Change In Diameter Stenosis Research Articles

Effect of Homocysteine-Lowering B Vitamin Treatment on Angiographic Progression of Coronary Artery Disease: A Western Norway B Vitamin Intervention Trial (WENBIT) Substudy

Total plasma homocysteine (tHcy) is an independent risk factor for coronary artery disease, and tHcy is lowered by B vitamins. To assess the effect of homocysteine-lowering B-vitamin treatment on angiographic progression of coronary artery disease, this substudy of the Western Norway B Vitamin Intervention Trial (WENBIT) included patients who had undergone percutaneous coronary intervention. The patients were randomized to daily oral treatment with folic acid, vitamin B(12), and vitamin B(6) or placebo in a 2 x 2 factorial design. The coronary angiograms obtained at baseline and follow-up were evaluated. The primary angiographic end points were the changes in minimum lumen diameter and diameter stenosis. A total of 348 subjects (288 men) with a mean +/- SD age of 60 +/- 10.2 years were followed up for a median of 10.5 months (twenty-fifth, seventy-fifth percentile 9.2, 11.8). The baseline median plasma tHcy level was 10.0 mumol/L (twenty-fifth, seventy-fifth percentile 8.1, 11.0), and treatment with folic acid/vitamin B(12) lowered the tHcy levels by 22%. At follow-up, we found 309 lesions with a significant decrease from baseline in the minimum lumen diameter of a mean of -0.16 +/- 0.4 mm and an increase in the diameter stenosis of 4.4 +/- 0.7%. Treatment with folic acid/vitamin B(12) or vitamin B(6) was not associated with a change in diameter stenosis or minimum lumen diameter. In a post hoc analysis, folic acid/vitamin B(12) treatment was significantly associated with rapid progression (odds ratio 1.84, 95% confidence interval 1.07 to 3.18). In conclusion, vitamin B treatment showed no beneficial effect on the angiographic progression of coronary artery disease, and the post hoc analyses suggested that folic acid/vitamin B(12) treatment might promote more rapid progression.

Impact of Iodinated Contrast Injections on Percent Diameter Coronary Arterial Stenosis and Implications for Trials of Intracoronary Pharmacotherapies in Patients With ST-Elevation Myocardial Infarction

Administration of fibrinolytic, antiplatelet, and antithrombotic agents by the intracoronary route may disaggregate clot, but the potential role of the mechanical force of the injection itself in decreasing clot burden has not been studied. Patients with ST-segment elevation myocardial infarction who were pretreated in the emergency room (ER) with unfractionated heparin and aspirin in the TITAN-TIMI 34 study were randomized to treatment with eptifibatide in the ER (n = 131) versus after diagnostic catheterization (n = 150). Quantitative coronary angiography was used to assess change in diameter stenosis from time of first contrast injection to injection before percutaneous coronary intervention (PCI) immediately preceding wire placement down the culprit artery in a matching view. Successful perfusion of the myocardium was assessed after PCI by the presence of Thrombolysis In Myocardial Infarction myocardial perfusion grade of 2 or 3. In patients treated with eptifibatide in the ER, there was a 1.3% absolute improvement in diameter stenosis from the first injection to the injection before PCI (p = 0.02), whereas there was no change in diameter stenosis in patients not treated with eptifibatide in the ER (0.0%, p = NS). Each 1% improvement in percent diameter stenosis during diagnostic injections before PCI was strongly correlated with an open muscle after PCI (adjusted odds ratio 1.09, 95% confidence interval 1.02 to 1.16, p = 0.012). In conclusion, the mechanical force of a contrast injection decreases thrombotic burden in patients with ST-segment elevation myocardial infarction pretreated with eptifibatide but not with placebo. Future trials of intracoronary pharmacotherapies should include a control arm in which saline is injected to account for the potential clot disaggregation that occurs as a result of iodinated contrast injections, particularly if the patient has been pretreated with aggressive pharmacotherapy.

Coronary angiographic findings do not predict clinical outcome in patients with unstable angina

Objectives. The presence of thrombus formation and type of coronary artery lesion were determined in patients with unstable angina and correlated with the angiographic findings and clinical outcome.Background. Some previous studies have suggested that thrombus formation and lesions are predictive of the angiographic and clinical findings. This was evaluated in a retrospective analysis of 159 patients participating in the placebo-controlled Unstable Angina Study Using Eminase (UNASEM) trial on the effect of thrombolysis in unstable angina.Methods. Patients without a previous myocardial infarction who presented with a typical history of unstable angina in the presence or abnormal findings on the electrocardiogram indicative of ischemia were included in the study. After baseline angiography, study medication (anistreplasc or placebo) was given to 126 of 159 patients. Thirty-three patients did not receive medication because of significant main stem disease or normal coronary arteries or for other reasons. Angiography was repeated after 12 to 28 h.Results. Quantitative angiography showed a significant decrease in diameter stenosis in the anistreplase-treated group compared with the placebo-treated group (decrease 11% vs. 3%, p = 0.008). No differences in clinical outcome were found when thrombolytic treatment was compared with placebo (p = 0.98). Neither the presence nor absence of thrombus formation (p = 0.98) nor the type of lesion (p = 0.96) was related to the changes in diameter stenosis or to clinical outcome (p = 0.90 and p = 0.77, respectively). The power of these analyses to detect a 20% difference varied between 56% and 74%.Conclusions. In this selected group of patterns with unstable angina, type of coronary artery lesion and the presence or absence of thrombus formation does not predict clinical outcome.

High frequency rotational ablation: an alternative in treating coronary artery stenoses and occlusions.

To prove the safety and effectiveness of high frequency rotational ablation of coronary artery stenoses and occlusion in humans. 106 patients with symptoms (91 men, 15 women) who had 67 significant stenoses, mainly types B and C, and 46-chronic occlusions. Mean change in diameter stenosis after rotational angioplasty alone and in combination with percutaneous transluminal coronary angioplasty immediately after treatment and 24 hours and six months later; restenosis rates at six months; complication of treatment. Rotational ablation could not be used in five stenoses and 16 chronic occlusions because of inability to reach or cross the lesion with the Rotablator guide wire. In four cases rotational ablation failed. Initial angiographic and clinical success by rotational ablation was achieved in 40 of the 67 stenoses (60%) and in 18 of the 46 chronic occlusions (39%). Additional balloon angioplasty was performed in 45 patients, increasing the success rates to 79% and 54%, respectively. In the 62 stenoses treated by rotational ablation the angiographic diameter stenoses were reduced from 76% (SD 14%) to 32% (14%) after Rotablator treatment alone and from 75% (11%) to 33% (17%) with additional balloon angioplasty. In the 30 chronic occlusions treated by rotational ablation the angiographic diameter stenoses were reduced to 38% (18%). At six months angiographic restenosis was evident in nine of the 25 (36%) stenoses treated with rotational ablation alone, in seven of the 22 (32%) stenoses treated with rotational and balloon angioplasty, and in 14 of the 24 (58%) chronic occlusions. There were no procedural deaths and two patients (2%) underwent emergency coronary artery bypass grafting. Although no transmural infarction occurred, there were five (6%) non-Q wave infarctions (two embolic side branch occlusions, two subacute occlusions, and one acute occlusion). Clinically insignificant slight increases in creatine kinase activity were seen in five patients (6%). Severe coronary artery spasm unresponsive to medical treatment was provoked in seven cases (8%). High frequency rotational ablation is a safe and effective method for treating type B and C coronary artery lesions with results comparable to percutaneous transluminal coronary balloon angioplasty. The combined use of rotational ablation and balloon angioplasty is feasible and is necessary in about half of all procedures, in most cases because the lumen created by the biggest burr is too small.