Cardiac imaging and biomarkers for assessing myocardial fibrosis in children with hypertrophic cardiomyopathy

BACKGROUND

Myocardial fibrosis, as diagnosed on cardiac magnetic resonance imaging (cMRI) by late gadolinium enhancement (LGE), is associated with adverse outcomes in adults with hypertrophic cardiomyopathy (HCM), but its prevalence and magnitude in children with HCM have not been established. We investigated: (1) the prevalence and extent of myocardial fibrosis as detected by LGE cMRI; (2) the agreement between echocardiographic and cMRI measurements of cardiac structure; and (3) whether serum concentrations of N-terminal pro hormone B-type natriuretic peptide (NT-proBNP) and cardiac troponin-T are associated with cMRI measurements.

METHODS

A cross-section of children with HCM from 9 tertiary-care pediatric heart centers in the U.S. and Canada were enrolled in this prospective NHLBI study of cardiac biomarkers in pediatric cardiomyopathy (ClinicalTrials.gov Identifier: NCT01873976). The median age of the 67 participants was 13.8 years (range 1-18 years). Core laboratories analyzed echocardiographic and cMRI measurements, and serum biomarker concentrations.

RESULTS

In 52 children with non-obstructive HCM undergoing cMRI, overall low levels of myocardial fibrosis with LGE >2% of left ventricular (LV) mass were detected in 37 (71%) (median %LGE, 9.0%; IQR: 6.0%, 13.0%; range, 0% to 57%). Echocardiographic and cMRI measurements of LV dimensions, LV mass, and interventricular septal thickness showed good agreement using the Bland-Altman method. NT-proBNP concentrations were strongly and positively associated with LV mass and interventricular septal thickness (P < .001), but not LGE.

CONCLUSIONS

Low levels of myocardial fibrosis are common in pediatric patients with HCM seen at referral centers. Longitudinal studies of myocardial fibrosis and serum biomarkers are warranted to determine their predictive value for adverse outcomes in pediatric patients with HCM.

Extracorporeal photopheresis to attenuate decline in lung function due to refractory obstructive allograft dysfunction

BACKGROUND

This study was designed to prospectively evaluate the efficacy of extracorporeal photopheresis (ECP) to attenuate the rate of decline of FEV₁ in lung transplant recipients with refractory bronchiolitis obliterans. Due to an observed higher than expected early mortality, a preliminary analysis was performed.

STUDY DESIGN AND METHODS

Subjects from 10 lung transplant centres were assigned to ECP treatment or to observation based on spirometric criteria, with potential crossover for those under observation. The primary endpoint of this study was to assess response to ECP (i.e., greater than a 50% decrease in the rate of FEV₁ decline) before and 6 months after initiation of ECP. Mortality was also evaluated 6 and 12 months after enrolment as a secondary endpoint.

RESULTS

Of 44 enrolled subjects, 31 were assigned to ECP treatment while 13 were initially assigned to observation on a non-random basis using specific spirometric inclusion criteria (seven of the observation patients subsequently crossed over to receive ECP). Of evaluable patients, 95% of patients initially assigned to treatment responded to ECP with rates of FEV₁ decline that were reduced by 93% in evaluable ECP-treated patients. Mortality rates (percentages) at 6 and 12 months after enrolment was 32% and 41%, respectively. The most common (92%) primary cause of death was respiratory or graft failure. Significantly (p = 0.002) higher rates of FEV₁ decline were observed in the non-survivors (-212 ± 177 ml/month) when compared to the survivors (-95 ± 117 ml/month) 12 months after enrolment. In addition, 18 patients with bronchiolitis obliterans syndrome (BOS) diagnosis within 6 months of enrolment had lost 38% of their baseline lung function at BOS diagnosis and 50% of their lung function at enrolment.

CONCLUSIONS

These analyses suggest that earlier detection and treatment of BOS should be considered to appreciate improved outcomes with ECP.

The efficacy of extracorporeal photopheresis to arrest bronchiolitis obliterans in lung allograft recipients was compared between two automated photopheresis instruments

BACKGROUND

The most common instruments used for extracorporeal photopheresis (ECP) treatment in the United States are the UVAR XTS and the CELLEX devices (Therakos, West Chester, PA). When compared to the UVAR XTS instrument, the efficacy of the CELLEX instrument to arrest the decline in lung function in patients with chronic lung allograft dysfunction (CLAD) related to bronchiolitis obliterans (BOS) has not been previously evaluated.

METHODS

The relative efficacy of the CELLEX vs UVAR XTS ECP instruments was assessed by comparing the difference in rates of FEV₁ decline before and after ECP treatment and survival in two series of lung allograft recipients with BOS who had been treated with these instruments.

RESULTS

Similar Slope Difference values for change in rate of decline (6 months Post ECP - Pre ECP) were observed between the two cohorts (UVAR XTS: 85 ± 109 mL/month vs CELLEX: 76 ± 128 mL/month, p=0.72). A similar percentage of patients responded to ECP (UVAR XTS: 77% vs CELLEX: 89%; p=0.36) i.e., as defined as a positive difference in slope between the rate of decline of FEV₁ before and 6 months after ECP. Survival at either 6 (p=0.89) or 12 (p=0.8) months after the start of ECP was not associated with instrument used despite a trend in higher early mortality (34% vs 17%, p=0.054) in the patients who were predominately treated with the CELLEX.

CONCLUSIONS

Our data support the use of the CELLEX for prospective studies designed to evaluate the merits of ECP in this population.

Acquired midfoot deformity and function in individuals with diabetes and peripheral neuropathy

BACKGROUND

Diabetes mellitus related medial column foot deformity is a major contributor to ulceration and amputation. However, little is known about the relationship between medial column alignment and function and the integrity of the soft tissues that support and move the medial column. The purposes of this study were to determine the predictors of medial column alignment and function in people with diabetes and peripheral neuropathy.

METHODS

23 participants with diabetes and neuropathy had radiographs, heel rise kinematics, magnetic resonance imaging and isokinetic muscle testing to measure: 1) medial column alignment (Meary's angle--the angle between the 1st metatarsal longitudinal axis and the talar head and neck), 2) medial column function (forefoot relative to hindfoot plantarflexion during heel rise), 3) intrinsic foot muscle and fat volume, ratio of posterior tibialis to flexor digitorum tendon volume, 4) plantar fascia function (Meary's angle change from toes flat to extended) and 5) plantarflexor peak torque. Predictors of medial column alignment and function were determined using simultaneous entry multiple regression.

FINDINGS

Posterior tibialis to flexor digitorum tendon volume ratio and intrinsic foot muscle volume were significant predictors of medial column alignment (P<.05), accounting for 44% of the variance. Intrinsic foot fat volume and plantarflexor peak torque were significant predictors of medial column function (P<.05), accounting for 37% of the variance.

INTERPRETATION

Deterioration of medial column supporting structures predicted alignment and function. Prospective research is required to monitor alignment, structure, and function over time to inform early intervention strategies to prevent deformity, ulceration, and amputation.

TCIA: An information resource to enable open science

Reusable, publicly available data is a pillar of open science. The Cancer Imaging Archive (TCIA) is an open image archive service supporting cancer research. TCIA collects, de-identifies, curates and manages rich collections of oncology image data. Image data sets have been contributed by 28 institutions and additional image collections are underway. Since June of 2011, more than 2,000 users have registered to search and access data from this freely available resource. TCIA encourages and supports cancer-related open science communities by hosting and managing the image archive, providing project wiki space and searchable metadata repositories. The success of TCIA is measured by the number of active research projects it enables (>40) and the number of scientific publications and presentations that are produced using data from TCIA collections (39).

Improved surgical outcomes for breast cancer patients receiving neoadjuvant aromatase inhibitor therapy: results from a multicenter phase II trial

BACKGROUND

Neoadjuvant aromatase inhibitor therapy has been reported to improve surgical outcomes for postmenopausal women with clinical stage II or III hormone receptor-positive breast cancer. A multicenter phase II clinical trial was conducted to investigate the value of this approach for US surgical practice.

STUDY DESIGN

One hundred fifteen postmenopausal women with >2 cm, estrogen receptor (ER) or progesterone receptor (PgR)-positive breast cancer were enrolled in a trial of 16 to 24 weeks of letrozole 2.5 mg daily before operation.

RESULTS

One hundred six patients were eligible for primary analysis, 96 underwent operations, 7 received chemotherapy after progressive disease, and 3 did not undergo an operation. Baseline surgical status was marginal for breast-conserving surgery (BCS) in 48 (45%), 47 were definitely ineligible for BCS (44%), and 11 were inoperable by standard mastectomy (10%). Overall Response Evaluation Criteria In Solid Tumors clinical response rate in the breast was 62%, with 12% experiencing progressive disease. Fifty percent underwent BCS, including 30 of 46 (65%) patients who were initially marginal for BCS and 15 of 39 (38%) patients who were initially ineligible for BCS. All 11 inoperable patients successfully underwent operations, including 3 (27%) who had BCS. Nineteen percent of patients undergoing mastectomy had a pathologic T1 tumor, suggesting that some highly responsive tumors were overtreated surgically.

CONCLUSIONS

Neoadjuvant aromatase inhibitor improves operability and facilitates BCS, but there was considerable variability in responsiveness. Better techniques to predict response, determine residual tumor burden before operation, and greater willingness to attempt BCS in responsive patients could additionally improve the rate of successful BCS.

Anthropometric optical surface imaging system repeatability, precision, and validation

Disciplines using human body surface dimensions require accurate, repeatable measurements. This study presents a design for the analysis of repeatability, precision, and validation of a new anthropometric device. This model enables estimation of the proportion of the total variation attributable to each level of data collection. This model is applied to an analysis of repeatability, precision, and validation of the Cencit Imaging System, a new optical surface scanner. Twenty-seven facial landmarks were marked on 10 men and 10 women at two measurement sessions. Two images were scanned during each session, and each image was digitized twice. The Cencit Imaging System results were compared with a previously validated digitizer. The Cencit Imaging System was found to produce accurate, highly repeatable images. Much of the error in this study is attributable to human error in marking landmarks on the subjects. The new imaging system will prove useful in a variety of anthropometric applications.