Long-term quality of life and mobility after prosthetic above-the-knee bypass surgery

A systematic review of patient-reported outcome measures patients with chronic limb-threatening ischemia

Chronic limb-threatening ischemia (CLTI) causes significant morbidity with profound negative effects on health-related quality of life. As the prevalence of peripheral artery disease and diabetes continue to rise in our aging population, the public health impact of CLTI has escalated. Patient-reported outcome measures (PROMs) have become common and important measures for clinical evaluation in both clinical care and research. PROMs are important for the measurement of clinical effectiveness and cost effectiveness and for shared decision-making on treatment options. However, the PROMs used to describe the experience of patients with CLTI are heterogeneous, incomplete, and lack specific applicability to the underlying disease processes and diverse populations. For example, certain PROMs exist for patients with extremity wounds, and other PROMs exist for patients with pain, and still others exist for patients with vascular disease. Despite this multiplicity of tools, no single PROM encompasses all of the components necessary to describe the experiences of patients with CLTI. This significant unmet need is evident from both published reports and contemporary large-scale clinical trials in the field. In this systematic review, we review the current use of PROMs for patients with CLTI in clinical practice and in research trials and highlight the gaps that need to be addressed to develop a unifying PROM instrument for CLTI.

In vitro recellularization of decellularized bovine carotid arteries using human endothelial colony forming cells

BACKGROUND

Many patients suffering from peripheral arterial disease (PAD) are dependent on bypass surgery. However, in some patients no suitable replacements (i.e. autologous or prosthetic bypass grafts) are available. Advances have been made to develop autologous tissue engineered vascular grafts (TEVG) using endothelial colony forming cells (ECFC) obtained by peripheral blood draw in large animal trials. Clinical translation of this technique, however, still requires additional data for usability of isolated ECFC from high cardiovascular risk patients. Bovine carotid arteries (BCA) were decellularized using a combined SDS (sodium dodecyl sulfate) -free mechanical-osmotic-enzymatic-detergent approach to show the feasibility of xenogenous vessel decellularization. Decellularized BCA chips were seeded with human ECFC, isolated from a high cardiovascular risk patient group, suffering from diabetes, hypertension and/or chronic renal failure. ECFC were cultured alone or in coculture with rat or human mesenchymal stromal cells (rMSC/hMSC). Decellularized BCA chips were evaluated for biochemical, histological and mechanical properties. Successful isolation of ECFC and recellularization capabilities were analyzed by histology.

RESULTS

Decellularized BCA showed retained extracellular matrix (ECM) composition and mechanical properties upon cell removal. Isolation of ECFC from the intended target group was successfully performed (80% isolation efficiency). Isolated cells showed a typical ECFC-phenotype. Upon recellularization, co-seeding of patient-isolated ECFC with rMSC/hMSC and further incubation was successful for 14 (n = 9) and 23 (n = 5) days. Reendothelialization (rMSC) and partial reendothelialization (hMSC) was achieved. Seeded cells were CD31 and vWF positive, however, human cells were detectable for up to 14 days in xenogenic cell-culture only. Seeding of ECFC without rMSC was not successful.

CONCLUSION

Using our refined decellularization process we generated easily obtainable TEVG with retained ECM- and mechanical quality, serving as a platform to develop small-diameter (< 6 mm) TEVG. ECFC isolation from the cardiovascular risk target group is possible and sufficient. Survival of diabetic ECFC appears to be highly dependent on perivascular support by rMSC/hMSC under static conditions. ECFC survival was limited to 14 days post seeding.

Cells and stimuli in small-caliber blood vessel tissue engineering

The absence of successful solutions in treatments of small-caliber vessel diseases led to the Vascular Tissue Engineering approach to develop functional nonimmunogenic tissue engineered blood vessels. In this context, the choice of cells to be seeded and the microenvironment conditioning are pivotal. Biochemical and biomechanical stimuli seem to activate physiological regulatory pathways that induce the production of molecules and proteins stimulating stem cell differentiation toward vascular lineage and reproducing natural cross-talks among vascular cells to improve the maturation of tissue engineered blood vessels. Thus, this review focuses on (1) available cell sources, and (2) biochemical and biomechanical stimuli, with the final aim to obtain the long-term stability of the endothelium and mechanical properties suitable for withstanding physiological load.

Changes in functional status after treatment of critical limb ischemia

OBJECTIVE

This study evaluated changes in functional status with the Academic Medical Center Linear Disability Score (ALDS) and in quality of life with the Vascular Quality of Life Questionnaire (VascuQol) in patients treated for critical limb ischemia (CLI).

METHODS

We conducted a prospective observational cohort study in a single academic center that included consecutive patients with CLI who presented between May 2007 and May 2010. The ALDS and VascuQol questionnaires were administered before treatment (baseline) and after treatment at 6 and 12 months of follow-up. Changes in functional status (ALDS) and quality of life (VascuQol) scores after 6 and 12 months, compared with baseline, were tested with the appropriate statistical tests, with significance set at P < .05.

RESULTS

The study included 150 patients, 96 (64%) were men, and mean (± standard deviation) age was 68.1 (± 12.4) years. The primary treatment was endovascular in 98 (65.3%), surgical in 36 (24%), conservative in 11 (7.3%), or a major amputation in five (3.3%). The ALDS was completed by 112 patients after 12 months. At that time, the median ALDS score had increased by 10 points (median, 83; range, 12-89; P = .001) in patients who achieved limb salvage, which corresponds with more difficult outdoor and indoor activities. In patients with a major amputation, the median ALDS score decreased by 14 points (median, 55; range, 16-89; P = .117) after 12 months, which corresponds with domestic activities only. VascuQol scores improved significantly in all separate domains for the limb salvage group (P < .001). All VascuQol scores, except for the activity and social domains, increased significantly after amputation.

CONCLUSIONS

Our study confirms the clinical validity of the ALDS in patients treated for CLI and shows that it is a valuable and sophisticated instrument to measure changes in functional status in these patients.