Toward acellular xenogeneic heart valve prostheses: Histological and biomechanical characterization of decellularized and enzymatically deglycosylated porcine pulmonary heart valve matrices

The use of decellularized xenogeneic heart valves might offer a solution to overcome the issue of human valve shortage. The aim of this study was to revise decellularization protocols in combination with enzymatic deglycosylation, in order to reduce the immunogenicity of porcine pulmonary heart valves, in means of cells, carbohydrates, and, primarily, Galα1-3Gal (α-Gal) epitope removal. In particular, the valves were decellularized with sodium dodecylsulfate/sodium deoxycholate (SDS/SD), Triton X-100 + SDS (Tx + SDS), or Trypsin + Triton X-100 (Tryp + Tx) followed by enzymatic digestion with PNGaseF, Endoglycosidase H, or O-glycosidase combined with Neuraminidase. Results showed that decellularization alone reduced carbohydrate structures only to a limited extent, and it did not result in an α-Gal free scaffold. Nevertheless, decellularization with Tryp + Tx represented the most effective decellularization protocol in means of carbohydrates reduction. Overall, carbohydrates and α-Gal removal could strongly be improved by applying PNGaseF, in particular in combination with Tryp + Tx treatment, contrary to Endoglycosidase H and O-glycosidase treatments. Furthermore, decellularization with PNGaseF did not affect biomechanical stability, in comparison with decellularization alone, as shown by burst pressure and uniaxial tensile tests. In conclusion, valves decellularized with Tryp + Tx and PNGaseF resulted in prostheses with potentially reduced immunogenicity and maintained mechanical stability.     

Temsirolimus in Daily Use: Results of a Prospective Multicentre Noninterventional Study of Patients with Metastatic Kidney Cancer

Background

Temsirolimus (TEMSR) was approved for treating advanced renal cell carcinoma (RCC) in 2007. Based on the data from a single phase 3 trial, it is recommended explicitly as first-line therapy for patients with a poor clinical prognosis.

Objective

The aim of this prospective multicentre trial (STARTOR) was to examine the effectiveness of TEMSR in daily clinical practice with a broader indication in the treatment of metastatic RCC.

Design, setting, and participants

Metastatic RCC patients treated with 25 mg of TEMSR weekly were submitted to a prospective systematic evaluation and follow-up in 87 German centres between January 2008 and October 2011 using standardised procedures.

Outcome measurements and statistical analysis

All data were centrally analysed by an independent clinical research organisation.

Results and limitations

This interim analysis of the STARTOR study included 386 patients. The observed toxicity was tolerable, the median dose intensity was 91% (interquartile range: 79–100%), and the median treatment duration was 20.1 wk (95% confidence interval [CI], 17.0–23.3 wk). Clinical benefit was seen in 157 patients (40.7%); the median progression-free and overall survival were 4.9 mo (95% CI, 4.2–5.6) and 11.6 mo (95% CI, 9.3–13.9), respectively. The effectiveness of TEMSR did not differ significantly in relation to the patient's age, histologic RCC subtype, or line of treatment. The major limitations were the noninterventional study design, limited information about Memorial Sloan-Kettering Cancer Center risk factors and detailed toxicity, and the lack of central radiologic review.

Conclusions

TEMSR is an effective and largely well-tolerated treatment alternative for metastatic RCC patients in daily clinical practice, irrespective of the patient's age, histologic RCC subtype, or line of treatment.     

Electrocardiographic evolution of interatrial conduction consistent with Bayés syndrome after transcatheter aortic valve implantation

Journal of Interventional Cardiac Electrophysiology -     

Systematic review of the evaluation and management of coronary pseudoaneurysm after stent implantation

Pseudoaneurysm (PSA) formation is a rare but well-known complication of coronary stenting. It develops after a procedural perforation disrupts the integrity of the vessel wall but is contained by a single wall layer, usually pericardium, extravascular thrombosis and later fibrosis. Medical literature of PSA consists primarily of case reports. A systematic review of pseudoaneurysm after coronary stenting was performed to summarize its presentation, diagnostic imaging modalities, natural history, and management approaches. Clinical presentations range from asymptomatic to hemodynamic collapse, size from small to “giant,” and treatment approaches from surgical or percutaneous exclusion to “watchful waiting” and imaging surveillance. Based on current information, a management algorithm is provided recommending urgent to emergent exclusion for symptomatic PSA, elective exclusion for large and giant PSA, and “watchful waiting” and periodic imaging surveillance for small to moderate sized PSA.