cFLFLF SPECT may permit diagnosis of lung IRI for timely intervention to improve outcomes after transplantation.

1273Efficacy and safety of prehabilitation before coronary artery bypass grafting

Abstract Purpose To evaluate the effectiveness and safety of high intensity prehabilitation included in the routine preoperative management of patients with coronary artery disease (CAD) for elective on-pump coronary artery bypass grafting (CABG). Methods 38 male patients with stable CAD referred to on-pump CABG who either underwent prehabilitation or not were assigned into two study groups. Group 1 patients (n=20, the mean age 61.5 years [55; 64] underwent high intensity treadmill exercises. Group 2 patients (n=18, the mean age 62.0 years [56; 65]) underwent routine preoperative management without prehabilitation. Treadmill exercises in Group 1 patients were performed under hemodynamic control and ECG monitoring. The training power of a workout was calculated based on cardiopulmonary exercise test (CPET) performed before preoperative exercises, and was estimated as 80% of the maximal power obtained during the exercise test. Adenosine loading single-photon emission computed tomography (SPECT) was used to measure the parameters of myocardial perfusion before preoperative exercises and on days 5–7 after CABG in both study groups. Biochemical markers of myocardial damage (troponin I, NT-proBNP) were measured before the training session, after it and then in the postoperative period to assess the safety of the prehabilitation program. In-hospital postoperative complications were recorded and analyzed. Results Both study groups were comparable in the main clinical and demographic parameters, intraoperative clinical parameters as well as in preoperative CPET and SPECT results. There were no cases of complications during prehabilitation. The analysis of myocardial perfusion parameters demonstrated that patients who had undergone prehabilitation had significantly higher accumulation of radiopharmaceuticals than those in the control group in basal segments (74.9±3.98% vs. 70.3±7.40% p=0.04), middle (86.7±5.24% vs. 79.6±10.43%, p=0.03) and apical (85.8±5.03% vs. 79.0±8,67%, p=0.02) myocardium. The stress-induced ischemia (SDS) was less pronounced in Group 1 compared to Group 2 (0 scores and 0.9±0.53 scores, respectively, p=0.04). Myocardial perfusion defect significantly decreased during the infusion of adenosine (SSS) (p=0.013), as well as the SDS index (p=0.018) in the prehabilitation group after CABG compared with the baseline. Both groups had similar serum troponin I levels within the normal range before and after CABG. NT-pro BNP levels significantly increased in the postoperative period in patients who did not undergo prehabilitation (p=0.003). Patients who underwent prehabilitation had a significantly lower incidence of the in-hospital postoperative complications compared to patients without exercise trainings (p=0.002). Conclusion The inclusion of high intensity preoperative exercises in the routine preoperative management of patients referred to elective CABG is safe and effective method of cardioprotection improving surgical outcomes.

Use of &lt;sup&gt;99m&lt;/sup&gt;Tc-MIBI spect in estimating the efficiency pre-operative treatment of the larynx and laryngopharynx cancer

Purpose of the study. To study the possibilities of 99mTc-MIBI single photon emission computed tomography (SPECT) at the monitoring of the preoperative treatment of patients with laryngeal and hypopharyngeal cancer. Materials and methods. The study included 28 pa tients with cancer of the larynx or laryngopharynx T2–3N0–2M0. 99mTc-MIBI SPECT was performed for all patients before and after preoperative treatment, semi-quantitative indices were calculated, according to SPECT Results. A statistically significant difference was observed in the retention index in patients with complete regression and stabilization. A lower retention index is observed in patients who had a clinically pronounced effect from preoperative treatment. The rate of radiotracer washout from the tumor was faster in patients with no effect of preoperative therapy. The level of radiopharmaceuticals uptake in the tumor tissue after preoperative treatment was significantly lower in the group of patients without progression than in the group of patients with progression of the disease. In addition, the accumulation of the radioindicator after preoperative chemotherapy increased in the group of patients with progression, and decreased in the group without progression.Conclusion. The 99mTc-MIBI SPECT for tumor monitoring during treatment can be used. Semi-quantitative indices can be used as predictive criteria of results of preoperative treatment, as well as prognostic criteria for monitoring of such patients.

Value of early rest myocardial perfusion imaging with SPECT in patients with chest pain and non-diagnostic ECG in emergency department.

Evaluation of atypical presentation of angina chest pain in emergency department is difficult. Hospitalization of this patient may impose additional costs and waste the time, early discharge may lead to miss the patients. The aim of this study was to determine volubility of Single Photon Emission Computed Tomography (SPECT) in management of patients admitted to emergency department with atypical manifestations of angina pain, un-diagnostic Electrocardiogram (ECG) and negative enzyme. Half of 100 patients admitted to emergency department with atypical chest pain and un-diagnostic ECG who were candidate for admission, underwent ECG gated resting SPECT. According to the results of SPECT, low risk patient discharged after negative stress SPECT. All discharged patients were followed up for major cardiac events (cardiac death, nonfatal myocardial infarction and repeat admission for congestive heart failure) for 12months. According to rest SPECT Myocardial Perfusion Imaging (MPI), about 70% of patients in case group was low risk and 30% of them had moderate or high risk. Case group represented lower hospitalization rate and lower need for Coronary Artery Angiography (CAG) in comparison with control group. Mean cost in case group was significantly lower than control group (175.15$ vs. 391.33$, P < 0.001). In one year follow- up no cases of mortality or major cardiovascular events as cardiac infraction were found in discharged patients in case group. our study showed that rest SPECT fulfillment in admitted patients in emergency department was validated method for assessing patients' risk which avoids unnecessary hospitalizations and additional costs.

Single-Photon Emission Computed Tomography Myocardial Ischemia Detection in High-Risk Asymptomatic Patients: Correlation with Coronary Calcium Score and High-Sensitivity C-Reactive Protein.

Background:The association between myocardial ischemia in high-risk patients with coronary calcium score (CCS) and high-sensitivity C-reactive protein (hs-CRP) is not well established.Aims:We evaluated the correlation between hs-CRP, CCS, and myocardial ischemia in asymptomatic high-risk patients without known coronary artery disease (CAD).Materials and Methods:We prospectively assessed 68 asymptomatic high-risk outpatients without known CAD. One-day rest-stress Tc-99m single-photon emission computed tomography (SPECT) myocardial perfusion imaging and multislice computed tomography were performed. Multivariate regression analysis was performed for the assessment of predictors of myocardial ischemia. Standard risk factors and hs-CRP values were analyzed.Results:CCS >0 Agatston score was observed in 26 patients (46.4%). Seven patients had CCS between 10 and 99 AU, 8 patients between 100 and 400 AU, and 11 patients had CCS >400 AU. Mild ischemia was noted in 11 patients, moderate ischemia in 10 patients, and severe ischemia in 6 patients. Hs-CRP was >1 mg/L in 39 patients, of whom 8 patients had CCS >0, 13 patients had normal SPECT results, 6 patients had mild ischemia, and 12 patients had moderate and severe ischemia. Multivariate regression analysis showed independent predictors for increased CCS: low-density lipoprotein cholesterol (odds ratio [OR]: 2.891; P = 0.001); age >70 years (OR: 2.568; P = 0.001); and smoking (OR: 1.931; P = 0.001). We found hs-CRP to be an independent predictor of myocardial ischemia (OR: 4.145; 95% confidence interval: 1.398–7.471, P = 0.001).Conclusion:hs-CRP was an independent predictor of myocardial ischemia. hs-CRP might improve the selection of high-risk asymptomatic patients for myocardial SPECT imaging.

Miyokart Perfüzyon Sintigrafisinde Koroner Arter Lezyonlarının Lokalizasyonunun Total Perfüzyon Defekti Üzerine Etkisi

Introduction: In the present study, we analyzed patients with stable coronary artery disease (SCAD) by quantitative myocardial perfusion scintigraphy and evaluated the effect of different coronary lesion locations on total perfusion deficit (TPD).Patients and Methods: A total of 133 consecutive patients with SCAD who underwent myocardial perfusion imaging single photon emission computed tomography (SPECT) and conventional coronary angiography according to SPECT results were included in the study. TPD was used as the automated quantification variable.Results: Of the patients, 61 had significant coronary artery disease, and 72 had normal coronary arteries. For the normal, left anterior descending artery (LAD), circumflex artery (CX), and right coronary artery (RCA) groups, the median values were 7% vs. 11% vs. 10% vs. 9%, 4% vs. 6% vs. 7% vs. 4%, and 3% vs. 5% vs. 6% vs. 3% for stress TPD (sTPD), rest TPD (rTPD), and ischemic TPD (iTPD), respectively. There was no statistically significant difference in quantitative analysis (sTPD, rTPD, and iTPD) between the LAD, CX, and RCA groups (p> 0.05).Conclusion: TPD obtained by quantitative analysis method can be used for all coronary artery lesion location.

MRI assessment of left ventricle myocardial viability in patients with chronic coronary artery disease in comparison with single photon emission computed tomography

Background: Coronary artery disease (CAD) is highly prevalent in developed countries and is a leading cause of death. Diagnostic imaging plays an important role in the proper assessment and management of CAD. Myocardial perfusion is evaluated by SPECT in most patients today; however, this technique exposes patients to radiation and its diagnostic accuracy is sometimes limited by relatively low spatial resolution and artifacts from photon scatter and tissue attenuation. Scintigraphy defects may not be apparent until 10 g of tissue is infarcted. Thus, because a sizable threshold of damage is required, SPECT may miss small or subendocardial MI. Advances in rapid magnetic resonance imaging technology and its application to cardiac imaging have shown that MR imaging has tremendous potential for evaluation of cardiac disease. Practical advantages of cardiac MRI include the lack of ionizing radiation, a shortened examination time (25 to 40 min), good safety and tolerability profile, and detection of small subendocardial infarcts. Aim: assessment of myocardial viability in patients with chronic coronary artery disease by magnetic resonance imaging in comparison with single photon emission computed tomography (SPECT). Patients and Methods: This prospective study include examination of 10 adult patients (each patient has 3 coronary arteries, so we examined 30 coronary arteries and their myocardial territories) known to have chronic ischemic heart disease in Cairo university by MRI and SPECT with conventional angiography as a standard reference. MRI done by using 1.5T machine, using SENSE (sensitivity encoding) cardiac coil (6 element phased-array coil, receive only), functional cine images, first pass perfusion images and delayed enhancement images were acquired. SPECT study was done by 2-day exercise/rest gated SPECT imaging with Tc–99m sestamibi. Conventional coronary angiography was done using a trans-femoral approach to selectively inject the left and right coronary systems sequentially. The results of cardiac MRI subdivided into three groups: (a) Myocardial ischemia was defined as: either 1- Cardiac segment with motion abnormality or perfusion deficit at first-pass perfusion MR imaging consistent with no hyper-enhancement at delayed-enhancement MR imaging. Or 2- Cardiac segment of subendocardial enhancement (25 % thickness scar) with motion abnormality. (b) Myocardial scarring is defined as: either 1- Cardiac segment with myocardial delayed enhancement having ≥ 75% thickness scar. Or 2- Myocardial thickness less than 6 mm in diastole. (c) Mixed myocardial ischemia and scarring is defined as: Cardiac segment with myocardial delayed enhancement of near 50 % (>25% and <75%) thickness scarring. The results of SPECT were obtained by comparison between resting and exercise images to detect areas with fixed defects (scar) and those with reversible defects (ischemia). A defect was considered to be fixed (scarred) when there was no change between the stress and rest images, partially reversible (mixed ischemia and scar) when there was an improvement in tracer uptake of at least 1 grade between stress and rest images, totally reversible (ischemic) when there was normalization of uptake at rest images. In coronary angiography a reduction of the luminal diameter 70% or more in a major epicardial coronary artery or the major branches was considered to be a relevant stenosis. The angiographic results were classified as one-, two-, or three-vessel disease. Results:Both CMR and SPECT are accurate in detection of diseased coronary arteries with statistically significant P values. The overall patient based sensitivity, specificity, PPV, NPV and accuracy of cardiac MRI for the detection of diseased coronary artery were 94% (15 of 16 territories), 100% (14 of 14), 100% (15 of 15), 93% (14 of 15) and 97% (29 out of 30) respectively while the overall sensitivity, specificity, PPV, NPV and accuracy of SPECT for the detection of coronary artery stenosis were 88% (14 of 16), 93% (13 of 14), 93% (14 of 15), 87% (13 of 15) and 90% (27 out of 30) respectively. Both modalities CMR and SPECT show no statistically significant difference in detection of ischemic and scarred left ventricle myocardial segments although the sensitivity of MRI was higher than SPECT in detection of transmural scarring. As regard detection of complications CMR detected 1 intraventricular thrombus that was missed by SPECT. Conclusion: CMR is an accurate tool for assessment of coronary artery disease and myocardial viability as regard ischemia, scarring with great capability for detection of transmural extension of scarring and prediction of recovery. MRI can detect complications like ventricular thrombus that was missed by SPECT. Other advantages of MRI are time saving, lack of ionizing radiation and detection of left ventricular volumetrics and wall motion abnormalities. *= radiodiagnosis department, ^=internal medicine department- faculty of medicine-sohag unevirsity.

Radioiodinated Pentixather for SPECT Imaging of Expression of the Chemokine Receptor CXCR4 in Rat Myocardial-Infarction-Reperfusion Models.

The purpose of this study is to develop a specific CXCR4-targeting radioiodinated agent (125I- or 131I-pentixather) for single-photon-emission-computed-tomography (SPECT) imaging of CXCR4 expression in myocardial-infarction-reperfusion (MI/R) rat models. After SPECT-CT imaging with 125I-pentixather at 4, 12, and 36 h and 3 and 7 days after MI/R, the models were validated by ex vivo autoradiography, TTC staining, and immunohistochemistry and in vivo echocardiography and classical 99mTc-MIBI perfusion imaging. The SPECT-CT images showed that the infarcted myocardium (IM) could be visualized with high quality as early as 4 h and reached the maximum at 3 days after MI/R and that CXCR4 upregulation was still visible at 7 days after MI/R. In the biodistribution study, high uptakes in the IM (0.99 ± 0.13, 1.52 ± 0.29, 1.75 ± 0.22, 1.94 ± 0.27, and 0.61 ± 0.14% ID/g at 4, 12, and 36 h and 3 and 7 days after MI/R, respectively) were observed that were much higher than that of normal myocardium. The highest uptake was reached at 3 days after MI/R, which agreed well with the SPECT results. In addition, the radioactivity uptakes of the IM in both the biodistribution and SPECT imaging could be blocked effectively by excess amounts of AMD3465, indicating the high specificity of radioiodinated pentixather to CXCR4. On the basis of its promising properties, 125I-pentixather may serve as a powerful CXCR4-expression diagnostic probe for evaluating lesions and monitoring therapy responses in patients with cardiovascular diseases.

Improvement in Left Ventricular Function with Intracoronary Mesenchymal Stem Cell Therapy in a Patient with Anterior Wall ST-Segment Elevation Myocardial Infarction

Background/AimsThe progression and development of congestive heart failure is still considered a large problem despite the existence of revascularization therapies and optimal, state-of-the-art medical services. An acute myocardial infarction (AMI) is a major cause of congestive heart failure, so researchers are investigating techniques to complement primary percutaneous coronary intervention (PCI) or thrombolytic therapy to prevent congestive heart failure after AMI.MethodsTwenty-six patients with successful PCI for acute ST-segment elevation anterior wall myocardial infarction were assigned to either a control group (n = 12) or a bone marrow mesenchymal stem cells (BM-MSC) group (n = 14). The control group received optimum post-infarction treatment, and the BMSC group received intracoronary delivery of autologous BMSC at 1 month after PCI with the optimum medical treatment. The primary endpoint was a left ventricular ejection fraction (LVEF) change from baseline to 4-month follow-up, as determined via myocardial single-photon emission computed tomography (SPECT).ResultsThe global LVEF at baseline (determined 3.5 ± 1.5 days after PCI) was 35.4 ± 3.0% in the control group and 33.6 ± 4.7% in the BM-MSC group. BMSC transfer enhanced left ventricular systolic function primarily in anterior wall myocardial segments adjacent to the LAD infarcted area. Four months later, via SPECT, global LVEF had increased by 4.8 ± 1.9% in the control group and 8.8 ± 2.9% in the BM-MSC group (p = 0.031). The cell transfer did not increase the risk of adverse clinical events, in-stent restenosis, or proarrhythmic effects. The echocardiographic evaluation also revealed a significant increase in the LVEF value from baseline to the 4-month (9.0 ± 4.7 and 5.3 ± 2.6%, p = 0.023) and 12-month (9.9 ± 5.2% and 6.5 ± 2.7%, p = 0.048) follow-up in the BM-MSC group but not in the control group.ConclusionsIntracoronary administration of autologous BM-MSC was tolerable and safe with significant improvement in LVEF at 4-month (SPECT and echocardiography result) and 12-month (echocardiography result only) follow-up in patients with anterior AMI.