Biomedical subjects

Dietmar Glogar

Publications and source records attributed to Dietmar Glogar.

39 records · Page 3Linked to original sources

PubMed2002

Mechanism of lumen gain during coronary stent deployment in diabetic patients compared with non-diabetic patients.

BACKGROUND: Diabetic patients show an increased incidence of restenosis after coronary angioplasty than non-diabetic patients. This may be because of differences in the mechanism of lumen gain during coronary revascularization in this population cohort. DESIGN: This study analyses the mechanism of lumen gain during coronary stent deployment in diabetic patients compared with non-diabetic patients with intravascular ultrasound (IVUS). METHODS: IVUS images were obtained prior to and after revascularization in 26 diabetic and 97 non-diabetic patients. The external elastic membrane cross-sectional area (EEM) and lumen cross-sectional area (LA) were measured. Plaque area (PA) was calculated as EEM minus LA. Differences between pre- and post-LA (deltaLA), EEM (deltaEEM) and PA (deltaPA) were calculated. RESULTS: Pre-interventional PA (diabetic patients: 12.4 +/- 4.4 mm2 compared with non-diabetic patients: 10.7 +/- 3.6 mm2, = 0.04) and pre-interventional EEM (15.5 +/- 4.4 mm2 compared with 13.6 +/- 3.7 mm2 respectively, P = 0.02) were larger in the diabetic group. Postinterventional PA (10.2 +/- 3.2 mm2 compared with 8.0 +/- 3.4 mm2, P = 0.004) was also larger and postinterventional LA (6.3 +/- 2.2 mm2 compared with 7.4 +/- 2.4 mm2 = 0.04), deltaEEM (0.9 +/- 1.8 mm2 compared with 1.8 +/- 1.8 mm2 P = 0.04) and deltaLA (3.1 +/- 1.6 mm2 compared with 4.2 +/- 2.2 mm2, P = 0.03) were smaller in the diabetic group. The diabetic group exhibited longer lesion lengths (P = 0.04) and a higher inflation pressure was used during revascularization in this patient cohort (P = 0.02). CONCLUSION: Diabetic patients have less reduction of PA during revascularization and because the vessel wall cannot be stretched outwards despite higher inflation pressure, postinterventional LA remains smaller than in the non-diabetic population cohort. This might be a rudiment for consideration of different treatment strategies such as cutting balloon or atherectomy prior to stenting in this population group in order to achieve better procedural outcome.

Aged↗

PubMed2002

Usefulness of intravascular ultrasound-guided histological measurements after stenting in porcine coronary artery.

BACKGROUND: We evaluated the usefulness of intravascular ultrasound (IVUS) in the non-uniform distribution of in-stent neointimal hyperplasia, comparing macroscopic measurements with IVUS-guided histomorphometry. METHODS: Coronary stenting was performed in 45 left coronaries of 39 pigs, using 18 Tenax (Biotronik Gmbh and Co., Berlin, Germany), 11 bare Genius (Eurocor, Bonn, Germany), 10 polymer-coated Genius (Eurocor) and six Biodivysio Matrix LO (Biodivysio Ltd, Farnham, Surrey, UK) stents. After 4 weeks, coronary angiography and IVUS with automatic pullback were performed. IVUS images were analysed using three-dimensional analysis (EchoPlaque 2; INDEC Systems Inc., Mountain View, California, USA). The stented segments were formalin fixed, embedded in Technovit 9100 and cut to 4-8 microm thick slides. The most diseased in-stent segment was 4.49 +/- 4.54 mm away from the distal stent edge assessed by IVUS. Sections of these segments were stained for histomorphometry. RESULTS: A significant correlation was found between IVUS-guided histomorphometry and three-dimensional IVUS measurements of maximal intimal thickness (r = 0.6985, P < 0.005) and area (r = 0.7736, P < 0.001). Macroscopic measurements resulted in comparable maximal intimal thickness (0.83 +/- 0.43 mm compared with 0.81 +/- 0.46 mm) and area (4.44 +/- 1.73 mm2 compared with 3.45 +/- 1.55 mm2) by IVUS and histomorphometry, respectively. Although stent length, diameter, nominal inflation pressure and time and injury score did not differ between the stents, bare Genius stents resulted in significant smaller neointimal volume compared to Tenax, polymer-coated Genius and Biodivysio stents: 24.46 +/- 4.98 mm3 compared with 59.18 +/- 26.41, 60.46 +/- 10.03 and 61.41 +/- 16.27 mm3, respectively (P < 0.05). CONCLUSION: The significant correlation between IVUS-guided histomorphometry and IVUS measurements confirms the usefulness of IVUS in evaluation of experimental in-stent restenosis. Implantation of bare Genius stents resulted in significant lower neointimal hyperplasia compared to Tenax, polymer-coated Genius or phosphorylcholine-coated Biodivysio stents.

Animals↗

PubMed2002

Prevention of stent thrombosis following brachytherapy and implantation of drug-eluting stents.

The implementation of coronary brachytherapy and especially the application of drug-eluting stents for the prevention of in-stent restenosis are of vital importance in the field of interventional cardiology. Despite undeniable benefits of these new methods a potential increased risk for the occurrence of stent thrombosis as a result of the mode of action of these new methods has to be taken into consideration. The prevention of stent thrombosis following coronary brachytherapy and implantation of drug-eluting stents is therefore of particular importance to assure the success of these forward-looking technologies. This article provides an overview of current data regarding the incidence of stent thrombosis following brachytherapy and implantation of drug-eluting stents and it's implication for clinical practice.

Angioplasty, Balloon, Coronary↗