![]() When the patient, operator, technique, and stent type are the same, vessel caliber and stent length both appear to influence the restenosis rate. Multivessel stenting including treatment of lesions in small-caliber vessels can be performed with a good clinical and angiographic outcome. The overall restenosis rate was 24% in the small vessel (9 mm length stent, 17% 16 mm length stent, 30%) and 15% in the large vessel (9 mm length stent, 3% 16 mm length stent, 22%), respectively. The result, if severe enough, is to reduce perfusion of brain parenchyma resulting in ischemic symptoms, infarction, and its sequelae. ![]() Six-month angiography was performed in 87 patients (92% of those eligible). Increasingly it is also becoming apparent that small caliber vessels which are in contact with blood in CSF are also narrowed - down to 15 micrometers - far too small to be visible on angiography, let alone CTA/MRA. The mean reference diameter for the small vessel was 2.35 mm and the large vessel 3.22 mm. One patient suffered a Q-wave myocardial infarction, one a non-Q-wave infarction, eight underwent percutaneous reintervention, two coronary artery bypass graft surgery operations, and five stenting of other nonstudy lesions. Six months postprocedure, there were no deaths or late stent occlusions. Additional lesions were treated in 23% of patients. Of 94 patients enrolled, 76% were male, mean age was 62 years (range, 40-85), 41% were hypertensive, 18% had diabetes, 15% were current smokers, and 64% had hypercholesterolemia. This multicenter prospective quantitative angiographic study evaluated patients with de novo coronary disease undergoing intervention who had at least two lesions or = 3.0 mm diameter (9 or 16 mm nine-cell NIR stent). We determined the effects of these factors in patients with lesions treated in both small- and large-diameter coronary arteries. Restudy of arteriograms suggests that branch-angle may be determined by branch vessel destination.Retrospective analyses of patient cohorts undergoing stent deployment have shown that small vessel diameter and long lesion length are two angiographic predictors of increased restenosis. The results of these postmortem measurements on human coronary arteriogram suggest that coronary artery caliber may adjust to minimize energy loss at the branch-point but that branch-angle is determined by other factors. The included angle between branches varied from 32 degrees to 124 degrees without respect to relative or absolute vessel calibers. No relationship could be found between branch-angle and vessel caliber. Fifty-seven branch-angles were determined by graphic analysis of postmortem biplane coronary arteriograms. Area ratio varies with changes in the relative calibers of branch vessels. Mean area ratio, the sum of the cross-sectional area of the branches divided by the area of parent vessel, decreased with greater arteriographic disease. The exponent, on the average, is less with increasing grades of vascular disease for left main coronary artery branch-points. ![]() ![]() Measured diameters (D) of parent and branch vessels corresponded well to the theoretical formula: (DParent)3 = (DBranch1)3 + (DBranch2)3.,in angiographically normal coronary arteries. Left main coronary artery branch-points were studied in 68 hearts with various degrees of angiographically defined coronary artery disease. Size relationships between parent vessel and its branches were determined for 42 left main and 53 other epicardial coronary artery branch-points in hearts with angiographically normal arteries. The formulas were based on the concept that blood vessel size and arrangement provided for blood flow with minimum energy loss. Measurements were made of parent and branch vessel diameters and of the included angles of branch-points from postmortem human coronary arteriograms to determine the usefulness of theoretical equations predicting the relationships between parent and branch vessel caliber and between arterial caliber and branch-angle. ![]()
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