39 research outputs found
Can particulate extraction from the ascending aorta reduce neurologic injury in cardiac surgery?
AbstractObjectiveThis study examined whether extraction of particulate emboli using intra-aortic filtration could decrease neurologic outcomes.MethodsPatients (N = 582) were enrolled in a prospective, controlled study and alternately assigned to the therapy arm (n = 304; intra-aortic filtration) or control arm (n = 278). Preoperative, procedural, and postoperative data were collected. Neurologic examinations included the National Institutes of Health Stroke Scale, Glasgow Coma Scale, and memory tests. Investigators administering neurologic tests were blinded to the study arm. By the use of logistic regression and propensity matching, composite neurologic outcomes (transient ischemic attack, stroke, delirium, coma, and memory deficit) were evaluated.ResultsPatients in the filter group experienced a lower incidence of adverse neurologic outcomes than patients in the control group (4.3% vs 11.9%) (P < .001). There were significantly less transient ischemic attacks (0% vs 1.4%), delirium (3.0% vs 6.5%), and memory deficit (1.3% vs 6.2%). There were fewer strokes in the filter group compared with the control group (0.7% vs 2.2%), although the sample size was too small for a significant finding. Both groups experienced 1 coma outcome. The use of a filter was associated with an adjusted odds ratio of 0.375, implying that a patient who does not receive a filter is 2.7 times more likely to experience an adverse neurologic event. Logistic modeling also demonstrated that there are increasing chances of poor neurologic outcome with increasing age. The model indicates that there may be an increasing protective benefit from the filter with increasing age, although the interaction was not significant.ConclusionsThe extraction of particulate emboli using intra-aortic filtration resulted in decreased neurologic outcomes
The imbalance between proliferation and apoptosis contributes to degeneration of aortic valves and bioprostheses
Background: The pathomechanisms underlying aortic valve degeneration are incompletely understood. Therefore, the aim of our work was to assess the quantitative changes of proliferation and apoptosis accompanied by cellular phenotype alternations and matrix secretionin aortic sclerotic and stenotic valves and degenerative bioprostheses, as well as to detect the expression pattern of the rapamycin receptor FKBP12 across these three valve types.Methods: Mild-to-moderate sclerotic and stenotic valves and degenerative bioprostheses from 30 patients (n = 10 per group) were collected at autopsy or by surgery. Ki67+, FKBP12+, alpha-actin+, HSP47+ and TUNEL+ apoptotic cells were analyzed by immunohistochemistry.Results: The main finding was the reduced proliferation and increased apoptosis in stenotic valves (ST) compared to the sclerotic ones (SC) (proliferation: ST: 20.8 ± 2.0% vs. SC: 30.1 ±2.2%, apoptosis: ST: 40.7 ± 5.0% vs. SC: 28.0 ± 5.1%, p < 0.05, respectively). Analogical alternations were found in degenerative bioprostheses (BP) (proliferation: 4.8 ± 2.3%; apoptosis: 13.1 ± 6.8%). Corresponding changes were observed in the valve cellularity (ST: 893 ± 168, SC: 1034 ± 284, BP: 385 ± 179 cells/mm2, p < 0.05, respectively). The FKBP12 signaling was reduced in diseased valves and bioprostheses (ST: 28.1 ± 3.6%, SC: 42.2 ± 3.8%, BP: 5.8 ± 1.9%, p < 0.05, respectively). Further, the augmented alpha-actin expressionwas observed as the degenerative process progressed (ST: 30.3 ± 5.0%, SC: 22.6 ± 2.7%, BP:8.7 ± 4.0%, p < 0.05, respectively), followed by the upregulation of HSP47 (ST: 22.6 ± 2.8%,SC: 15.4 ± 2.1%, BP: 3.4 ± 1.0%, p < 0.05, respectively) and consecutive matrix accumulation.Conclusions: The imbalance between proliferation and apoptosis with cellular phenotypical shift and subsequent matrix secretion may contribute to aortic valve stenosis and bioprosthesis degeneration. The identification of FKBP12 expression may implicate potential therapeutic strategies
Engraftment of engineered ES cell–derived cardiomyocytes but not BM cells restores contractile function to the infarcted myocardium
Cellular cardiomyoplasty is an attractive option for the treatment of severe heart failure. It is, however, still unclear and controversial which is the most promising cell source. Therefore, we investigated and examined the fate and functional impact of bone marrow (BM) cells and embryonic stem cell (ES cell)–derived cardiomyocytes after transplantation into the infarcted mouse heart. This proved particularly challenging for the ES cells, as their enrichment into cardiomyocytes and their long-term engraftment and tumorigenicity are still poorly understood. We generated transgenic ES cells expressing puromycin resistance and enhanced green fluorescent protein cassettes under control of a cardiac-specific promoter. Puromycin selection resulted in a highly purified (>99%) cardiomyocyte population, and the yield of cardiomyocytes increased 6–10-fold because of induction of proliferation on purification. Long-term engraftment (4–5 months) was observed when co-transplanting selected ES cell–derived cardiomyocytes and fibroblasts into the injured heart of syngeneic mice, and no teratoma formation was found (n = 60). Although transplantation of ES cell–derived cardiomyocytes improved heart function, BM cells had no positive effects. Furthermore, no contribution of BM cells to cardiac, endothelial, or smooth muscle neogenesis was detected. Hence, our results demonstrate that ES-based cell therapy is a promising approach for the treatment of impaired myocardial function and provides better results than BM-derived cells