AXONIKI angiography
N. P. Bontozoglou, Director Department of CT - MRI Athens Medical
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The need to apply the results from the large number of catheter made annually, of which only a small percentage goes to health-care operations.
* It has great credibility to the exclusion of coronary artery disease.
* It has predictive value for both clinical cardiac events and for the survival of the patient.
* The accuracy of the results of the examination is greatly influenced by the experience and equipment of the laboratory.
* The principal indication for the method are weak small to moderate risk for coronary heart disease with atypical symptoms and equivocal laboratory testing to avoid unnecessary catheterization.
* The timing of the data and the resolution is more significant than the number of sections of the machine.
* It is often useful administration of beta-blockers before testing.
* Than classical angiography, which remains the gold standard to characterize the degree of stenosis, is bloodless, has a high negative predictive value and can be classified the quality of atherosclerotic plaques. Outweighs the magnetic angiography.
* The benefit of examining significantly exceed the theoretical effects of radiation, which anyway is the classic angiography and scintigraphy heart.
The Athens Medical is pioneering the field of CT angiography, which it began implementing in 2000, with the first hospitals worldwide.
In the continuous renewal of equipment recently installed a new multivolume Cardiology CT scanner SOMATOM SENSATION CARDIAC company SIEMENS, which has:
The fastest time of rotation of the tube to obtain the data in 0.24 seconds by providing pictures free mobile pests.
The smallest section thickness Today: 0.6 mm, allowing the creation of high definition images to enhance accurate, measurement and identification of bottlenecks.
Specific programs functional study of the left ventricle.
The latest programs by significantly reducing the radiation dose radiation.
On this occasion, here are some, hopefully useful, information about the axial angiography:
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Three factors influence the effectiveness of the review:
A. Experience: The performance review, the creation of images and particularly the assessment of coronary stenosis requiring considerable experience. In Athens Medical've reviewed to date over 3000 patients. We also announced in Greece and abroad and winning pioneering studies on the method.
B. Equipment: The method is only possible with newer type Polytomikous CT scanners, equipped with special heart programs, which allow high resolution and short time data collection so as to avoid motor interference.
C. Selection of patients: The method, at least at the present stage of development, is really useful in specific indications. In Athens Medical care order in consultation with a doctor to look is in the categories of patients may benefit from this method.
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What is today the indications of CT angiography:
O unknown coronary patient with:
- Atypical symptoms and fatigue test questionable or myocardial scintigraphy.
- Acute abdominal pain with normal ECG and normal blood tests.
H axial angiography reliably excludes significant stenoses of coronary arteries in a population of small to moderate risk of coronary heart disease. The method has a negative predictive value greater than 95%. As a result, if the test did not show significant pathological findings of the audit of coronary imaging can stop here and thereby avoid "unnecessary" catheterization. The information is believed to be enhanced by the development of the method.
What offers the axial angiography control after by-pass fitting stent;
The axial angiography study well the patency of grafts, the vein on his own, which have greater diameter. Difficulty highlight bottlenecks can occur if the anastomoses are many metal clips or native coronary vessels of these patients, which is often apotitanomena. This method can bring out the blockage or narrowing of the lumen of the stents. The literature indicates that the youngest CT scanners 64 intersections sensitivity to the discovery of significant bottlenecks than 90% for stents with a diameter greater than 3 mm.
You need to administration of beta-blockersprin the examination?
The many tight cause interference in kinetic examination of CT angiography. The administration of beta-blockers help the tight not exceed 65-75/to minutes so that your data in the phase of the heart telodiastoliki not "polluted" by the systolic phase. This parameter is not related to the number of sections of the machine. Some machines using dual CT scanners reduce the problem again but the tests seem to have fewer artifacts when the shake is relatively less. In addition, the administration of beta-blockers helps in keeping stable tight, the best application of modern methods to reduce radiation.
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How the axial angiography compared with other coronary angiography;
Conventional coronary angiography: examination of the election remains to measure the extent of bottlenecks and an important determinant of the treatment. The axial angiography has three important advantages over classical: The bloodless examination, the high negative predictive value and the immediate emergence and characterization of the quality of atherosclerotic plaques.
Magnetic angiography: The resolution is lower than axial. Also, the examination is more difficult to implement and mostly devoid of stability in the quality of outcome. At least in the near future there will be axial angiography in noninvasive coronary imaging.
Contraindications to perform CT angiography
Presence of multiple calcification. It is the most common factor in reducing efficiency of the method. Marked toichomatikes calcifications more difficult to study the lumen of the coronary arteries.
Renal failure. Allergy to contrast. The result of intravenous iodinated contrast. The amount used is usually 80-100 cc.
Arrhythmia, tachysfygmia. Cause interference motor, but using modern scanners are limited.
How much radiation is the axial angiography;
The published measurements of radiation dose for a CT angiography examination vary significantly from 8 to 20 mSvs. O new computed tomography scanner of Athens Medical implement specific programs and reduction of radiation dose is as high as in classical angiography or scintigraphy heart.
The general rule for tests containing radiation is used by a medical indication, and designed to be obtained all the necessary information at the lowest possible radiation. Thus the potential benefit to the patient substantially exceeds the theoretical effects of radiation.