Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Previous fracture and subsequent fracture risk: a meta-analysis to update FRAX

A large international meta-analysis using primary data from 64 cohorts has quantified the increased risk of fracture associated with a previous history of fracture for future use in FRAX.

INTRODUCTION

The aim of this study was to quantify the fracture risk associated with a prior fracture on an international basis and to explore the relationship of this risk with age, sex, time since baseline and bone mineral density (BMD).

METHODS

We studied 665,971 men and 1,438,535 women from 64 cohorts in 32 countries followed for a total of 19.5 million person-years. The effect of a prior history of fracture on the risk of any clinical fracture, any osteoporotic fracture, major osteoporotic fracture, and hip fracture alone was examined using an extended Poisson model in each cohort. Covariates examined were age, sex, BMD, and duration of follow-up. The results of the different studies were merged by using the weighted β-coefficients.

RESULTS

A previous fracture history, compared with individuals without a prior fracture, was associated with a significantly increased risk of any clinical fracture (hazard ratio, HR = 1.88; 95% CI = 1.72-2.07). The risk ratio was similar for the outcome of osteoporotic fracture (HR = 1.87; 95% CI = 1.69-2.07), major osteoporotic fracture (HR = 1.83; 95% CI = 1.63-2.06), or for hip fracture (HR = 1.82; 95% CI = 1.62-2.06). There was no significant difference in risk ratio between men and women. Subsequent fracture risk was marginally downward adjusted when account was taken of BMD. Low BMD explained a minority of the risk for any clinical fracture (14%), osteoporotic fracture (17%), and for hip fracture (33%). The risk ratio for all fracture outcomes related to prior fracture decreased significantly with adjustment for age and time since baseline examination.

CONCLUSION

A previous history of fracture confers an increased risk of fracture of substantial importance beyond that explained by BMD. The effect is similar in men and women. Its quantitation on an international basis permits the more accurate use of this risk factor in case finding strategies.

A Risk Prediction Model for Severe Radiation Induced Lymphopenia in Patients with Pancreatic Cancer Treated with Concurrent Chemoradiotherapy

PURPOSE/OBJECTIVE(S)

In pancreatic cancer, radiation induced lymphopenia (RIL) is associated with a poor prognosis. However, normal tissue complication probability (NTCP) models predicting RIL in pancreatic cancer treated with concurrent chemoradiotherapy (CCRT) have yet to be developed. This study aims to develop a least absolute shrinkage and selection operator (LASSO)-based multivariate NTCP model to predict severe RIL in patients with pancreatic cancer during CCRT and to validate the model internally.

MATERIALS/METHODS

We retrospectively reviewed patients with localized pancreatic cancer who underwent CCRT using three-dimensional conformal radiation therapy from 2013 to 2021. The exclusion criteria were patients with distant metastasis; patients who did not complete RT due to tumor progression; patients who did not have absolute lymphocyte count (ALC) data available before or during RT. An ALC of < 0.5 K/μL during CCRT was defined as severe RIL. A NTCP model of severe RIL was developed by LASSO-based multivariate analysis. We used age, sex, Karnofsky performance status, maximum tumor size, carbohydrate antigen 19-9 level before RT, ALC before RT, volume of planning target volume (PTV), and dosimetric parameters for surrounding organs (including spleen, vertebrae, liver, bilateral kidneys, gastrointestinal tracts) as variables for LASSO. In addition, internal validation was performed by the bootstrap method. The predictive performance of the model was evaluated by the area under the curve (AUC) of the receiver operating characteristic curve and scaled Brier score.

RESULTS

Of the 131 patients included in the study, the median age was 68 years (range, 42-84), and 55% were male. The median ALC before RT was 1.37 K/µL (0.52-3.50). The median PTV volume was 315.4 ml (86.3-1079.3). The median dose of radiotherapy was 50.4 Gy (16.2-50.4), with 1.8 Gy per fraction. Combination chemotherapy was S-1 in 99 cases (75.6%) and gemcitabine in 32 cases (24.4%). Induction chemotherapy before CCRT was performed in 39 patients (29.8%). Severe RIL was observed in 84 (63.6%) patients. The LASSO showed that low baseline ALC (p = 0.0002), large PTV volume (p < 0.0001), and a large kidney V5 defined as the percentage of bilateral kidneys receiving 5 Gy or more (p = 0.0338) were selected as parameters of the prediction model for severe RIL (AUC = 0.917) and scaled Brier score was 0.511. As a result of internal validation by the bootstrap method, the average AUC was 0.918 (95% confidence interval, 0.849-0.954).

CONCLUSION

Severe RIL occurred frequently during CCRT for pancreatic cancer, and a NTCP model for severe RIL developed and validated internally in this study showed good predictive performance. External validation is needed before this NTCP model can be used as a benchmark for treatment planning to reduce the risk of severe RIL and for considering future treatment approaches.

Coexistence of Pheochromocytoma and Primary Aldosteronism due to Multiple Aldosterone-producing Micronodules in the Ipsilateral Adrenal Gland

A 46-year-old woman was referred for hypertension and a right adrenal tumor. Primary aldosteronism (PA) was suspected because of the high plasma aldosterone concentration-to-plasma renin activity ratio. However, a subsequent evaluation revealed coexistent PA and pheochromocytoma. We performed laparoscopic right adrenalectomy. Histology of the resected adrenal gland confirmed pheochromocytoma and multiple aldosterone-producing adrenocortical micronodules. Following adrenalectomy, the urinary catecholamine levels normalized, and hyperaldosteronism improved but persisted. Hypertension also improved but persisted and was normalized with spironolactone. The clinical course indicated that the PA lesions were likely bilateral. This was a histologically proven case of coexistent pheochromocytoma and PA due to multiple aldosterone-producing micronodules.

Case report: Impact of hyperthyroidism on psychotic symptoms in schizophrenia comorbid with Graves' disease

Introduction

Auditory hallucinations are the most common type of hallucinations observed in schizophrenia; however, visual hallucinations are not uncommon. In Graves' disease, depression, hypomania, and psychosis can occur. While the association between Graves' disease and psychosis has been explored, understanding of the specific impact of thyroid dysfunction severity on psychiatric symptom severity is limited. Here, we present a case report of a patient with schizophrenia comorbid with Graves' disease whose psychotic symptoms were impacted by hyperthyroidism.

Case

The patient was a 32-year-old Japanese woman who presented with auditory and visual hallucinations, agitation, and pressured speech. The patient was diagnosed with schizophrenia comorbid with Graves' disease and thyroid storm. The patient's psychotic symptoms were found to be associated with fluctuations in thyroid hormone levels, and visual hallucinations were observed only during thyroid storms. Treatment involved dexamethasone, potassium iodide, bisoprolol fumarate, and methimazole for thyrotoxicosis, and a blonanserin transdermal patch, paliperidone, and paliperidone palmitate for psychotic symptoms. The patient's auditory and visual hallucinations improved with antipsychotic treatment and decreased thyroid hormone levels.

Conclusion

This case highlights the importance of monitoring thyroid function in patients with schizophrenia, particularly those with comorbid Graves' disease. The correlation between psychiatric symptoms and thyroid hormone levels was demonstrated on an individual level over time, with symptoms worsening as thyroid hormone levels increased. Additionally, our case suggests that abnormally high thyroid hormone levels may trigger visual hallucinations in individuals with schizophrenia. Further studies are needed to elucidate the underlying mechanisms and potential treatment implications of this association.

O-linked N-acetylglucosamine modification is essential for physiological adipose expansion induced by high-fat feeding

Adipose tissues accumulate excess energy as fat and heavily influence metabolic homeostasis. O-linked N-acetylglucosamine (O-GlcNAc) modification (O-GlcNAcylation), which involves the addition of N-acetylglucosamine to proteins by O-GlcNAc transferase (Ogt), modulates multiple cellular processes. However, little is known about the role of O-GlcNAcylation in adipose tissues during body weight gain due to overnutrition. Here, we report on O-GlcNAcylation in mice with high-fat diet (HFD)-induced obesity. Mice with knockout of Ogt in adipose tissue achieved using adiponectin promoter-driven Cre recombinase (Ogt-FKO) gained less body weight than control mice under HFD. Surprisingly, Ogt-FKO mice exhibited glucose intolerance and insulin resistance, despite their reduced body weight gain, as well as decreased expression of de novo lipogenesis genes and increased expression of inflammatory genes, resulting in fibrosis at 24 weeks of age. Primary cultured adipocytes derived from Ogt-FKO mice showed decreased lipid accumulation. Both primary cultured adipocytes and 3T3-L1 adipocytes treated with OGT inhibitor showed increased secretion of free fatty acids. Medium derived from these adipocytes stimulated inflammatory genes in RAW 264.7 macrophages, suggesting that cell-to-cell communication via free fatty acids might be a cause of adipose inflammation in Ogt-FKO mice. In conclusion, O-GlcNAcylation is important for healthy adipose expansion in mice. Glucose flux into adipose tissues may be a signal to store excess energy as fat.NEW & NOTEWORTHY We evaluated the role of O-GlcNAcylation in adipose tissue in diet-induced obesity using adipose tissue-specific Ogt knockout mice. We found that O-GlcNAcylation in adipose tissue is essential for healthy fat expansion and that Ogt-FKO mice exhibit severe fibrosis upon long-term overnutrition. O-GlcNAcylation in adipose tissue may regulate de novo lipogenesis and free fatty acid efflux to the degree of overnutrition. We believe that these results provide new insights into adipose tissue physiology and obesity research.

Ketone bodies: A double-edged sword for mammalian life span

Accumulating evidence suggests health benefits of ketone bodies, and especially for longevity. However, the precise role of endogenous ketogenesis in mammalian life span, and the safety and efficacy of the long-term exogenous supplementation of ketone bodies remain unclear. In the present study, we show that a deficiency in endogenous ketogenesis, induced by whole-body Hmgcs2 deletion, shortens life span in mice, and that this is prevented by daily ketone body supplementation using a diet containing 1,3-butanediol, a precursor of β-hydroxybutyrate. Furthermore, feeding the 1,3-butanediol-containing diet from early in life increases midlife mortality in normal mice, but in aged mice it extends life span and prevents the high mortality associated with atherosclerosis in ApoE-deficient mice. By contrast, an ad libitum low-carbohydrate ketogenic diet markedly increases mortality. In conclusion, endogenous ketogenesis affects mammalian survival, and ketone body supplementation may represent a double-edged sword with respect to survival, depending on the method of administration and health status.

A family with type A insulin resistance syndrome caused by a novel insulin receptor mutation

Summary

A 17-year-old boy was referred to our endocrinology clinic for a clinical investigation of hyperinsulinemia. An oral glucose tolerance test showed plasma glucose concentrations in the normal range. However, insulin concentrations were considerably elevated (0 min: 71 μU/mL; 60 min: 953 μU/mL), suggesting severe insulin resistance. An insulin tolerance test confirmed that he had insulin resistance. There was no apparent hormonal or metabolic cause, including obesity. The patient had no outward features of hyperinsulinemia, including acanthosis nigricans or hirsutism. However, his mother and grandfather also had hyperinsulinemia. Genetic testing showed that the patient (proband), his mother, and his grandfather had a novel p.Val1086del heterozygous mutation in exon 17 of the insulin receptor gene (INSR). Although all three family members have the same mutation, their clinical courses have been different. The onset of the mother's diabetes was estimated at 50 years, whereas the grandfather developed diabetes at 77 years.

Learning points

Type A insulin resistance syndrome is caused by mutations in the insulin receptor (INSR) gene and results in severe insulin resistance. Genetic evaluation should be considered in adolescents or young adults with dysglycemia when an atypical phenotype, such as severe insulin resistance, or a relevant family history is observed. Clinical courses may differ even if the same genetic mutation is found in a family.

Bilateral non-traumatic elbow luxation in a Yorkshire terrier puppy

A 10-week-old Yorkshire terrier had lameness of the right forelimb with complete lateral radioulnar luxation at the humerus, consistent with Type III congenital elbow luxation; this is rarely treated in the presence of multiple skeletal deformities. Lateral subluxation of the radial head at the left elbow was diagnosed as Type I congenital elbow luxation. Procurvatum, distal valgus, and external torsion were present in both antebrachiae. Surgical stabilization of the right elbow was performed with temporary transarticular pins in the humeroulnar and radioulnar joints. A custom-made orthosis was applied to support the surgical reduction for 20 wk. Recurrent luxation was not observed. After complete right-sided function was established, the left forelimb showed noticeable instability in the antebrachium, and the puppy frequently fell while running. The lateral collateral ligament of the left elbow was augmented using screws and synthetic ligaments 22 wk after the right-side surgery. Congruity of the left elbow joint improved, and the puppy could bear full weight on the left forelimb, although slight deficits in movement and falling were observed. We demonstrate the effectiveness of combining a temporary transarticular pin and custom-made orthosis while treating Type III congenital elbow luxation and the inadequacy of collateral ligament augmentation alone for treating Type I congenital elbow luxation with antebrachium deformities. Key clinical message: Herein, we observed that a combination of a temporary transarticular pin and a custom-made orthosis was effective for the treatment of Type III congenital elbow luxations.

A Rare Case of Paratesticular Cystadenoma with Ovarian Stroma Found by Scrotal Ultrasound on a Cirrhotic Patient with Elevated Alpha-fetoprotein

Introduction/Objective

Paratesticular cystadenoma with ovarian stroma is a rare benign cyst-forming neoplasm with less than 10 cases reported in the literature. Typically, it presents in men aged 11 to 68 years (average 30) and is asymptomatic. The tumor is hypothesized to represent the efferent ductulus undergoing metaplastic change, the vestigial remnants of Mullerian duct, or mesothelium of the tunica vaginalis. Most tumors are considered benign, but a few cases of malignant transformation have been reported.

Methods/Case Report

We present a case of a 54-year-old male with a history of cirrhosis and elevated alpha-fetoprotein (17.85 ng/ML) who was found to have a paratesticular mass by scrotal ultrasound. Clinical history was obtained from review of electronic medical record. CD10 (Novocastra Clone 56C6) and progesterone receptor (PR) (Leica Clone 16) Immunoperoxidase stains were performed following the vendor recommendations. Surgical excision revealed a 0.6-cm polypoid nodule on tunica albuginea that was entirely submitted. Microscopically, the tumor was comprised of cystic spaces lined by cuboidal epithelium identical to that of the Fallopian tubes. There was a sparse spindle-shaped stroma underlying the epithelium similar to ovarian stroma. No nuclear atypia or mitosis was found. Immunoperoxidase stains showed the epithelium was positive for PR, and the stroma was positive for CD10. No evidence of germ cell tumor was identified.

Results (if a Case Study enter NA)

NA.

Conclusion

Characteristic histologic and immunophenotypic findings can aid in the diagnosis of paratesticular cystadenoma with ovarian stroma. Surgical resection for histological confirmation and long-term monitoring for the potential recurrence and metastatic spread are required.

Update of the fracture risk prediction tool FRAX: a systematic review of potential cohorts and analysis plan

We describe the collection of cohorts together with the analysis plan for an update of the fracture risk prediction tool FRAX with respect to current and novel risk factors. The resource comprises 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures.

INTRODUCTION

The availability of the fracture risk assessment tool FRAX® has substantially enhanced the targeting of treatment to those at high risk of fracture with FRAX now incorporated into more than 100 clinical osteoporosis guidelines worldwide. The aim of this study is to determine whether the current algorithms can be further optimised with respect to current and novel risk factors.

METHODS

A computerised literature search was performed in PubMed from inception until May 17, 2019, to identify eligible cohorts for updating the FRAX coefficients. Additionally, we searched the abstracts of conference proceedings of the American Society for Bone and Mineral Research, European Calcified Tissue Society and World Congress of Osteoporosis. Prospective cohort studies with data on baseline clinical risk factors and incident fractures were eligible.

RESULTS

Of the 836 records retrieved, 53 were selected for full-text assessment after screening on title and abstract. Twelve cohorts were deemed eligible and of these, 4 novel cohorts were identified. These cohorts, together with 60 previously identified cohorts, will provide the resource for constructing an updated version of FRAX comprising 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures. For each known and candidate risk factor, multivariate hazard functions for hip fracture, major osteoporotic fracture and death will be tested using extended Poisson regression. Sex- and/or ethnicity-specific differences in the weights of the risk factors will be investigated. After meta-analyses of the cohort-specific beta coefficients for each risk factor, models comprising 10-year probability of hip and major osteoporotic fracture, with or without femoral neck bone mineral density, will be computed.

CONCLUSIONS

These assembled cohorts and described models will provide the framework for an updated FRAX tool enabling enhanced assessment of fracture risk (PROSPERO (CRD42021227266)).

Multiple encephalopathy syndrome: a case of a novel radiological subtype of acute encephalopathy in childhood

INTRODUCTION

This report presents the case of a novel subtype of acute encephalopathy syndrome in childhood found in a patient with influenza type A infection; the patient exhibited evident magnetic resonance imaging (MRI) findings.

CASE REPORT

A 4-year-old boy was transferred to our hospital for prolonged (lasting 60 min) status epilepticus with influenza encephalopathy. Mild brain hypothermia therapy was applied for 72 h, followed by targeted temperature management for 96 h with mechanical ventilation in the intensive care unit. Moreover, methylprednisolone pulse therapy and immunoglobulin therapy were administered. One month after the treatment, his physical status recovered such that he was able to run, take food orally, communicate verbally, and successfully return to kindergarten. Interestingly, serial MRI studies revealed findings that were compatible with 1) acute necrotizing encephalopathy (ANE), 2) mild encephalitis/encephalopathy with a reversible splenial lesion (MERS type II), 3) acute cerebellitis, and 4) acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) on days 2, 4, 7, and 16, respectively.

CONCLUSIONS

To the best of our knowledge, these significant MRI findings associated with acute encephalopathy have never been reported. Thus, herein, we propose the new term radiological "multiple encephalopathy syndrome (MES)" based on our case of acute encephalopathy in childhood.

Force plate analysis of ground reaction forces in relation to gait velocity of healthy Beagles

OBJECTIVE

To evaluate changes in ground reaction forces (GRFs) in relation to gait velocity using 2 force plates (FPs) for healthy Beagles.

ANIMALS

18 healthy Beagles were included (body weight, 10.45 ± 1.28 kg; age, 26 ± 11 months).

PROCEDURES

Ten GRF parameters were measured at three gait velocities (walk, 0.9 to 1.2 m/s; trot 1, 1.6 to 2.0 m/s; and trot 2, 2.1 to 2.5 m/s): peak lateral force (PLF), peak medial force (PMF), lateral impulse (LI), medial impulse (MI), peak propulsive force (PPF), peak braking force (PBF), propulsive impulse (PI), braking impulse (BI), peak vertical force (PVF), and vertical impulse (VI).

RESULTS

As velocity increased, the PVF of all limbs increased, the VI of all limbs decreased, and the PPF of the forelimbs increased. At all velocities, PBF and BI were significantly higher than the PPF and PI in forelimbs; however, PBF and BI were significantly lower than the PPF and PI in hindlimbs. There were no significant differences in the PLF, PMF, LI, and MI of the forelimbs and hindlimbs among all velocities. The PLF was significantly higher than the PMF of forelimbs during trot 1 and trot 2.

CLINICAL RELEVANCE

These results may be useful when comparing healthy Beagles with diseased ones when premorbid data are not available. Because the forelimbs are mainly responsible for the braking force, it is suggested that weight bearing is more stable in the forelimbs than in the hindlimbs, which are mainly responsible for the propulsive force, and that a greater force is generated laterally than medially during trot.

Metabolic changes induced by dapagliflozin, an SGLT2 inhibitor, in Japanese patients with type 2 diabetes treated by oral anti-diabetic agents: A randomized, clinical trial

AIM

We aimed to determine whether SGLT2 inhibitor dapagliflozin treatment affects body composition and amino acid (AA) metabolism.

METHODS

Fifty-two overweight patients treated by oral antidiabetic agents were randomly assigned to dapagliflozin (Dapa) or a standard treatment (Con) and followed for 24 weeks. The primary outcome was the change in body mass (BM) between baseline and week 24. Body composition, intrahepatic triglyceride (IHTG) content, and plasma AA concentrations were examined as secondary outcomes.

RESULTS

The change in BM was significantly larger in the Dapa than in the Con group, with a difference in the mean change of -1.72 kg (95 %CI: -2.85, -0.59; P = 0.004) between the groups. Total fat mass was reduced by dapagliflozin treatment, but fat-free mass was maintained. IHTG content was significantly reduced in the Dapa than in the Con (P = 0.033). Changes in AAs showed small differences between the groups, but only serine concentrations were significantly reduced in the Dapa. Intra-group analysis showed that positive associations were observed between changes in branched chain AA concentrations and body composition only in the Dapa.

CONCLUSIONS

Dapagliflozin treatment causes a reduction in BM mainly by reducing fat mass. AA metabolism shows subtle changes with dapagliflozin treatment.

Molluscum contagiosum of the corneal limbus in an AIDS patient: a clinicopathological case report

Background

Molluscum contagiosum, a pox virus infection, is likely to occur in the eyelid skin; however, corneal involvements by molluscum lesions are extremely rare. We report a case of molluscum contagiosum arising in the corneal limbus in an untreated AIDS patient, together with anterior segment optical coherence tomography (OCT) findings and histopathology of the excised tumor.

Case presentation

A 46-year-old man with AIDS was referred to our department for the management of an ocular lesion. Blood tests revealed an extremely low CD4+ T-cell count of 11 cells/μL, being strongly positive for anti-HIV antibody (591.36 S/CO) with a high copy number of HIV RNA (8070.0 × 100 copy/mL). Slit-lamp examination of his right eye showed a white nodule at the lower limbus. Anterior segment OCT findings of the nodule revealed a highly reflective elevated lesion, which was considered to involve the Bowman layer. The nodular lesion was excised from the limbus including the superficial corneal stroma, and then processed for histologic examination. Histopathology of the excised lesion showed acanthotic corneal epithelium containing swollen cells with eosinophilic inclusions known as molluscum bodies. He was diagnosed with molluscum contagiosum.

Conclusions

Anterior segment OCT findings provide useful information for morphological evaluations of and preoperative strategies against molluscum contagiosum.

Glycaemia and body weight are regulated by sodium-glucose cotransporter 1 (SGLT1) expression via O-GlcNAcylation in the intestine

Objective

Methods

Results

Conclusion

•

Intestine-specific OGT depletion results in weight loss and hypoglycaemia.

•

It reduces SGLT1 expression, resulting in glucose absorption from the gut.

•

OGT knockdown may contribute to diminish glucose-induced incretin secretion.

•

OGT may regulate SGLT1 expression via the cAMP/CREB-dependent pathway.

•

O-GlcNAcylation regulates SGLT1 expression in the intestine and the kidney.

Determining the Variation in the Tibial Tuberosity Transposition Distance that is Required to Correct the Quadriceps Angle with the Severity of Medial Patellar Luxation of the Canine Stifle Joint

The aim of this study was to evaluate the transposition distance in in vitro canine medial patellar luxation (MPL) models of different severity grades using a single radiograph of the stifle joint. Each MPL grade model was generated with manipulation and evaluated by palpating the stability of the patella. An anterior-posterior radiograph of the entire hind limb with extended hip and stifle joints, including the iliopubic eminence, was used for all measurements. The quadriceps angles and the percentage of the transposition distance to the maximum width of the proximal tibia were measured. Our results demonstrated that when the tibial tuberosity transposition procedure is performed in a clinical setting, the required distance to correct the abnormal direction of the extensor mechanism in the canine stifle joint was greater in severe grade MPL than in mild grade MPL.

Diagnostic value of simultaneous 99mTc-sestamibi/123I-BMIPP imaging parameters for predicting the improvement of left ventricular wall motion after acute myocardial infarction using CZT SPECT system

Background

Although the presence of 99mTc-sestamibi/123I-BMIPP-mismatch, the reverse redistribution (RR) of 99mTc-sestamibi and RR of 123I-BMIPP in patients with acute myocardial infarction (AMI) are known to significant markers for predicting the improvement of LV wall motion in the infarcted territory in chronic phase, few studies were performed to analyze them by simultaneous dual-isotope imaging using cadmium-zinc-telluride (CZT) SPECT system.

Purpose

The purpose of this study was to evaluate whether the presence of 99mTc-sestamibi/123I-BMIPP-mismatch or RR of 99mTc-sestamibi, RR of 123I-BMIPP make better prediction of the improvement of LV wall motion in the infarcted territory.

Methods

We evaluated 42 consecutive patients with AMI who had undergone both dual-isotope SPECT in acute phase and stress myocardial SPECT using 99mTc-tracers in chronic phase by Discovery NM530c. The presence of 99mTc-sestamibi/123I-BMIPP-mismatch, RR of 99mTc-sestamibi and RR of 123I-BMIPP were determined using traditional definition. The improvement of LV wall motion in the infarcted territory from acute phase to chronic phase was assessed using QGS.

Results

Of 42 patients, the improvement of LV wall motion in the infarcted territory from acute phase to chronic phase was found in 29 patients. The presence of 99mTc-sestamibi/123I-BMIPP-mismatch and RR of 99mTc-sestamibi and RR of 123I-BMIPP were significantly linked to predict the improvement of LV wall motion (p=0.0001, p=0.0001 and p=0.002, respectively). To predict the improvement of LV wall motion in the infarcted territory in chronic phase, the presence of 99mTc-sestamibi/123I-BMIPP-mismatch showed sensitivity of 93%, specificity of 85% and accuracy of 91%, while RR of 99mTc-sestamibi and RR of 123I-BMIPP had sensitivities of 72%, 48%, specificities of 85%, 100% and accuracies of 76%, 64%, respectively. The multivariate discriminant analysis revealed that the combination of 99mTc-sestamibi/123I-BMIPP-mismatch, RR of 99mTc-sestamibi and RR of 123I-BMIPP best predicted the improvement of LV wall motion in the infarcted territory in chronic phase with sensitivity of 93%, specificity of 85% and accuracy of 91% (chi-square=40.6), compared with RR of 99mTc-sestamibi and RR of 123I-BMIPP only (sensitivity 79%, specificity 85% and accuracy of 81%, chi-square=16.9).

Conclusions

The addition of 99mTc-sestamibi/123I-BMIPP-mismatch on RR of 99mTc-sestamibi and RR of 123I-BMIPP in patients with AMI, help better predict the improvement of LV wall motion in the infarcted territory in chronic phase.

Funding Acknowledgement

Type of funding sources: None.

Intracellular localization of AMP deaminase and its novel role in BCAA and lipid metabolism in diabetic cardiomyopathy

Background

A metabolomic study in the human heart suggested a pivotal role of amino acid (AA) metabolism in fatty acid oxidation, which is dysregulated in type 2 diabetes mellitus (T2DM) and heart failure. We previously reported that aberrant up-regulation of AMP deaminase 3 (AMPD3) impairs cardiac energetics in T2DM hearts, and AMPD3 was recently shown to be activated by fasting and to promote AA metabolism and fatty acid oxidation in skeletal muscle. A sodium glucose cotransporter 2 inhibitor (SGLT2i) has been shown to augment systemic AA metabolism, but its effect on cardiac AA metabolism remains unknown.

Purpose

We hypothesized that AMPD3 has a role in AA and lipid metabolism in cardiomyocytes and that the protective effect of an SGLT2i in diabetic hearts is mediated by modification of AA and lipid metabolism.

Methods and results

Proteomic analyses of AMPD3 immunoprecipitates in rat hearts revealed that AMPD3 interacted with the E1α and E2 components of the BCKDH complex, a rate-limiting enzyme of branched-chain AA (BCAA) catabolism. Immunoblotting using subcellular fractions revealed that BCKDH localized not only in the mitochondria matrix but also in the cytosol and endoplasmic reticulum (ER) and that AMPD3 interacted with BCKDH in the cytosol and ER. Despite comparable expression of BCKDH components and phosphorylation of E1α at Ser293, significant accumulation of BCAA was observed in T2DM rats (OLETF; 317±30 nmol/g) compared to that in control rats (LETO; 213±16 nmol/g), and the accumulation of BCAA was accompanied by up-regulation of AMPD3 in the cytosol and ER by 98% and 231%, respectively. In cardiomyocytes, disruption of BCAA catabolism by knockdown of BCKDH-E1α resulted in a 5.8-fold increase in AMPD3 at the transcriptional level and blunted lipid droplet biogenesis in response to a long-chain fatty acid challenge. Next, myocardial infarction (MI) was induced in LETO and OLETF pretreated with empagliflozin (10 mg/kg/day, 14 days) or a vehicle. Pathway analysis of cardiac metabolites revealed arginine biosynthesis and BCAA metabolism as the most significantly changed pathways with empagliflozin, with BCAA (791±187 nmol/g), glutamate, glutamine and urea being significantly increased. Empagliflozin restored myocardial ATP and survival after MI in OLETF to levels comparable to those in LETO. Electron microscopy showed a significantly higher prevalence of myocardium lipid droplets in OLETF, which was further increased by empagliflozin.

Conclusions

The results support the hypotheses that imbalance of extra-mitochondrial AMPD3-BCKDH interaction underlies dysregulated BCAA metabolism in T2DM hearts and that activation of cardiac AA metabolism by an SGLT2i normalizes fatty acid overload through sequestration into intracellular lipid droplets.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Boehringer Ingelheim

Determination of the insertion position of implants for the cross-pin fixation of distal femoral physis fractures

The cross-pin technique for the treatment of distal femoral physis fractures (specifically, Salter-Harris Type I fractures) was investigated using femurs collected from beagle cadavers. The pin was inserted from the medial surface of the femur at an inclination of approximately 30 to 45° relative to the long axis of the femur in the anteroposterior direction; the pin exit was set proximal to the origin of the long digital extensor tendon. Digital and radiographic images of the femur in the anteroposterior and lateral directions were obtained. In both types of images, the insertion angle of the pin relative to the long axis was measured. Results suggest that when inserting a pin proximal to the fracture line, the ideal position can be achieved by inclining the pin approximately 20° cranially relative to the long axis of the lateral direction of the femur, in addition to the previously described criteria.

OS05.8.A A Phase 0/1 ‘Trigger’ Trial of Ribociclib Plus Everolimus in Recurrent High-Grade Glioma

BACKGROUND

The RB-CDK4/6 and mTOR signaling pathways are deregulated in high-grade glioma (HGG) and mTOR activation is a potential mechanism of resistance to CDK4/6 inhibition. This study evaluates the tumor pharmacokinetics (PK) and tumor pharmacodynamics (PD) of combined CDK4/6 and mTOR inhibition in recurrent HGG patients.

MATERIAL AND METHODS

Eligible patients had recurrent HGG with (1) intact RB expression, (2) CDKN2A/B deletion or CDK4/6 amplification, and (3) PTEN loss or PIK3CA mutations. Six patients received five days of presurgical ribociclib (400mg QD) plus everolimus (2.5mg QD) and then underwent tumor resection at 2, 8 or 24 hours following the last dose. Five subsequent dose-escalation cohorts each enrolled three additional patients, reaching a maximum dose-level of ribociclib (600mg QD) plus everolimus (60mg QW). Tumor tissue (gadolinium [Gd]-enhancing and nonenhancing regions), CSF, and plasma were collected. Total and unbound drug concentrations were determined using validated LC-MS/MS methods. Tumor PD effects, including RB and S6 phosphorylation, were compared to matched archival tissue. A PK ‘trigger’ (i.e., unbound concentration &gt; 5-fold biochemical IC50) and a PD ‘trigger’ (&gt;30% decrease in both pRB and pS6) were set for each drug. Gd-nonenhancing tissue exhibiting both PK and PD effects in excess of these thresholds qualified patients for postoperative combination therapy.

RESULTS

21 patients with WHO Grade III (n=2) and WHO Grade IV (n=19) gliomas were enrolled. No dose-limiting toxicities were observed. Following presurgical drug, all patients demonstrated marked decrease in Gd-enhancement on preoperative MRI. In Gd-nonenhancing tumor regions, the median unbound concentration of ribociclib was 719 nM (i.e., &gt; 5-fold biochemical IC50 for CDK4/6 inhibition), whereas the unbound everolimus tumor concentrations in all patients were below the lower limit of quantitation (i.e., &lt; 0.2 nM). The median total concentrations of everolimus in tumors at dose-levels 0 to 5 were 2.9, 8.8, 10.3, 5.0, 15.7, and 13.7 nM, respectively. Across all dose-levels, 62% (13/21) and 22% (5/21) of tumors demonstrated decreased tumor RB and S6 phosphorylation, respectively. Tumor proliferation (MIB-1) was decreased in 67% (14/21) of all patients.

CONCLUSION

In adult HGG, ribociclib achieves pharmacologically-relevant concentrations in Gd-nonenhancing tumor, consistent with the observed tumor PD effects. Everolimus exhibits very limited penetration into human glioma tissue. Our study supports further development of ribociclib, but not everolimus, for the treatment of glioma patients.

Mechanisms of instantaneous inactivation of SARS-CoV-2 by silicon nitride bioceramic

The hydrolytic processes occurring at the surface of silicon nitride (Si3N4) bioceramic have been indicated as a powerful pathway to instantaneous inactivation of SARS-CoV-2 virus. However, the virus inactivation mechanisms promoted by Si3N4 remain yet to be elucidated. In this study, we provide evidence of the instantaneous damage incurred on the SARS-CoV-2 virus upon contact with Si3N4. We also emphasize the safety characteristics of Si3N4 for mammalian cells. Contact between the virions and micrometric Si3N4 particles immediately targeted a variety of viral molecules by inducing post-translational oxidative modifications of S-containing amino acids, nitration of the tyrosine residue in the spike receptor binding domain, and oxidation of RNA purines to form formamidopyrimidine. This structural damage in turn led to a reshuffling of the protein secondary structure. These clear fingerprints of viral structure modifications were linked to inhibition of viral functionality and infectivity. This study validates the notion that Si3N4 bioceramic is a safe and effective antiviral compound; and a primary antiviral candidate to replace the toxic and allergenic compounds presently used in contact with the human body and in long-term environmental sanitation.

Cribriform carcinoma in the lymph nodes is associated with distant metastasis, recurrence, and survival among patients with node-positive colorectal cancer

Cribriform lymph node pattern is an independent risk factor for metachronous or synchronous distant metastasis in patients with stage III and IV node-positive colorectal cancer. Multivariable analysis in patients with stage III disease indicated that the cribriform pattern of carcinoma in the lymph nodes was an independent risk factor for recurrence and survival. Kaplan–Meier analysis demonstrated that the group with stage III cribriform-type lymph node carcinoma had shorter recurrence-free and overall survival times than the stage III group with the tubular type (P &lt; 0.001).

An infantile late-onset case Group of B Streptococcus meningitis diagnosed with a rapid latex kit

Globally, vaccination has reduced the prevalence of meningitis caused by Streptococcus pneumoniae Neisseria meningitidis, and Haemophilus influenzae. However, neonatal Group B Streptococcus (GBS) meningitis continues to remain a problematic infection of the central nervous system. Here, we report a case of bacterial meningitis in a 34-day old male baby who presented with fever. A cerebrospinal fluid (CSF) test on the day of admission showed an increase in cell count with decreased glucose level. A rapid latex test of the CSF using a commercial kit diagnosed the causative pathogen as GBS. We administered the antibiotics ampicillin, cefotaxime, gentamicin and panipenem/betamipron to the patient for over 14 days. Partial seizures were frequently observed during the course and were well-controlled with midazolam and phenobarbital. Brain magnetic resonance imaging on day 17 showed subdural hygroma in the frontal region, and 99mTc ethyl-cysteinate dimer-single photon emission computed tomography confirmed a decreased cerebral blood flow predominantly in the left frontal region. After three years of follow-up, the condition of the patient improved without any neurological sequelae. Our report highlights that rapid identification of the causative organism is essential in infantile late-onset meningitis. In addition, we consider that the latex kit-based rapid testing of CSF is beneficial for identifying the causative agent of bacterial meningitis.

Establishment of novel specific assay for short-form glucose-dependent insulinotropic polypeptide and evaluation of its secretion in nondiabetic subjects

The short‐form glucose‐dependent insulinotropic polypeptide (GIP) (1–30) is released from islet alpha cells and promotes insulin secretion in a paracrine manner in vitro. However, it is not well elucidated how GIP (1–30) is involved in glucose metabolism in vivo, since a specific assay system for GIP (1–30) has not yet been established. We first developed a sandwich enzyme‐linked immunosorbent assay (ELISA) specific for GIP (1–30) by combining a novel antibody specific to the GIP (1–30) C terminus with the common antibody against GIP N terminus. Then, we explored cross‐reactivities with incretins and glucagon‐related peptides in this ELISA. GIP (1–30) amide, but not GIP (1–42), GLP‐1, or glucagon increased absorbance in a dose‐dependent manner. We next measured plasma GIP (1–30) concentrations in nondiabetic participants (ND) during a 75‐g oral glucose tolerance test or cookie meal test (carbohydrates 75 g, lipids 28.5 g, proteins 8.5 g). Both glucose and cookie load increased GIP (1–30) concentrations in ND, but the increases were much lower than those of GIP (1–42). Furthermore, the DPP‐4 inhibitor significantly increased GIP (1–30) concentrations similarly to GIP (1–42) in ND. In conclusion, we for the first time developed an ELISA specific for GIP (1–30) and revealed its secretion in ND.

Investigation of the effects of excessive tibial plateau angle and changes in load on ligament tensile forces in the stifle joints of dogs

OBJECTIVE

To investigate the effect of an excessive tibial plateau angle (TPA) and change in compressive load on tensile forces experienced by the cranial cruciate, medial collateral, and lateral collateral ligaments (CCL, MCL, and LCL, respectively) of canine stifle joints.

SAMPLE

16 cadaveric stifle joints from 16 orthopedically normal Beagles.

PROCEDURES

Stifle joints were categorized into unchanged (mean TPA, 30.4°) and excessive (mean TPA before and after modification, 31.2° and 41.1°, respectively) TPA groups. The excessive TPA group underwent a TPA-increasing procedure (curvilinear osteotomy of the proximal aspect of the tibia) to achieve the desired TPA. A robotic system was used to apply a 30- and 60-N compressive load to specimens. The craniomedial band of the CCL, caudolateral band of the CCL, MCL, and LCL were sequentially transected; load application was repeated after each transection. Orthogonal force components were measured in situ. Forces on ligaments were calculated after repeated output force measurements as the contribution of each component was eliminated.

RESULTS

Increasing the compressive load increased tensile forces on the craniomedial and caudolateral bands of the CCL, but not on the MCL or LCL, in specimens of both groups. At the 60-N load, tensile force on the craniomedial band, but not other ligaments, was greater for the excessive TPA group than for the unchanged TPA group.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that stress on the CCL may increase when the compressive load increases. The TPA-increasing procedure resulted in increased tensile force on the CCL at a 60-N compressive load without affecting forces on the MCL or LCL.

Acromegaly Cases Exhibiting Increased Growth Hormone Levels during Oral Glucose Loading with Preadministration of Dipeptidyl Peptidase-4 Inhibitor

Objective Glucose-dependent insulinotropic polypeptide (GIP) is speculated to worsen growth hormone (GH) hypersecretion in acromegaly and to be a cause of paradoxical increases in GH (PI-GH) during 75-g oral glucose tolerance testing (75-g OGTT). Dipeptidyl peptidase-4 inhibitors (DPP4is), which increase the circulating concentration of active GIP, are frequently administered to diabetic patients, including those with acromegaly. We aimed to determine whether or not the administration of a DPP4i increases GH concentration, especially in patients demonstrating PI-GH during a DPP4i-OGTT, in which a DPP4i was administered immediately before 75-g OGTT. Methods This prospective cross-sectional study was carried out on acromegalic patients admitted to Hokkaido University hospital between June 2011 and May 2018. The participants underwent both 75-g OGTT and DPP4i-OGTT. For those who underwent surgery, immunohistochemical staining and quantitative polymerase chain reaction (PCR) for the GIP receptor (GIPR) were performed on the resected pituitary adenomas. Results Twenty-five percent of the participants had PI-GH confirmed (3 of 12 cases). Two of the three participants who demonstrated PI-GH exhibited higher circulating GH concentrations during DPP4i-OGTT than during OGTT. The increase in plasma glucose was reduced during DPP4i-OGTT compared to during 75-g OGTT, suggesting that the increase in GH during DPP4i-OGTT was due not to high glucose concentrations but instead increased GIP caused by the administration of DPP4i. The adenoma from one participant with PI-GH displayed positive immunostaining for GIPR and a higher GIPR messenger ribonucleic acid (mRNA) expression than the others. Conclusion DPP4i may enhance the GH secretion response during glucose loading, especially in individuals with PI-GH.

Insulinoma induces a hyperinsulinemia-mediated decrease of GLUT2 and GLP1 receptor in normal pancreatic β-cells

There have been several clinical reports of transient postoperative hyperglycemia in patients with insulinoma, but the effect of insulinoma on normal β-cells has not been investigated. We examined the glucose transporter 2 (GLUT2) and glucagon-like peptide 1 receptor (GLP1R) expression in normal pancreatic β-cells of five patients with insulinoma and five patients with normal glucose tolerance (NGT) as controls. The positive rate of GLUT2-or GLP1R-positive islets in the nontumor area was calculated by the ratio with the analyzed islets. For functional in vitro analyses, q-PCR and Western blotting were performed after insulin loading on MIN6 cells. The expression rates of both GLUT2 and GLP1R were significantly lower in nontumor area islets of insulinoma patients than in patients with NGT (GLUT2: 31.6 ± 15.3% vs 95.9 ± 6.7%, p < 0.01, GLP1R: 66.8 ± 15.0% vs 96.7 ± 5.0%, p < 0.01). Exposure of MIN6 cells to high concentrations of insulin resulted in a significant decrease in GLUT2 protein for 12 h and GLP1R protein for 24 h (GLUT2; 1.00 ± 0.079 vs 0.81 ± 0.04. p = 0.02, GLP1R; 1.00 ± 0.10 vs 0.50 ± 0.24, p = 0.03) but not in those mRNAs. Our findings show that insulinoma is associated with the downregulation of GLUT2 and GLP1R expression in nontumor area islets. These phenomena may be caused by high levels of insulin.

Prediction of the improvement of left ventricular wall motion after acute myocardial infarction by simultaneous dual-isotope imaging with 99mTc-sestamibi/123I-BMIPP using cadmium-zinc-telluride SPECT

Background/Introduction

Although both the presence of 99mTc-sestamibi/123I-BMIPP mismatch and the reverse redistribution of 99mTc-sestamibi in patients with acute myocardial infarction (AMI) are known to significant markers for predicting the improvement of left ventricular (LV) wall motion in the infarcted territory in chronic phase, few studies evaluated them by simultaneous dual-isotope (99mTc-sestamibi/123I-BMIPP) imaging using cadmium-zinc-telluride (CZT) SPECT system.

Purpose

The purpose of this study was to evaluate whether the presence of 99mTc-sestamibi/123I-BMIPP mismatch or the reverse redistribution of 99mTc-sestamibi make better prediction of the improvement of LV wall motion in the infarcted territory.

Methods

We evaluated 30 consecutive patients with AMI who had undergone both dual-isotope (99mTc-sestamibi/123I-BMIPP) SPECT in acute phase and stress myocardial SPECT using 99mTc-tracers in chronic phase by Discovery NM530c. Both 99mTc-sestamibi/123I-BMIPP mismatch and reverse redistribution of 99mTc-sestamibi were determined using traditional definition. The improvement of LV wall motion in the infarcted territory from acute phase to chronic phase was assessed using QGS.

Results

Of 30 patients, the improvement of LV wall motion in the infarcted territory from acute phase to chronic phase was found in 20 patients. Both the presence of 99mTc-sestamibi/123I-BMIPP mismatch and reverse redistribution of 99mTc-sestamibi were significantly linked to predict the improvement of LV wall motion (p=0.0001, p=0.011, respectively). The respective sensitivities, specificities and accuracies in the prediction of the improvement of LV wall motion in the infarcted territory were 90%, 90% and 90% with 99mTc-sestamibi/123I-BMIPP mismatch, and 60%, 90%, 70% with reverse redistribution of 99mTc-sestamibi.

Conclusions

In the simultaneous 99mTc-sestamibi/123I-BMIPP dual-isotope imaging using CZT SPECT system, both the presence of 99mTc-sestamibi/123I-BMIPP mismatch and the reverse redistribution of 99mTc-sestamibi in acute phase are useful for predicting the improvement of LV wall motion in chronic phase, but the presence of 99mTc-sestamibi/123I-BMIPP mismatch is superior to the reverse redistribution of 99mTc-sestamibi for it.

Funding Acknowledgement

Type of funding source: None

Prediction of myocardial viability in chronic phase in patients with acute myocardial infarction by simultaneous dual-isotope imaging with 99mTc-sestamibi/123I-BMIPP SPECT using CZT camera system

Objectives

The objective of this study was to determine the optimal cut-off value of % uptake of simultaneous dual-isotope (99mTc-sestamibi/123I-BMIPP) SPECT in patients with acute myocardial infarction (AMI) for prediction of myocardial viability in chronic phase.

Methods

We evaluated 30 consecutive patients with AMI who had undergone both dual-SPECT in acute phase and stress myocardial SPECT using 99mTc-tracers in chronic phase by Discovery NM530c. Regional % uptake with a 17-segment model was obtained using QPS software. The presence of myocardial viability was defined when regional % uptake ≥50% in 99mTc SPECT at rest in chronic phase was observed. Receiver operating characteristic (ROC) curves were analyzed to determine the optimal cutoff values of regional % uptake in both left anterior descending artery (LAD) territory and non-LAD coronary territory in acute phase to predict the myocardial viability in chronic phase.

Results

The cutoff values for prediction of viable myocardium were %uptake ≥47% for 99mTc-sestamibi, %uptake ≥31% for 123I-BMIPP in acute phase in LAD territory and %uptake ≥52% for 99mTc-sestamibi, %uptake ≥48% for 123I-BMIPP in non-LAD territory. The respective sensitivities, specificities and the area under the ROC curve (AUC) values in the prediction of myocardial viability were 92%, 92% and 0.94 with 99mTc-sestamibi, 90%, 85%, 0.92 with 123I-BMIPP in LAD territory, and 81%, 93% and 0.92 with 99mTc-sestamibi, 81%, 90%, 0.92 with 123I-BMIPP in non-LAD territory. There were no significant differences in AUC values between 99mTc-sestamibi and 123I-BMIPP in both LAD territory and non-LAD coronary territory.

Conclusions

In the simultaneous 99mTc-sestamibi/123I-BMIPP dual-isotope imaging in patients with AMI, these results suggest that not only 99mTc-sestamibi SPECT, but also 123I-BMIPP SPECT may be possible to predict the presence of myocardial viability in chronic phase. But it should be noted that the optimal cutoff values of regional % uptake in acute phase to predict the myocardial viability may differ for LAD territory and non-LAD coronary territory.

Funding Acknowledgement

Type of funding source: None