Biomedical subjects

Robert Gil

Publications and source records attributed to Robert Gil.

5 recordsLinked to original sources

PubMed2003

Stenting of culprit lesions in unstable angina leads to a marked reduction in plaque burden: a major role of plaque embolization? A serial intravascular ultrasound study.

BACKGROUND: Intravascular ultrasound (IVUS) studies have shown that a mechanism of plaque compression/embolization contributes toward the poststenting increase in lumen area. The aim of this IVUS study was to compare the mechanisms of lumen enlargement after coronary stenting in 54 consecutive patients with unstable angina (UA) (group 1) and 56 with stable angina (group 2) to verify whether plaque embolization plays a major role in the former. METHODS AND RESULTS: Both groups underwent the IVUS assessment (speed, 0.5 mm/sec) before the intervention and after stent implantation. The lumen area, the external elastic membrane area, and the plaque+media area (PA) were measured at 0.5-mm intervals. PA reduction in the lesion site was significantly greater in group 1 (-2.50+/-1.97 versus -0.53+/-1.43 mm2, P<0.001). After stenting, 47% of the lumen area increase in group 1 was obtained by means of PA reduction, and 53% was attributable to external elastic membrane area increase; the corresponding figures in group 2 were 13% and 87% (P<0.05). Decrease in PA after stenting was the only significant predictor of the MB fraction of creatinine kinase (CK-MB) release in a multiple regression model (P=0.047). CONCLUSIONS: Serial volumetric IVUS assessment revealed in UA lesions a marked poststenting reduction in plaque volume, which is significantly greater than in stable angina and is associated with postprocedural CK-MB release. The decrease in PA during the procedure predicts CK-MB release in a multiple regression model. These findings suggest that stent deployment is often associated with plaque embolization in patients with UA.

Angina Pectoris↗

PubMed2003

Heparin-coated stent placement for the treatment of stenoses in small coronary arteries of symptomatic patients.

BACKGROUND: The role of stents, especially of heparin-coated stents for the treatment of stenoses in small coronary arteries, is still unclear. Therefore, we performed this prospective, randomized trial to evaluate the angiographic and clinical outcome after treatment of stenoses in small coronary arteries (2.0 to 2.6 mm) of symptomatic patients. METHODS AND RESULTS: We randomly assigned 588 patients to angioplasty (n=195), bare stenting (n=196), or heparin-coated stenting (n=197). The primary end point was minimal lumen diameter (MLD) at 6 months. With comparable baseline parameters, the two stent arms showed a larger postinterventional MLD, larger acute gain, and smaller residual percent diameter stenosis, although a residual stenosis of 12+/-16% was achieved in the angioplasty arm, including a 27% crossover rate to stenting. Eighty percent of patients had follow-up angiography, which documented a borderline significantly larger MLD and smaller percent diameter stenosis for the two stent groups (1.34+/-0.48 mm and 42+/-20% after angioplasty, 1.47+/-0.48 mm and 36+/-20% after bare stenting, and 1.45+/-0.54 mm and 38+/-23% after heparin-coated stenting; P=0.049 and P=0.038, respectively), but restenosis rates were not different (32%, 25%, and 30%). Thrombotic events occurred in 1.0% after angioplasty and 0.5% after bare or heparin-coated stenting. Survival without myocardial infarction or target vessel revascularization at 250 days was 84.6% (angioplasty), 88.3% (bare stenting), and 88.3% (heparin-coated stenting; log-rank P=0.39). CONCLUSION: Compared with angioplasty with provisional stenting, bare and heparin-coated stenting confer superior angiographic results and a nonsignificant 24% reduction in clinical events, with no difference between bare and heparin-coated stenting in the treatment of stenoses in small coronary arteries.

Angioplasty, Balloon, Coronary↗

PubMed2003

[Remodeling of coronary arteries examined by arteries intravascular ultrasonography].

UNLABELLED: In most papers atherosclerotic remodelling was assessed in one segment of each studied artery. Such mode of study makes impossible to investigate the homogeneity of the remodelling. The aim of the study was intravital assessment by means of intravascular ultrasonography (IVUS) of the incidence of positive and negative remodelling in coronary artery segments and verification of the hypothesis that remodelling is inhomogeneous within the same artery. METHOD: Remodelling was assessed quantitatively by IVUS (3.5 F; 20 MHz Visions Five-64 F/X catheters, Oracle In-Vision Imaging System, Endosonics Corp. USA) in 48 segments of 27 coronary arteries. On the base of the difference between total vessel area (TA) at lesion site and reference cross-section (plaque area < 35%) remodelling was classified as negative, positive or absent. In 13 arteries out of 27 studied arteries more than 1 segment was assessed, containing both cross-section with > 50% stenosis and reference cross-section. RESULTS: Positive, negative and absent remodelling was observed in 54%, 29% and 17% of segments, respectively. The analysis revealed two different types of remodelling in 7 out of 13 arteries with several analysed segments. This finding demonstrates that remodelling is inhomogenous within the artery (p < 0.006). CONCLUSIONS: Compensatory enlargement is the most common response of coronary arteries to atherosclerotic plaque development followed by negative remodelling and absence of remodelling. Not homogenous remodelling within the same artery suggests a prominent role of local factors in determining the type of response of the artery to plaque accumulation.

Adult↗

PubMed2002

[Doppler echocardiographic evaluation of left ventricular diastolic function in patients with hypertrophic obstructive cardiomyopathy after alcohol septal ablation in acute and long-term follow up].

UNLABELLED: Left ventricular (LV) diastolic dysfunction is responsible for most clinical symptoms in hypertrophic cardiomyopathy. The left ventricular outflow tract (LVOT) obstruction has additional negative haemodynamic influence. Alcohol septal ablation reduces the LVOT gradient. CEL The aim of our study was the evaluation of acute and long-term changes of LV diastolic function after successful alcohol septal ablation. MATERIAL AND METHODS: In 15 patients with successful reducing of LVOT gradient the LV diastolic function was assessed using Doppler echocardiography before ablation and in short and long-term follow-up. RESULTS: Before ablation IVRT and DT were prolonged in comparison to normal values. In acute phase after ablation E/A ratio decreased from 1.19 +/- 0.36 to 0.89 +/- 0.27 (p < 0.01), but returned to baseline by the first week. In long-term follow-up there was again a significant reducing of E/A ratio (mainly due to E wave changes). IVRT was significantly shortened from 98 +/- 20 ms at baseline to 80.5 +/- 17 ms at day 7 and later. This change was stable to the end of follow-up. DT did not change significantly just after the ablation and during follow-up. CONCLUSIONS: In the acute period after alcohol septal ablation there is an increase of LV relaxation disorders. Changes observed during long-term follow-up are difficult to interpret, but significant shortening of IVRT shows on improvement of the LV diastolic function.

Adult↗

PubMed2002

[Not Available].

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Journal Article↗