Screening for optimal parameters for modified pharyngeal electrical stimulation for the treatment of dysphagia after stroke in rats.

Pharyngeal electrical stimulation (PES), a novel noninvasive peripheral nerve stimulation technique, can effectively improve neurogenic dysphagia and increase the safety and effectiveness of swallowing in the clinic. However, the lack of animal models for dysphagia has limited the mechanistic research on PES, which affects its wide application. Therefore, determining optimal parameters for PES in rats is needed to enable mechanistic studies. Modified PES (mPES), which has different waves and pulse widths from PES, was used; in previous studies mPES was found to have a neurological mechanism like that of PES. A poststroke dysphagia (PSD) model was established, and rats with dysphagia were grouped into three different intensities (0.1 mA, 0.5 mA, and 1 mA) for the selection of optimal intensity and three different frequencies (1 Hz, 2 Hz, and 5 Hz) for the selection of optimal frequency based on a stimulation duration of 10 min in the clinic. A Videofluroscopic Swallow Screen (VFSS) was used to assess swallowing function in rats before and after mPES treatment. The results showed that the 1 mA group had better swallowing function (p < 0.05) than the model group. Compared with the model group, the 1 Hz and 5 Hz groups had the same improvement in swallowing function (p < 0.05). However, the increase in excitatory signals in the sensorimotor cortex was more pronounced in the 5 Hz group than in the other frequency stimulation groups (p < 0.05). Combining the clinical findings with the above results, we concluded that the optimal stimulation parameter for mPES in rats is "frequency: 5 Hz, current intensity: 1 mA for 10 min/day", which provides a basis for future basic experimental studies of mPES in animals.

Association between plasma long-chain polyunsaturated n-3 fatty acids concentrations and cognitive function: findings from NHANES III.

Background: With increased life expectancy, cognitive decline has emerged as a prevalent neurodegenerative disorder. Objective: This study aimed to examine the correlation between concentrations of Plasma long-chain n-3 polyunsaturated fatty acids (LCPUFAs) and cognitive performance in elderly Americans. Methods: Data were analyzed from older adults enrolled in two NHANES cycles. Participants completed four cognitive assessments, including the Immediate Recall Test (IRT), Delayed Recall Test (DRT), Animal Fluency Test (AFT), and Digit Symbol Substitution Test (DSST). Linear regression and restricted cubic spline modeling examined associations between plasma LCPUFAs levels and cognitive test outcomes. Results: The cohort included 610 adults aged 69 years on average, 300 (49.2%) males and 310 (50.8%) females. The median LCPUFAs concentration was 309.4 µmol/L, with an interquartile range of 244.7-418.9 µmol/L. In unadjusted and adjusted generalized linear regression model analyses, circulating LCPUFAs exhibited significant positive correlations with DRT performance. No relationships were detected among those with chronic conditions (chronic heart failure, stroke, diabetes). A significant association between LCPUFAs levels and DRT scores was evident in males but not females. Conclusion: Plasma LCPUFAs concentrations were significantly associated with DRT performance in males free of chronic illnesses, including heart failure, stroke, and diabetes.

A causal relationship between panic disorder and risk of alzheimer disease: a two-sample mendelian randomization analysis.

BACKGROUND: Observational studies have suggested a link between panic disorder (PD) and Alzheimer disease (AD). This study aimed to identify the underlying association of PD with the risk of AD using Mendelian randomization. METHODS: Genetic instrumental variables (IVs) were retrieved in the genome-wide association study between PD and AD. Then, five different models, namely inverse variance weighting (IVW), weighted median, weighted mode, MR-Egger and MR-robust adjusted profile scores (MR-RAPS), were used for MR Analysis. Finally, the heterogeneity and pleiotropy of identified IVs were verified by multiple sensitivity tests. RESULTS: The Cochran's Q test based on MR Egger and IVW showed that no evidence of heterogeneity was found in the effects of instrumental variables, so a fixed-effect model was used. IVW analysis (OR 1.000479, 95% CI [1.000147056, 1.000811539], p = 0.005) indicated that PD was associated with an increased risk of AD, and a causal association existed between them. Meanwhile, weighted median (OR 1.000513373, 95% CI [1.000052145, 1.000974814], p = 0.029) and MR-RAPS (OR 1.000510118, 95% CI [1.000148046, 1.00087232], p = 0.006) also showed the similar findings. In addition, extensive sensitivity analyses confirmed the robustness and accuracy of these results. CONCLUSION: This investigation provides evidence of a potential causal relationship between PD and the increased risk of AD. Based on our MR results, when diagnosing and treating patients with PD, clinicians should pay more attention to their AD-related symptoms to choose therapeutic measures or minimize comorbidities. Furthermore, the development of drugs that improve both PD and AD may better treat patients with these comorbidities.

Activation of Beta-adrenergic Receptors Upregulates the Signal-to-Noise Ratio of Auditory Input in the Medial Prefrontal Cortex and Mediates Auditory Fear Conditioning.

Norepinephrine (NE) is involved in auditory fear conditioning (AFC) in posttraumatic stress disorder (PTSD). However, it is still unclear how it acts on neurons. We aimed to investigate whether the activation of the ß-adrenergic receptor (ß-AR) improves AFC by sensitization of the prelimbic (PL) cortex at the animal, cellular, and molecular levels. In vivo single-cell electrophysiological recording was used to characterize the changes in neurons in the PL cortex after AFC. Then, PL neurons were locally administrated by the ß-AR agonist isoproterenol (ISO), the GABAaR agonist muscimol, or intervened by optogenetic method, respectively. Western blotting and immunohistochemistry were finally used to assess molecular changes. Noise and low-frequency tones induced similar AFC. The expression of ß-ARs in PL cortex neurons was upregulated after fear conditioning. Microinjection of muscimol into the PL cortex blocked the conformation of AFC, whereas ISO injection facilitated AFC. Moreover, PL neurons can be distinguished into two types, with type I but not type II neurons responding to conditioned sound and being regulated by ß-ARs. Our results showed that ß-ARs in the PL cortex regulate conditional fear learning by activating type I PL neurons.

SYNJ1 rescues motor functions in hereditary and sporadic Parkinson's disease mice by upregulating TSP-1 expression.

This study aimed to explore the role of SYNJ1 in Parkinson's disease (PD) and its potential as a neuroprotective factor. We found that SYNJ1 was decreased in the SN and striatum of hSNCA*A53T-Tg and MPTP-induced mice compared to normal mice, associated with motor dysfunction, increased α-synuclein and decreased tyrosine hydroxylase. To investigate its neuroprotective effects, SYNJ1 expression was upregulated in the striatum of mice through injection of the rAdV-Synj1 virus into the striatum, which resulted in the rescue of behavioral deficiencies and amelioration of pathological changes. Subsequently, transcriptomic sequencing, bioinformatics analysis and qPCR were conducted in SH-SY5Y cells following SYNJ1 gene knockdown to identify its downstream pathways, which revealed decreased expression of TSP-1 involving extracellular matrix pathways. The virtual protein-protein docking further suggested a potential interaction between the SYNJ1 and TSP-1 proteins. This was followed by the identification of a SYNJ1-dependent TSP-1 expression model in two PD models. The coimmunoprecipitation experiment verified that the interaction between SYNJ1 and TSP-1 was attenuated in 11-month-old hSNCA*A53T-Tg mice compared to normal controls. Our findings suggest that overexpression of SYNJ1 may protect hSNCA*A53T-Tg and MPTP-induced mice by upregulating TSP-1 expression, which is involved in the extracellular matrix pathways. This suggests that SYNJ1 could be a potential therapeutic target for PD, though more research is needed to understand its mechanism.

Network Pharmacology and Molecular Docking to Unveil the Mechanism of Shudihuang against Amyotrophic Lateral Sclerosis.

BACKGROUND: Shudihuang has been clinically proven to be an effective Chinese medicine compatible with the treatment of amyotrophic lateral sclerosis. However, the underlying mechanism of Shudihuang against amyotrophic lateral sclerosis remains unclear. OBJECTIVES: The present study aims to elucidate the possible mechanism of Shudihuang in treating ALS using network pharmacology and molecular docking. METHODS: The primary active components of Shudihuang and their relevant targets were identified by the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and the Swiss Target Prediction database, respectively. The ALS-related targets were obtained from the Disgenet and OMIM databases. The shared targets were derived by the intersection of disease-associated and component-associated targets and then introduced into the Cytoscape software to construct a network of drug-component-target. In addition, protein interaction relationships among the shared targets were analyzed by the STRING and Cytoscape software. Furthermore, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) functional enrichment analysis were conducted by the Metascape platform. The binding activities between the hub targets and the active components were assessed with molecular docking. RESULTS: Stigmasterol and sitosterol were identified as the core components of Shudihuang, and the hub targets of ALS are PTGS2, PPARG, ESR1, IGF-1R, and MAPK3, with the highest degrees in the PPI network. The finding that stigmasterol and sitosterol had a good affinity with PTGS2, PPARG, ESR1, IGF-1R, and MAPK3 also supported this. Finally, it was revealed that Shudihuang treatment of ALS predominantly involves estrogen- related pathways such as nuclear receptor activity and steroid binding. CONCLUSION: In summary, this study suggested that the main active components of Shudihuang (stigmasterol and sitosterol) may exert a critical effect in ALS treatment by binding to hub targets (PTGS2, PPARG, ESR1, IGF-1R, and MAPK3) and then modulating estrogen receptor-related pathways to attenuate glutamate excitotoxicity, inhibit oxidative stress and antagonize inflammation.

Establishment of a staging model for Parkinson's disease in mice.

The Parkinson's disease is the second most common neurodegenerative disease with different pathological mechanisms at each stage. To investigate Parkinson's disease further, this study was proposed to develop a continuous staging mouse model of Parkinson's disease to reproduce the pathological features of different stages of Parkinson's disease. We successively treated the mice with MPTP, and assessed the behavioral performance of the mice with the open field test and the rotarod test, and detected the aggregation of α-syn and the expression of TH protein in the substantia nigra of the mice with western blot test and immunofluorescence test. The results showed that the mice injected with MPTP for 3 days had no significant behavioral changes, no significant α-syn aggregation, but reduced TH protein expression and 39.5% loss of dopaminergic neurons in the substantia nigra, similar to the performance in the prodromal phase of Parkinson's disease. However, the behavior of the mice continuously treated with MPTP for 14 days was significantly altered, with significant α-syn aggregation, significant reduction in TH protein expression, and 58.1% loss of dopaminergic neurons in the substantia nigra, corresponding to the early clinical stage of Parkinson's disease. In the mice that were exposed to MPTP for 21 days, the motor impairment was more obvious, the α-syn aggregation was more significant, the reduction of TH protein expression was more evident, and the loss of dopaminergic neurons reached 80.5% in the substantia nigra, showing a clinical progression similar to that of Parkinson's disease. Consequently, this study found that continuous treatment of C57/BL6 mice with MPTP for 3, 14 and 21 days could construct mouse models of prodromal, early clinical and clinical progressive stages of Parkinson's disease, respectively, providing a promising experimental model foundation for the study of the different stages of Parkinson's disease.

Evaluation of left ventricular volumes and ejection fraction by 99mTc-MIBI gated SPECT and 18F-FDG gated PET in patients with prior myocardial infarction.

BACKGROUND: This study aimed to compare the accuracy of gated-SPECT (GSPECT) and gated-PET (GPET) in the assessment of left ventricular (LV) end-diastolic volumes (EDVs), end-systolic volumes (ESVs) and LV ejection fractions (LVEFs) among patients with prior myocardial infarction (MI). METHODS: One hundred and sixty-eight consecutive patients with MI who underwent GSPECT and GPET were included. Of them, 76 patients underwent CMR in addition to the two imaging modalities. The measurements of LV volumes and LVEF were performed using Quantitative Gated SPECT (QGS), Emory Cardiac Toolbox (ECTB), and 4D-MSPECT (4DM). RESULTS: The correlation between GPET, GSPECT, and CMR were excellent for LV EDV (r = 0.855 to 0.914), ESV (r = 0.852 to 0.949), and LVEF (r = 0.618 to 0.820), as calculated from QGS, ECTB, and 4DM. In addition, subgroup analysis revealed that EDV, ESV, and LVEF measured by GPET were accurate in patients with different extents of total perfusion defect (TPD), viable myocardium, and perfusion/metabolic mismatch. Furthermore, multivariate regression analysis identified that mismatch score was associated with the difference in EDV (P < 0.05) measurements between GPET and CMR. CONCLUSIONS: In patients with MI, LV volumes and LVEF scores measured by both GSPECT and GPET imaging were comparable to those determined by CMR, but should not be interchangeable in individual patients.

Preserved myocardial viability in patients with chronic total occlusion of a single coronary artery.

OBJECTIVE: To assess the benefits of coronary collateral circulation on myocardial perfusion, viability and function in patients with total occlusion of a single coronary artery using the 99mTc-sestamibi SPECT and 18F-fluorodeoxyglucose PET. METHODS: 164 Consecutive patients were included who underwent coronary angiography results exhibited total occlusion of a single coronary artery and received 99mTc-MIBI SPECT and 18F-FDG PET within 90 days of angiography. Myocardial perfusion and viability in patients with collateral circulation and those without it were compared. Long-term follow-up was performed through a review of patient clinical records. RESULTS: Collateral circulation was present in 56 patients (34%) and absent in 108 patients (66%). The total perfusion defect size in patients with collateral circulation decreased when compared to those without (30% ± 13% to 35% ± 14%, P < .05). The myocardial viability was 22% ± 12% in patients with collateral circulation, and 12% ± 9% in those without (P < .001). The left ventricular ejection fraction was higher, and the end-diastolic and end-systolic left ventricular volumes were lower in patients with collateral circulation (39% ± 11%, 138 ± 66, 89 ± 57) compared to patients without collateral circulation (31% ± 9%, 177 ± 55, 125 ± 48, all P < .001, respectively). Multi-factor logistic regression identified that concerning the variables of sex, age, viable myocardium, collateral circulation, treatment type and others, only treatment type was significantly associated with therapeutic effects (OR 3.872, 95% CI 1.915-7.830, P < .001). CONCLUSION: Collateral circulation can preserve resting myocardial blood perfusion and myocardial viability, and help maintain the function of the left ventricular myocardium. The appropriate treatment strategy will have a substantial impact on the therapeutic outcome.

Complete revascularization determined by myocardial perfusion imaging could improve the outcomes of patients with stable coronary artery disease, compared with incomplete revascularization and no revascularization.

OBJECTIVES: To compare the outcomes among patients treated by complete coronary revascularization (CCR) or incomplete coronary revascularization (ICR) and no coronary revascularization (NCR) by myocardial perfusion imaging (MPI), as well as to evaluate the impact of severity of ischemia on patients with coronary artery disease (CAD) by different therapy strategies. BACKGROUND: Using myocardial ischemia severity determined by MPI guiding treatment strategies for CAD patients still lacks strong clinical evidences. METHODS: Consecutive patients (N = 286) underwent clinical stress-rest SPECT MPI and were retrospectively followed-up. For assessment of outcome of treatment, all patients were classified into three groups (CCR, ICR, and NCR), and further divided into two subgroups as mild ischemia (< 10% ischemic myocardium) and moderate-severe ischemia (≥ 10% ischemic myocardium). All-cause death was defined as the primary endpoint, and the composite of deaths, nonfatal myocardial infarction, and repeat revascularization (MACE) as the secondary endpoint. RESULTS: Two-hundred eighty-six patients were followed-up for 46 ± 21 months. Thirty deaths and 65 MACEs were recorded. Patients treated by revascularization had significantly lower MACE (P < .001) but not mortality (P = .158) than patients treated by NCR. Outcomes of CCR related to mortality rate were greater than ICR and NCR (death: P = .019, MACE: P < .001). In patients with moderate-severe ischemia, CCR showed improved outcomes than ICR and NCR (death: P = .034; and MACE: P < .001). In patients with mild ischemia, the outcomes of CCR, ICR, and NCR had no significant difference (P > .05). Multivariate regression Cox analysis revealed that summed difference score [death: HR 1.09 (1.03, 1.15), P = .004] was an independent risk factor and CCR was an independent negative predictor [death: HR 0.31 (0.12, 0.81), P = .017; MACE: HR 0.30 (0.16, 0.57), P < .001]. CONCLUSIONS: Outcomes of patients treated by CCR were most likely more promising in comparison with treatment of ICR and NCR, especially when patients had over 10% ischemic myocardium.

Impact of incomplete revascularization of coronary artery disease on long-term cardiac outcomes. Retrospective comparison of angiographic and myocardial perfusion imaging criteria for completeness.

BACKGROUND: Coronary revascularization in patients with coronary artery disease may be guided by coronary angiography (CA) or alternatively by ischemia on stress myocardial perfusion imaging (MPI). Which strategy leads to optimal cardiac outcomes is uncertain. METHODS: We performed a retrospective analysis of 170 patients with MPI ischemia and percutaneous coronary intervention. The primary endpoint was all-cause mortality at a mean follow-up of 47 ± 21 months; the secondary end point was the composite of deaths, nonfatal myocardial infarction, and repeat coronary revascularization (MACE). The coronary revascularization was defined as complete (CCR) or incomplete (ICR) as judged by CA criteria and by MPI ischemia matched with CA criteria. RESULTS: Nighty-two patients (54%) had ICR by CA criteria (ICR-CA) and 84 (49%) had ICR by MPI criteria (ICR-MPI). Mortality and MACE were lower in patients with CCR-MPI than with ICR-MPI (P = .048, and P = .025). Survival of patients with CCR-CA and ICR-CA was not different (P = .081). Patients with both ICR-MPI and ICR-CA had the worst survival, whereas patients with CCR-MPI and CCR-CA had the best survival (P = .047). By multivariate analysis, ICR-MPI + ICR-CA was an independent predictor of death (P = .025). CONCLUSION: Patients with ICR by MPI were at higher risk than those with CCR. Patients with both ICR by MPI and CA were at the highest risk, while patients with CCR by both MPI and CA had the best long-term event-free survival.

Septal and anterior reverse mismatch of myocardial perfusion and metabolism in patients with coronary artery disease and left bundle branch block.

The effects of left bundle branch block (LBBB) on left ventricular myocardial metabolism have not been well investigated. This study evaluated these effects in patients with coronary artery disease (CAD).Sixty-five CAD patients with complete LBBB (mean age, 61.8 ±â€Š9.7 years) and 65 without LBBB (mean age, 59.9 ±â€Š8.4 years) underwent single photon emission computed tomography, positron emission tomography, and contrast coronary angiography. The relationship between myocardial perfusion and metabolism and reverse mismatch score, and that between QRS length and reverse mismatch score and wall motion score were evaluated.The incidence of left ventricular septum and anterior wall reverse mismatching between the two groups was significantly different (P < 0.001 and P = 0.002, respectively). The incidences of normal myocardial perfusion and metabolism in the left ventricular lateral and inferior walls were also significantly different between the two groups (P < 0.001 and P < 0.001, respectively). The incidence of septal reverse mismatching in patients with mild to moderate perfusion was significantly higher among those with LBBB than among those without LBBB (P < 0.001). In CAD patients with LBBB, septal reverse mismatching was significantly more common among those with mild to moderate perfusion than among those with severe perfusion defects (P = 0.002). The correlation between the septal reverse mismatch score and QRS length was significant (P = 0.026).In patients with CAD and LBBB, septal and anterior reverse mismatching of myocardial perfusion and metabolism was frequently present; the septal reverse mismatch score negatively correlated with the QRS interval.

Electrocardiographic profile of adenosine pharmacological stress testing.

Adenosine stress testing in conjunction with radionuclide myocardial perfusion imaging has become a common approach for the detection of coronary artery diseases in patients who are unable to perform adequate levels of exercise. However, specific electrocardiographic alterations during the test have been rarely described. Using a Chinese population, the aim of the present study was to provide a detailed electrocardiographic profile of adenosine stress testing. The study population included 1,168 consecutive outpatients who had undergone adenosine-induced stress myocardial perfusion imaging. Electrocardiographic data during and immediately following the adenosine infusion were collected, and the corresponding myocardial perfusion images were assessed. During adenosine infusion, 174 transient and 47 persistent arrhythmic events occurred in 110 patients (9.42%). Furthermore, frequent premature atrial contractions occurred in 65 individuals and frequent premature ventricular contractions were observed in 73 individuals. Atrioventricular block (AVB) occurred in 75 patients [first degree (I°) AVB, 16; second degree (II°) AVB, 58; third degree AVB, 1), while sinoatrial block occurred in eight patients. ST depression emerged in 69 patients. Patients with a baseline I° AVB had an increased risk of a II° AVB, and patients exhibiting baseline ST depression were more likely to have a further depressed ST segment during the stress test (odds ratio, 28.68 and 5.01, respectively; both P<0.001). Following adenosine infusion, 10 patients (0.86%) exhibited newly occurred arrhythmic events. However, no patient presented with acute myocardial infarction or sudden mortality. In conclusion, the results demonstrated that adenosine infusion was a safe method, despite the relatively high incidence of arrhythmic events. The majority of arrhythmias that occurred during infusion were transient, were reversible with the termination of infusion and did not indicate abnormal perfusion results.

The impacts of severe perfusion defects, akinetic/dyskinetic segments, and viable myocardium on the accuracy of volumes and LVEF measured by gated 99mTc-MIBI SPECT and gated ¹8F-FDG PET in patients with left ventricular aneurysm: cardiac magnetic resonance imaging as the reference.

BACKGROUND: To compare the accuracy of end-diastolic and end-systolic volumes (EDV, ESV) and LV ejection fraction (LVEF) measured by both GSPECT and GPET, using cardiac magnetic resonance imaging (CMR) as a reference. Furthermore, the impacts of severe perfusion defects, akinetic/dyskinetic segments, and residual viable myocardium on the accuracy of LV functional parameters were investigated. METHODS: Ninety-six consecutive patients with LV aneurysm and LV dysfunction (LVEF 32 ± 9%) diagnosed by CMR were studied with GSPECT and GPET. EDV, ESV, and LVEF were calculated using QGS software. RESULTS: Correlations of volumes were excellent (r 0.81-0.86) and correlation of LVEF was moderate (r 0.65-0.76) between GSPECT vs CMR and between GPET vs CMR. Compared with CMR, ESV was overestimated by GSPECT (P < .01) and underestimated by GPET (P < .0001); EDV was underestimated by GPET (P < .001); LVEF was underestimated by GSPECT but overestimated by GPET (both P < .001). Multivariate regression analysis revealed that the number of segments with severe perfusion defects (P < .001) was the only independent factor which was correlated to the EDV difference between GSPECT and CMR, the number of akinetic/dyskinetic segments with absent wall thickening (WT) was the only independent factor which was significantly correlated to the differences of ESV and LVEF measurements between GSPECT vs CMR and between GPET vs CMR (P < .0001), respectively. Neither the mismatch score nor the segments with viable myocardium were correlated to the differences of LV volumes and LVEF measurements between different imaging modalities. CONCLUSIONS: In LV aneurysm patients, LV volumes and LVEF measured by both GSPECT and GPET imaging correlated well with those determined by CMR, but should not be interchangeable in individual patients. The accuracy of LVEF measured by GSPECT and GPET was affected by the akinetic/dyskinetic segments with absent WT.

Ventilation/perfusion scintigraphy in children with post-infectious bronchiolitis obliterans: a pilot study.

PURPOSE: Childhood post-infectious bronchiolitis obliterans (BO) is an infrequent lung disease leading to narrowing and/or complete obliteration of small airways. Ventilation and perfusion (V/Q) scan can provide both regional and global pulmonary information. However, only few retrospective researches investigating post-infectious BO involved V/Q scan, the clinical value of this method is unknown. This preliminary prospective study was aimed to evaluate the correlation of V/Q scan with disease severity, pulmonary function test results, and prognosis in children with post-infectious BO. METHODS: Twenty-five post-infectious BO children (18 boys and 7 girls; mean age, 41 months) underwent V/Q scan and pulmonary function tests. Patients were followed after their inclusion. Ventilation index and perfusion index obtained from V/Q scan were used to measure pulmonary abnormalities. Spearman's rank correlation test of ventilation index and perfusion index on disease severity, lung function tests indices, and follow-up results were performed. RESULTS: The median follow-up period was 4.6 years (range, 2.2 to 5.0 years). Ventilation index and perfusion index were both correlated with disease severity (r = 0.72, p<0.01 and r = 0.73, p<0.01), but only ventilation index was related to pulmonary function tests results (all p<0.05). In addition, Spearman test yielded significant correlations between perfusion index and prognosis (r = 0.77, p<0.01), and ventilation index and prognosis (r = 0.63, p = 0.01). CONCLUSIONS: For children with post-infectious BO, the present study preliminarily indicated that the degree of ventilation and perfusion abnormalities evaluated by V/Q scan may be used to assess disease severity, and may be predictive of patient's outcome.

Evaluation of left ventricular myocardial perfusion and function using gated SPECT in patients with hypertrophic obstruction cardiomyopathy following percutaneous transluminal septal myocardial ablation.

OBJECTIVE: This study was designed to evaluate the left ventricular myocardial perfusion and function in hypertrophic obstruction cardiomyopathy patients following percutaneous transluminal septal myocardial ablation (PTSMA) using rest single-photon emission computed tomography (SPECT) myocardial perfusion imaging. PATIENTS AND METHODS: Thirty-five patients (24 men and 11 women, 48±11 years old) with hypertrophic obstruction cardiomyopathy underwent rest-gated Tc-MIBI SPECT imaging 4±10 days before (baseline) and 4.7±1.0 days (short-term) and 15.5±8.2 months (mid-term) after PTSMA. Semiquantitative and QGS quantitative evaluations of perfusion and function were carried out in 17 left ventricular segments. RESULTS: Myocardial perfusion of the septum following PTSMA was significantly reduced compared with baseline in all patients (P<0.05), but the myocardial perfusion in the basal septum was significantly higher at mid-term compared with short-term following PTSMA (P<0.05). Left ventricular ejection fraction was significantly decreased following PTSMA (P<0.05). Regional wall motion assessed in the basal anterior, basal septum, and basal inferior areas following PTSMA was significantly reduced compared with baseline (P<0.05), and wall thickening of the interventricular septum was decreased following PTSMA (P<0.05). CONCLUSION: Rest-gated SPECT imaging can be used to assess left ventricular myocardial perfusion and function and to investigate the efficacy of PTSMA during follow-up.

Comparison of coronary CT angiography and stress/rest myocardial perfusion SPECT imaging in a Chinese population.

INTRODUCTION: The relationship between luminal stenosis measured by coronary CT angiography and stress-induced ischemia by SPECT myocardial perfusion imaging is not clearly defined. The aims of this study were to evaluate the relationship between stenosis severity by coronary CT angiography and abnormal SPECT finding and to explore the impact of clinical factors on this relationship. PATIENTS AND METHODS: Seven hundred six consecutive patients with suspected coronary artery disease between January 2008 and October 2010 were prospectively enrolled. RESULTS: SPECT revealed 348 reversible and 58 fixed defects in 91 patients. Coronary CT angiography revealed that 339 patients had a maximal luminal stenosis 50% or greater. Total coronary artery calcium score was calculated in 428 patients, including 193 without calcification as well as 128 with mild, 59 with moderate, and 48 with severe-to-extensive calcification. Sensitivity, specificity, positive predictive value and negative predictive value (NPV) of coronary CT angiography for detecting abnormal SPECT finding were, respectively, 48.4%, 90.4%, 42.7%, and 92.2% on a patients' level and 40.2%, 95.6%, 33.6%, and 96.6% on vascular level when cutoff value of stenosis was set at 75%. Receiver operating characteristic analysis showed that the best cutoff value of stenosis for detecting abnormal SPECT finding was 55% on patients' level and 43% on vascular level. Patients with severe-to-extensive calcification had lowest specificity (56.3%) and NPV (69.2%). The sensitivity and positive predictive value of coronary CT angiography were not affected by any clinical factors (P = nonsignificant), whereas the specificity was higher in female patients, population younger than 60 years, and population without hypertension or family history of coronary artery disease (P < 0.05), and the NPV was higher among female patients and population without hypertension (P < 0.05). CONCLUSIONS: Coronary CT angiography has good agreement with stress/rest myocardial perfusion SPECT imaging. Coronary calcification and several clinical factors could affect the specificity and NPV of coronary CT angiography for detecting abnormal SPECT finding.

Left ventricular functional changes after adenosine vasodilator stress evaluated by gated single-photon emission computed tomography.

OBJECTIVES: Gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging is useful in assessing left ventricular (LV) myocardial perfusion and function. This study evaluated the LV functional changes after adenosine vasodilator stress, using gated SPECT. METHODS: The study population consisted of 70 patients who underwent adenosine-mediated stress and rest SPECT. All patients underwent coronary angiography. Semi-quantitative assessment of perfusion was analyzed and produced the summed rest score (SRS), the summed stress score (SSS) and the summed difference score (SDS). The global LV function parameters [ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV)] and regional LV function [the summed motion score (SMS) and the summed thickening score (STS)] were quantified by gated SPECT. RESULTS: Patients were divided into 2 groups: group 1 comprised 16 patients with worsening of LVEF (LVEFrest-LVEFado ≥5%), and group 2 comprised the other 54 patients. Compared with group 2, patients in group 1 had a significantly higher SSS and SDS (9.1 ± 6.8 vs. 5.6 ± 4.5 and 6.6 ± 3.8 vs. 3.6 ± 4.0, respectively; p < 0.05) and the severity of coronary artery stenosis was more serious (p < 0.05). CONCLUSION: Worsening of LVEF after adenosine-induced vasodilator stress, as shown by (99m)Tc-MIBI gated SPECT, is a valuable nonperfusion marker of significant CAD.

A high-normal thyrotropin level is associated with the severity of left ventricular diastolic dysfunction in patients with hypertrophic cardiomyopathy.

BACKGROUND: Impaired left ventricular (LV) diastolic function is a common pathophysiological feature of patients with hypertrophic cardiomyopathy (HCM). High-normal thyrotropin (thyroid-stimulating hormone, TSH) levels may alter the performance of the left ventricle. AIM: To ascertain whether the severity of impaired LV diastolic function in HCM patients might worsen with elevating TSH levels within the reference range. METHODS: This study included 152 HCM patients and 119 healthy controls with euthyroidism. Blood samples were taken to test for serum TSH, free triiodothyronine (FT3) and free thyroxine (FT4) levels. LV diastolic function was quantified by determining the ratio of the transmitral early LV filling velocity to the early diastolic mitral annulus velocity (E/Ea ratio). RESULTS: The E/Ea ratio was significantly higher in patients with high-normal TSH levels (25.7 ± 5.6 vs. 17.7 ± 4.9, p < 0.001). There was a significant correlation between the E/Ea ratio and the TSH levels within the high reference range (ß = 0.268, p = 0.021). Univariate logistic regression showed that high-normal TSH levels were predictors of severe heart failure. However, after adjusting for the effect of LV diastolic dysfunction, high-normal TSH levels were no longer independent predictors of severe heart failure. CONCLUSIONS: The HCM patients with high-normal TSH levels had a higher degree of LV diastolic dysfunction. Mild TSH level changes within the high reference range can influence the severity of impaired LV diastolic function. In HCM patients, high-normal TSH levels may affect the development of heart failure through their association with LV diastolic impairment.