Intraprosthetic dislocation of dual-mobility total hip arthroplasty implant.

Dual-mobility total hip arthroplasties were developed to decrease the risk of dislocation and instability seen with traditional fixed-bearing total hip arthroplasties. However, dual-mobility constructs, notably the first-generation design, come with a risk of intraprosthetic dislocation (IPD). These dislocations occur when the polyethylene femoral head component is dislodged, causing direct articulation between the inner ceramic femoral head and the metal acetabular shell. This is different than a polyethylene liner dislocation in a standard total hip arthroplasty. Causes of IPD include polyethylene wear and iatrogenic dislocation from closed reduction attempts. Timely identification is essential to reduce the risk of soft tissue metallosis, raised cobalt and chromium levels, and the need for major revisions. This complication can be seen on imaging, but radiologists must be aware of the various components and mechanisms of failure to recognize this unique complication. We present a case of a dual-mobility construct with IPD between the femoral head components, illustrated on radiographs and CT and subsequently confirmed at the time of surgery.

Plasma FGF23 is associated with left atrial remodeling in children on hemodialysis.

BACKGROUND: FGF23 mediates cardiac fibrosis through the activation of pro-fibrotic factors in in vitro models and is markedly elevated in kidney disease. Left atrial global longitudinal strain (LA GLS) derived by echocardiographic speckle-tracking measures longitudinal shortening of the LA walls, quantifies atrial performance and may enable detection of early LA remodeling in the setting of normal ventricular function. We hypothesized that LA GLS is abnormal in children on hemodialysis (HD) compared to healthy controls of comparable age/sex distribution and that, among HD patients, greater FGF23 levels are associated with abnormal LA GLS. METHODS: Clinical and echocardiographic data from 29 children receiving HD and 13 healthy controls were collected in a cross-sectional single-center study. Plasma FGF23 concentrations were measured using ELISA. The primary outcome was LA GLS measured using 2D speckle-tracking strain analysis. Linear regression analysis was used to investigate predictors of LA GLS in HD. RESULTS: Median dialysis vintage was 1.5 (IQR 0.5-4.3) years. Median intact FGF23 levels were substantially higher in the HD vs. control group (1206 [215, 4707] vs. 51 [43, 66.5] pg/ml; P = 0.0001), and LA GLS was 39.9% SD 11.6 vs. 32.8% SD 5.7 (P = 0.04). Among HD patients, higher FGF23 was associated with lower LA GLS (ß per unit Ln-FGF23: - 2.7; 95% CI slope - 5.4, - 0.1; P = 0.04 after adjustment for age, body size, and HD vintage. FGF23 was not associated with LA phasic reservoir, conduit, or contractile strain. CONCLUSIONS: In children on HD and preserved left ventricular ejection fraction, greater FGF23 is associated with lower LA GLS (indicative of impaired atrial performance). A higher resolution version of the Graphical abstract is available as Supplementary information.

A meta-analysis of variability in conjunctival microvascular hemorheology metrics.

Conjunctival hemorheology has been used analytically to assess qualities of blood flow associated with various forms of cardiovascular disorders including diabetes mellitus, stroke, and sickle cell disease. Although conjunctival axial red blood cell velocity (Vax) has been demonstrated in varying disease states, benchmark measures of Vax are not well-defined. Due to various methodologic differences in assessment of Vax, interstudy consistency of hemorheological metrics is susceptible to both systematic and random error. Our study examines interstudy heterogeneity of Vax as measured in the conjunctival microvasculature of healthy subjects and assesses the overall perturbation of Vax based on disease state. Furthermore, our study aims to establish a potential range of normative Vax by comparing inter-study measurements in healthy patients. The most widely employed analytic approach to assess Vax was space-time analysis (n = 30). Using a meta-analytic approach, the prediction interval for Vax in healthy subjects among 20 studies ranged from 0.32-2.60 mm/s with a combined effect size of 0.52 ± 0.03 (CI: 0.46-0.59) mm/s. Inter-study comparison of Vax in healthy patients showed a high degree of variability (I2: 98.96%), due to studies with low measurement precision and/or dissimilar analytic methodology. Neither age nor diameter was a clinically significant moderator of Vax measurements in healthy patients. The combined effect size, defined as the composite Hedge's g of studies comparing healthy and disease state mean Vax, was 0.21 ± 0.13. High heterogeneity (I2: 80.48%) was observed in studies analyzing the difference between mean Vax in healthy and disease state patients. This heterogeneity was also observed when the difference in mean Vax between healthy and disease state patients was assessed in subgroups based on disease condition (I2: vascular disease 33%, sickle cell disease 62.22%, other 83.43%). Age was found to be a significant moderator (p = 0.048, ß = -0.40) of Hedge's g while diameter was not. No significant publication bias was observed in studies presenting healthy patient Vax or in studies comparing Vax between healthy and disease state patients. In summary, although homogeneity can be seen in healthy group Vax measurements, a high degree of statistical heterogeneity is found in Vax assessment comparing healthy and disease conditions that is not fully explained by methodologic variability.

3-Dimensional Bioprinting of Cardiovascular Tissues: Emerging Technology.

Three-dimensional (3D) bioprinting may overcome challenges in tissue engineering. Unlike conventional tissue engineering approaches, 3D bioprinting has a proven ability to support vascularization of larger scale constructs and has been used for several cardiovascular applications. An overview of 3D bioprinting techniques, in vivo translation, and challenges are described.

Left atrial function in children and young adult cancer survivors treated with anthracyclines.

BACKGROUND: The left atrium (LA) modulates left ventricular filling pressure and is a strong prognosticator in heart failure. Although anthracycline exposure may lead to impaired left ventricular (LV) function, the effects on LA function are not well-described in the younger population. We aim to evaluate LA function in children exposed to anthracyclines. METHODS: Children exposed to anthracyclines with pre- and post-treatment echocardiographic imaging were enrolled. Measures of LA function (LA ejection fraction [LA EF], global longitudinal strain [GLS], and peak GLS rate) were quantified using 2D speckle tracking echocardiography pre- and post-anthracycline therapy and were compared. Segments with poor tracking were excluded. RESULTS: Fifty-five children (age 13 [SD 5] years) treated with anthracyclines were evaluated. LA EF, GLS, and peak GLS rate were lower after anthracycline exposure. Mean changes were as follows: LA EF (pre-73.5 [SD 7.7]% vs post-70.6 [SD 8.2]%, P = 0.06), GLS (-34.2 [SD 8.4]% vs -31.9 [SD 7.1]%, P = 0.09), peak GLS rate (2.2 [SD 0.8] s-1 vs 2.0 [SD 0.6] s-1 , P = 0.18). When stratified by pre- (≤12 years old) vs post-puberty (>12 years old), prepubescent patients (n = 21) had statistically significant changes in pre/post LA GLS (P = 0.01) and LA EF (P = 0.01). In models adjusted for radiation dose, age, gender, body surface area, or cumulative anthracycline dose, there were no significant relationships in the absolute difference between pre/post LA EF (P = 0.34) or LA GLS (P = 0.18). CONCLUSIONS: In children exposed to anthracyclines, short-term effects on LA function were minimal in those with preserved LV EF. Age-dependent LA susceptibility to anthracycline requires further study.

Stereotactic body radiotherapy for re-irradiation of lung cancer recurrence with lower biological effective doses.

OBJECTIVE: Few studies have evaluated re-irradiation of lung cancer recurrences with stereotactic body radiotherapy (SBRT). This study evaluates outcomes with SBRT re-irradiation for recurrent lung cancer. METHODS: Two hundred and seventy-eight patients treated with SBRT for lung cancer were retrospectively reviewed. Of those, 26 patients with 29 tumors were re-irradiated with SBRT. Ninety percent of tumors received prior external beam irradiation and 10 % received prior SBRT. Previous median radiation dose was 61.2 Gy with a median 8-month interval from previous radiation. The median re-irradiation SBRT dose was 30 Gy (48 Gy10 biological effective dose (BED)). Endpoints evaluated included local control, overall survival, and progression-free survival. RESULTS: Twenty-five of 29 tumors were evaluable for local control, with 27 tumors (93 %) considered in-field recurrences. In-field crude local control rate was 80 % (20/25) with 1 and 2-year actuarial rates of 78.6 and 65.5 %, respectively. One and 2-year actuarial survival rates were 52.3 and 37.0 %, respectively. One and 2-year actuarial progression-free survival rates were 56.7 and 37.0 %, respectively. Fifty-five percent of patients reported acute/chronic grades 1 and 2 toxicities. No grade 3 or higher toxicities were reported. CONCLUSION: Patients with recurrent lung cancer have limited options. SBRT re-irradiation is tolerable even after a median 61.2 Gy to the re-irradiation site. The lower BED used provided acceptable progression-free survival with low toxicity. Given the poor prognosis with current treatment options, new paradigms for re-treatment should include SBRT-re-irradiation as an adjunct to systemic therapy for in-field lung cancer recurrence.

Nocardia keratitis after laser in situ keratomileusis: clinicopathologic correlation.

A case of Nocardia asteroides keratitis occurring 3 weeks after laser in situ keratomileusis (LASIK) in a nontraumatized eye is reported. The patient presented with decreased vision, inflammation, and stromal melting of the LASIK flap, discrete infiltrates, and an anterior chamber cellular reaction. Cultures for acid-fast bacteria grew Nocardia asteroides after 5 days. Infection progressed despite treatment with topical antibiotics and eventually required penetrating keratoplasty (PKP). Postoperatively, the patient was placed on moxifloxacin, a fourth-generation flouroquinolone. The patient experienced a recurrence of Nocardia keratitis at the graft-host interface 2 months after the PKP. This eventually resolved with a combination of topical moxifloxacin and imipenem therapy.