Detection of metallic cobalt and chromium liver deposition following failed hip replacement using T2* and R2 magnetic resonance

BACKGROUND: Failed hip prostheses can cause elevated circulating cobalt and chromium levels, with rare reports of fatal systemic organ deposition, including cobalt cardiomyopathy. Although blood cobalt and chromium levels are easily measured, organ deposition is difficult to detect without invasive biopsy. The T2* magnetic resonance (MR) method is used to quantify tissue iron deposition, and plays an important role in the management of iron-loading conditions. Cobalt and chromium, like iron, also affect magnetism and are proposed MR contrast agents. CASE PRESENTATION: We describe a case of a 44-year-old male with a failed hip implant and very elevated blood cobalt and chromium levels. Despite normal cardiac MR findings, liver T2* and R2 values were abnormal, triggering tissue biopsy. Liver tissue analysis, including X-ray fluorescence, demonstrated heavy elemental cobalt and chromium deposition in macrophages, and no detectable iron. CONCLUSIONS: Our case demonstrates T2* and R2 quantification of liver metal deposition in a patient with a failed hip implant. Further work is needed to investigate the role of T2* and R2 MR in the detection of metal deposition from metal on metal hip prostheses

Intra-Ring Variations in Mature Douglas-Fir Trees From Provenance Plantations

Variations in seven intra-ring characteristics were studied in juvenile and mature wood from two Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] genetic plantations. Samples were collected from 30 families representing 10 provenances with two replicates in each plantation. The following characteristics were determined by X-ray densitometry: earlywood density (EWD), latewood density (LWD), average ring density (RD), earlywood width (EWW), latewood width (LWW), total ring width (RW), and latewood proportion (LWP). Variation patterns were analyzed by two models: (1) families pooled across provenances and (2) provenances and families-within-provenances.Differences between plantations were significant for all traits except juvenile RD and mature RW and EWD. Variance components associated with families (pooled across provenances) remained the same with stand development and were biased upwards as a result of provenance variation. Genetic variation resulting from provenances was evident for RD and EWD, but (except for LWP) was relatively unimportant for RW parameters. Selection for families within populations can contribute to juvenile RW, as well as to mature RD and LWP

Intra-Ring Variations in Mature Douglas-Fir Trees From Provenance Plantations

Variations in seven intra-ring characteristics were studied in juvenile and mature wood from two Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] genetic plantations. Samples were collected from 30 families representing 10 provenances with two replicates in each plantation. The following characteristics were determined by X-ray densitometry: earlywood density (EWD), latewood density (LWD), average ring density (RD), earlywood width (EWW), latewood width (LWW), total ring width (RW), and latewood proportion (LWP). Variation patterns were analyzed by two models: (1) families pooled across provenances and (2) provenances and families-within-provenances.Differences between plantations were significant for all traits except juvenile RD and mature RW and EWD. Variance components associated with families (pooled across provenances) remained the same with stand development and were biased upwards as a result of provenance variation. Genetic variation resulting from provenances was evident for RD and EWD, but (except for LWP) was relatively unimportant for RW parameters. Selection for families within populations can contribute to juvenile RW, as well as to mature RD and LWP

Recreational marathon running does not cause exercise-induced left ventricular hypertrabeculation.

BACKGROUND: Marathon running in novices represents a natural experiment of short-term cardiovascular remodeling in response to running training. We examine whether this stimulus can produce exercise-induced left ventricular (LV) trabeculation. METHODS: Sixty-eight novice marathon runners aged 29.5 ± 3.2 years had indices of LV trabeculation measured by echocardiography and cardiac magnetic resonance imaging 6 months before and 2 weeks after the 2016 London Marathon race, in a prospective longitudinal study. RESULTS: After 17 weeks unsupervised marathon training, indices of LV trabeculation were essentially unchanged. Despite satisfactory inter-observer agreement in most methods of trabeculation measurement, criteria defining abnormally hypertrabeculated cases were discordant with each other. LV hypertrabeculation was a frequent finding in young, healthy individuals with no subject demonstrating clear evidence of a cardiomyopathy. CONCLUSION: Training for a first marathon does not induce LV trabeculation. It remains unclear whether prolonged, high-dose exercise can create de novo trabeculation or expose concealed trabeculation. Applying cut off values from published LV noncompaction cardiomyopathy criteria to young, healthy individuals risks over-diagnosis

Noninvasive rapid cardiac magnetic resonance for the assessment of cardiomyopathies in low-middle income countries

INTRODUCTION: Cardiac Magnetic Resonance (CMR) is a crucial diagnostic imaging test that redefines diagnosis and enables targeted therapies, but the access to CMR is limited in low-middle Income Countries (LMICs) even though cardiovascular disease is an emergent primary cause of mortality in LMICs. New abbreviated CMR protocols can be less expensive, faster, whilst maintaining accuracy, potentially leading to a higher utilization in LMICs. AREAS COVERED: This article will review cardiovascular disease in LMICs and the current role of CMR in cardiac diagnosis and enable targeted therapy, discussing the main obstacles to prevent the adoption of CMR in LMICs. We will then review the potential utility of abbreviated, cost-effective CMR protocols to improve cardiac diagnosis and care, the clinical indications of the exam, current evidence and future directions. EXPERT OPINION: Rapid CMR protocols, provided that they are utilized in potentially high yield cases, could reduce cost and increase effectiveness. The adoption of these protocols, their integration into care pathways, and prioritizing key treatable diagnoses can potentially improve patient care. Several LMIC countries are now pioneering these approaches and the application of rapid CMR protocols appears to have a bright future if delivered effectively

Proposed Stages of Myocardial Phenotype Development in Fabry Disease

OBJECTIVES: The authors sought to explore the Fabry myocardium in relation to storage, age, sex, structure, function, electrocardiogram changes, blood biomarkers, and inflammation/fibrosis. BACKGROUND: Fabry disease (FD) is a rare, x-linked lysosomal storage disorder. Mortality is mainly cardiovascular with men exhibiting cardiac symptoms earlier than women. By cardiovascular magnetic resonance, native T1 is low in FD because of sphingolipid accumulation. METHODS: A prospective, observational study of 182 FD (167 adults, 15 children; mean age 42 ± 17 years, 37% male) who underwent cardiovascular magnetic resonance including native T1, late gadolinium enhancement (LGE), and extracellular volume fraction, 12-lead electrocardiogram, and blood biomarkers (troponin and N-terminal pro-brain natriuretic peptide). RESULTS: In children, T1 was never below the normal range, but was lower with age (9 ms/year, r = −0.78 children; r = −0.41 whole cohort; both p < 0.001). Over the whole cohort, the T1 reduction with age was greater and more marked in men (men: −1.9 ms/year, r = −0.51, p < 0.001; women: −1.4 ms/year, r = −0.47 women, p < 0.001). Left ventricular hypertrophy (LVH), LGE, and electrocardiogram abnormalities occur earlier in men. Once LVH occurs, T1 demonstrates major sex dimorphism: with increasing LVH in women, T1 and LVH become uncorrelated (r = −0.239, p = 0.196) but in men, the correlation reverses and T1 increases (toward normal) with LVH (r = 0.631, p < 0.001), a U-shaped relationship of T1 to indexed left ventricular mass in men. CONCLUSIONS: These data suggest that myocyte storage starts in childhood and accumulates faster in men before triggering 2 processes: a sex-independent scar/inflammation regional response (LGE) and, in men, apparent myocyte hypertrophy diluting the T1 lowering of sphingolipid

Extracellular volume with bolus-only technique in amyloidosis patients: Diagnostic accuracy, correlation with other clinical cardiac measures, and ability to track changes in amyloid load over time

BACKGROUND: Extracellular volume (ECV) by T1 mapping requires the contrast agent distribution to be at equilibrium. This can be achieved either definitively with a primed contrast infusion (infusion ECV), or sufficiently with a delay postbolus (bolus-only ECV). For large ECV, the bolus-only approach measures higher than the infusion ECV, causing some uncertainty in diseases such as amyloidosis. PURPOSE: To characterize the relationship between the bolus-only and current gold-standard infusion ECV in patients with amyloidosis. STUDY TYPE: Bolus-only and infusion ECV were prospectively measured. POPULATION: In all, 186 subjects with systemic amyloidosis attending our clinic and 23 subjects with systemic amyloidosis who were participating in an open-label, two-part, dose-escalation, phase 1 trial. FIELD STRENGTH: Avanto 1.5T, Siemens Medical Solutions, Erlangen, Germany. ASSESSMENT: Bolus-only and infusion ECV were measured in all subjects using shortened modified Look-Locker inversion recovery (ShMOLLI) T1 mapping sequence. STATISTICAL TESTS: Pearson correlation coefficient (r); Bland-Altman; receiver operating characteristic (ROC) curve analysis. Linear regression model with a fractional polynomial transformation. RESULTS: The difference between the bolus-only and infusion myocardial ECV increased as the average of the two measures increased, with the bolus-ECV measuring higher. For an average ECV of 0.4, the difference was 0.013. The 95% limits of agreement for the two methods, after adjustment for the bias, were ±0.056. However, cardiac diagnostic accuracy was comparable (bolus-only vs. infusion ECV area under the curve [AUC] = 0.839 vs. 0.836), as were correlations with other clinical cardiac measures, and, in the trial patients, the ability to track changes in the liver/spleen with therapy. DATA CONCLUSION: In amyloidosis, with large ECVs, the bolus-only technique reads higher than the infusion technique, but clinical performance by any measure is the same. Given the work-flow advantages, these data suggest that the bolus-only approach might be acceptable for amyloidosis, and might support its use as a surrogate endpoint in future clinical trials. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2017

An insight into the suspected HbA2' cases detected by high performance liquid chromatography in Pakistan

Background:Hemoglobin A2\u27 (delta 16 Gly Arg) is globally the commonest delta chain variant of HbA2. It is clinically and hematologically silent but its sole importance lies in the underestimation of HbA2 quantity during the workup of beta-thalassaemia trait. High performance liquid chromatography (HPLC) identifies it as a small S-window peak with a mean retention time of 4.59 0.03 minutes. This study aims at describing the frequency of detection of HbA2\u27 by HPLC in Pakistan and its confirmation at a molecular level. Potential HbA2\u27 cases were identified by a retrospective review of 10186 HPLC chromatograms in year 2006. Prospective samples were collected for polymerase chain reaction (PCR) amplification, restriction digestion and nucleotide sequencing. Findings: One hundred and ninety two potential cases (1.89%) of HbA2\u27 were detected on HPLC, having mean retention time of 4.59 0.05 minutes. Sixty four (0.6%) new cases were suspected of having co-existing beta-thalassaemia trait when the quantity of S-window peaks was taken into account. Thirteen samples with presumed HbA2\u27 on HPLC were subjected to molecular analysis and the said mutation (delta 16 GGC CGC) was not detected in any sample. Conclusion: It is concluded that diagnosis of HbA2\u27 on HPLC alone is not justified, as evidence of the presence of this delta chain variant in Pakistani population is yet to be proven. Such small S-window peaks should be either disregarded or confirmed at molecular level, and only then should influence the diagnosis of beta-thalassaemia trait. Further studies are required to determine the true nature of these peaks