Murat Gülbaran

Increased secretion of insulin during oral glucose tolerance test can be a predictor of stent restenosis in nondiabetic patients

Insulin is known to stimulate proliferation and migration of vascular smooth muscle cells. As the predominant mechanism of restenosis after stent implantation is neointimal tissue proliferation, one can expect a relationship between hyperinsulinemia and restenosis in these patients. The aim of this study was to determine whether hyperinsulinemia during oral glucose tolerance test is a predictor of the development of restenosis after stent implantation in nondiabetic patients. We prospectively studied 52 nondiabetic patients with effort angina who underwent elective stent implantation for single‐vessel coronary artery disease. In order to increase the statistical power of the study, numerous exclusion criteria were applied. All patients were subjected to a 75 g oral glucose tolerance test a day before the stent implantation and underwent follow‐up angiography 6 months later. Plasma insulin levels in fasting (6.77 ± 1.57 vs. 5.36 ± 1.35 μU/ml; P = 0.005), at 30 min (102.48 ± 10.6 vs. 47.74 ± 12.75 μU/ml; P = 0.001), 1 hr after (120.23 ± 14.1 vs. 63.08 ± 12.62 μ/ml; P = 0.001), 2 hr after (63.58 ± 8.64 vs. 34.88 ± 6.82 μ/ml; P = 0.001), and 3 hr after (25.71 ± 5.65 vs. 23.02 ± 4.61 μ/ml; P = 0.04) loading were significantly higher in patients with stent restenosis than in patients without stent restenosis. Insulin area and insulin area/glucose area were also significantly higher in patients with stent restenosis than in patients without (219.5 ± 23.8 vs. 118.9 ± 21.8, P = 0.001, and 0.62 ± 0.09 vs. 0.33 ± 0.06, P = 0.001, respectively). By multiple logistic regression analysis, insulin area during oral glucose tolerance test was found to be an independent predictor of stent restenosis (OR = 1.12; 95% CI = 1.01–1.25; P = 0.031). In conclusion, nondiabetic patients with hyperinsulinemia during oral glucose tolerance test have a high risk for restenosis after stent implantation, and performing this simple test before intervention may be useful for the prediction of stent restenosis. Cathet Cardiovasc Intervent 2003;58:306–312.

Intravascular radiation therapy with a Re-188 liquid-filled balloon in patients with in-stent restenosis.

ObjectiveThe aim of this study was to evaluate the feasibility and safety of intravascular radiation therapy (IVRT) using Re-188 filled balloon system in patients with in-stent stenosis. MethodsA total of 39 patients with in-stent restenosis were enrolled as the IVRT (22 patients) and control groups (17 patients) of this study after a successful coronary angioplasty. For irradiation the angioplasty balloon was replaced by a noncompliant balloon of the same diameter but 10 mm longer in length with a proximal and distal radio-opaque marker to deliver the dose of 18 Gy at 0.5 mm depth from the surface of the balloon into the vessel wall. Angiographic follow-up was performed after 6 months. ResultsThe length of the irradiated segment was between 9.14 and 22 mm and the diameter between 2.5 and 3 mm. In the IVRT group, two patients who did not receive antiplatelet therapy had myocardial infarction. Four patients who presented with stable angina earlier also had angiographically documented in-stent occlusion (two patients) and edge stenosis (two patients) of the target lesion and received angioplasty (18.1%). In the control group, three patients with recurrent angina and four asymptomatic patients had documented in-stent occlusion angiographically at 6 months and these seven patients underwent target lesion revascularization (41.2%). The overall restenosis rate in the IVRT and control groups were 23.91 and 39.86%, respectively (P=0.013). No complications were documented, except anginal pain and ST segment changes. ConclusionOur results indicated that the Re-188 liquid-filled balloon is feasible, safe, and effective in patients with in-stent restenosis.

Revascularization of chronic coronary artery occlusions using laser debulking followed by stent implantation.

Objective — Chronic total occlusions are considered unfavourable for percutaneous balloon angioplasty because of the low rate of success and the high rate of restenosis. Stent implantation after recanalization of chronic total occlusions has been shown to reduce restenosis and reocclusion rates compared with balloon angioplasty in recently published randomized trials. However, it is not well known whether laser debulking before stent implantation would improve the benefit of stenting in chronic total occlusions. Methods and results — We analysed procedural and long-term clinical and angiographic followup results of 48 patients who underwent laser angioplasty followed by stent implantation for chronic total occlusions. The procedure was completed successfully in 46 patients (95.8%) in whom the lesion was crossed with a guidewire.We implanted 51 stents in 46 chronic total occlusions following laser debulking. During in-hospital follow-up 1 patient (2.1%) had Q wave, and 4 patients (8.7%) had non-Q wave myocardial infarction. Nine patients (19.5%) had repeat angioplasty for restenosis and one (2.1%) underwent coronary bypass operation at 6 months follow-up. Death or Q wave myocardial infarction did not occur during 6-month follow-up.Thirty-nine patients (85%) had angiographic follow-up at 6 months, and stent restenosis was found in 17 (44%) patients. Conclusion — These high rates of restenosis and target vessel revascularization in our study suggest that laser debulking before stent implantation does not improve clinical and angiogragic outcomes in chronic total occlusions.

Ein chronisches Koronarpseudoaneurysma nach Stentimplantation

Um die Rate akuter und subakuter Stentthrombosen zu vermindern, werden Stents nach der neuen Technik mit hohem Druck und/oder mit Enddilatation durch größere Ballons in Koronarstenosen implantiert. In dieser Arbeit wird über ein chronisches Koronarpseudoaneurysma berichtet, das nach einer erfolgreichen Stentimplantation im Ramus interventricularis anterior wahrscheinlich wegen Enddilatation mit sehr hohem Druck aufgetreten ist. Recently, as a part of new stent implantation strategy in order to decrease stent thrombosis, final dilatations with high pressure and/or higher sized balloons were applied after the initial deployment of the stent. In this paper, we presented a case of chronic coronary pseudoaneurysm which occured after an initially successful stent implantation in the left anterior descending artery, probably due to high pressure final dilatation.