123I-MIBG Myocardial Scintigraphy Research Articles

SGLT2-inhibitors reduce the cardiac autonomic neuropathy dysfunction and vaso-vagal syncope recurrence in patients with type 2 diabetes mellitus: the SCAN study

BackgroundIn patients with type 2 diabetes mellitus (T2DM) the vaso-vagal syncope (VVS) recurrence could be due to the alteration of autonomic system function, evaluated by heart rate variability (HRV), and by 123I-metaiodobenzylguanidine (123I-mIBG) myocardial scintigraphy indexes: Heart to Mediastinum ratio (H/Mlate), and Washout rate (WR). The SGLT2-I could modulate/reduce autonomic dysfunction in T2DM patients with VVS. This effect could reduce the VVS recurrence in T2DM patients. MethodsIn a prospective multicenter study, after propensity score matching, we studied a population of 324 T2DM patients with VVS, divided into 161 SGLT2-I-users vs. 163 Non-SGLT2-I users. In these patients as SGLT2-I-users vs. Non-SGLT2-I users, we investigated the HRV and 123I-MIBG modifications and VVS recurrence at 12 months of follow-up. ResultsAt follow-up end, the SGLT2-I-users vs. Non-SGLT2-I users had best glucose homeostasis and lower values of inflammatory markers, and resting heart rate (p < 0.05). The SGLT2-I-users vs. Non-SGLT2-I users evidenced the lowest low frequency/high frequency ratio (LF/HFr), a significant difference for all the indexes of autonomic dysfunction via ECG Holter analysis, and higher values of H/Mlate (p < 0.05). Finally, comparing SGLT2-I-users vs. Non-SGLT2-I users, we found a higher rate of VVS recurrence events, specifically of the vasodepressor VVS recurrence at 1-year follow-up (p < 0.05). We did not find a significant difference of mixed and cardio-inhibitory VVS recurrence events at 1 year of follow-up in the study cohorts (p > 0.05). At the Cox regression analysis H/Mlate (0.710, [0.481–0.985]), and SGLT2-I therapy (0.550, [0.324–0.934]) predicted all causes of syncope recurrence at 1 year of follow-up. ConclusionsNon-SGLT2-I users vs. SGLT2-I-users had alterations of the autonomic nervous system, with a higher rate of VVS recurrence at 1 year of follow-up. The indexes of cardiac denervation predicted the VVS recurrence, while the SGLT2-I reduced the risk of VVS recurrence.Clinical trial registration number: NCT03717207.

Autopsy Validation of the Diagnostic Accuracy of 123I-Metaiodobenzylguanidine Myocardial Scintigraphy for Lewy Body Disease.

Background and Objectives123I-meta-iodobenzyl-guanidine (123I-MIBG) myocardial scintigraphy is used as a diagnostic imaging test to differentiate Lewy body diseases (LBDs), including Parkinson disease and dementia with Lewy bodies, from other similar diseases. However, this imaging test lacks validation of its diagnostic accuracy against the gold standard. Our aim was to validate the diagnostic accuracy of 123I-MIBG myocardial scintigraphy for LBD against autopsy, the gold standard.MethodsThis retrospective, cross-sectional study included consecutive autopsy patients from the Brain Bank for Aging Research who had undergone 123I-MIBG myocardial scintigraphy. We compared the 123I-MIBG myocardial scintigraphy findings with autopsy findings. Furthermore, the proportion of residual tyrosine hydroxylase (TH)–immunoreactive sympathetic fibers in the anterior wall of the left ventricle was investigated to assess the condition of the cardiac sympathetic nerves assumed to cause reduced 123I-MIBG uptake in LBDs.ResultsWe analyzed the data of 56 patients (30 with pathologically confirmed LBDs and 26 without LBD pathology). Compared with the neuropathologic diagnosis, the early heart-to-mediastinum (H/M) ratio had a sensitivity and specificity of 70.0% (95% CI 50.6%–85.3%) and 96.2% (95% CI 80.4%–99.9%), respectively. The delayed H/M ratio had a sensitivity and specificity of 80.0% (95% CI 61.4%–92.3%) and 92.3% (95% CI 74.9%–99.1%), respectively. The washout rate had a sensitivity and specificity of 80.0% (95% CI 61.4%–92.3%) and 84.6% (95% CI 65.1%–95.6%), respectively. The proportion of residual TH-immunoreactive cardiac sympathetic fibers strongly correlated with the amount of cardiac 123I-MIBG uptake when assessed with early and delayed H/M ratio values (correlation coefficient 0.75 and 0.81, respectively; p < 0.001).DiscussionThis clinicopathologic validation study revealed that 123I-MIBG myocardial scintigraphy could robustly differentiate LBDs from similar diseases. Abnormal 123I-MIBG myocardial scintigraphy findings strongly support the presence of LBD and cardiac sympathetic denervation. However, LBD pathology should not necessarily be excluded by normal myocardial scintigraphy results, especially when other biomarkers suggest the presence of comorbid Alzheimer disease pathology.Classification of EvidenceThis study provides Class II evidence that 123I-MIBG myocardial scintigraphy accurately identifies patients with LBD.

Dynamic planar scintigraphy for the rapid kinetic measurement of myocardial 123I-MIBG turnover can identify Lewy body disease

BackgroundUsing two static scans for 123I-meta-iodobenzyl-guanidine (123I-MIBG) myocardial scintigraphy ignores the dynamic response from vesicular trapping in nerve terminals. Moreover, the long pause between scans is impractical for patients with Lewy body diseases (LBDs). Here, we optimized indices that capture norepinephrine kinetics, tested their diagnostic performance, and determined the differences in 123I-MIBG performance among disease groups.MethodsWe developed a new 30-min protocol for 123I-MIBG dynamic planar imaging for suspected LBD patients. Pharmacokinetic modelling of time-activity curves (TACs) was used to calculate three new indices: unidirectional uptake of 123I-MIBG to vesicular trapping (iUp), rate of myocardial 123I-MIBG loss (iLoss), and non-specific fractional distribution of 123I-MIBG in the interstitial space. We compared the performance of the new and existing indices with regard to discrimination of patients with or without LBDs. Subgroup analysis was performed to examine differences in 123I-MIBG turnover between patients in a dementia with Lewy bodies (DLB) group and two Parkinson’s disease (PD) groups, one with and the other without REM sleep behaviour disorder (RBD).ResultsiLoss was highly discriminative, particularly for patients with low myocardial 123I-MIBG trapping, and the new indices outperformed existing ones. ROC analysis revealed that the AUC of iLoss (0.903) was significantly higher than that of early HMR (0.863), while comparable to that of delayed HMR (0.892). The RBD-positive PD group and the DLB group had higher turnover rates than the RBD-negative PD group, indicating a potential association between prognosis and iLoss.Conclusion123I-MIBG turnover can be quantified in 30 min using a three-parameter model based on 123I-MIBG TACs. The discriminatory performance of the new model-based indices might help explain the neurotoxicity or neurodegeneration that occurs in LBD patients.

Influence of characteristics of epicardial adipose tissue and myocardial sympathetic innervation on the development of late recurrence of atrial fibrillation after radiofrequency ablation

Aim. To investigate the relationship between radiological characteristics of epicardial adipose tissue (EAT) and myocardial sympathetic activity, as well as to study their association with late recurrence of atrial fibrillation (AF) after radiofrequency ablation (RFA).Material and methods. This prospective study included 26 people with persistent and long-standing persistent AF scheduled for interventional AF treatment. Before the RFA procedure, all patients underwent cardiac 123I-metaiodobenzylguanidine (123I-MIBG) scintigraphy to assess the myocardial sympathetic innervation and contrast-enhanced cardiac multislice computed tomography to assess pulmonary vein anatomy, left atrial volume, and EAT volume. Clinical follow-up, including 12-lead electrocardiography (ECG) and 24-hour ECG monitoring, was carried out 3, 6 and 12 months after RFA.Results. After the end of follow-up, the patients were divided into two groups: with AF recurrence (group 1, n=8) and without AF recurrence (group 2, n=18). Multivariate logistic analysis found that only the 123I-MIBG washout rate (odds ratio, 1,0943; 95% confidence interval, 1,0138-1,1812) proved to be an independent predictor of late AF recurrence after RFA. ROC analysis revealed that a 123I-MIBG washout rate &gt;21% with a sensitivity of 75% and a specificity of 83,3% (AUC=0,844; p&lt;0,001) predicts late AF recurrence after RFA.Conclusion. Parameters of myocardial sympathetic activity, assessed by 123I-MIBG myocardial scintigraphy, are associated with late AF recurrence after RFA in patients with persistent and long-standing persistent AF. There were no reliable data confirming associations between myocardial sympathetic innervation and radiological EAT indicators, as well as the effect of the latter on the risk of AF recurrence after RFA.

157 WHOLE HIPPOCAMPAL VOLUMES AND HIPPOCAMPAL SUBFIELD VOLUMES IN MCI-LB AND MCI-ad

Abstract Background Mild cognitive impairment with Lewy bodies (MCI-LB) is the commonest prodromal phenotype of Dementia with Lewy Bodies (DLB) and may be challenging to differentiate from MCI due to Alzheimer’s disease (MCI-AD). Preservation of medial temporal lobe structures on MRI is recognised as a supportive biomarker consistent with underlying Lewy body disease rather Alzheimer’s disease (AD). We investigated whether whole hippocampal volume and differing hippocampal subfield atrophy patterns, could be used as a surrogate biomarker of underlying ad pathology, allowing for differentiation of MCI-LB from MCI-AD. Methods Participants were recruited to the following groups’: healthy controls (HC), MCI-LB and MCI-ad, all ≥60 years. Alongside detailed clinical, neuropsychological assessments, all participants underwent 3 T MRI, 123I-FP-CIT SPECT and 123I-MIBG myocardial scintigraphy. Using Freesurfer (v.6.0), a fully automated hippocampal subfield segmentation of the MRI data was performed. Results Groups consisted of 31 HC (mean age, 73.7 yrs; mean Mini-Mental state Examination [MMSE] score, 28.4), 34 MCI-LB (mean age, 74.7 yrs; mean MMSE score, 26.6) and 29 MCI-ad (mean age, 75.4 yrs; mean MMSE score, 27.1). There was no significant difference in whole hippocampal volume between MCI-LB and MCI-ad(Mean (SD) in mm3: MCI-LB 6025 (961) vs MCI-ad 5407 (882), p = 0.12) or between MCI-LB and HC (Mean (SD) in mm3: MCI-LB 6025 (961) vs HC 6355 (962), p = 0.11). Whole hippocampal volume was significantly smaller in MCI-ad compared with HC (p &amp;lt; 0.001). Comparison between MCI-LB and MCI-ad, showed absolute hippocampal subfield volumes were all lower in MCI-ad. However, the magnitude of the differences were small and no significant difference in hippocampal subfield volumes were noted between these groups, with the exception of the hippocampal tail being significantly smaller in MCI-ad compared to MCI-LB (p = 0.04). Conclusion In a well-characterised cohort, whole hippocampal and hippocampal subfield volumes were similarly atrophied in MCI-LB and MCI-ad and did not distinguish between the groups.

Prognostic usefulness of planar 123I-MIBG scintigraphic images of myocardial sympathetic innervation in congestive heart failure: Follow-Up data from ADMIRE-HF

BackgroundTo evaluate whether planar 123I-MIBG myocardial scintigraphy predicts risk of death in heart failure (HF) patients up to 5 years after imaging. Methods and ResultsSubjects from ADMIRE-HF were followed for approximately 5 years after imaging (964 subjects, median follow-up 62.7 months). Subjects were stratified according to the heart/mediastinum (H/M) ratio (< 1.60 vs ≥ 1.60) on planar 123I-MIBG scintigraphic images obtained at baseline in ADMIRE-HF. Cox proportional hazards models and Kaplan-Meier analyses were used to evaluate time to death, cardiac death, or arrhythmic events for subjects stratified by H/M ratio, baseline left ventricular ejection fraction (LVEF: < 25% and 25 to ≤ 35%), and by H/M strata within LVEF strata. All-cause mortality was 38.4% vs 20.9% and cardiac mortality was 16.8% vs 4.5%, in subjects with H/M < 1.60 vs ≥ 1.60, respectively (P < 0.05 for both comparisons). Subjects with preserved sympathetic innervation of the myocardium (H/M ≥ 1.60) were at significantly lower risk of all-cause and cardiac death, arrhythmic events, sudden cardiac death, or potentially life-threatening arrhythmias. Within LVEF strata, a trend toward a higher mortality for subjects with H/M < 1.60 was observed reaching significance for LVEF 25 to ≤ 35% only. ConclusionsDuring a median follow-up of 62.7 months, patients with H/M ≥ 1.60 were at significantly lower risk of death and arrhythmic events independently of LVEF values.

Prognostic value of myocardial MIBG scintigraphy in acute ischemic stroke

Abstract Funding Acknowledgements Type of funding sources: None. Background Autonomic dysfunction is a common complication of acute ischemic stroke and has been associated with poor functional outcome and increased mortality. We investigated the potential relation between the myocardial washout rate (WOR) of 123I-meta-iodobenzylguanidine (123I-mIBG), as a measure of cardiac sympathetic activity, and functional outcome in acute ischemic stroke. Methods 38 patients with ischemic stroke (11 females, 72 years old [61-81)), underwent myocardial 123I-mIBG scintigraphy within the first week after stroke onset. Early (10 minutes post-injection (pi)) and late (4 hours pi) planar scans of the thoracic region were made. Regions of interest (ROI) were drawn over the mediastinum and the heart, and heart-to-mediastinum ratio (HMR) was calculated. Myocardial WOR was calculated as follows: (ROI heart early – ROI heart late)/ (ROI heart early) x 100%. Counts were corrected for background and counts in ROI heart late were corrected for decay. Patients were divided in 2 groups: those with a good functional outcome, defined as modified Rankin Scale (mRS) ≤ 2 at 3 months after stroke (i.e., patient is functionally independent), and those with a poor functional outcome, defined as a mRS &amp;gt; 2. Results Median WOR was 27,4 % (IQR 10,4-43,6). In univariate analysis, poor functional outcome after stroke was associated with age, stroke severity on admission (measured by the National Institutes of Health Stroke Scale (NIHSS)), beta-blocker use before and during hospitalization, WOR and late HMR. In subsequent multivariate analysis WOR (OR 1.087; 95% CI 1.003-1.177, p = 0.042) was an independent predictor of poor stroke outcome even after adjustment for age and NIHSS. Conclusions In patients with acute ischemic stroke, myocardial washout of 123I-mIBG predicts stroke outcome, even after adjustment for age and stroke severity on admission.

Association between neurosarcoidosis with autonomic dysfunction and anti-ganglionic acetylcholine receptor antibodies

ObjectiveTo determine whether autonomic dysfunction in neurosarcoidosis is associated with anti-ganglionic acetylcholine receptor (gAChR) antibodies, which are detected in autoimmune autonomic ganglionopathy.MethodsWe retrospectively extracted cases of sarcoidosis from 1787 serum samples of 1,381 patients between 2012 and 2018. Anti-gAChR antibodies against the α3 and β4 subunit were measured by luciferase immunoprecipitation to confirm the clinical features of each case. We summarized literature reviews of neurosarcoidosis with severe dysautonomia to identify relevant clinical features and outcomes.ResultsWe extracted three new cases of neurosarcoidosis with severe dysautonomia, among which two were positive for anti-gAChR antibodies: Case 1 was positive for antibodies against the β4 subunit, and Case 2 was positive for antibodies against both the α3 and β4 subunits. We reviewed the cases of 15 patients with neurosarcoidosis and severe dysautonomia, including the three cases presented herein. Orthostatic hypotension and orthostatic intolerance were the most common symptoms. Among the various types of neuropathy, small fiber neuropathy (SFN) was the most prevalent, with seven of nine cases exhibiting definite SFN. Six of eight cases had impaired postganglionic fibers, of which the present three cases revealed abnormality of 123I-MIBG myocardial scintigraphy. Of the 11 cases, 10 were responsive to immunotherapy, except one seropositive case (Case 2).ConclusionsThe presence of gAChR antibodies may constitute one of the mechanisms by which dysautonomia arises in neurosarcoidosis.

Appropriate assessment method of 123I-MIBG myocardial scintigraphy for the diagnosis of Lewy body diseases and idiopathic REM sleep behavior disorder.

In 123I-metaiodobenzylguanidine (123I-MIBG) myocardial scintigraphy, the early heart-to-mediastinum (H/M) ratio is considered to reflect the density of the cardiac sympathetic nerve endings, washout rate (WR) is an indicator of the cardiac sympathetic tone, and the delayed H/M ratio reflects both. The Delayed H/M ratio is usually used to support the diagnosis of Lewy body diseases (LBDs) and idiopathic REM sleep behavior disorder (iRBD); however, which values should be used have not been specified. Here, we hypothesized that the combination of these values is appropriate for the diagnostic purpose. In this single-center retrospective cohort study, we recruited 106 patients with LBDs or iRBD and 33 patients without those diseases, of whom we reviewed the 123I-MIBG myocardial scintigraphy results. Sensitivity/specificity to diagnose LBDs and iRBD were 0.77/0.94 for the early H/M ratio (≤ 2.0), 0.82/0.94 for the delayed H/M ratio (≤ 2.0), and 0.89/0.91 for WR (≥ 23.0). When patients were considered positive if at least either the early H/M ratio or WR was abnormal, the sensitivity significantly increased to 0.97, whereas the specificity remained similar at 0.91. Furthermore, our subgroup analyses revealed that WR enhancement preceded H/M ratio reduction, but, in patients with a severely reduced early H/M ratio, paradoxically normal WR could be observed. We propose the highly sensitive, combined early H/M ratio and WR assessments for 123I-MIBG myocardial scintigraphy. The temporal precedence of cardiac sympathetic dysfunction over denervation and the floor effect in 123I-MIBG uptake may underlie the sensitivity improvement.

Is There Any Clinical Value of Adding 123I-Metaiodobenzylguanidine Myocardial Scintigraphy to 123I-Ioflupane (DaTscan) in the Differential Diagnosis of Parkinsonism?

The aim of the study is to evaluate the impact of myocardial I-metaiodobenzylguanidine (MIBG) in the diagnosis, clinical management, and differential diagnosis of Parkinson disease (PD) and non-PD parkinsonism. The study enrolled 41 patients with parkinsonism. An initial diagnosis was reached after thorough clinical and imaging evaluation. After 2 to 5 years of follow-up, a final diagnosis was established. All patients underwent, soon after their initial visit, presynaptic striatal DaT scintigraphy with I-FP-CIT (DaTscan) and I-MIBG myocardial scintigraphy. DaTscan is not specific to distinguish among different types of neurodegenerative parkinsonism. I-MIBG myocardial scintigraphy displays the functional status of cardiac sympathetic nerves, which is reduced in PD/dementia with Lewy bodies (DLB) and normal in atypical parkinsonian syndromes and secondary or nondegenerative parkinsonism. No patients showed adverse effects during or after both scintigraphies. A positive DaTscan was found in all patients in the PD/DLB group (17/17) and in 15 of 24 patients in the non-PD group. Myocardial I-MIBG scintigraphy was associated with lower sensitivity (82% vs 100%) but higher specificity than DaTscan (79% vs 38%) in diagnosis PD/DLB from non-PD parkinsonism. A positive scan result on both techniques, to confirm diagnosis of PD/DLB, significantly improved the specificity of DaTscan, from 38% to 75%, with no reduction in sensitivity. Myocardial I-MIBG imaging provides complementary value to I-FP-CIT in the proper diagnosis, treatment plan, and differential diagnosis between PD and other forms of parkinsonism.

A diagnostic strategy for Lewy body disease using DAT-SPECT, MIBG and Combined index.

The functional imaging methods widely used for the diagnosis of Lewy body disease (LBD) are 123I-N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl) nortropan (FP-CIT) with dopamine transporter single photon emission computed tomography (DAT-SPECT) and 123I-iodobenzylguanidine (MIBG) myocardial scintigraphy. The aim of this study was to determine whether DAT-SPECT or 123I-MIBG myocardial scintigraphy should be examined first and to evaluate whether the combined use of DAT-SPECT and MIBG myocardial scintigraphy is superior to using either modality alone for diagnosing suspected LBD. In this retrospective study, a total of 117 patients suspected of having LBD underwent DAT-SPECT imaging followed by MIBG myocardial scintigraphy. The delayed heart-to-mediastinum (H/M) ratio of MIBG scintigraphy, and the specific binding ratio (SBR) of DAT-SPECT imaging, and Combined index (defined as SBR mean×H/M in the delayed phase) were used as semi-quantitative measures. The diagnostic ability was evaluated using these indexes. The sensitivity, specificity, and accuracy of diagnosing Lewy body disease were 59.6%, 71.4%, and 67.5% by SBR mean of DAT-SPECT, 85.1%, 91.4%, and 88.9% by delayed H/M ratio of MIBG myocardial scintigraphy, 76.6%, 74.3%, and 75.2% by Combined index, respectively. In the diagnosis of LBD, DAT-SPECT, MIBG myocardial scintigraphy, and Combined index may be reliable indices. In particular, MIBG myocardial scintigraphy was the specific modality for LBD diagnosis. Understanding the effectiveness and limits of DAT-SPECT and MIBG myocardial scintigraphy and using both properly will lead to a more accurate diagnosis and better treatment.

The Prognostic Value of the Results of 123I-metaiodobenzylguanidine Myocardial Scintigraphy in the Examination of Patients with Atrial Fibrillation Referred for Its Interventional Treatment

Objective. To identify the scintigraphic predictors of the efficiency of interventional treatment for atrial fibrillation (AF) by cardiac 123I-metaiodobenzylguanidine (123I-MIBG) radionuclide scanning.Material and methods. The investigation enrolled 35 patients with AF concurrent with hypertensive disease (HD): 17 persons with persistent AF (PAF) and 18 patients with long-standing PAF (LPAF). In addition, 10 patients with HD without arrhythmia signs were examined as a comparison group. All the patients with AF before radiofrequency ablation (RFA) and those with sinus rhythm underwent 123I-MIBG myocardial scintigraphy to assess the sympathetic innervation of the heart. The efficiency of RFA was evaluated after 12 months by 24-hour ECG monitoring.Results. The patients of both groups were divided into subgroups according to the presence of recurrent arrhythmia one year after interventional treatment. ROC analysis could determine the main scintigraphic predictors of the efficiency of RFA. The preoperative indicators, in which the subgroups with and without recurrent AF showed significant differences, were studied. In the patients with PAF, the delayed Heart/ Mediastinum (H/M) ratio cutoff was ≥1.55 (the area under the ROC curve was 0.929; 100% sensitivity and 57% specificity), and the threshold value of 123I-MIBG washout rate was ≤22.3% (the area under ROC curve was 0.957; 100% sensitivity and 43% specificity) may suggest that RFA is effective. In the patients with LPAF, the threshold values of early H/M ratio were ≥1.69 (the area under the ROC curve was 0.849; 100% sensitivity and 62% specificity) and those of delayed H/M ratio were ≥1.66 (the area under the ROC curve was 0.938; 94% sensitivity and 23% specificity) allow the prediction of a risk for postoperative recurrent AF.Conclusion. The findings suggest that 123I-MIBG scintigraphy can be used to predict a high risk for recurrent AF after RFA of the pathological pathways of a pulse in the myocardium.

P2624Association between renal dysfunction and cardiac sympathetic innervation in patients with heart failure

Abstract Introduction In heart failure (HF) a strict interaction exists between heart and kidney. Previous studies reported a significant impact of sympathetic overdrive, that causes beta-adrenoceptor desensitization, in both renal and heart failure progression. It can be hypothesized that renal failure might be associated with impaired sympathetic activity assessed directly at the myocardial level in patients affected by HF. Purpose Aim of the present observational study was to assess the relationship between renal dysfunction and cardiac sympathetic innervation in HF patients with mildly and severely reduced ejection fraction (HFrEF and HFmEF). Methods Two-hundred and sixty-three patients (84% males; 66±10.8 years) with mild-to-severe HF (EF 31±6.8%) underwent iodine-123 meta-iodobenzylguanidine (123I-MIBG) myocardial scintigraphy to assess sympathetic innervation, evaluating early and late heart to mediastinum (H/M) ratios and washout rate. All patients also underwent clinical evaluation and venous blood sample collection for the assessment of serum creatinine and consequently the estimation of glomerular filtration rate (eGFR) by EPI formula. Results A direct correlation was found between EPI-eGFR and late H/M (r=0,215; p&lt;0.001) (figure 1), with an inverse correlation between NYHA class and late H/M (r=0,152; p=0.013), and a direct correlation between left ventricular EF and late H/M (r=0,348; p&lt;0.001). These results were not confirmed for early H/M, nor washout rate. Dividing the population in reduced eGFR and normal eGFR (cut-off ≤60 ml/min/1,73m2), a statistical significant reduction of late H/M value was found in patients with reduced eGFR (late H/M = 1,49±0,21) compared with patients with preserved eGFR (late H/M = 1,56±0,26) (p=0.020). In a multivariate model, adjusting eGFR for NYHA class and left ventricular EF, reduced eGFR and left ventricular EF remained significant predictors of reduced late H/M (p=0.006 and p&lt;0.001, respectively). Figure 1. linear regression curve Conclusions Patients with impaired renal function and HF show impaired cardiac sympathetic activity compared to HF patients with preserved renal function, and reduced eGFR estimated by EPI formula is a significant predictor of reduced late H/M evaluated by 123I-MIBG. Thus, in future studies, the combination of these two parameters might provide addictive prognostic information in HF patients.

CAPABILITIES OF &lt;sup&gt;123&lt;/sup&gt;I-MIBG SCINTIGRAPHY AND GATED BLOOD-POOL SPECT IN PREDICTING THE RESULTS OF CARDIAC RESYNCHRONIZATION THERAPY

Purpose.To assess the diagnostic value of scintigraphy parameters of sympathetic activity and mechanical dyssynchrony of the heart for prediction of the results of cardiac resynchronization therapy (CRT).Material and Methods.The study included 28 patients with functional class III (NYHA) chronic heart failure referred for CRT. Before operation, a set of scintigraphic studies was performed to evaluate mechanical dyssynchrony, the state of cardiac sympathetic innervation, and perfusion. Clinical status, volume indices, and contractility of both cardiac ventricles were evaluated 6 months after CRT. After that, all patients were divided into 2 groups: group 1 included CRT responders (n=15); group 2 comprised non-responders (n=13).Results. Significant differences between groups were found in the following baseline parameters: early heart-to-mediastinum ratio (H/M) (2.42 and 1.87; p&lt;0.05), delayed H/M (1.89 and 1.78; p&lt;0.05), left ventricular (LV) end-diastolic volume (EDV) (271 mL and 299 mL; p&lt;0.05); LV end-systolic volume (ESV) (206 mL and 227 mL; p&lt;0.05), and interventricular dyssynchrony (109 ms and 62 ms; p&lt;0.05). Responders showed a strong correlation between delayed H/M and LV dyssynchrony (–0.795, p&lt;0.05). According to logistic regression analysis, delayed H/M (OR=4.25; 95% CI 1.4–12.92; p&lt;0.5) and interventricular dyssynchrony (OR=1.01; 95% CI 1.003–1.03; p&lt;0.5) were statistically significant determinants of the response to CRT.Conclusion. 123I-MIBG myocardial scintigraphy can be used to predict the effectiveness of CRT. Delayed H/M ratio and interventricular dyssynchrony are the independent predictors of response to CRT.

Striatal dopamine activity and myocardial 123I-metaiodobenzylguanidine uptake in early Parkinson's disease

IntroductionDopamine transporter imaging and myocardial 123I-metaiodobenzylguanidine (123I-MIBG) scintigraphy have been widely used to diagnose and discriminate degenerative parkinsonism. Many studies have reported that both imaging findings are associated with a variety of motor and non-motor phenomena in Parkinson's disease (PD). However, the association between striatal dopamine activity and myocardial 123I-MIBG uptake has not been well investigated. The objective of this study is to identify the dopamine transporter activity of the corpus striatum and thalamus according to myocardial 123I-MIBG uptake in PD. MethodsNinety-six newly diagnosed, non-medicated PD patients were enrolled. All patients underwent 123I-MIBG myocardial scintigraphy, positron emission tomography (PET) using 18FN-(3-fluoropropyl)-2beta-carbon ethoxy-3beta-(4-iodophenyl) nortropane and T1-weighted magnetic resonance imaging (MRI). Patients were stratified into normal and decreased 123I-MIBG groups according to their delayed heart-to-mediastinum ratio (cutoff value = 1.78). After normalizing the PET images with spatially normalized MRI, the regional standardized uptake value ratios (SUVRs) were analyzed with a volume-of-interest template between the two groups. ResultsThirty-one patients showed normal myocardial 123I-MIBG uptake, and 65 patients showed reduced uptake. The SUVR of the globus pallidus in the group with reduced 123I-MIBG uptake was significantly lower than the SUVR in the normal 123I-MIBG uptake group. The heart-to-mediastinum ratio was correlated well with the SUVR of the globus pallidus, independent of age, disease duration, and the severity of motor symptoms. ConclusionEarly PD patients with normal 123I-MIBG uptake showed a relatively preserved dopamine reserve in the globus pallidus than patients with reduced 123I-MIBG uptake.

Prediction of ong-term ardiac vents by 123I-meta-odobenzylguanidine maging after acute yocardial nfarction and eperfusion herapy.

Objective(s):In heart failure, the heart-to-mediastinum (H/M) ratio of the delayed image and washout rate (WR) are well-known as a powerful cardiac event predictors. H/M ratio quantifies the accumulation rate of MIBG in the myocardium and WR quantifies reduction of meta-iodobenzylguanidine (MIBG) accumulation in the heart from the early planar image to the delayed planar images in the 123I-MIBG scintigraphy. The present study was conducted to estimate the role of the parameters of cardiac sympathetic imaging by 123I-MIBG myocardial scintigraphy in subacute phase of acute myocardial infarction (AMI) in the prediction of cardiac events, particularly in patients who are successfully responded to reperfusion therapy.Methods:This study was conducted on 145 patients with initial AMI who underwent 123I-MIBG myocardial scintigraphy and myocardial single-photon emission computed tomography (SPECT) after successful response to reperfusion therapy. The 123I-MIBG myocardial scintigraphy was averagely performed 16±5.8 days after the onset of AMI. The early image was taken 15 min after the intravenous administration of 123I-MIBG. Three hours after 123I-MIBG administration, an anterior planar delayed SPECT image was obtained. The H/M ratio and WR were calculated based on planar images. In addition, the average WR, defect volume, and extent were calculated from the SPECT image. The end points of the cardiac event was defined as hospitalization due to unstable angina, heart failure progression, myocardial infarction recurrence, malignant arrhythmia and cardiac death. Results:The follow-up period was 18.4±8.5 months on average, during which 38 (26.2%) cases experienced cardiac events. The results revealed a significant difference between the groups with and without cardiac events in terms of WR and WR (SPECT). Based on the multivariate analysis, WR was the only relevant factor predicting cardiac events. The cumulative event-free rate was significantly lower in the group with the delayed H/M ratio of < 1.74. The cumulative event-free rate were significantly lower in the groups with WR and WR (SPECT) more than 25% and 21.8%, respectively. There was no significant relationship between the cumulative event-free survival rate and the defect size. Conclusion:In the subacute phase of myocardial infarction, the increased WR of 123I-MIBG from the myocardium in planar scintigraphy and SPECT is the predictor of heart failure and cardiac events such as myocardial infarction and recurrence of unstable angina.

Exploration of cardiac sympathetic adrenergic nerve activity in narcolepsy

ObjectiveTo compare cardiac sympathetic adrenergic nerve activity in patients with narcolepsy type 1 (NT1) and controls using 123I-MIBG myocardial scintigraphy, and to determine the clinical and neurophysiological variables associated with 123I-MIBG scintigraphy results in NT1. MethodsFifty-six NT1 patients and 91 controls without neurological diseases underwent a cardiac scintigraphy. MIBG uptake was quantified by delayed heart/mediastinum (H/M) ratio. Clinical, neurophysiological and biological determinants of a low H/M were assessed in NT1. ResultsMIBG uptake did not differ between NT1 and controls in crude and adjusted associations. Five patients had low MIBG uptake (<1.42, first decile of controls), often with advanced age, cardiovascular (CV) diseases, stimulants intake, and REM sleep behavior disorder. Patients with H/M <1.62 (lowest tertile) were older, with higher BMI, microarousal index and CV comorbidities. A three-fold increase of phasic/tonic REM sleep motor activities was found in those patients, confirmed in a subanalysis of 40 drug-free patients. No association was found with CSF hypocretin levels. ConclusionA direct measure of the heart adrenergic nerve activity revealed no sympathetic denervation in NT1. SignificanceOur results indicate normal cardiac sympathetic innervation in NT1. However, few patients with low MIBG uptake also presented CV comorbidities and REM sleep motor deregulation, potentially at high CV risk, requiring a careful follow-up.

Prognostic values of 123I-MIBG myocardial scintigraphy and heart rate variability in patients with heart failure with preserved ejection fraction

BackgroundThe aim of this study was to evaluate the prognostic values of sympathetic nerve system using 123I-MIBG myocardial scintigraphy and using Holter electrocardiogram (ECG) in patients with heart failure with preserved ejection fraction (HFpEF). Methods and resultsAmong 403 consecutive patients with stable HF who underwent 123I-MIBG myocardial scintigraphy and Holter ECG, we identified 133 patients (64 ± 16 years) who had preserved ejection fraction (≥ 50%) by echocardiography. Multivariate Cox model was used to assess if washout rate (WR) by 123I-MIBG scintigraphy and very low frequency power (VLFP) by Holter ECG was associated with major adverse cardiovascular events (MACE). During a mean follow-up of 5.4 ± 4.1 years, 39 MACE occurred. The lower nighttime VLFP (HR 3.29, 95% CI 1.56 to 6.92) and higher WR (HR 4.01, 95% CI 1.63 to 9.88) were the significant prognostic factors for MACE. As compared to high nighttime VLFP and low WR group, MACE risk was significantly the highest in the low nighttime VLFP and high WR group (HR 40.832; 95% CI 5.378 to 310.012, P < 0.001). ConclusionThis study demonstrated that the nighttime VLFP adding to WR could be a potential prognostic value among patients with HFpEF.

Cerebrospinal fluid 5-HIAA concentrations correlate with cardiac uptake of 123I-MIBG during myocardial scintigraphy in drug naïve Parkinson's disease.

We examined the correlations between cerebrospinal fluid (CSF) concentrations of homovanillic acid (HVA) and 5-hydroxyindole acetic acid (5-HIAA) and imaging assessment scores, using 123I-Ioflupane SPECT and 123I-MIBG myocardial scintigraphy in 23 drug naïve PD patients. The CSF 5-HIAA concentration correlated with the H/M ratio of the delayed image (r = 0.458, p < 0.05) and the washout rate (r = - 0.642, p < 0.01) of 123I-MIBG myocardial scintigraphy. These correlations suggest some unclarified pathophysiological links between the central serotonergic and cardiac sympathetic systems.

Restless legs syndrome, leg motor restlessness and their variants in patients with Parkinson's disease and related disorders

ObjectiveThe objective of this study was to investigate the prevalence of restless leg syndrome (RLS), leg motor restlessness (LMR) and RLS/LMR variants and their relationship with clinical factors in patients with Parkinson's disease (PD) and related disorders. MethodsSixty-three PD patients, 17 multiple system atrophy (MSA) patients and 11 progressive supranuclear palsy (PSP) patients were included in this study. Through face-to-face interviews, the patients were diagnosed with RLS/LMR, or with RLS/LMR variants in which the symptoms occur predominantly in body parts other than the legs. ResultsThe frequency of RLS, LMR, RLS variants and LMR variants was as follows: PD (12.7%, 11.1%, 0% and 1.6%); MSA (5.9%, 11.8%, 0% and 0%); and PSP (0%, 9.1%, 0% and 0%). Restlessness without the urge to move was observed in 25.4% of the PD patients, 11.8% of the MSA patients and 0% of the PSP patients. The PD patients with restlessness exhibited higher Hoehn and Yahr stages and higher scores on the Scales for Outcomes in PD-Autonomic, PD sleep scale-2 and Beck Depression Inventory-II. The olfactory functioning, 123I-MIBG myocardial scintigraphy uptake and dopamine transporter single photon emission computed tomography findings did not differ between the PD patients with restlessness and those without. The severity of RLS was correlated with the autonomic symptoms among the PD patients with restlessness. ConclusionPD with restlessness was characterized by increased autonomic, sleep and depressive symptoms. Further studies including a large sample are warranted to characterize restlessness in PD and related disorders.