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Objective: To evaluate the value of I-2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl) nortropane (I-FP-CIT) dopamine transporter single photon emission computed tomography (DAT-SPECT) to change management strategies of patients suspected of parkinsonism., Method: This was an institutional review board-approved, retrospective study. DAT-SPECT scans ordered by movement disorder specialist and neurologists from 2011-2014 were reviewed. Clinical data and radiological reports of 173 patients suspected of parkinsonism were reviewed. The DAT-SPECT scan results were correlated with clinical assessment and treatment changes., Results: A total of 173 patients (104 male and 69 female subjects; age, 64.4 ± 12.6 years) suspected of parkinsonism were included. Median duration of symptoms was 36 months (range, 1-480 months). Scans were most often requested when there was diagnostic uncertainty in clinical features (59.6%, 103/173) or to differentiate one other disease from parkinsonism such as Parkinson disease (PD) versus essential tremor (23.7%, 41/173), PD versus drug-induced parkinsonism (8.7%, 15/173), or PD versus psychogenic (6.4%, 11/173) or vascular (1.7%, 3/173) disorders. Patients were classified, according to the DAT-SPECT scanning results, as those with abnormal DAT-SPECT findings (59%, 102/173) and those with normal DAT-SPECT findings (41%, 71/173). In patients with normal DAT-SPECT findings, follow-up management data were available in 76.1% (54/71). The management changed in 39.4% (28/54) after DAT scan with starting a new appropriate medications or supportive therapy in 4.2% (3/28), withholding inappropriate dopaminergic treatment in 11.3% (8/28), or continuing observation in 23.9% (17/28). In patients with abnormal DAT-SPECT findings, follow-up management data were available in 78.4% (80/102). There was change in management of 37.3% (38/80), a new PD treatment was started in 89.5% (34/38). The dose of medication was adjusted in 5.3% (2/38), although the original treatment was not changed. Parkinson disease treatment was stopped in 2.6% (1/38) and discontinued in 2.6% (1/38) based on clinical decision of neurologists despite abnormal DAT-SPECT findings., Conclusions: DAT-SPECT findings impacted treatment decisions in 44.7% of patients suspected of Parkinsonism.

We report myocardial perfusion SPECT pattern in four subsequent patients with rate dependent left bundle branch block (LBBB). Three females and one male (aged 48, 51, 63 and 67 years) were studied. None of the patients had history of typical chest pain and all suffered from atypical chest pain or dyspnea on exertion. All patients were tested for baseline and serial heart rate, blood pressure, and electrocardiogram recordings. The exercise treadmill tests (ETT) were carried out under the strict supervision of a cardiologist, a nuclear medicine physician and close availability of an expert cardio-pulmonary resuscitation team and cardiac care unit within just few seconds. Maximal stress test (at least 85% of calculated heart rate, following development of LBBB) was achieved in all four patients according to standard Bruce protocol. No adverse cardiac events were noted and all ETT stress protocols terminated completely and safely. Myocardial perfusion SPECT imaging showed no evidence of reversible perfusion defects. The only patient with past history of exercise induced LBBB showed nonreversible perfusion defects in the septal and anteroseptal regions and mild LV cavity dilatation. The limited number of patients enrolled in our study does not allow us to draw a definite conclusion. Despite the presence of false-positive defects in myocardial perfusion SPECT in patients with sustained LBBB, such a finding is not a consistent finding in patients with rate dependent or exercised-induced LBBB, unlike that which we expected to see. Maybe it is possible to continue ETT for those patients undergoing myocardial perfusion scintigraphy and developing rate dependent LBBB.

Introduction: Appropriateness of referrals for myocardial perfusion imaging (MPI) in developing countries has not been extensively studied. Our study was conducted to describe the ordering practices of physicians and appropriateness of MPI referrals in Iran., Method: We prospectively applied 2005 and 2009 versions of the Appropriateness Use Criteria published by the American College of Cardiology Foundation (ACCF) and the American Society of Nuclear Cardiology (ASNC) to 291 consecutive patients (age 55.3 ± 10.3 years) who underwent SPECT-MPI. For this purpose, we convened a panel, consisting of two academic cardiologists, one academic clinician in internal medicine, and one academic clinician in nuclear medicine. The panelists were invited for a face-to-face meeting to judge appropriateness of SPECT-MPI and independently assign a specific indication (scenario), whenever possible, for each case in accordance with ACCF/ASNC appropriateness scenarios., Results: Based on the 2005 ACCF/ASNC criteria, SPECT-MPI studies were judged appropriate for 211 (72.5%), uncertain for 36 (12.4%), inappropriate for 32 (11.0%), and unclassifiable for 12 (4.1%) referrals. The same figures based on the 2009 version were 219 (75.3%), 15 (5.2%), 49 (16.8%), and 8 (2.7%) patients, respectively. Overall agreement between the 2005 and 2009 versions was good (κ 0.63). Lack of chest pain and age below 60 years were significant indicators increasing the likelihood of inappropriate referrals by 2.9-3.4 fold. Absence of diabetes mellitus and hypertension, a normal lipid profile, lack of a past history of myocardial infarction or cardiovascular interventions (CABGs or PCI), as well as lack of application and exercise ECG stress test as the gate keeper (keeping abnormal ETT or inability of the patient to perform exercise as the appropriate indication for SPECT-MPI referral) were significant indicators, decreasing the odds of appropriate referrals. Generally a higher percentage of referrals with inappropriate indications had normal MPI., Conclusion: Our study provides an evidence for the fact that SPECT-MPI ordering practices in our developing community largely parallel the ACCF/ASNC recommendations. The implementation of appropriateness criteria is feasible in clinical settings and might provide an alternative to utilization management.

A 61-year-old man with chronic chest pain was referred for a myocardial perfusion scan. Following dipyridamole infusion, 99mTc-MIBI was injected and the reconstructed images showed decreased activity in the anteroseptal wall, which prompted the supervising physician to review the cinematic data. Reviewing the cinematic images revealed abnormal 99mTc-MIBI uptake by the ribs, clavicles, and more intensely in the sternum. The next morning, whole-body planar imaging was performed 20 minutes after injection of 99mTc-MIBI at rest, which again revealed widespread abnormal 99mTc-MIBI uptake. Subsequently, a skull X-ray showed multiple areas of osteolysis, typical of punched-out lesions. In view of this evidence, the patient underwent bone marrow aspiration, which revealed marked plasmocytosis and confirmed the diagnosis of multiple myeloma. Our case indicates a false positive perfusion defect induced by sternal sestamibi uptake secondary to sternal tumoral involvement. As the sternum is in close proximity to the myocardium, the effects of its unusual radiotracer uptake on the pattern of myocardial perfusion can be significant. The interpretation of a myocardial perfusion scan should not be limited to the heart and, as the ultimate goal is the patient's wellbeing, any available information should be interpreted.

Background: Mustard agents are of the major chemical agents used during Iran-Iraq war. There are no reports concerning long-term cardiac effects. The aim was to assess the scintigraphic pattern of myocardial perfusion in patients intoxicated with blistering gases., Method: We analyzed myocardial perfusion scans of 22 consecutive intoxicated patients (21 male and 1 female, all < 44 years) and compared results with 14 controls. Only those patients and controls were entered whose 10-year risk of coronary artery disease (Framingham criteria) was <5%. Also only those patients were experimented upon that had currently other confirmed complications of intoxication (respiratory, cutaneous and ocular complications). All patients underwent a 1-day stress and rest protocol using (99m)Tc-MIBI. Images were assessed visually and quantitatively using Cedars Sinai program., Results: The prevalence of nonhomogeneity of uptake and left and right ventricular enlargement in both visual and quantitative analyses were higher in the mustard exposed patients than unexposed controls. The prevalence of ischemia was higher in the exposed patients (P < 0.05). Cavity to myocardium ratio, as an established and validated measure of ejection fraction, was also significantly lower in the warfare patients than the controls., Conclusion: In so far it lies in our knowledge, this is the first report concerning the scintigraphic pattern of myocardial perfusion in mustard intoxicated patients. Based on the results, the pattern of myocardial perfusion in these patients is significantly different from normal controls, which could resemble either coronary artery disease or mild cardiomyopathic changes.

Background: Left ventricular ejection fraction (EF) is a major determinant of survival in patients with coronary artery disease (CAD). Comparative accuracy of numerous modalities in calculating EF is not well investigated., Method: We compared EF as calculated by rest and post-stress Cedars automated quantitative gated SPECT (AQGS), rest and post-stress semi-automatically processed gated SPECT (MQGS), echocardiography and contrast ventriculography (LVG) to those determined by rest and post-stress cavity-to-myocardium ratio (CMR) in 109 patients. Gated SPECT was performed based on a 2-day protocol using Tc-MIBI., Results: Mean EF in LVG, echo, post-stress CMR, rest CMR, post-stress AQGS, rest AQGS, post-stress MQGS and rest MQGS were 41.8%+/-12.1, 44.8%+/-11.8, 38.1%+/-10.7, 35.7%+/-12.1, 44.5%+/-15.1, 46.9%+/-14.7, 40.1%+/-14.3 and 43.5%+/-14.3 respectively. Although significant differences were observed between some of these methods, good and excellent linear correlations were present among values (all Pearson correlations >0.63). Considering LVG as the 'gold standard', we defined two groups: EF <35% (class 1) and >35% (class 2). Discriminant analysis showed that SPECT has the ability to predict patients' classes. In 4/18 of patients with normal SPECT (on both visual and quantitative analyses, SSS <4), EF on QGS showed a significant decrease on post-stress compared with rest., Conclusion: There is a good correlation in calculating EF by LVG, QGS and echocardiography, regardless of EF value. Whenever QGS is impossible, CMR is a reliable indirect indicator of EF. Gating of both phases (and when impossible, CMR of both phases) has an additional value in diagnosis of CAD.

Background: Limited available data indicate that a specific pattern of increased gastric wall radiotracer uptake is associated with dyspepsia. Our purpose was to evaluate the frequency of this finding and its relation with dyspeptic evidences., Method: 1056 consecutive outpatients referred for myocardial perfusion SPECT were interviewed concerning the dyspeptic symptoms, current gastric medications and previous gastroduodenal interventions. The intensity of gastric wall activity was graded qualitatively as G1 or hyperactive gastric wall (equivalent to the patient's heart activity) and G2 (less than heart activity)., Results: The pattern of gastric wall hyperactivity was identified in 1.9% of patients. Dyspeptic symptoms were present in 80 and 18.6% of G1 and G2 patients, respectively (p<0.001). The dyspeptic symptoms were classified as ulcer-like in 37.5%, dysmotility-like in 43.75% and GERD-like in 18.75% of the dyspeptic G1 patients. Considering the classification of dyspepsia, there was no significant difference between the dyspeptic patients of groups. The history of previous gastroduodenal interventions and current use of gastric medications was significantly higher among G1 patients., Conclusion: The infrequent pattern of gastric wall hyperactivity could be clinically important and can identify a category of patients, who require additional diagnostic gastrointestinal investigation to specify another possible noncardiac origin of complaints.