36 research outputs found
Restenosis after percutaneous transluminal coronary angioplasty : a quantitative angiographic approach.
The first report of a nonsurgical technique of dilating areas of obstructive
atherosclerotic disease in the human arterial system was reported by Dotter and Judkins
in 1964 [1 ]. The technique described was for peripheral arteries, and involved the
passage of tapered dilating catheters of increasing diameter over a guidewire. This
technique had a limited following and was never widely accepted as an established mode
of treatment. 1n 1973 the use of a balloon dilatation catheter in humans was reported.
This consisted of the passage of a double lumen dilatation catheter with a non-elastic
balloon through an area of stenosis in the femora-popliteal and iliac arteries. This
balloon was then inflated to dilate the stenosis [2]. The late Andreas Griintzig adapted
this technique for use in human coronary arteries. 1n 1977 he first presented the
experimental results of dilating coronary artery stenosis [3]. The fir
Edge detection versus densitometry for assessing coronary stenting quantitatively
The optimal method used to analyze quantitatively the immediate angiographic results of coronary stenting in the coronary arteries has not been studied. Accordingly, minimal luminal cross-sectional area was determined by 2 methods, edge detection and densitometry, in 19 patients who underwent percutaneous transluminal coronary angioplasty (PTCA) and then coronary stent implantation for symptomatic coronary stenoses. The correlation coefficient, 0.73 before angioplasty, decreased to 0.59 after coronary angioplasty and then increased to 0.83 after stent implantation. The mean differences between edge detection and densitometric determinations of minimal luminal cross-sectional area were 0.31 +/- 0.51 mm2 before PTCA, -0.38 +/- 1.22 mm2 after angioplasty and 0.35 +/- 0.79 mm2 after coronary stenting. It is concluded that, although the correlation and variability in the measurement of minimal luminal cross-sectional area between edge detection and densitometry deteriorate after PTCA, they are improved after stenting, probably because of smoothing of the vessel contours by the stent and remodeling of the stented segment into a more circular configuration. Therefore, in the stented coronary artery, edge detection and densitometry are equally acceptable methods of analysis
Postangioplasty restenosis rate between segments of the major coronary arteries
__Abstract__
Conflicting data have been published regarding the rate of postangioplasty restenosis observed in diverse segments of the coronary tree. However, these studies may be criticized for their biased selection of patients, methods of analysis, and definitions of restenosis. In the present study, 1,353 patients underwent a successful coronary dilatation of ≥1 site. In all, 1,234 patients (91%) had a f
Coronary Artery Fly-Through Using Electron Beam Computed Tomography
BACKGROUND: Virtual reality techniques have recently been introduced into
clinical medicine. This study examines the possibility of coronary artery
fly-through using a dataset obtained by noninvasive coronary angiography
with contrast-enhanced electron-beam computed tomography. METHODS AND
RESULT
Left Main Coronary Angioplasty: Assessment of a “Risk Score” to Predict Acute and Long‐Term Outcome
Due to the recent emergence of adjunctive techniques such as cardiopulmonary bypass support, left main angioplasty may become more routinely applied in the near future. In order to choose the best possible therapy, a precise risk assessment will be desirable. Twenty‐two left main angioplasties were thus re
Comparative angiographic quantitative analysis of the immediate efficacy of coronary atherectomy with balloon angioplasty, stenting, and rotational ablation
Interventional cardiology has branched in two directions: devices that primarily dilate coronary stenoses and those that debulk coronary tissue. Presently the optimum coronary intervention has not been found. While patients are awaiting randomized trials, a comparison based on matched quantitative coronary analysis may be useful to evaluate results of new interventional techniques. Therefore we compared 51 patients undergoing atherectomy with individually matched patients who were undergoing balloon angioplasty and stenting. The lesions were matched according to location of stenosis and reference diameter. Atherectomy and stenting resulted in larger gains in minimal luminal diameter compared with conventional balloon angioplasty. The minimal luminal diameter was increased from 1.2 +/- 0.4 mm to 2.6 +/- 0.4 mm in the atherectomy group and from 1.2 +/- 0.3 mm to 1.9 +/- 0.4 mm in the angioplasty group (p less than 0.00001). Atherectomy and stenting resulted in similar gains in minimum luminal diameter (1.4 mm vs 1.3 mm, p = NS). In addition, atherectomy and stenting appear to be more effective in resisting elastic recoil because of tissue removal and an intrinsic dilating effect, respectively. In matched populations directional atherectomy and stenting appear to be more effective intracoronary interventional devices than balloon angioplasty based on the immediate results. However, atherectomy is limited in smaller coronary vessels because of its larger size
Intravenous coronary angiography by electron beam computed tomography: a clinical evaluation
BACKGROUND:-Noninvasive detection of coronary stenoses with electron beam
CT (EBCT) after intravenous injection of contrast medium has recently
emerged. We sought to determine the diagnostic accuracy of EBCT
angiography in the clinical setting using conventional coronary
angiography as the "gold standard." METHODS AND RESULTS: Thirty-seven
patients (30 men) were investigated. After intravenous injection of 150 mL
of contrast medium, 40 to 60 consecutive transaxial tomograms, covering
the proximal and middle parts of the coronary arteries, were obtained with
ECG triggering at end diastole during breath-holding. Three-dimensional
reconstructions of the proximal and middle parts of the arteries were
compared with the conventional angiograms. Of the 259 proximal and middle
coronary segments, 211 (81%) were analyzable by EBCT. Of the left anterior
descending coronary artery (LAD) segments, 95% were assessable. Right
coronary artery (RCA) and left circumflex artery (LCx) segments were
assessable in 66% and 76%, respectively. Overall sensitivity and
specificity to detect a >50% diameter stenosis were 77% and 94%,
respectively. This was 82% and 92% for the LAD, 60% and 97% for the RCA,
and 83% and 89% for the LCx (all figures based on assessable lesions).
CONCLUSIONS: Intravenous EBCT coronary angiography is a promising coronary
imaging technique. The technique is not yet robust enough to be an
alternative to conventional coronary angiography. It can detect and rule
out significant coronary artery disease of the left main proximal and mid
portions of the LAD with good accuracy
In vivo assessment of three dimensional coronary anatomy using electron beam computed tomography after intravenous contrast administration
Intravenous coronary angiography with electron beam computed tomography
(EBCT) allows for the non-invasive visualisation of coronary arteries.
With dedicated computer hardware and software, three dimensional
renderings of the coronary arteries can be constructed, starting from the
individual transaxial tomograms. This article describes image acquisition,
postprocessing techniques, and the results of clinical studies. EBCT
coronary angiography is a promising coronary artery imaging technique.
Currently it is a reasonably robust technique for the visualisation and
assessment of the left main and left anterior descending coronary artery.
The right and circumflex coronary arteries can be visualised less
consistently. Improvements in image acquisition and postprocessing
techniques are expected to improve visualisation and diagnostic accuracy
of the technique