Stent restenosis and thrombosis: etiology, treatment, and outcomes.

The implementation of bare metal stents and later drug eluting stents (DES) proved to be an important step forward in reducing rates of restenosis after percutaneous coronary intervention. Despite all the benefits of DES, concerns have been raised over their long term safety as especially stent thrombosis sets patients at risk. In view of the overall low frequency of stent thrombosis, large sample sizes are needed to evaluate accurately treatment differences between stents. However, a consistent finding from randomized, controlled trials of DES versus bare metal stents is the significantly reduced reintervention rate associated with DES use. The clinical presentation of restenosis is recurrent angina or acute coronary syndrome. Optimal implantation of the stent in the vessel and adequate antiplatelet therapy are of utmost significance to provide best results. Intravascular imaging often helps to provide optimal delivery of the stent. Newer stents have now been developed. Especially DES with biogradable polymers, novel coatings of the stent, and polymer free DES have to be mentioned and early results seem to be promising. The perspective of bioresorbable DES platforms includes the additional benefits of improved recovery in vessel function and the potential for reducing the requirement for prolonged dual antiplatelet therapy. This article reviews the etiology, treatment options and outcome of in stent restenosis and gives an overview about the new developments in the field of stent technology.

The effect of chordal preservation on late outcome after mitral valve replacement: a randomized study.

Postoperative survival, hemodynamic status and exercise tolerance with or without posterior chordal preservation were compared in a case-limited prospective randomized manner in 100 patients who underwent isolated mitral valve replacement with size 29mm or 31mm St. Jude Medical prostheses. The preoperative clinical and hemodynamic parameters were comparable in the two groups. The mean follow up was 293.3 months for those with and 263.1 months for patients without chordal preservation. Right heart cardiac catheterization was performed in every patients at the end of the follow up period and it demonstrated significantly better results with than without chordal preservation (cardiac index 2.81 +/- 0.47 vs. 2.63 +/- 0.52, p < 0.05; pulmonary arterial pressure 30 +/- 11 mmHg vs. 37 +/- 13 mmHg at 30 Watts bicycle exercise, p < 0.01; end-diastolic volume index 75 +/- 22 vs. 86 +/- 38 ml/m2, p < 0.02; and maximum exercise tolerance 1.8 +/- 0.3 vs. 1.2 +/- 0.5 Watt/kg, p < 0.01). Actuarial freedom from complications was 78.1 +/- 4.2% with and 70.7 +/- 6.2% without chordal preservation (p < 0.02). In particular, patients with severe mitral regurgitation benefited from the preservation of the posterior mitral leaflet with its chordal and papillary structure (p < 0.001).