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Spasm following coronary artery bypass graft surgery has been well established in arterial grafts, especially in grafts utilizing the internal mammary. Venous graft spasms are uncommon and are only observed in vein grafts during or soon after the coronary artery bypass surgery. It is exceedingly rare to see spasm of venous graft beyond one year of surgery. We report a 72-year-old female who had coronary artery bypass graft three years ago and presented with new onset chest pain for one month. The coronary angiogram revealed severe spasm of the proximal aspect of a patent saphenous venous graft which was relieved by intracoronary nitroglycerine. Patient was successfully managed using combination of antispasmodic medications (nitrates and calcium channel blockers) leading to long-term resolution of her anginal symptoms. [ABSTRACT FROM AUTHOR]

BACKGROUND: Reoperations for bypass surgery increase the need for new grafts. We investigated early changes in both the normal human saphenous vein and in ectatic varicose veins externally supported by PTFE (polytetrafluoroethylene) graft and exposed to arterial pressure in an IN VITRO non-pulsatile flow model. MATERIAL AND METHODS: A total of 24 saphenous vein pieces (11 of them normal, the other 13 with varicosities) with a length of 6 centimeters were divided into equal parts; half of these parts were wrapped in PTFE grafts. All vein parts were placed in a perfusion circuit. Tissue biopsies were obtained from the vein segments. Light and electron microscopy examinations were performed, and endothelial continuity, elastic laminate continuity, medial connective tissue uniformity, medial smooth muscle uniformity, and adventitial connective tissue uniformity parameters were identified. RESULTS: All parameters in the PTFE protected vein groups were better. The fewest morphological changes among all four groups were detected in the vein walls from normal veins with PTFE protection. There was no significant difference in endothelial continuity and adventitial connective tissue uniformity between the normal vein group and the varicose vein group with PTFE protection. CONCLUSIONS: It is suggested that supporting vein grafts externally with PTFE sufficiently protects the vein walls against damage from exposure to arterial pressure. If varicose veins are used as arterial grafts, supporting them with PTFE may be useful because of the good protection of endothelial and medial connective tissues, resulting in similar parameters to those of normal vein walls. [ABSTRACT FROM AUTHOR]

Tomographic biomedical images are commonly affected by an imaging artefact known as the partial volume (PV) effect. The PV effect produces voxels composed of a mixture of tissues in anatomical magnetic resonance imaging (MRI) data resulting in a continuity of these tissue classes. Anatomical MRI data typically consist of a number of contiguous regions of tissues or even contiguous regions of PV voxels. Furthermore discontinuities exist between the boundaries of these contiguous image regions. The work presented here probabilistically models the PV effect using spatial regularization in the form of continuous Markov random fields (MRFs) to classify anatomical MRI brain data, simulated and real. A unique approach is used to adaptively control the amount of spatial regularization imposed by the MRF. Spatially derived image gradient magnitude is used to identify the discontinuities between image regions of contiguous tissue voxels and PV voxels, imposing variable amounts of regularization determined by simulation. Markov chain Monte Carlo (MCMC) is used to simulate the posterior distribution of the probabilistic image model. Promising quantitative results are presented for PV classification of simulated and real MRI data of the human brain. [ABSTRACT FROM AUTHOR]

Background: Techniques to preserve the sub-valvular apparatus in order to reduce morbidity and mortality following mitral valve replacement have been frequently reported. However, it is uncertain what impact sub-valvular apparatus preservation techniques have on long-term outcomes following mitral valve replacement. This study investigated the effect of sub-valvular apparatus preservation on long-term survival and quality of life following mitral valve replacement. Methods: A microsimulation model was used to compare long-term survival and quality-adjusted life years following mitral valve replacement after conventional valve replacement and sub-valvular apparatus preservation. Probabilistic sensitivity analysis and alternative analysis were performed to investigate uncertainty associated with the results. Results: Our Analysis suggests that patients survive longer if the sub-valvular apparatus are preserved (65.7% SD 1.5%, compared with 58.1% SD 1.6% at 10 years). The quality adjusted life years gained over a 10 year period where also greater after sub-valvular apparatus preservation. (6.54 QALY SD 0.07 QALY, compared with 5.61 QALY, SD 0.07 QALY). The superiority of preservation techniques was insensitive to patient age, parameter or model uncertainty. Conclusion: This study suggests that long-term outcomes may be improved when the sub-valvular apparatus are preserved. Given the lack of empirical data further research is needed to investigate health-related quality of life after mitral valve replacement, and to establish whether outcomes differ between preservation techniques. [ABSTRACT FROM AUTHOR]

Focuses on the late complications of arterial grafts. Complications associated with the insertion of vascular grafts; Causes of anastomotic aneurysms; Factors to increase survival of grafts.

A case of coarctation of the abdominal aorta, diagnosed as such preoperatively and treated with a homologous arterial graft, preserved for 42 days, is presented. Its functioning had been shown by oscillometry; nevertheless this therapy did not have any repercussion on the generalized hypertensive picture, rather a worsening of the renal function was observed. [ABSTRACT FROM AUTHOR]

The article presents an opinion on the use of hypogastric branch device during endovascular abdominal aortic aneurysm repair with iliac aneurysms. There are benefits of preserving an internal iliac artery. The hypogastric branch devices was successful in terms of maintaining a patent branch. The application of this approach, however, is a challenge for physicians.